Favorable Pathologic Response Research Articles

Factors associated with favourable pathological tumour response after neoadjuvant chemotherapy in patients with pancreatic ductal adenocarcinoma

IntroductionPathological response of pancreatic ductal adenocarcinoma (PDAC) to neoadjuvant chemotherapy (NAT) has been associated with oncological outcome. The aim of the study was to investigate factors associated with favourable tumour regression in patients undergoing pancreatic resection for PDAC. MethodsPatients who received NAT before undergoing PDAC resection at two institutions were reviewed. Tumour regression grading (TRG) was scored according to the College of American Pathologists (CAP) system. Interactions between chemotherapy, tumour and surgical factors with TRG were explored. Results54 patients were identified, with 12 (22%) displaying a favourable response to NAT. The type of chemotherapy agent received, the number of cycles or a dose reduction during NAT course was not significantly different between the groups. The time from diagnosis to chemotherapy and time from end of chemotherapy to surgery were also similar between the groups. A favourable TRG was associated with greater disease-free survival median 33.2 months vs. 10.3 months; p = 0.0) but not overall survival (median 43.8 months vs. 32.3 months; p = 0.200), which may be due to small sample size. ConclusionsChemotherapy factors were not significantly related to a favourable response to NAT. Future studies should seek to identify modifiable factors associated with a favourable TRG.

Circulating Lipid Profiles Associated With Resistance to Androgen Deprivation Therapy in Localized Prostate Cancer.

Intense androgen deprivation therapy (ADT) with androgen receptor pathway inhibitors (ARPIs) before radical prostatectomy (RP) produced favorable pathologic responses in approximately 20% of patients. The molecular reason for the low rate of response remains unclear. Lipid metabolism is known to influence androgen receptor signaling and ARPI efficacy. The aim of the study was to identify circulating lipid profiles associated with ADT/ARPI resistance in localized prostate cancer. Two independent experimental approaches were used. Experiment 1: Post hoc analysis of the association between plasma lipidomic profiles and ADT/ARPI response was performed on patients (n = 104) from two phase II trials of neoadjuvant ADT/ARPI. Response to ADT/ARPI was defined by pathologic response. Experiment 2: Patient-derived tumor explants from RP (n = 105) were cultured in enzalutamide for 48 hours. Explant response to enzalutamide was evaluated against pre-RP plasma lipidomic profiles (n = 105) and prostate tissue lipidomic profiles (n = 36). Response was defined by Ki67 (cell proliferation marker) fold difference between enzalutamide and vehicle-treated explants. In both experiments, associations between lipid profiles and ADT/ARPI response were analyzed by latent class analysis. Pretreatment plasma lipid profiles classified each experimental cohort into two groups with differences in ADT/ARPI response rates. The response rates of the groups were 9.6% versus 29% in experiment 1 (chi-squared test P = .012) and 49% versus 70% in experiment 2 (chi-squared test P = .037). In both experiments, the group with a higher incidence of ADT/ARPI resistance had higher plasma levels of sphingomyelin, glycosylceramides, free fatty acids, acylcarnitines, cholesterol esters, and alkyl/alkenyl-phosphatidylcholine and lower plasma levels of triacylglycerols, diacylglycerols, and phosphoethanolamine (t-test P < .05). Pretreatment circulating lipid profiles are associated with ADT/ARPI resistance in localized cancer in both human cohorts and explant models.

Final analysis of a phase II trial of neoadjuvant chemoimmunotherapy for locoregionally advanced head and neck squamous cell carcinoma

ObjectivesNeoadjuvant chemoimmunotherapy has shown promising results for resectable, locoregionally advanced (LA) head and neck squamous cell carcinoma (L/A HNSCC). We published the first phase II trial of neoadjuvant camrelizumab combined with chemotherapy in resectable, L/A HNSCC, demonstrating it was safe and feasible with favorable pathological complete response (pCR). Here, we report the final analysis results for neoadjuvant chemoimmunotherapy in L/A HNSCC (minimum 2.0 years of follow-up). Materials and methodsThree cycles of chemoimmunotherapy were administered before surgery to patients with L/A HNSCC. Two-year disease-free survival (DFS), overall survival (OS) and quality of life (QOL) were reported. ResultsThe overall two-year DFS and OS rates were 90 % and 100 %, respectively. With a median follow-up of 33.7 months, 9 of 10 (90 %) patients with pCR were alive and disease free. Patients with TNM stage (II/III) or < 20 % of residual viable tumor trended toward improved DFS; hazard ratio (HR), 0.44 [95 % confidence interval (CI), 0.04–5.28] and HR, 0.26 (95 % CI, 0.03–2.36), respectively. All QLQ-C30 functioning and symptom scales other than nausea and vomiting were resolved at 2 years after the completion of radiotherapy. ConclusionNeoadjuvant camrelizumab in combination with chemotherapy provided encouraging clinical outcomes for patients with L/A HNSCC. Further studies with longer follow-up and larger samples are warranted.Trial registration: Chictr.org.cn, ChiCTR1900025303. Registered Aug 22, 2019. https://www.chictr.org.cn/showproj.html?proj=41380.

