HER2-negative Group Research Articles

Abstract P2-03-04: Characteristics and clinical differences of breast cancer patients with negative or low HER2 expression

Abstract Background: High expression of HER2 receptor in Immunohistochemistry (IHC) sections or amplification of its gene in in situ hybridization (ISH) assays define a subset of breast cancers that have an aggressive natural history but respond to treatments blocking HER2. In contrast, patients with lower HER2 expression, not meeting the criteria for positivity, are currently treated similarly to completely HER2 negative patients. However, emerging data suggest that patients with low HER2 expression may derive benefit from newer antibody drug conjugates. Thus, this investigation sought to clarify the characteristics of HER2 low expressors and compare them with patients with no HER2 expression. Methods: We undertook a retrospective analysis of all breast cancer patients seen in our cancer center over a six-year period and classified as HER2 negative. Patients were categorized as HER2 negative when they had a score of 0 in IHC and as HER2 low if they had a score of 1+ or 2+ in IHC and no amplification by ISH. Characteristics of the patients and tumors in the two groups were compared. Results: A total of 391 HER2 negative and low patients have been included. Among them, 130 patients (33.2%) were HER2 negative (score 0 by IHC) and 261 patients (66.8%) were HER2 low (score 1+ and 2+ by IHC/ISH non-amplified). There were no differences in age, menopause status, mode of detection of cancer (clinical or screening) and clinical stage at diagnosis between the two groups. Patients in the HER2 low group had less commonly high-grade cancers than HER2 negative patients (25.35 versus 34.6%, x2 p=0.04).In addition, The HER2 low group had higher ER Histoscore (>240) in 88.1% of cases compared with 69.2% in HER2 negative group (x2 p<0.000). Similarly, a higher percentage of HER2 low cases than HER2 negative cases were expressing the progesterone receptor (PR, x2 p<0.000). HER2 low patients were rarely (3.8%) classified as triple negative, while this percentage was 21.5% in HER2 negative patients. Conclusion: HER2 negative staining (IHC score 0) is associated with averse tumor characteristics compared with clinically HER2 negative patients with low HER2 expression (score 1+ and 2+/ISH non-amplified). Citation Format: Ioannis Voutsadakis, Christopher Rosso. Characteristics and clinical differences of breast cancer patients with negative or low HER2 expression [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 P2-03-04.

HER2 Positivity Is Affected by the Papillary Structure and Has a Bidirectional Prognostic Value for Gallbladder Carcinoma.

Gallbladder carcinoma (GBC) is responsible for 80%–95% of biliary tract malignancies and has a dismal prognosis. Human epidermal growth factor receptor 2 (HER2) is a promising therapeutic target of GBC. Through immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) methods, HER2 expression and gene amplification were identified on high-output tissue microarrays (TMAs) developed in 306 GBC cases to investigate its relationship with GBC and clinicopathological characteristics. Adenocarcinomas accounted for 223 (72.9%) of the cases, with 62 (27.8%) being papillary adenocarcinoma or having partial papillary structure. HER2 positivity was studied in 16.1% (36/223) of patients with adenocarcinoma and 41.9% (26/62) in adenocarcinoma with papillary structures. For 143 radically resected primary GBC cases with 24 HER2-positive tumors, survival data were valid; the median survival time was not reached, and the 5-year survival rate was 52.9%. All patients in stages 0–I survived, and the results of the HER2-positive group and the stage II HER2-negative group were similar (p = 0.354). However, in stage III, the mortality rate in the HER2-positive group was reduced (p = 0.005) and that in stage IV was higher (p = 0.005). In conclusion, HER2 positivity was significantly higher in patients with papillary GBC. The predictive value of HER2 varies by clinical stage, with no prediction in the early stages, better in stage III, and worse in stage IV.

Quantitative Parameters of Diffusion Spectrum Imaging: HER2 Status Prediction in Patients With Breast Cancer.

