Median Tumor-infiltrating Lymphocytes Research Articles

Abstract PO3-14-06: Immunologic features and association with prognosis in hormone receptor-positive/HER2-negative (HR+/HER2-) metastatic breast cancer (MBC) treated with chemotherapy (CT) or CDK4/6-inhibitors (CDK4/6i) + endocrine therapy (ET)

Abstract Purpose: Little is known regarding the prognostic and predictive role of tumor immunological features in HR+/HER2- MBC treated with CT or CDK4/6i+ET. Methods: The Italian KENDO phase 2 trial randomized CT-naïve patients with HR+/HER2-neg. MBC with aggressive characteristics to receive CDK4/6i+ET (arm A) or CT+/-ET (arm B). Primary endpoint was progression-free survival (PFS). A tumor sample from the primary or metastatic tumor (archived or newly-obtained) was mandatory for inclusion. In this correlative biomarker analysis, tumor-infiltrating lymphocytes (TILs) and tertiary lymphoid structures (TLS) were detected on baseline tumor samples by hematoxylin&eosin staining, while immune genomic signatures were assessed with the nCounter BC360 panel. Immune pattern at immunohistochemistry was defined as inflamed (IF), excluded (IE) or desert (ID). TILs and signatures were dichotomized (high vs. low) with the maximally-selected rank statistics (MSRS) method. Survival analyses were conducted with the Kaplan-Meier (KM) method and differences were tested with log-rank test. Hazard ratios (HR) with 95% confidence intervals (CI) were estimated with Cox regression. Significance was set at p≤0.05. Since the trial was stopped earlier due to slow accrual all analyses were exploratory. Results: Forty-nine patients were randomized, 17 (34.7%) in arm A and 32 (65.3%) in arm B. No significant clinicopathological differences were observed at baseline between the two arms, except for tumors in arm B showing more TLS (50.0% vs. 12.5%, p=0.013). Median PFS (mPFS) with CT+/-ET was numerically shorter than mPFS with CDK4/6i+ET (11.2 vs. 19.9 months, HR: 1.41, 95%CI: 0.75-2.64, p=0.289). The median OS (mOS) for arm A was not estimable (NE) vs. 30.6 months in arm B (p=0.283). In arm A, median TILs levels were 3% (interquartile range [IQR]: 1-5%) and TLS, with/without germinal centers, were present in 2 cases (12.5%). These were also the only IF tumors in the arm, whereas the rest (87.5%) were ID. In arm B, 7 (25.0%) tumors were IF, 19 (87.5%) ID and 2 (7.1%) IE. Median TILs were 4.5% (IQR: 2-12.8%) and TLS were present in 50% cases. In arm A, ID tumors showed lower mPFS than IF (15.8 vs. 27.5 months), with concordant trend at the OS KM curve. In arm B there was no clear difference in PFS, but IF tumors did not reach mOS, differently from ID (28.7 months) and IE (28.1 months). High vs. low TILs levels were significantly associated with better PFS (p=0.003) and OS (p=0.005) in arm A. High levels of a TGFβ gene expression signature were significantly associated with better PFS (p=0.020) and OS (p=0.005) in arm A and PFS (p=0.03) in arm B; higher levels of a cytokine/chemokine signature were associatedwith better PFS (p=0.02) in arm A, and higher levels of a mastcells signature was associated with worse OS in both arms (p=0.02 and p=0.03). In arm B, higher levels of a macrophage (p < 0.001) and antigen presentation signatures (p=0.04) were associated with worse and better OS, respectively, whereas higher levels of an immune infiltration and a cytotoxic cells signature were associated with better PFS (p=0.03 both). TLS presence was numerically associated to longer mPFS (23.5 vs. 15.8 months) in arm A, with consistent OS KM curve’s trend, and longer mOS (44.5 vs. 28.1 months) in arm B. Conclusions: The KENDO trial further supports CDK4/6i+ET use in aggressive CT-naïve HR+/HER2- MBC. Biomarkers of immune activation such as IF tumors, higher TILs and presence of TLS pointed towards better survival outcomes. Genomic immunological features also showed prognostic effect, with differences according to treatment arm and/or the immune process or cell line tracked. Further research on larger cohorts is needed to confirm these preliminary findings. Citation Format: Francesco Schettini, Michela Palleschi, Francesca Mannozzi, Fara Brasó-Maristany, Lorenzo Cecconetto, Patricia Galván, Marita Mariotti, Alessia Ferrari, Emanuela Scarpi, Anna Miserocchi, Oriana Nanni, Esther Sanfeliu, Aleix Prat, Andrea Rocca, Ugo De Giorgi. Immunologic features and association with prognosis in hormone receptor-positive/HER2-negative (HR+/HER2-) metastatic breast cancer (MBC) treated with chemotherapy (CT) or CDK4/6-inhibitors (CDK4/6i) + endocrine therapy (ET) [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-14-06.

Abstract PO1-03-09: Transcriptomic profiling of ER-negative and ER-low, HER2-negative breast cancer and its implications on immune regulation

Abstract Background: The recommended cut-off of < 1% positive cells to define estrogen receptor (ER) negative status in breast cancer (BC) is highly debated. Few data exist on transcriptomic features of ER-low BC, suggesting no major differences vs ER-neg. Among HER2-negative BCs, we compared gene-expression profiling (including PAM50 intrinsic subtyping) according to ER status (ER-neg: 0% vs. ER-low: 1-9%) and assessed its impact on Tumor-infiltrating lymphocytes (TILs) levels. Methods: Across two cancer centers, stage I-III HER2-negative BCs FFPE samples were reviewed for ER status. All ER-low (ER 1-9%) samples were identified and a cohort of ER-neg BC samples, matched for age and stage, was also retrieved. A small cohort of pts with intermediate ER expression (ER-int: 10-50%) was included as a control cohort. Expression of 776 BC–related genes was evaluated by nCounter® (Breast Cancer 360TM Panel) and intrinsic molecular subtyping was determined using the PAM50 subtype predictor. A False Discovery Rate (FDR) corrected unpaired two-class SAM was used to identify genes differentially expressed in different subgroups. TILs were evaluated on archival H&E slides following guidelines. Results: Of 116 stage I-III HER2-neg BC pts included, 39 had ER-neg BC, 65 had ER-low BC, and 12 had ER-int disease. PAM50 intrinsic subtype distribution was similar in ER-neg and ER-low BCs, (with an enrichment in basal-like tumors), while both subgroups differed significantly from ER-int samples (Table). As compared to ER-neg tumors, ER-low BCs showed significantly higher expression of GATA3 gene and lower expression of EDN1 and PROM1 genes by SAM analysis (FDR< 5%); however, when the analysis was limited to PAM50 basal-like tumors (N=77) we only identified two genes that were downregulated in ER-low BCs (EDN1, PROM1) as compared to ER-neg BCs. On the contrary, significant differences in transcriptomic regulation were observed between ER-low and ER-int BCs, with ER-low BCs showing significantly higher expression of 53 genes and lower expression of 398 genes, as compared to ER-int (SAM analysis FDR< 5%). We previously reported similar TIL levels in ER-low and ER-neg tumors. In both ER-low and ER-int BCs, PAM50 basal-like subtype was associated with significantly higher TILs: median TIL levels 20 (range 0-80) and 6 (range 1-40) for PAM50 Basal-like BCs versus other PAM50 subtypes respectively in ER-low samples (p< 0.001); median TIL levels 53 (range 25-80) and 5 (range 0-10) for PAM50 Basal-like BCs versus other PAM50 subtypes respectively in ER-int samples (p=0.036). No significant difference in TIL levels according to PAM50 subtyping were observed in ER-neg tumors. No significant difference in mRNA levels for PD-1 (PDCD1) and PD-L1 (CD274) genes was observed between ER-low and ER-neg tumors. Conclusions: Among patients with HER2-neg BC, gene-expression profiling is similar in ER-neg (i.e., < 1%) vs. ER-low tumors with a high prevalence of PAM50 Basal-like tumors and few differentially expressed genes. In both ER-low and ER-int HER2-neg BCs, PAM50 Basal-like subtype is also associated with higher TIL levels. Our results strongly indicate that HER2-neg/ER-low BCs and HER2-neg/ER-neg BCs are similar biological entities, thus further supporting the use of similar treatments in patients with early-stage ER-low and triple-negative BC, including immune checkpoint inhibitors. PAM50 intrinsic subtype distribution according to ER levels Citation Format: Gaia Griguolo, Claudio Vernieri, Davide Massa, Lorenzo Nicolè, Claudia Pinato, Federica Miglietta, Andrea Vingiani, Silvia Brich, Riccardo Lobefaro, Francesca Schiavi, Matteo Fassan, Giancarlo Pruneri, Valentina Guarneri, Maria Vittoria Dieci. Transcriptomic profiling of ER-negative and ER-low, HER2-negative breast cancer and its implications on immune regulation [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-03-09.