A phase II trial of neoadjuvant nivolumab, docetaxel, and cisplatin followed by surgery and radiation therapy for resectable high-grade salivary gland carcinoma.

e18061 Background: High-grade resectable salivary gland carcinomas, typically treated with surgery and adjuvant therapies, often recur. This study explores combining an immune checkpoint inhibitor (ICI) with chemotherapy as neoadjuvant therapy to improve outcomes in high-risk, operable cases. Methods: This trial enrolled high-grade SGC patients with clinically positive lymph nodes. Participants received three cycles of nivolumab in conjunction with docetaxel and cisplatin every three weeks. The primary response was assessed three weeks post-treatment, and surgery followed at seven weeks in cases deemed operable. The pathologic outcomes determined the need for adjuvant radiotherapy, administered at 59.4Gy (R0) or 66.0Gy (R1 or R2). The study's primary endpoint was the major pathologic response rate (MPR). We aimed to recruit 50 patients. Herein, we present an interim analysis (NCT05727410). Results: Since November 2022, 19 patients have enrolled; predominantly male (89.5%) with a median age of 62 (range 42-75). Histologic analysis identified various subtypes, primarily salivary duct carcinoma (68.4%). Other histologies included high-grade adenocarcinoma (10.5%), mucoepidermoid carcinoma (10.5%), basaloid squamous cell carcinoma (5.3%), and secretary carcinoma (5.3%). At the time point of analysis, surgery was performed on 16 patients, and 3 patients are still under neoadjuvant therapy. Complete resection (R0) was achieved in 87.5% (n=14) of the cases, with one patient having R1 and another R2 resection. Pathologic analysis showed 12.5% (n=2) achieving pathological complete response and 18.8% (n=3) achieving MPR. Tumor viability varied, with 37.5% (n=6) presenting with 10% to 50% viability and 31.3% (n=5) presenting with 50% or higher viability. A patient with salivary duct carcinoma histology with tumor viability of 20% after neoadjuvant treatment experienced recurrence after 4.1 months from surgery. Notably, throughout the neoadjuvant treatment phase, no patients discontinued due to toxicity or intolerance, indicating a favorable tolerance profile for the combination therapy. An ongoing exploratory biomarker study includes PD-L1 expression and genomic profiling. Conclusions: The preliminary findings of this study demonstrate that the neoadjuvant combination of immune checkpoint inhibitor with chemotherapy significantly reduces tumor burden in salivary gland carcinoma, as evidenced by the high rate of complete resections (R0) and favorable pathologic responses. This treatment strategy not only facilitates surgical outcomes but also exhibits an acceptable safety profile, with no instances of treatment discontinuation due to toxicity or intolerance. These promising results underscore the potential of ICI combination therapy in the management of SGC and warrant further detailed investigations. Clinical trial information: NCT05727410 .

Comparison of neoadjuvant chemotherapy or chemoradiotherapy plus immunotherapy for locally resectable esophageal squamous cell carcinoma.

Neoadjuvant chemotherapy plus immunotherapy (nCT + ICIs) and neoadjuvant chemoradiotherapy plus immunotherapy (nCRT + ICIs) both induced favorable pathological response and tolerant toxicities for locally resectable esophageal squamous cell carcinoma (ESCC). However, few studies compared safety and efficacy between the two treatment strategies. This retrospective study collected clinical data of locally resectable ESCC patients who underwent nCT + ICIs or nCRT + ICIs followed by esophagectomy from November 2019 to December 2022. The incidence of adverse events, surgical outcomes, short and long-term efficacy, and treatment costs were compared. A total of 206 patients were included, with a ratio of 158:48 between nCT + ICIs group and nCRT + ICIs group. The two groups exhibited well-balanced baseline characteristics. Most adverse events were grade 1-2 in both groups. The nCT + ICIs group had a longer operative time (334.00 ± 170.2min vs 279.60 ± 88.31min, P=0.020) than nCRT + ICIs group, but there were no differences in surgical complications. Although nCT + ICIs group had a lower pCR rate (32.3% vs 52.1%, P=0.004), the 2-year overall survival (84.42% vs 81.70%, P=0.860), 2-year disease-free survival (83.21% vs 80.47%, P=0.839), and recurrence patterns were similar to nCRT + ICIs group. In addition, nCT + ICIs group had significantly lower expenses (188796.00 ± 107704.00 RMB vs 231808.00 ± 48067.00 RMB, P=0.045). Overall, nCT + ICIs have comparable safety and efficacy compared to nCRT + ICIs for locally resectable ESCC, but with lower hospitalization costs.