ObjectiveTo explore the value of quantitative parameters derived from diffusion spectrum imaging (DSI) in preoperatively predicting human epidermal growth factor receptor 2 (HER2) status in patients with breast cancer.MethodsIn this prospective study, 114 and 56 female patients with invasive ductal carcinoma were consecutively included in a derivation cohort and an independent validation cohort, respectively. Each patient was categorized into HER2-positive or HER2-negative groups based on the pathologic result. All patients underwent DSI and conventional MRI including dynamic contrast-enhanced MRI (DCE-MRI) and diffusion-weighted imaging (DWI). The tumor size, type of the time-signal intensity curve (TIC) from DCE-MRI, apparent diffusion coefficient (ADC) from DWI, and quantitative parameters derived from DSI, including diffusion tensor imaging (DTI), diffusion kurtosis imaging (DKI), mean apparent propagator (MAP), and neurite orientation dispersion and density imaging (NODDI) of primary tumors, were measured and compared between the HER2-positive and HER2-negative groups in the derivation cohort. Univariable and multivariable logistic regression analyses were used to determine the potential independent predictors of HER2 status. The discriminative ability of quantitative parameters was assessed by receiver operating characteristic (ROC) curve analyses and validated in the independent cohort.ResultsIn the derivation cohort, the tumor size, TIC type, and ADC values did not differ between the HER2-positive and HER2-negative groups (p = 0.126–0.961). DSI quantitative parameters including axial kurtosis of DKI (DKI_AK), non-Gaussianity (MAP_NG), axial non-Gaussianity (MAP_NGAx), radial non-Gaussianity (MAP_NGRad), return-to-origin probability (MAP_RTOP), return-to-axis probability of MAP (MAP_RTAP), and intracellular volume fraction of NODDI (NODDI_ICVF) were lower in the HER2-positive group than in the HER2-negative group (p ≤ 0.001–0.035). DSI quantitative parameters including radial diffusivity (DTI_RD), mean diffusivity of DTI (DTI_MD), mean squared diffusion (MAP_MSD), and q-space inverse variance of MAP (MAP_QIV) were higher in the HER2-positive group than in the HER2-negative group (p = 0.016–0.049). The ROC analysis showed that the area under the curve (AUC) of ADC was 0.632 and 0.568, respectively, in the derivation and validation cohorts. The AUC values of DSI quantitative parameters ranged from 0.628 to 0.700 and from 0.673 to 0.721, respectively, in the derivation and validation cohorts. Logistic regression analysis showed that only NODDI_ICVF was an independent predictor of HER2 status (p = 0.001), with an AUC of 0.700 and 0.721, respectively, in the derivation and validation cohorts.ConclusionsDSI could be helpful for preoperative prediction of HER2, but DSI alone may not be sufficient in predicting HER2 status preoperatively in patients with breast cancer.

Molecular Classification of Gastric Cancer With Emphasis on PDL-1 Expression: The First Report From Iran.

Background:Gastric cancer is one of the lethal cancers and there is no effective treatment for these patients and still, 5-year survival rate is about 25% to 30%. Finding reliable biomarkers for early-stage diagnosis, targeted therapy, and survival prediction is a priority in this cancer.Objectives:In this study we were trying to know about the molecular classification of gastric cancers in a group of patients from the South of Iran.Patients and Methods:In a cross sectional study, 50 specimens of gastric cancer were selected that have enough tissue to be stained by immunohistochemistry (IHC). IHC was performed for Her-2, mismatch repair genes (MLH-1, MSH-2, MSH-6, and PMS-2), and PDL-1. Frequency of positive makers was compared with survival and outcome.Results and Conclusion:In our study, deficient MMR (dMMR) was detected in 4 patients (8.0%). PD-L1 expression in tumor cells (TC) was observed in 1 of 4 cases (25%) with PMS2 loss. However, PD-L1 in TCs and TILs (tumor infiltrating lymphocytes) was negative in 1 case with MLH1 loss and in 3 of 4 cases with PMS2 loss, which was not statistically significant. All of our 50 cases were positive for MSH2 and MSH6, 24% of which showed TCs with PDL-1 expression and 32% of them in TIL. HER2 was positive in 2 (2/50, 4.0%) cases, among which all of the cases were positive for PD-L1 expression in TCs and TILs, respectively. However, in HER2-negative group, 26.2% (11/42) and 28.6% (12/42) of tumors were positive for PD-L1 in TCs and TILs, respectively. The expression rate of PD-L1 in HER2 negative TCs was significantly higher than that in HER2 positive TCs (P = .033). Immunohistochemistry for Her-2 was equivocal in 6 cases (12.0%) none of which expressed PD-L1 in tumor cells. In our study minimum and maximum survival times from detection of gastric cancer were 1 and 87 months, respectively. The mean ± SD and median ± SD of overall survival time were 30.69 ± 4.88 and 18 ± 1.45 months, respectively. One and 3-year survival rates of 40% and 24%, respectively. PD-L1 expression was not associated with survival, but its expression was associated with intestinal type Lauren classification and negative HER-2. PD-L1 positivity in tumor cells or tumor infiltrating lymphocytes was not an independent prognostic factor in gastric cancer.

Efficacy and Safety of Bevacizumab in Pretreated Metastatic Breast Cancer: A Systematic Review and Meta-Analysis.

The use of bevacizumab in patients with previously treated metastatic breast cancer (MBC) is controversial. This meta-analysis was carried out to evaluate the efficacy and safety of the regimen including bevacizumab among patients with pretreated MBC. We systematically searched PubMed, the Cochrane Library, Web of Science, and Embase databases for randomized controlled trials evaluating bevacizumab combined with chemotherapy for previously treated MBC patients. The primary endpoints were progression-free survival (PFS) and objective response rate (ORR). The secondary endpoints were overall survival (OS) and toxicity. The risk of bias was assessed by the Cochrane Collaboration's tool. The pooled hazard ratio (HR) and risk ratio (RR) with 95% confidence intervals (CIs) were calculated for the identified studies. This study was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Four studies involving 1,640 individuals were included. Pooling results showed that the PFS of bevacizumab-containing groups (HR 0.82; 95% CI 0.73-0.93, p = 0.002) was significantly better than that of the control groups, especially when bevacizumab was administered as the second-line treatment for patients with human epidermal growth factor receptor 2 (HER2)-negative MBC (HR 0.77; 95% CI 0.66-0.88, p = 0.0002). The ORR in the bevacizumab-containing group was superior to that in the control group, both in the general (RR 1.45; 95% CI 1.18-1.78, p = 0.0004) and HER2-negative groups (RR 1.30; 95% CI 1.03-1.63, p = 0.03). However, no significant effect on OS was demonstrated for the addition of bevacizumab to the second-line treatment for HER2-negative MBC (HR 0.93; 95% CI 0.79-1.10, p = 0.39). Comparatively, proteinuria was more common in the bevacizumab-containing group. In addition, the application of bevacizumab tended to result in therapy discontinuation due to treatment-related toxicity. Bevacizumab-containing chemotherapy, in light of its favorable effects on clinical outcomes, could be a preferred therapeutic option for patients with MBC, for whom the disease must be rapidly relieved. Further studies are warranted for exploring the advantageous patients with the receipt of bevacizumab in multiline treatment.