The impact of exercise training on the pathologic response and tumor immune microenvironment in breast cancer after neoadjuvant chemotherapy: An exploratory study.

e12596 Background: In early breast cancer (BC), pathological complete response (pCR) is an efficacy endpoint of neoadjuvant chemotherapy (ChT) and percentage of tumor-infiltrating lymphocytes (TILs) is a prognostic biomarker. Although exercise training is an evidence-based supportive care across the BC journey, one open question is its impact on the antitumor effect of neoadjuvant ChT. The authors aim to investigate the effects of a supervised exercise training program (STEP) in pCR and TILs in BC women undergoing neoadjuvant ChT. Methods: MAMA_MOVE_Gaia on Treatment (ISRCTN, ISRCTN32617901) is randomized controlled trial in which women with early BC undergoing anthracycline containing ChT were randomized in a 1:1 ratio to a SETP or to usual care, close to recruitment in January 2022. For this exploratory analysis, we retrospectively identified patients who underwent neoadjuvant ChT, and compare pCR and TILs between the two arms. Results: Sixty-four participants were included, aged from 26 to 72 years old (mean = 50.3, SD = 10.1) majority with stage II and III (n = 58, 90,6%) and HER2+ (n = 23, 35.9%) or triple negative (n = 19, 29.7%) disease. The pCR in STEP arm had a prevalence of 56.7% and in the usual care arm of 55.9%(p = 0.950). In the STEP arm median TILs were, for the biopsy and tumor site, of 5.0 (range 0.0-80.0) and 5.0 (range 5.0-30.0). In the usual care arm, median TILs were, for the biopsy and tumor site, of 5.0 (range 0.0-90.0) and 0.0 (range 0.0-30.0). There was no difference between groups for TILs of the biopsy (p = 0.907). Higher TILs of the tumor site was marginally associated with the STEP arm (p = 0.082). Conclusions: Despite the results obtained, it is believed that a larger sample may lead to different results. However, these data could also support future research in this field, bringing new insights for cancer survivors continuum of care.

Abstract P1-14-05: Pembrolizumab and Oral Metronomic Cyclophosphamide in Patients with Chest Wall Breast Cancer (PERICLES): an immune-biomarker analysis of tumor infiltrating lymphocytes (TILs) and programmed cell death ligand protein 1 (PD-L1)

Abstract Background: Breast cancer (BC) with lymphangitic spread to the chest wall is a rare clinical entity affecting about 2% of pts, with poorer survival outcomes. A brisk immune infiltrate is typically reported, with up-regulation of inflammation and immune-tolerogenic genes. PERICLES clinical trial is testing the administration of pembrolizumab 200 mg Q3w plus cyclophosphamide 50 mg daily for BC with chest wall disease. In this exploratory biomarker analysis, we assessed the prevalence of the TILs score and the PD-L1 combined positive score (CPS) obtained from skin biopsies performed at screening. Methods: PERICLES (NCT03971045) is a single-center, single-arm, interventional phase 2 trial. Main inclusion criteria: histologically confirmed, inoperable, locally recurrent and/or metastatic BC with lymphangitic spread to the chest wall (including and not limited to inflammatory BC); PD-L1 positive (CPS≥1; 22C3 pharmDx®) and/or TILs positive (≥1% of CD3 or CD20-positive cells) disease on skin biopsy obtained at screening; progression to at least one prior cytotoxic treatment; no prior immune checkpoint inhibitors. The primary endpoint is objective response rate as per immune-related RECIST criteria. 46 pts will be required for the study to power for the primary hypothesis. In this analysis, we describe the baseline immune-biomarker status, in the overall population enrolled based on hormone receptor status and HER2. Correlative analyses were provided (significance at p-value< 0.05). Results: 37 pts were screened with skin biopsy of the chest wall disease (June 2020-June 2022). Biopsy and biomarker analysis were successful in 35 pts. Median age was 58 years (range: 35-79). Among the 35 pts included in the biomarker analysis, 25 (71%) pts had visceral disease and 20 (57%) had skin metastases at the diagnosis of metastatic disease; median number of previous lines of therapies was 4 (range: 1-12) and of chemotherapies was 4 (range: 1-10). 2 (6%) pts had HER2-positive disease, 13 (37%) HR-positive/HER2-negative disease, and 20 (20%) had triple-negative breast cancer (TNBC). TILs and PD-L1 CPS were < 1 in 15 (43%) pts; 20 pts (57%) were eligible for CPS and/or TILs criteria: 16 (43%) were both PD-L1 positive and TILs positive, 4 only PD-L1 positive. Median PD-L1 CPS score was 5 (range: 0-80%) in the overall population and 17 (range: 2-80%) in eligible patients; 16/35 pts (43%) had CPS≥10. Median TILs score was 0% (range: 0-55%) in the overall population, 0% (range: 0-40%) in the HER2-negative (n=16), 0% (range 0-20%) in the HER2-low (n=18), and 37.5% (range 20-55%) in the HER2-positive (n=2). No significant differences in baseline characteristics were found between positive and negative biopsies (Table). Considering only the TILs, a statistically significant correlation between HER2-positive status and TILs score was demonstrated (p< 0.001); no other correlations between receptor status (estrogen receptor, progesterone receptor, HER2) and PD-L1 CPS or TILs emerged. Conclusions: 57% of patients with chest wall BC have skin metastases positive for PD-L1 CPS and/or TILs score ≥1%. To our knowledge, these are the first prospective data on the prevalence of PD-L1 and TILs in metastatic BC with lymphangitic spread to the chest wall, highlighting potential actionability through therapeutic strategies with new immune-oncology agents in this setting. Table: Characteristics of patients included in the biomarker analysis (n=35) *Calculated with T test or Fisher’s exact test, as appropriate. Keys: BC, breast cancer; CPS, combined positive score; CT, chemotherapy; HR; hormone receptor; n, number; NA; not available; PD-L1, Programmed cell death ligand protein 1; TILs, tumor infiltrating lymphocytes; TNBC, triple negative breast cancer. Citation Format: Carmine Valenza, Pier Paolo Maria Berton Giachetti, Paola Zagami, Eleonora Nicolò, Dario Trapani, Laura Boldrini, Beatrice Taurelli Salimbeni, Liliana Ascione, Gabriele Antonarelli, Chiara Corti, Angela Esposito, Carmen Criscitiello, Nicola Fusco, Giuseppe Curigliano. Pembrolizumab and Oral Metronomic Cyclophosphamide in Patients with Chest Wall Breast Cancer (PERICLES): an immune-biomarker analysis of tumor infiltrating lymphocytes (TILs) and programmed cell death ligand protein 1 (PD-L1) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-14-05.