Residual cancer burden after neoadjuvant chemotherapy and long-term survival outcomes in breast cancer: a multicentre pooled analysis of 5161 patients.

SummaryBackgroundPrevious studies have independently validated the prognostic relevance of residual cancer burden (RCB) after neoadjuvant chemotherapy. We used results from several independent cohorts in a pooled patient-level analysis to evaluate the relationship of RCB with long-term prognosis across different phenotypic subtypes of breast cancer, to assess generalisability in a broad range of practice settings.MethodsIn this pooled analysis, 12 institutes and trials in Europe and the USA were identified by personal communications with site investigators. We obtained participant-level RCB results, and data on clinical and pathological stage, tumour subtype and grade, and treatment and follow-up in November, 2019, from patients (aged ≥18 years) with primary stage I–III breast cancer treated with neoadjuvant chemotherapy followed by surgery. We assessed the association between the continuous RCB score and the primary study outcome, event-free survival, using mixed-effects Cox models with the incorporation of random RCB and cohort effects to account for between-study heterogeneity, and stratification to account for differences in baseline hazard across cancer subtypes defined by hormone receptor status and HER2 status. The association was further evaluated within each breast cancer subtype in multivariable analyses incorporating random RCB and cohort effects and adjustments for age and pretreatment clinical T category, nodal status, and tumour grade. Kaplan-Meier estimates of event-free survival at 3, 5, and 10 years were computed for each RCB class within each subtype.FindingsWe analysed participant-level data from 5161 patients treated with neoadjuvant chemotherapy between Sept 12, 1994, and Feb 11, 2019. Median age was 49 years (IQR 20–80). 1164 event-free survival events occurred during follow-up (median follow-up 56 months [IQR 0–186]). RCB score was prognostic within each breast cancer subtype, with higher RCB score significantly associated with worse event-free survival. The univariable hazard ratio (HR) associated with one unit increase in RCB ranged from 1·55 (95% CI 1·41–1·71) for hormone receptor-positive, HER2-negative patients to 2·16 (1·79–2·61) for the hormone receptor-negative, HER2-positive group (with or without HER2-targeted therapy; p<0·0001 for all subtypes). RCB score remained prognostic for event-free survival in multivariable models adjusted for age, grade, T category, and nodal status at baseline: the adjusted HR ranged from 1·52 (1·36–1·69) in the hormone receptor-positive, HER2-negative group to 2·09 (1·73–2·53) in the hormone receptor-negative, HER2-positive group (p<0·0001 for all subtypes).InterpretationRCB score and class were independently prognostic in all subtypes of breast cancer, and generalisable to multiple practice settings. Although variability in hormone receptor subtype definitions and treatment across patients are likely to affect prognostic performance, the association we observed between RCB and a patient’s residual risk suggests that prospective evaluation of RCB could be considered to become part of standard pathology reporting after neoadjuvant therapy.

PROFILE OF SURROGATE MARKERS OF MOLECULAR SUBTYPES USING THE EXPRESSION PATTERN OF ER, PR, AND HER2/NEU RECEPTORS IN OPERABLE BREAST CANCER

Objective: The present study was planned with an aim to study the profile of surrogate markers of molecular subtypes using the expression pattern of ER, PR, and HER2/NEU receptors in operable breast cancer so that most effective and advantageous treatment can be offered for better surgical outcomes. Methods: A cross-sectional observational study was carried out in one of the tertiary care centers in Central UP. All patients presenting to the center with early and locally advanced breast cancer with age bracket between 18 and 75 years during 2-year period and willing to participate in the study were included in the sample size. Clinical staging was done using the standard TNM criteria and all the specimens were subjected to immunohistochemical evaluation for surrogate molecular subtyping Results: Out of 94 cases enrolled in the study, a total of 32 (34.4%) were identified as luminal A, 3 (3.2%) were identified as luminal B, 35 (37.6%) were identified as HER2 positive, and remaining 23 (24.7%) were identified as triple negative. Statistically, there was no significant difference among groups with respect to age (p=0.958) and BMI (p=0.332). However, there was a significant difference among groups with respect to clinical stage (p=0.031), clinical nodal involvement (p=0.014), pathological staging (p=0.006), and pathological nodal involvement (p=0.023). Among those with nodal involvement, all the cases had involvement of one node except for one patient in Group I who had involvement of thrMost of the luminal A cases (81.3%) were clinically Stage 1 or 2. All the luminal B cases were clinically Stage 2 or 3 (100%). Almost half (48.8%) of Her2-negative cases were Stage 3 or 4. Majority of triple-negative cases were Stage 3 or 4 (65.2%). Clinically, nodal involvement was seen to be maximum in Her2-negative and triple-negative groups (54.3% and 52.2% of cases, respectively). Pathologically, most of the luminal A (83.9%), Her2 negative (81.8%), and all the luminal B cases were Stage 2. Pathologically, nodal involvement was seen in 16.1% of luminal A, 42.4% of Her2-negative, and 50% of triple-negative cases. Conclusion: The findings of the present study provided a glimpse of expression pattern of ER, PR, and HER2/NEU receptors in operable breast cancer based on which most effective and advantageous treatment can be offered for better surgical outcomes.

Clinical characteristics and disease outcomes in ER+ breast cancer: a comparison between HER2+ patients treated with trastuzumab and HER2- patients

BackgroundTrastuzumab has changed the prognosis of HER2+ breast cancer. We aimed to investigate the prognosis of ER+/HER2+ patients treated with trastuzumab, thus to guide escalation endocrine treatment in ER+ breast cancer.MethodsER-positive early breast cancer patients operated at Ruijin Hospital between Jan. 2009 and Dec. 2017 were retrospectively included. Eligible patients were grouped as HER2-negative (HER2-neg) or HER2-positive with trastuzumab treatment (HER2-pos-T). Kaplan-Meier analysis and Cox proportional hazards model were used to compare the disease-free survival (DFS) and overall survival (OS) between these two groups.ResultsA total of 3761 patients were enrolled: 3313 in the HER2-neg group and 448 in the HER2-pos-T group. Patients in the HER2-pos-T group were associated with pre/peri-menopause, higher histological grade, LVI, higher Ki-67 level, lower ER and PR levels (all P < 0.05). At a median follow-up of 62 months, 443 DFS events and 191 deaths were observed. The estimated 5-year DFS rate was 89.7% in the HER2-neg group and 90.2% in the HER2-pos-T group (P = 0.185), respectively. Multivariable analysis demonstrated that patients in the HER2-pos-T group had a better DFS than patients in the HER2-neg group (HR 0.52, 95% CI: 0.37–0.73, P < 0.001). The estimated 5-year OS rates were 96.0% and 96.3% in the two groups, respectively (P = 0.133). Multivariate analysis found that HER2-pos-T group was still associated with significantly better OS compared with the HER2-neg group (HR 0.38, 95% CI: 0.22–0.67, P = 0.037).ConclusionER+/HER2+ breast cancer patients treated with trastuzumab were associated with superior outcome compared with ER+/HER2- patients, indicating HER2-positivity itself may not be an adverse factor for ER+ patients in the era of trastuzumab.

Abstract 257: Tumor mutation burden of Egyptian breast cancer patients based on next generation sequencing

Abstract Tumor mutation burden of Egyptian breast cancer patients based on next generation sequencing Aim: This study aimed to identify the tumor mutation burden (TMB) value in Egyptian Breast cancer (BC) patients. Additionally, we aimed to find the best model to predict TMB value by the expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER-2), and proliferative index Ki-67, to help expecting the prognosis of patients and predicting the possible response to immunotherapy. Patients and methods: In 58 Egyptian patients with BC, the Ion AmpliSeq Comprehensive Cancer Panel based on NGS was used to determine the TMB value of primary tumor tissues of Egyptian BC patients. The predicted TMB value was divided into 4 groups: A (0.00-0.625), B (0.626-1.25), C (1.251-2.50), and D (&amp;gt;2.50), according to the quartile method, with group A as reference level. Different machine learning models were used to select the optimal classification model. Results: The measured TMB value was between 0 and 8.12/Mb. The TMB distribution among the studied 58 cases was: 19 cases in group A, 12 cases in group B, 14 cases in group C, and 13 cases in group D. ER positive expression was significantly associated with TMB ≤ 1.25 (ER positive vs ER-negative, OR =0.35, 95% CI: 0.04-2.98, p= 0.001). TMB ≤1.25 was significantly distributed in patients with PR positive expression (PR positive versus PR negative, OR = 0.17, 95% CI= 0.02-0.44, p= 0.002). Ki67 expression positive was significantly associated with TMB &amp;gt;1.25 than those who were Ki-67 expression negative (Ki67 positive versus Ki67 negative, OR = 9.33, 95% CI= 2.07-42.18, p= 0.004). Also, TMB &amp;gt;1.25 was significantly distributed in triple negative (TN) patients than non-TN patients (OR=9.69, 95% CI: 1.05-89.9, p=0.045). However, no significant differences were observed between HER2 positive and HER2 negative group (OR = 2.47, 95% CI: 0.64-9.54, p =0.19). The adjusted Pseudo-R2 was 0.329 (P&amp;lt;0.001). The optimized logistic regression model was TMB = -27.5 -1.82 ER - 0.73 PR + 0.826 HER2 + 2.08 Ki67. Conclusion: the preliminary findings of our studied sample set revealed that level of TMB in Egyptian BC patients is relatively low. Also, TMB value in hormone receptor positive and Ki-67 expression positive Egyptian BC patients is higher than hormone receptor negative and Ki-67 expression negative patients. Moreover, TMB value can be predicted based on the expression level of ER, PR, HER-2, and Ki-67. The optimized logistic regression model was TMB = -27.5 -1.82 ER - 0.73 PR + 0.826 HER2 + 2.08 Ki67. Citation Format: Auhood Nassar, Ahmed M. Lymona, Mai M. Lotfy, Amira Salah El-Din Youssef, Abdel-Rahman N. Zekri. Tumor mutation burden of Egyptian breast cancer patients based on next generation sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 257.