Prognostic significance of tumor-infiltrating lymphocytes in predicting outcome of distal cholangiocarcinoma in Thailand.

Patients with distal cholangiocarcinoma (dCCA) generally have poor outcomes because of late presentation and diagnosis. Therefore, prognostic factors for predicting outcomes are essential to improve therapeutic strategies and quality of life. Tumor-infiltrating lymphocytes (TILs) have been reported as a prognostic predictor in several cancers. However, their role in dCCA is still unclear. This study aimed to evaluate the association of TILs with outcome in patients with dCCA. Fifty-two patients were evaluated for the percentage rate of TILs in their cancers, and a median TIL level was used to divide the patients into two groups. Survival, multivariate, and correlation analyses were performed to determine the prognostic factors. Results showed that a low TIL level was associated with poor survival. Multivariate analysis revealed TILs as an independent factor for poor outcome. Moreover, TILs were markedly correlated with growth patterns, and both were applied to classify patients with dCCA. Subgroups of TILs with growth pattern incorporation improved stratification performance in separating good from poor patient outcomes. This study suggested that TILs could be a prognostic factor for predicting survival and for clustering patients with dCCA to improve prognostication capability. This finding may be incorporated into a new staging system for stratifying dCCA in Thailand.

Digital quantification of lymphocytic infiltration on routine H&E images and immunotherapy response in non–small cell lung cancer.

9066 Background: Current biomarker(s) for immuno-oncology (IO) therapy response prediction in lung cancer are limited. Additional predictive biomarkers are useful to help refine patient selection and guide precision therapy. Methods: Biopsy and surgical specimens stained with hematoxylin-eosin (H&E) were subjected to whole-slide scanning for 446 advanced stage non-small cell lung cancer (NSCLC) treated with single agent immune check point inhibitors (ICI). A machine learning model was trained on H&E images for classification of tumor infiltrating lymphocytes (TILs), tumor cells, and stromal cells in specific tissue types. Results: TIL levels were found to be highly variable, with a range of 12 to 4270 cells/mm2, and median of 319 (Q1 = 159, Q3 = 681). TIL levels were assessed on tissue samples from multiple organs which had shown primary or metastatic NSCLC, and were similar across all specimen sites except the liver, for which median TIL levels were significantly lower, at 90 cells/mm2. There was no correlation between tumor mutational burden (TMB) and TIL levels, while high TIL levels were correlated with high PD-L1 (≥ 50%) expression. Patients who experienced a partial/complete response to ICI therapy had a trend to higher median TILs compared to those who had progressive/stable disease (350 versus 310 cells/mm2, P = 0.09). In a multivariable analysis after controlling for covariates (incl. sex, age, cigarette smoking, ECOG, PD-L1, TMB & treatment line), a higher TIL level (≥ 250 cells/mm2) was an independent predictor of IO response for both progression-free survival (PFS; HRadj 0.70; 95% CI, 0.55 - 0.89; P = 0.003) and overall survival (HRadj 0.73; 95% CI, 0.56 - 0.95; P = 0.02). In a ROC analysis considering single biomarkers, PD-L1 had the highest AUC (0.68, P < 0.001), while TIL (AUC = 0.53, P = 0.08) and TMB (AUC = 0.55, P = 0.05) had similar AUC values for classifying responders from non-responders based on objective response rate. Using weighted linear regression approach to combine the biomarkers, paired PD-L1/TMB had the greatest AUC (0.70, P < 0.001) compared to PD-L1 single assay. In the PD-L1 negative (< 1%, N = 50) subgroup, TIL levels had superior predictive performance for classification of IO responders (AUC = 0.77, P = 0.02) compared to TMB (AUC = 0.57, P = 0.3), such that patients with a high TIL level (≥ 250 cells/mm2) had an improved PFS (median PFS: 2.7 vs 2.2 months; HR = 0.48; 95% CI, 0.26 - 0.87; P = 0.02). Conclusions: Digital TIL quantification with use of machine learning is feasible. TIL levels appear to be a robust and independent biomarker of likelihood of response to IO treatment in NSCLC, especially in the PD-L1 negative subgroup. The findings of this study are under validation in additional lung cancer cohorts.

Relationship between tumor infiltrating lymphocytes and clinicopathological features in Peruvian gastric cancer.

e16080 Background: Role of tumor-infiltrating lymphocytes (TIL) over clinicopathological features including Mismatch Repair (MMR), HER2 status, Epstein Barr Virus (EBV) and Helicobacter pylori (HP) infection is not well understood in gastric cancer (GC). Methods: TIL level and HP infection was also evaluated in H&E from 503 Peruvian GC patients who underwent surgery. Density of CD3+ T cells, CD8+ cytotoxic T cells, CD163 M2 macrophages, as well as MMR and HER2 status were determined by immunohistochemistry. HP and EBV infection was also detected by qPCR in a 234 cases subset. Results: Median age was 62 years and 50.1% were female, most tumors were grade 3 (59.1%), intestinal subtype (44.8%) and stage III (59.8%). MMR loss was found in 29.4% and HER2+ in 4.7%. HP+ was detected by H&E in 55.7% and by qPCR in 63.7%. EBV+ by qPCR was found in 20.5% and co-infection along with HP in 9.4% (22/234). Stage (p < 0.001), intestinal histology (IH) (p = 0.019), grade (p = 0.006) and lymphovascular invasion (p < 0.001) were associated with longer survival. Median TIL was higher in invasive border (IB) and stromal (ST) than intratumoral (IT) compartment but there were significantly correlated (p < 0.001). High IT TIL was associated with absence of HP H&E (p = 0.009). High ST TIL was associated with older age (p < 0.001), IH (p < 0.001), grade 1 (p = 0.009), lower stage (p = 002), MMR loss (p = 0.019) and EBV+ (p = 0.001). Density of CD3 and CD8 were significantly correlated in IT and ST compartments (p < 0.001). High CD3 density in IT compartment was associated with grade 3 (p = 0.001) and HP- (p = 0.02), and in ST was associated with IH (p = 0.005), grade 1- 2 (p = 0.002) and MMR loss (p = 0.04). High IT CD8 was associated with HER2- (p = 0.016), HP- (p = 0.014) and EBV+ (p = 0.012). High ST CD8/CD3 ratio was associated with diffuse histology (p = 0.034), grade 3 (p = 0.013), more advanced stage (p = 0.022) and recurrence (p = 0.014). High ratio of IT CD8/CD3 was associated with MMR loss (p = 0.007). High ST TIL was associated with longer DFS (p = 0.007). Lower ratio of CD8/CD3 was associated with longer OS (p = 0.024) and DFS (p = 0.02). Conclusions: TIL levels and infiltrating immune subpopulations differs by clinicopathological features in GC including MMR loss, HER2 expression EBV and HP infection. ST CD8/CD3 was associated with recurrence and shorter DFS.