Tumor Mutation Burden Prediction Model in Egyptian Breast Cancer patients based on Next Generation Sequencing.

Objectives:This study aimed to identify the tumor mutation burden (TMB) value in Egyptian breast cancer (BC) patients. Moreover, to find the best TMB prediction model based on the expression of estrogen (ER), progesterone (PR), human epidermal growth factor receptor 2 (HER-2), and proliferation index Ki-67. Methods:The Ion AmpliSeq Comprehensive Cancer Panel was used to determine TMB value of 58 Egyptian BC tumor tissues. Different machine learning models were used to select the optimal classification model for prediction of TMB level according to patient’s receptor status. Results:The measured TMB value was between 0 and 8.12/Mb. Positive expression of ER and PR was significantly associated with TMB ≤ 1.25 [(OR =0.35, 95% CI: 0.04–2.98), (OR = 0.17, 95% CI= 0.02-0.44)] respectively. Ki-67 expression positive was significantly associated with TMB >1.25 than those who were Ki-67 expression negative (OR = 9.33, 95% CI= 2.07-42.18). However, no significant differences were observed between HER2 positive and HER2 negative groups. The optimized logistic regression model was TMB = -27.5 -1.82 ER – 0.73 PR + 0.826 HER2 + 2.08 Ki-67. Conclusion:Our findings revealed that TMB value can be predicted based on the expression level of ER, PR, HER-2, and Ki-67.

TIMAP Upregulation Correlates Negatively with Survival in HER2- Negative Subtypes of Breast Cancer.

Objective:TIMAP expression is regulated by transforming growth factor beta 1 (TGFβ1); known for its role in breast cancer development and metastasis. Nevertheless, data on TIMAP protein expression and its association with breast cancer development are lacking. In this study, we aimed to investigate the variation in TIMAP protein expression in breast cancer tissue and its correlation with various clinicopathological characteristics of breast cancer patients and overall survival rate. Methods:A total of 159 paraffin-embedded tissue blocks from women diagnosed with four breast cancer subtypes (49 HER2-only, 33 Luminal A, 39 Luminal B, and 38 triple negative) were used to construct tissue microarray (TMA), followed by TIMAP immunohistochemistry (IHC). TIMAP expression was scored by two pathologists and categorized as weak (1-33% expression), moderate (34-66%), and strong (67-100%). Chi-square test and Kaplan Meier survival test were performed to determine the association between TIMAP expression and clinicopathological features and overall survival rate, respectively. Results:TIMAP protein was strongly expressed in 46 (93.9%) HER2-only, 32 (97%) luminal A, 37 (94.9%) luminal B, and 29 (76.3%) triple negative. TIMAP expression negatively associated with ER/PR expression (P=0.03), and it negatively impacted the overall survival in HER2 negative group (P=0.02). Conclusion:Our findings suggest that TIMAP protein expression is upregulated in all breast cancer subtypes. However, its prognostic role is exclusively observed in HER2- negative group, suggesting a potential of targeting TIMAP in future therapeutic strategies in this group.

The Prognostic Impact of HER2 Genetic and Protein Expression in Pancreatic Carcinoma-HER2 Protein and Gene in Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal and clinically heterogeneous disease with a limited benefit from human epidermal growth factor receptor 2 (HER2)-targeted therapy. Recently, some studies have addressed the antitumoral effect of novel anti-HER2 drugs in HER2 low-expressing tumors. However, there have been few studies on the significance of low HER2 expression and genetic heterogeneity in PDAC. Using immunohistochemistry and dual-color silver-enhanced in situ hybridization based on the Trastuzumab for a gastric cancer scoring scheme, we evaluated HER2 protein expression, gene amplification, and genetic heterogeneity in three groups (HER2-neg, HER2-low, HER2-pos) of 55 patients. Among the 55 cases, 41.8% (23/55) showed HER2 expression of any intensity. HER2 amplification independent of HER2 expression was 25.5% (14/55). Patients in both these groups had a shorter overall survival than did patients in the HER2-neg group. HER2 genetic heterogeneity was identified in 37 (70.9%) of the 55 cases, mainly in HER2-neg and HER2-low groups. HER2 genetic heterogeneity significantly correlated with worse survival in the HER2-low and HER2-neg groups of PDAC. These findings support the hypothesis that low-level HER2 expression and heterogeneity have significant clinical implications in PDAC. HER2 heterogeneity might indicate the best strategies of combination therapies to prevent the development of subdominant clones with resistance potential.

HER2 testing in breast cancers: comparison of assays and interpretation using ASCO/CAP 2013 and 2018 guidelines.

HER2 overexpression and gene amplification are routinely tested by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH), respectively. In addition, HER2 mRNA expression is also tested by the Oncotype DX assay. Discordance between laboratories among the different assays remains a problem. To improve the routine HER2 reporting, the American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) updated their guidelines in 2018. Our study will compare concordance of HER2 status by IHC and FISH using ASCO/CAP 2013 and 2018 guidelines with Oncotype DX. We retrospectively reviewed 657 estrogen receptor positive primary breast cancer cases with available Oncotype DX tests between 2011 and 2018. Medical records were reviewed for HER2 results by IHC, FISH, and Oncotype DX. The HER2 results by different assays and between 2013 and 2018 guidelines were compared. Of the 657 cases, 280 were tested by IHC, FISH, and Oncotype DX. HER2-equivocal cases by IHC 2013 guidelines were all negative (67/67, 100%) by FISH 2018 guidelines and by Oncotype DX. HER2-equivocal cases by FISH 2013 guidelines were all negative (16/16, 100%) by FISH 2018 guidelines, while 15/16 (93.8%) negative and 1/16 (6.2%) equivocal by Oncotype DX. The HER2-equivocal and HER2-negative groups were similar in age, gender, histology, grade, and Ki67 score. HER2 concordance was highest between Oncotype DX (99.6%) and FISH per 2018 guidelines. This suggests that the ASCO/CAP 2018 guidelines improved the accurate stratification of HER2-equivocal cases.

Fatty Acid Synthase Confers Tamoxifen Resistance to ER+/HER2+ Breast Cancer.

Simple SummaryOveractivation of the human epidermal growth factor receptor 2 (HER2) is one of the main drivers of tamoxifen resistance in estrogen receptor (ER)-positive breast cancer patients. Combined targeting of HER2 and ER, however, has yielded disappointing results in the clinical setting. Therefore, other potential mechanisms for tamoxifen resistance would not be overcome by solely blocking the cross-talk between ER and HER2 at the receptor(s) level. Using cell lines, animal models, and clinical data, we provide evidence to support a critical role of fatty acid synthase (FASN)—the major site for endogenous fat synthesis—in HER2-driven tamoxifen resistance. Importantly, treatment with a FASN inhibitor impeded the estrogen-like tumor-promoting effects of tamoxifen and fully restored the anti-estrogenic activity of tamoxifen in ER+/HER2-overexpressing breast cancer xenografts. We postulate FASN as a biological determinant of HER2-driven tamoxifen resistance and FASN inhibition as a novel therapeutic approach to restore tamoxifen sensitivity in endocrine-resistant breast cancer.The identification of clinically important molecular mechanisms driving endocrine resistance is a priority in estrogen receptor-positive (ER+) breast cancer. Although both genomic and non-genomic cross-talk between the ER and growth factor receptors such as human epidermal growth factor receptor 2 (HER2) has frequently been associated with both experimental and clinical endocrine therapy resistance, combined targeting of ER and HER2 has failed to improve overall survival in endocrine non-responsive disease. Herein, we questioned the role of fatty acid synthase (FASN), a lipogenic enzyme linked to HER2-driven breast cancer aggressiveness, in the development and maintenance of hormone-independent growth and resistance to anti-estrogens in ER/HER2-positive (ER+/HER2+) breast cancer. The stimulatory effects of estradiol on FASN gene promoter activity and protein expression were blunted by anti-estrogens in endocrine-responsive breast cancer cells. Conversely, an AKT/MAPK-related constitutive hyperactivation of FASN gene promoter activity was unaltered in response to estradiol in non-endocrine responsive ER+/HER2+ breast cancer cells, and could be further enhanced by tamoxifen. Pharmacological blockade with structurally and mechanistically unrelated FASN inhibitors fully impeded the strong stimulatory activity of tamoxifen on the soft-agar colony forming capacity—an in vitro metric of tumorigenicity—of ER+/HER2+ breast cancer cells. In vivo treatment with a FASN inhibitor completely prevented the agonistic tumor-promoting activity of tamoxifen and fully restored its estrogen antagonist properties against ER/HER2-positive xenograft tumors in mice. Functional cancer proteomic data from The Cancer Proteome Atlas (TCPA) revealed that the ER+/HER2+ subtype was the highest FASN protein expressor compared to basal-like, HER2-enriched, and ER+/HER2-negative breast cancer groups. FASN is a biological determinant of HER2-driven endocrine resistance in ER+ breast cancer. Next-generation, clinical-grade FASN inhibitors may be therapeutically relevant to countering resistance to tamoxifen in FASN-overexpressing ER+/HER2+ breast carcinomas.