Human Papillomavirus, Cytomegalovirus Infection and P16 Staining in Breast Tumors from Peruvian Women.

Objective:To evaluate the frequency distribution of viral infections in Peruvian Breast Cancer (BC) lesions and its association with clinicopathological features. Additionally, a prospective evaluation of p16 and Tumor-infiltrating lymphocytes (TIL) levels were performed for developing a comprehensive analysis.Methods:Detection of high risk- human papillomavirus (HR- HPV) through qPCR was performed in 447 BC and 79 non-cancer frozen samples. Paired paraffin samples from 238 BC were stained with Human cytomegalovirus (HCMV) and p16 immunohistochemistry. TIL was calculated in 397 BC cases. Results:HCMV was positive in 72.5%. HR- HPV was detected in 2.9% of BC and 1.3% of non-malignant samples. P16+ was found in 28.15% and median TIL percentage was 30. HR- HPV infection was associated with non-ductal histology (p=0.003) and p16+ (p=0.017). Positive P16+ was associated with higher T stage (p=0.022), grade (p=0.009), TIL level (p=0.002), and triple-negative phenotype (p=0.021). Conclusion:HCMV is frequent, but HR- HPV infection is unusual in Peruvian BC. P16+ is associated with HR- PVH infection, high TIL and aggressive features.

Abstract P1-02-03: Tumor-infiltrating lymphocytes but not HER2 copy number or ratio show prognostic value in trastuzumab-treated HER2-positive breast cancer

Abstract Background: Around 15% of all breast cancers are HER2+, a subtype that prior to HER2-targeted therapy was associated with a poor prognosis. With advances in treatment the survival has dramatically improved, and previous studies suggest that the level of HER2 copies are predictive of the effect of anti-HER2 therapies. However, some patients progress despite HER2-targeted therapy and routine HER2 testing is hampered by inaccuracy to discriminate patients with therapy-resistant disease. Furthermore, tumor-infiltrating lymphocytes (TILs) in the tumor stroma shows prognostic value not only in triple negative but also in HER2+ breast cancer. However, the clinical utility in the adjuvant setting for HER2+ disease needs further validation. The aim of this study was to investigate the prognostic significance of HER2/CEP17 ratio, HER2 copy numbers and TILs among early breast cancer patients treated with HER2-targeted therapy. Materials and methods: A retrospective study cohort comprising a total of 584 patients with HER2+ early breast cancer, all treated with the monoclonal antibody trastuzumab targeting HER2 during 2006-2014 in the Stockholm Region, Sweden, was identified and HER2 re-testing (silver in situ hybridization and immunohistochemistry (IHC)) was performed on 474 whole tissue sections prior to neoadjuvant (18.1%) or adjuvant therapy. Stromal TILs were manually assessed on all hematoxylin-eosin stained slides. Registry-based information on patient- and tumor characteristics including treatment were completed from medical records with a median follow-up of 8.0 years. Results: Among the 474 analyzed tumors, 11.4% were HER2 IHC score 2+ and 86.7% were 3+. In addition, 61.6% were ER+ and the median TIL score was 15%. The median HER2 copy number was 9.8 signals/cell and only 12.9% had <6.0 average HER2 signals/cell and 2.5% had a HER2/CEP17 ratio <2.0. Survival analysis showed no significant association between HER2 IHC score (recurrence: p=0.58; breast cancer specific death: p=0.69), HER2 signals (p=0.77; p=0.73), HER2/CEP17 ratio (p=0.73; p=0.85), ER status (p=0.55; p=0.11), PR status (p=0.97; p=0.46), Ki67 (p=0.14; p=0.77) or tumor grade (p=0.71; p=0.16) with risk of recurrence or breast cancer specific death. The hazard ratio (HR) for recurrence did not significantly differ by HER2 signals/cell (HR 1.12, CI 0.53-2.37, p=0.77) or ER status (HR 1.18, CI 0.68-2.05, p=0.55). Tumors with low TILs were independently associated with recurrence (cutoff <40%: HR 4.5, CI 1.4-14.9, p=0.012) and breast cancer specific survival (cutoff <30%: HR 3.5, CI 1.2-10.1, p=0.02). Among the 56 recurrences (11.8%), 37.5% had ER- primary tumors and 82.4% of the 34 HER2-analyzed recurrent tumors remained HER2+. Conclusions: This study demonstrates that routine clinicopathological data, including HER2 status, is insufficient to predict breast cancer recurrence among patients treated with HER2-targeted therapy. Neither HER2 levels, HER2/CEP17 ratio or ER status correlated to risk of recurrence. Importantly, TILs showed robust prognostic potential in trastuzumab-treated patients. Our results emphasize the need for detailed molecular analyses to understand the biology behind resistance to HER2-targeted therapy and to further tailor therapy for HER2+ breast cancer patients. Citation Format: Stephanie Robertson, Caroline Rönnlund, Irma Fredriksson, Theodoros Foukakis, Johan Hartman. Tumor-infiltrating lymphocytes but not HER2 copy number or ratio show prognostic value in trastuzumab-treated HER2-positive breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-02-03.

Tumor-Infiltrating Lymphocytes in Patients With Advanced Laryngeal Cancer Undergoing Bioselection.

Bioselection to assess tumor response after induction chemotherapy has been introduced as an alternative treatment strategy to total laryngectomy for patients with advanced larynx squamous cell carcinoma (LSCC). Tumor-infiltrating lymphocytes (TILs) have proven to serve as prognostic biomarkers in head and neck cancer but have not been evaluated as a way to select patients for treatment paradigms. The aim of this study is to evaluate the role of pretreatment TILs in patients with advanced LSCC undergoing the bioselection paradigm. Retrospective study. Tertiary care hospital. Patients with advanced LSCC treated with bioselection and available tissue were included (N = 76). Patients were stratified into CD8-low and CD8-high cohorts by using the median TIL count. Kaplan-Meier survival analysis and multivariate cox regression were performed with SPSS version 26 (IBM). After controlling for tobacco use, tumor site, and stage, a high CD8 TIL count was an independent predictor of improved 5-year disease-specific survival (hazard ratio, 0.17 [95% CI, 0.03-0.84]; P = .03). CD8 TIL counts did not predict response to induction chemotherapy; however, subgroup analysis of patients treated with chemoradiation therapy revealed that CD8 TIL count was significantly associated with degree of response (P = .012). These findings support prior data published by our group showing that TILs are predictive of disease-specific survival in patients with head and neck cancer. CD8 TIL counts were significantly associated with degree of clinical response after induction chemotherapy. These results suggest that pretreatment assessment of tumor-infiltrating CD8 cells could be useful in selecting patients.

Tumor-infiltrating lymphocytes (TILs) in ER+/HER2- breast cancer.

The prognostic role of tumor-infiltrating lymphocytes (TILs) in ER+/HER2- breast cancer (BC) is debated. We evaluated the association of TILs and clinico-pathological features with distant disease-free survival (DDFS) in patients with ER+/HER2- BC treated at a single institution. A mono-institutional case-cohort series of 987 patients with early ER+/HER2- BC was retrospectively analyzed. TILs were considered both as continuous variable, and dichotomized in low (< 5%) vs high (≥ 5%). The main outcome was DDFS. Median follow-up was 7.5years (0.1-10). Univariate and multivariable Cox proportional hazards regression with inverse sub-cohort sampling probability weighting were used to evaluate the risk across groups. Median TIL count was 2% (Q1-Q3 1-4%). Higher TILs were positively associated with number of lymph nodes involved (p = 0.003), tumor grade (p < 0.0001), peritumoral vascular invasion (p = 0.003), higher Ki-67 (p = 0.0001), luminal B subtype (p < 0.0001), and chemotherapy use (p < 0.00019). In multivariable regression analysis, only higher Ki-67 expression retained significant association with TILs. At univariate Cox regression analysis, TIL expression (≥ 5% vs. < 5%) was not associated with DDFS (HR 1.08, 95% CI 0.80-1.46, p = 0.62). In patients treated with adjuvant chemotherapy, high TILs were associated with better DDFS (HR 0.52, 95%CI 0.33-0.83, p = 0.006), particularly in the group with Ki-67 ≥ 20% (HR 0.50, 95%CI 0.29-0.86, p = 0.01). High TILs in ER+/HER2- BC are significantly associated with clinico-pathological features of dismal outcome. TIL prognostic value seems different in patients treated with or without chemotherapy. Our findings suggest that the high-risk subgroup might be more immunogenic, thus deserving the exploration of immunotherapy approaches.

Prognostic value of tumor: Infiltrating lymphocytes and androgen receptors correlation in triple negative breast cancer.

e12571 Background: Little is known about correlation of tumor infiltrating lymphocytes (TIL) and androgen receptors (AR) and their joint effect on early triple-negative breast cancer (TNBC) prognosis. Analyzes to date evaluated mostly stromal TIL (sTIL) and intratumoral (iTIL), but not separately in central tumor (CT) and invasive margin (IM). Methods: We retrospectively analyzed consecutive sample of 152 early TNBC patients treated at our institution 2009-2012. TIL and AR were assessed using standard FFPE samples, TIL according to International Working Group for Evaluation of TIL recommendation, sTIL and iTIL in CT and IM, and AR by immunohistochemistry. Results: Median age was 58, 84% NOS, median T 2.2cm, 41% N+, 22%, 59% and 19% in stage I, II and III, respectively. Radical mastectomy was performed in 39%, adjuvant chemotherapy in 88% and radiotherapy in 74% of patients. Positive AR defined as ≥1% nuclear-stained cells, were expressed in 31%, and AR≥10% in 26% of patients. Median TIL content was: sTIL 19%, iTIL 5%, TIL in CT 5%, at IM 18%, sTIL in CT (CTs) 5%, iTIL in CT (CTi) 1%, sTIL at IM (IMs) 30%, and iTIL at IM (IMi) 5%. Prevalence of intermediate or high TIL content, defined as ≥10% was: CTs in 48%, CTi in 23%, IMs in 86%, and IMi in 47% of cases. In bivariable analysis all TIL indicators were significantly associated with longer OS, while AR was not. After adjustment for potential confounders using Cox proportional hazard regression, significant predictors of OS were sTIL (p0.007), IM TIL (p0.002), IMs (p0.001), and IMi (p0.030). In all cases higher TIL content was associated with longer OS. Although AR was not significant predictor of OS, it's interactions with TIL IMs and IMi was. There was no significant difference in OS between patients with high IMs and low IMs and AR0, but those with high IMs and AR≥1 had HR0.22 (p0.045) for death compared to patients with low IMs and AR0. Also, no difference for high IMi and low IMi and AR0, but patients with high IMi and AR≥1 had HR0.10 (p0.028) for death compared to patients with low IMi and AR0. Conclusions: Section analysis reveals frequent intermediate to high density and statistically significant prognostic impact of TIL on IM. That directs question towards role of different tumor compartments. Furthermore, combination of high expression of IMs and IMi with AR≥1 appears to be associated with longer OS than in patients with high IMs and IMi but with AR0. The correlations between AR and all TIL studied are extremely small, indicating their independence, but if so, their interaction in impact on OS is particularly interesting.

Impact of malnutrition and anemia at diagnosis in both: Pathological response and tumor-infiltrating-lymphocytes post neoadjuvant chemotherapy.

e12654 Background: The response after neoadjuvant chemotherapy (NAC) is the main prognostic factor in breast cancer (BC), likewise, malnutrition, anemia and systemic inflammation have also been associated to prognosis in breast cancer. We evaluated the association between pathological response (PR) and tumor infiltrating lymphocytes (TILs) post NAC with nutritional predictors as body mass index (BMI), prognostic nutritional index (PNI), anemia and neutrophil/lymphocyte index (N/L). Methods: This is a retrospective analysis of women diagnosed with BC between 2006 to 2017 at Instituto Nacional de Enfermedades (INEN) who received NAC. Pathological response was classified through residual cancer burden (RCB) and TILs post NAC which were prospectively evaluated by a pathologist. Clinical and pathological features as well as survival status were obtained from patient files. Results: We identified 439 women with BC who received NAC. Median age was 49 years, histological grade 3 was found in 245 patients (55.8%) and stage IIIB was the most frequent at diagnosis with 257 patients (58.5%). Luminal B subtype was the most frequent (43.7%). Rate of pCR was 10.5% and median TILs post NAC was 20%. About nutritional predictors, we use the median as a cutoff to discriminate between high and low values, for BMI was 27.5, for PNI was 56, for hemoglobin was 13.2 and for NLR was 1.84. There was no association for TILs post NAC with BMI (p = 0.38), PNI (p = 0.057) and hemoglobin (p = 0.43). We found a positive association between ILN and TILs post NAC (p = 0.001). On the other hand, we don’t found association for RCB with BMI (p = 0.45), PNI (p = 0.641), ILN (p = 0.2) and hemoglobin (p = 0.15). In the multivariate analysis, only RCB was an independent predictor for DFS (95 % CI, 87-100.5; p = 0.00001) and OS (95 % CI, 101.8-114.1; p = 0.00001). There was no association between BMI, PNI, ILN and anemia with OS and DFS. For the TILs post NAC there was a tendency to association with DFS (p = 0.07) and OS (p = 0.07). Conclusions: There are association between neutrophil/lymphocyte index with TILs after NAC. There was no association between nutritional and systemic predictors with long-term outcomes. The pathologic response is a biomarker for predicting the long-term outcomes of breast cancer patients.