Dual-energy CT quantitative parameters for evaluating Immunohistochemical biomarkers of invasive breast cancer

BackgroundEstrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and Ki67 are the most useful immunohistochemical biomarkers of invasive breast cancer. The purpose of this study is to investigate the possibility of quantitative parameters derived from dual-energy CT (DECT) to discriminate immunohistochemical biomarkers of invasive breast cancer.MethodsThis prospective study enrolled 120 patients with invasive breast cancer who underwent preoperative contrast-enhanced DECT for staging purposes from June 2019 to January 2020. DECT quantitative parameters, including normalized iodine concentration (NIC), the slope of the spectral Hounsfield unit curve (λHu), and the normalized effective atomic number (nZeff), were obtained from reconstructed images. DECT quantitative parameters were compared with the expression status, and the correlations with the value of immunohistochemical biomarkers were evaluated. Inter-observer reproducibility analysis was performed to assess the measurement reproducibility of quantitative parameters. The diagnostic performance of the quantitative parameters was analyzed by receiver operating characteristic curve.ResultsThe ER-negative group tended to display higher venous phase NIC and nZeff compared with the ER-positive group (individually, p = 0.003, 0.011; area under the curve [AUC] of 0.65, 0.60). The PR-negative group demonstrated higher arterial and venous phase NIC compared with the PR-positive group (individually, p = 0.022, 0.005; AUC of 0.63, 0.65). NIC was correlated negatively with the value of ER and PR expression (r = − 0.175 ~ − 0.265, p = 0.002 ~ 0.042). The HER2-positive group tended to display higher venous phase nZeff than the HER2-negative group (p = 0.022; AUC of 0.59). The Ki67 high-proliferation group demonstrated higher arterial phase, venous phase NIC and nZeff than the Ki67 low-proliferation group (p < 0.001 ~ 0.005; AUC of 0.67 ~ 0.75). Both the NIC and nZeff were correlated positively with the value of Ki67 (r = 0.240 ~ 0.490, p < 0.001 ~ 0.014).ConclusionsNIC and nZeff derived from DECT could be used to discriminate expression status and may associate with the value of immunohistochemical biomarkers of invasive breast cancer.

Clinical significance of HER2 status in T1bN0 breast cancer: a nationwide study from the Korean Breast Cancer Society.

The prognosis of patients with node-negative T1b tumors according to human epidermal growth factor receptor 2 (HER2) status is not known. This group of patients has not been studied in the available randomized trials. The objective of this study was to evaluate the survival of patients in a monoethnic group diagnosed with T1b lymph node-negative breast cancer depending on HER2 status. We analyzed 3110 patients with T1bN0M0 breast cancer whose data were deposited into the Korean Breast Cancer Society Registry database between 2000 and 2009. Overall survival (OS) and breast cancer-specific survival (BCSS) were compared according to HER2 status. Among all patients, 494 (15.9%) had HER2-positive breast cancer. At a mean follow-up of 93months, 108 deaths and 86 breast cancer-specific deaths were noted among all patients. There was no significant difference in OS between the HER2-negative and HER2-positive groups (p = 0.103). The same result was observed for BCSS. However, in the subgroup of estrogen receptor (ER)-positive women, HER2-negative patients had a better BCSS prognosis than HER2-positive patients (p = 0.025). Multivariate analysis also indicated a significant difference in BCSS in the ER-positive subgroup (HR 2.60; 95% CI 1.15-5.87; p = 0.021). This study analyzed a large nationwide and monoethnic cohort and found a significant difference only in BCSS in the ER-positive subgroup according to HER2 status. Anti-HER2 therapy may be considered in HER2-positive and ER-positive patients with small, node-negative breast cancer.

18F-FDG PET/CT metabolic parameters and HER2 expression in colorectal cancer.

The relationship between 18F-FDG uptake and HER2 expression in colorectal cancer has not been investigated yet. This study aimed to investigate the predictive efficiency of preoperative 18F-FDG PET/CT for HER2 expression and prognosis in colorectal cancer. We retrospectively analyzed 131 colorectal cancer patients who underwent 18F-FDG PET/CT scans in our center before surgery. HER2 positivity was defined as a score of 2+ or 3+, and HER2 negativity was defined as a score of 0 or 1+ in immunohistochemistry of HER2 expression. The relationships between 18F-FDG PET/CT metabolic parameters and HER2 expression and the prognosis of colorectal patients were systematically studied. From 131 colorectal cancer patients, there were 27 (20.6%) HER2-positive patients. SUVmax of the primary tumor (mean ± SD) in the HER2-positive and the HER2-negative group was 18.238±8.912 and 14.455±6.531, respectively. SUVmax in the HER2-positive group was higher than in the negative group (p=0.034). When the cutoff was based on 5 cm, tumor size demonstrated significant positive correlations with SUVmax (p=0.012) and HER2 expression (p=0.014). Multivariate analysis showed that both SUVmax and tumor size had a significant correlation with HER2 expression (p=0.049 vs. p=0.043, respectively). There was no statistical difference in PFS between the HER2-positive and the HER2-negative group (p=0.28). 18F-FDG metabolic parameters had a significant correlation with HER2 expression in colorectal cancer. SUVmax combined with primary tumor size were better for predicting the HER2 status of colorectal cancer. 18F-FDG metabolic parameters had a significant correlation with HER2 expression in colorectal cancer. SUVmax combined with primary tumor size were better for predicting the HER2 status of colorectal cancer.

JAK2 expression is correlated with the molecular and clinical features of breast cancer as a favorable prognostic factor

Janus kinases are a family of non-receptor tyrosine kinases involved in autoimmune diseases and malignancies. In breast cancer, the immune related role of JAK2 remains unclear. We aimed to investigate its role at transcriptome level and its relationship with the clinical outcome of breast cancer. This study enrolled a total of 2994 breast cancer samples with transcriptome data, including 1090 samples from The Cancer Genome Atlas (TCGA) and 1904 from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC). JAK2 expression was significantly upregulated in both PR positive group (P < 0.01) and HER2 negative group (P < 0.01), and was correlated with American Joint Committee on Cancer (AJCC) stage and tumor malignancies of breast cancer. Functional enrichment analysis revealed that genes correlated with JAK2 were mainly involved in essential functions associated with immune response. Intriguingly, we investigated the association between JAK2 and immune modulators in pan-cancer, JAK2 expression was positively correlated with most of these immune modulators. In clinical aspect, higher expression of JAK2 was an independent indicator of favorable prognosis in breast cancer patients. The expression of JAK2 is tightly related to the pathology and molecular pathology of breast cancer, and synergistic with other checkpoint members thereby playing a specific role in regulating tumor immune microenvironment. To our knowledge, this is the largest and most comprehensive study characterizing the expression pattern of JAK2 and its special immune functions together with its prognostic values in breast cancer. These findings might shed novel sights for future research in cancer immunotherapy by targeting immune checkpoint molecules.

Early prediction of neoadjuvant chemotherapy response for advanced breast cancer using PET/MRI image deep learning

This study aimed to investigate the predictive efficacy of positron emission tomography/computed tomography (PET/CT) and magnetic resonance imaging (MRI) for the pathological response of advanced breast cancer to neoadjuvant chemotherapy (NAC). The breast PET/MRI image deep learning model was introduced and compared with the conventional methods. PET/CT and MRI parameters were evaluated before and after the first NAC cycle in patients with advanced breast cancer [n = 56; all women; median age, 49 (range 26–66) years]. The maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were obtained with the corresponding baseline values (SUV0, MTV0, and TLG0, respectively) and interim PET images (SUV1, MTV1, and TLG1, respectively). Mean apparent diffusion coefficients were obtained from baseline and interim diffusion MR images (ADC0 and ADC1, respectively). The differences between the baseline and interim parameters were measured (ΔSUV, ΔMTV, ΔTLG, and ΔADC). Subgroup analysis was performed for the HER2-negative and triple-negative groups. Datasets for convolutional neural network (CNN), assigned as training (80%) and test datasets (20%), were cropped from the baseline (PET0, MRI0) and interim (PET1, MRI1) images. Histopathologic responses were assessed using the Miller and Payne system, after three cycles of chemotherapy. Receiver operating characteristic curve analysis was used to assess the performance of the differentiating responders and non-responders. There were six responders (11%) and 50 non-responders (89%). The area under the curve (AUC) was the highest for ΔSUV at 0.805 (95% CI 0.677–0.899). The AUC was the highest for ΔSUV at 0.879 (95% CI 0.722–0.965) for the HER2-negative subtype. AUC improved following CNN application (SUV0:PET0 = 0.652:0.886, SUV1:PET1 = 0.687:0.980, and ADC1:MRI1 = 0.537:0.701), except for ADC0 (ADC0:MRI0 = 0.703:0.602). PET/MRI image deep learning model can predict pathological responses to NAC in patients with advanced breast cancer.

Correlation between HER2 expression before neoadjuvant treatment and RCB classification after surgical treatment in breast cancer

Objective: To explore the relationship between the expression of human epidermal growth factor receptor 2 (HER2) in core needle biopsy (CNB) specimens before neoadjuvant chemotherapy (NAC) and post NAC Residual Cancer Burden (RCB) classification in breast cancer. Methods: This retrospective study included 150 patients with CNB proven invasive breast carcinoma in the Fourth Hospital of Hebei Medical University from January 2013 to January 2014. Immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH) was used to detect the expression of HER2 in the CNB specimens. RCB was used to assess the chemotherapy response of patients. SPSS 21.00 and GraphPad Prism 8.0.1 were used for data statistics; Chi square test and Fisher's exact test for correlation analysis, and Cox regression for survival analysis. P<0.05 was considered statistically significant. Results: Among the 150 patients, there were 38 RCB-0, 12 RCB-Ⅰ, 61 RCB-Ⅱ and 39 RCB-Ⅲ post NAC. RCB-0 meant pathological complete response (PCR). Statistical analysis found that the pre NAC HER2 expression was related to PCR and RCB classification after surgery (r1=‒0.217,r2=‒0.282;P<0.05). Further analysis demonstrated that in the HER2-positive group, PCR was associated with prolonged OS and DFS (HR=2.939, 2.359; P<0.05); the differences of OS and DFS in RCB classifications were more significant (P<0.05) in the HER2 positive than HER2 negative groups. Conclusion: There is a correlation between pre NAC HER2 expression and PCR and RCB classification after treatment. In HER2-positive patients, the prognostic stratification of RCB classification is more obvious, suggesting that pre NAC HER2 overexpression combined with RCB classification after surgery can more accurately predict the prognosis.