Prognostic value of tumor-infiltrating lymphocyte subtypes in residual tumors of patients with triple-negative breast cancer after neoadjuvant chemotherapy.

Background:After neoadjuvant chemotherapy (NAC), non-pathological complete response of breast cancer patients can benefit from tailored adjuvant chemotherapy. However, it is difficult to select patients with poorer prognosis for additional adjuvant chemotherapy to maximize the benefits. Our study aimed to explore whether the subtypes of tumor-infiltrating lymphocytes (TILs) in residual tumors (RT) is related to the prognosis of triple-negative breast cancer (TNBC) after NAC.Methods:Data from patients with primary TNBC consecutively diagnosed at the Breast Disease Center of Peking University First Hospital from 2008 to 2014 were retrieved, and the cases with RT in the breast after NAC were enrolled. TILs subtypes in RT were observed by double-staining immunohistochemistry, and counted with the median TILs value per square millimeter as the cut-off to define high versus low TILs density in each subtype. The relationships between the TIL density of each subgroup and the clinicopathological characteristics of the RT after NAC patients were analyzed by Fisher exact test. Disease-free survival (DFS) and overall survival (OS) were analyzed by the Kaplan-Meier method and log-rank statistics.Results:A total of 37 eligible patients were included in this study, and the median follow-up period was 50 months (range 17–106 months). There was no significant correlation between the infiltrate density of CD4+, CD8+, CD20+, and CD68+ lymphocytes and clinic-pathological characteristics. Significantly better prognosis was observed in patients with high CD4+-TILs (DFS: P = 0.005, OS: P = 0.021) and high CD8+-TILs (DFS: P = 0.018) and low CD20+-TILs (OS: P = 0.042). Further analysis showed that patients with CD4+/CD20+ ratio greater than 1 (DFS: P = 0.001, OS: P = 0.002) or CD8+/CD20+ ratio greater than 1 (DFS: P = 0.009, OS: P = 0.022) had a better prognosis.Conclusions:Subtypes of TILs in RT is a potential predictive biomarker of survival in TNBC patients after NAC.

Tumor infiltrating lymphocytes (TIL) assessment in muscle invasive bladder cancer (MIBC) patients treated with cisplatin-based neoadjuvant chemotherapy (NAC) and surgery.

547 Background: Cisplatin-based NAC followed by surgery is the gold standard treatment of non-metastatic MIBC. However, predictive biomarkers have not been established yet. Here, we addressed the relevance of TILs for NAC response and prognosis in MIBC patients (pts). Methods: We conducted a single center, retrospective cohort analysis of consecutive MIBC pts treated with cisplatin-based NAC followed by surgery. Pts with pathological complete response (pCR; ypT0/isN0) were grouped as responders, pts with pathological residual disease as non responders. TIL stromal count were assessed pre- and post-NAC. Next Generation Sequencing of selected genes was performed on pre-NAC samples. We catalogued the 3-years(y) relapse free rate and 3-y overall survival rate (OS, Kaplan Meier) for the overall cohort and by subgroups. Results: Of the 25 pts who received cisplatin-gemcitabine NAC, a total of 14 (56%) pts achieved a pCR and 11 (44%) had residual disease. NAC was discontinued in 17 (65%) after completing treatment; and in 8 (32%) pts after 2 cycles due to toxicity. Median follow-up was 54.2 months(mos). At baseline, median TIL count was 60% in the overall cohort. Numerically higher TIL count was observed among responders (80%) compared to non-responders (50%) ( p=0.22). Median TIL count post-NAC in residual samples was 40%, not significantly different to matched pre-NAC samples ( p=0.93). Overall, 3-y relapse free rate was 74.7% (95%CI 51.7-87.9); 3-y OS rate was 79.6% (95%CI 57.6-91) with 6 deaths of which 4 were related to metastatic disease. Table reports subset analyses. Most frequently altered genes were PIK3CA and TP53 in the overall cohort (each 20%) and in the responders subgroup (each 29%). Conclusions: In our study, pts who achieved pCR had numerically greater TIL infiltrate in baseline samples and pCR was associated with reduced risk of recurrence. TILs did not increase in residual tumors after NAC. The independent predictive value of TILs warrants assessment in large cohorts.[Table: see text]

Abstract P5-06-14: Integrating CD8, FOXP3 and PD-L1 expression in prognostic models for triple negative breast cancer (TNBC): An analysis of 265 patients treated with standard therapy for stage I-III disease

Abstract Background: Tumor infiltrating lymphocytes (TILs) are strong prognostic biomarkers for early TNBC. We evaluated the role of CD8, FOXP3 and PD-L1 expression in refining prognostic models for non-metastatic TNBC in a large cohort of patients treated with standard therapy. Methods: Consecutive patients diagnosed with stage I-III TNBC (ER/PgR &amp;lt;10%, HER2 0/1+ or ISH non amplified) between May 2012 and December 2015 were included. All patients received treatment with surgery, chemotherapy (neoadjuvant or adjuvant) and radiotherapy (when indicated). For each case, three FFPE tumor slides were stained for CD8 (Clone C8/144B, Dako Cytomation), FOXP3 (Clone 236A/E7, dilution 1:200, Abcam) and PD-L1 (IHC 73-10 Research Use Only assay developed by Agilent Technologies). One slide was stained for cytokeratins with MNF116. Digital slides were evaluated by a Visiopharm® software application, following alignment of the CD8, FOXP3 and PD-L1 slides with the MNF116 slide. The density of CD8 and FOXP3 expression was calculated as the number of cells/mm2 of stroma area. For PD-L1, the % of positive stromal cells over the total of stromal cells was analyzed. Disease-free survival (DFS) was calculated from diagnosis to relapse or death. The Harrell’s c-index was used to determine the cut-offs for CD8, FOXP3 and PD-L1 to be used in survival analyses. Results: 265 TNBC pts were evaluated. Median TILs was 10% (Q1-Q3 3%-25%), median CD8 was 249 (Q1-Q3 109-568), median FOXP3 was 57 (Q1-Q3 21-134), median PD-L1 was 5.2% (Q1-Q3 0.2%-25.4%). TILs, CD8, FOXP3 and PD-L1 were positively correlated with each other (p&amp;lt;0.001): CD8 showed strong correlation with TILs (Spearman’s coefficient 0.753), FOXP3 and PD-L1 showed moderate correlation with TILs (Spearman’s coefficient 0.535 and 0.587). Higher TILs, CD8, FOXP3 and PD-L1 were associated with age ≤50yrs (p=0.002, p=0.004, p=0.065, p=0.011), Grade 3 (p=0.001, p=0.006, p=0.006, p=0.003) and Ki67 ≥30% (p=0.056, p=0.024, p=0.004, p=0.005). There was no association between immune markers and stage. Among classic clinicopathologic factors, TILs (10% increments) and stage at diagnosis were independent prognostic parameters in multivariate analysis (HR 0.81, 95% CI 0.69-0.94 p=0.005 for TILs, HR 2.01 95% ci 1.01-4.23 P=0.047 for stage II vs stage I and HR 5.31 95% CI 2.54-11.11 p&amp;lt;0.001 for stage III vs stage I). In univariate analysis, high CD8 (≥443), high FOXP3 (≥57) and high PD-L1 (&amp;gt;20%) were all significantly associated with improved DFS (HR 0.36 95%CI 0.18-0.72, p=0.004 for CD8; HR 0.48 95%CI 0.28-0.80, p=0.005 for FOXP3; HR 0.52 95%CI 0.28-0.97, p=0.039 for PD-L1). FOXP3 and PD-L1 provided significant additional prognostic information beyond a model containing TILs and stage: likelihood ratio χ2 5.12, p=0.024 for FOXP3; likelihood ratio χ2 5.52, p=0.019 for PD-L1. CD8 did not add relevant prognostic information beyond TILs and stage (likelihood ratio χ2 2.76, p=0.097). Including both FOXP3 and PD-L1 did not add further prognostic information to models already containing TILs, stage and either FOXP3 or PD-L1. Conclusions: FOXP3 and PD-L1 expression evaluated with a software-assisted method were prognostic for stage I-III TNBC pts treated with standard therapy and may contribute to refine the prognostic stratification beyond stage and TILs. This study was supported by a grant from Merck KGaA. Citation Format: Maria Vittoria Dieci, Vassilena Tsvetkova, Gaia Griguolo, Federica Miglietta, Deborah Bacchin, Giulia Tasca, Carlo Alberto Giorgi, Enrico Cumerlato, Enrico Orvieto, Valentina Guarneri, Pierfranco Conte. Integrating CD8, FOXP3 and PD-L1 expression in prognostic models for triple negative breast cancer (TNBC): An analysis of 265 patients treated with standard therapy for stage I-III disease [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-06-14.

Abstract PD5-03: Relationship between tumor-infiltrating lymphocytes (TILs) and outcomes in the KEYNOTE-119 study of pembrolizumab vs chemotherapy for previously treated metastatic triple-negative breast cancer (mTNBC)

Abstract Background: Several studies show that the presence of TILs has prognostic significance in TNBC, with greater lymphocytic infiltration associated with clinical outcomes. In the phase 2 KEYNOTE-086 study, TIL levels were a surrogate marker of preexisting antitumor immunity and were independent predictors of response to pembrolizumab (pembro) monotherapy. Here, we analyzed the relationship between the presence of TILs and outcomes in the phase 3 KEYNOTE-119 (NCT02555657) study of pembro monotherapy vs single-agent chemotherapy (chemo) in patients (pts) with previously treated mTNBC. Methods: From October 2015 to April 2017, 622 pts from 31 countries were enrolled. Key eligibility criteria included centrally confirmed TNBC, 1 or 2 prior systemic treatments for metastatic disease, documented progression on most recent therapy, prior treatment with an anthracycline and/or a taxane, and provision of a tumor sample for central determination of triple-negative status and PD-L1 expression. Pts with active brain metastases were excluded. Pts were stratified by PD-L1 status (positive vs negative; PD-L1 positivity was defined as a CPS ≥1) and history of prior neoadjuvant/adjuvant treatment vs de novo metastatic disease at initial diagnosis. Pts were randomly assigned 1:1 to pembro 200 mg Q3W or single-agent chemo per investigator’s choice of capecitabine, eribulin, gemcitabine, or vinorelbine, with a maximum enrollment cap of 60% for each, administered per local product label, until progression, intolerable toxicity, or investigator/patient decision. Response was assessed every 9 wk for 1 y and every 12 wk thereafter. Primary end points were OS in the PD-L1 CPS ≥10, CPS ≥1, and total populations. Secondary end points were PFS, ORR, duration of response, and DCR in the PD-L1 CPS ≥10, CPS ≥1, and total populations, and safety. The presence of TILs in archival tumor samples was assessed by light microscopy of hematoxylin and eosin-stained sections using a predefined method. The relationship between TILs and OS and PFS was analyzed using Cox regression; the relationship between TILs and ORR was analyzed using logistic regression. The interaction between treatment and TILs was assessed. Results: The study was negative for the primary end point. TILs were evaluable in 536/622 (86.2%) treated pts (273 [pembro]; 263 [chemo]). The median TILs distribution was 5% (IQR, 14%). TIL levels were significantly higher in responders vs nonresponders in the pembro arm, but not the chemo arm. TIL levels as a continuous variable were significantly (P&amp;lt; 0.05) associated with all clinical outcomes tested in the pembro but not the chemo arm (Table). For pts with TILs &amp;lt;5%, assessment of OS yielded a HR of 1.50 (95% CI, 1.14-1.97); for pts with TILs ≥5%, the HR was 0.75 (95% CI, 0.59-0.96). Median OS and 18-month OS rate (pembro vs chemo) for pts with TILs &amp;lt;5% was 5.9 vs 8.8 mo and 15% vs 27%, respectively; for pts with TILs ≥5%, this was 12.5 vs 11.3 mo and 35% vs 27%. The correlation between TILs vs CPS was moderate at 0.45; multivariate modeling of TILs and CPS showed independent predictive value. Conclusions: High TILs were significantly associated with better clinical outcomes with pembro but not chemo. Efficacy estimates at the prespecified median TIL cut point (≥5%) suggest that a subset of later-line advanced pts with TNBC can derive prolonged survival benefit from pembro over chemo. Association of TILs With Clinical OutcomesTreatment ArmContinuousBORDCRPFSOSVariableORRP*DCRP*Event RateP*Event RateP*Pembro (n=273),TILs25 (9.2)0.000732 (11.7)0.0058241 (88.3)0.0002239 (87.5)0.0001n (%)Chemo (n=263),TILs29 (11.0)0.180950 (19.0)0.3026191 (72.6)0.234236 (89.7)0.3321n (%)*P values are 1-sided for pembro and 2-sided for chemo.The stratification variable, prior (neo)adjuvant therapy vs de novo metastatic disease at initial diagnosis, was used as a covariate in the model.TILs was square root transformed.BOR, best overall response; chemo, chemotherapy; DCR, disease control rate; OS, overall survival; pembro, pembrolizumab; PFS, progression-free survival; TILs, tumor-infiltrating lymphocytes. Citation Format: Sherene Loi, Eric Winer, Oleg Lipatov, Seock-Ah Im, Anthony Goncalves, Javier Cortes, Keun S Lee, Peter Schmid, Laura Testa, Isabell Witzel, Shoichiro Ohtani, Nicholas Turner, Stefania Zambelli, Nadia Harbeck, Fabrice Andre, Rebecca Dent, LingKang Huang, Jaime Mejia, Vassiliki Karantza, Roberto Salgado. Relationship between tumor-infiltrating lymphocytes (TILs) and outcomes in the KEYNOTE-119 study of pembrolizumab vs chemotherapy for previously treated metastatic triple-negative breast cancer (mTNBC) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD5-03.

Abstract P1-10-20: Serial TILs: Evaluating the role of mid-treatment tumor infiltrating lymphocytes (TIL) in predicting pathologic complete response (pCR) in early-stage triple negative breast cancer (TNBC)

Abstract Introduction High levels of TIL at baseline are associated with higher pCR rates and better overall survival in TNBC. Recent studies have also indicated that higher TIL in post-NACT residual disease in TNBC are an important independent predictor of improved survival. We evaluated the role of mid-treatment (post-AC; Adriamycin/Cyclophosphamide) TIL in predicting pCR rates in early-stage TNBC. Methods Of 242 patients with stage I-III TNBC enrolled in the ARTEMIS trial (NCT02276443), 156 patients had pre-AC TIL and pCR status available for this analysis. Both pre-and post-AC TIL counts were available in 29 patients. Post-AC TIL counts for the remaining patients were imputed using linear regression with age, race, stage III, vimentin &amp;gt;50% and post-AC tumor volume reduction. Using these imputed TIL counts we evaluated the association of post-AC TIL with pCR. We also evaluated the change in TIL before and after treatment with AC. Results At baseline the median TIL count was 10% (n=156). In the post-AC samples, the median TIL count was 5%. Using imputed TIL counts, we did not conclude that post-AC TIL was associated with pCR (p= 0.28). Using a cut-point of 15% TIL, our analysis showed that baseline TIL is more strongly correlated with pCR than post-AC TIL (Table 1). In our univariable logistic regression, both baseline TIL and the difference in TIL pre-and post- treatment were significantly associated with pCR (p= 0.0015 and p=0.0068, respectively), however in the multivariable analysis only baseline TIL was significant. Our analysis did show that a decrease in TIL from pre- to post-treatment was significantly associated with pCR (p=0.022). However, this measure was not significant in our logistic regression model when pre-TIL was also included. Conclusion Higher pre-treatment TIL correlated more strongly with pCR rate when compared to post-AC TIL. Pre-treatment high TIL was associated with pCR regardless of changes in TIL pre and post treatment. Table 1. Changes in TIL before and after treatmentBaseline TILPost-AC TILN#pCR (%)LowLow6217 (27%)LowHigh4012 (30%)HighLow2513 (52%)HighHigh2916 (55%)TIL; Low: &amp;lt;15, High &amp;gt;15 Citation Format: Nour Abuhadra, Kenneth Hess, Jennifer Litton, Gaiane Rauch, Alastair Thompson, Bora Lim, Beatriz Adrada, Elizabeth Mittendorf, Senthil Damodaran, Rosalind Candelaria, Banu Arun, Wei Tse Yang, Naoto Ueno, Lumarie Santiago, Rashmi Murthy, Nuhad Ibrahim, Sahin Aysegul, William Symmans, Lei Huo, Stacy Moulder. Serial TILs: Evaluating the role of mid-treatment tumor infiltrating lymphocytes (TIL) in predicting pathologic complete response (pCR) in early-stage triple negative breast cancer (TNBC) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-10-20.

Abstract PD5-04: Tumor-infiltrating lymphocytes evaluation using machine learning image analysis based on core needle biopsy in HER2-positive breast cancer

Abstract Purpose: To evaluate tumor-infiltrating lymphocytes (TILs) quantitatively in breast cancer and to verify the utility of machine learning image analysis in TIL assessment. Methods: Stromal TILs in 105 Human epidermal growth factor receptor 2 (HER2)-positive invasive breast cancers, diagnosed from patients treated with neoadjuvant anti-HER2 therapy, were evaluated by image analysis of hematoxylin and eosin-stained slides from core needle biopsies. TIL level was determined as the number of TILs per square millimeter of stromal tissue. Associations of TIL level with clinicopathological parameters, pathological response, and clinical outcomes were assessed. Results: Median TIL level were 1287/mm2 (range, 123 - 8101/mm2). Higher TIL level was associated with higher histological grade (P = 0.02), estrogen receptor (ER) negativity (P = 0.036), and pathological complete response (pCR) (P&amp;lt; 0.0001). According to analysis of the receiver operating characteristic curve, a threshold TIL level of 2420/mm2 stroma best discriminated pCR from non-pCR. In multivariate analysis, high TIL levels (&amp;gt;2420/mm2) were significantly associated with pCR (P&amp;lt; 0.0001). On Kaplan-Meier analysis, prognosis was not associated with high or low TIL levels. However, high TIL levels tended to be associated with better prognosis in the HER2+/ER+ subgroup (P = 0.131), but not in the HER2+/ER- subgroup. Conclusions: A machine learning image analysis algorithm could assess TIL level as the number of TILs per square millimeter, contrary to semiquantitative evaluation. TIL level derived from this method could offer an independent predictor of pCR. Citation Format: Norie Abe, Hirofumi Matsumoto, Reika Takamatsu, Kentaro Tamaki, Naoko Takigami, Kanou Uehara, Yoshihiko Kamada, Nobumitsu Tamaki, Tokiwa Motonari, Norihiro Nakada, Hisamitsu Zaha, Naoki Yoshimi. Tumor-infiltrating lymphocytes evaluation using machine learning image analysis based on core needle biopsy in HER2-positive breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr PD5-04.

Quantitative digital image analysis of tumor-infiltrating lymphocytes in HER2-positive breast cancer.

As visual quantification of the density of tumor-infiltrating lymphocytes (TILs) lacks in precision, digital image analysis (DIA) approach has been applied in order to improve. In several studies, TIL density has been examined on hematoxylin and eosin (HE)-stained sections using DIA. The aim of the present study was to quantify TIL density on HE sections of core needle biopsies using DIA and investigate its association with clinicopathological parameters and pathological response to neoadjuvant chemotherapy in human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The study cohort comprised of patients with HER2-positive breast cancer, all treated with neoadjuvant anti-HER2 therapy. DIA software applying machine learning-based classification of epithelial and stromal elements was used to count TILs. TIL density was determined as the number of TILs per square millimeter of stromal tissue. Median TIL density was 1287/mm2 (range, 123-8101/mm2). A high TIL density was associated with higher histological grade (P = 0.02), estrogen receptor negativity (P = 0.036), and pathological complete response (pCR) (P < 0.0001). In analyses using receiver operating characteristic curves, a threshold TIL density of 2420/mm2 best discriminated pCR from non-pCR. In multivariate analysis, high TIL density (> 2420/mm2) was significantly associated with pCR (P < 0.0001). Our results indicate that DIA can assess TIL density quantitatively, machine learning-based classification algorithm allowing determination of TIL density as the number of TILs per unit area, and TIL density established by this method appears to be an independent predictor of pCR in HER2-positive breast cancer.