Habitat escalated adaptive therapy (HEAT): a phase 2 trial utilizing radiomic habitat-directed and genomic-adjusted radiation dose (GARD) optimization for high-grade soft tissue sarcoma

BackgroundSoft tissue sarcomas (STS), have significant inter- and intra-tumoral heterogeneity, with poor response to standard neoadjuvant radiotherapy (RT). Achieving a favorable pathologic response (FPR ≥ 95%) from RT is associated with improved patient outcome. Genomic adjusted radiation dose (GARD), a radiation-specific metric that quantifies the expected RT treatment effect as a function of tumor dose and genomics, proposed that STS is significantly underdosed. STS have significant radiomic heterogeneity, where radiomic habitats can delineate regions of intra-tumoral hypoxia and radioresistance. We designed a novel clinical trial, Habitat Escalated Adaptive Therapy (HEAT), utilizing radiomic habitats to identify areas of radioresistance within the tumor and targeting them with GARD-optimized doses, to improve FPR in high-grade STS.MethodsPhase 2 non-randomized single-arm clinical trial includes non-metastatic, resectable high-grade STS patients. Pre-treatment multiparametric MRIs (mpMRI) delineate three distinct intra-tumoral habitats based on apparent diffusion coefficient (ADC) and dynamic contrast enhanced (DCE) sequences. GARD estimates that simultaneous integrated boost (SIB) doses of 70 and 60 Gy in 25 fractions to the highest and intermediate radioresistant habitats, while the remaining volume receives standard 50 Gy, would lead to a > 3 fold FPR increase to 24%. Pre-treatment CT guided biopsies of each habitat along with clip placement will be performed for pathologic evaluation, future genomic studies, and response assessment. An mpMRI taken between weeks two and three of treatment will be used for biological plan adaptation to account for tumor response, in addition to an mpMRI after the completion of radiotherapy in addition to pathologic response, toxicity, radiomic response, disease control, and survival will be evaluated as secondary endpoints. Furthermore, liquid biopsy will be performed with mpMRI for future ancillary studies.DiscussionThis is the first clinical trial to test a novel genomic-based RT dose optimization (GARD) and to utilize radiomic habitats to identify and target radioresistance regions, as a strategy to improve the outcome of RT-treated STS patients. Its success could usher in a new phase in radiation oncology, integrating genomic and radiomic insights into clinical practice and trial designs, and may reveal new radiomic and genomic biomarkers, refining personalized treatment strategies for STS.Trial registrationNCT05301283.Trial statusThe trial started recruitment on March 17, 2022.

Single-cell profiling of response to neoadjuvant chemo-immunotherapy in surgically resectable esophageal squamous cell carcinoma

BackgroundThe efficacy of neoadjuvant chemo-immunotherapy (NAT) in esophageal squamous cell carcinoma (ESCC) is challenged by the intricate interplay within the tumor microenvironment (TME). Unveiling the immune landscape of ESCC in the context of NAT could shed light on heterogeneity and optimize therapeutic strategies for patients.MethodsWe analyzed single cells from 22 baseline and 24 post-NAT treatment samples of stage II/III ESCC patients to explore the association between the immune landscape and pathological response to neoadjuvant anti-PD-1 combination therapy, including pathological complete response (pCR), major pathological response (MPR), and incomplete pathological response (IPR).ResultsSingle-cell profiling identified 14 major cell subsets of cancer, immune, and stromal cells. Trajectory analysis unveiled an interesting link between cancer cell differentiation and pathological response to NAT. ESCC tumors enriched with less differentiated cancer cells exhibited a potentially favorable pathological response to NAT, while tumors enriched with clusters of more differentiated cancer cells may resist treatment. Deconvolution of transcriptomes in pre-treatment tumors identified gene signatures in response to NAT contributed by specific immune cell populations. Upregulated genes associated with better pathological responses in CD8 + effector T cells primarily involved interferon-gamma (IFNγ) signaling, neutrophil degranulation, and negative regulation of the T cell apoptotic process, whereas downregulated genes were dominated by those in the immune response-activating cell surface receptor signaling pathway. Natural killer cells in pre-treatment tumors from pCR patients showed a similar upregulation of gene expression in response to IFNγ but a downregulation of genes in the neutrophil-mediated immunity pathways. A decreased cellular contexture of regulatory T cells in ESCC TME indicated a potentially favorable pathological response to NAT. Cell–cell communication analysis revealed extensive interactions between CCL5 and its receptor CCR5 in various immune cells of baseline pCR tumors. Immune checkpoint interaction pairs, including CTLA4-CD86, TIGIT-PVR, LGALS9-HAVCR2, and TNFSF4-TNFRSF4, might serve as additional therapeutic targets for ICI therapy in ESCC.ConclusionsThis pioneering study unveiled an intriguing association between cancer cell differentiation and pathological response in esophageal cancer patients, revealing distinct subgroups of tumors for which neoadjuvant chemo-immunotherapy might be effective. We also delineated the immune landscape of ESCC tumors in the context of clinical response to NAT, which provides clinical insights for better understanding how patients respond to the treatment and further identifying novel therapeutic targets for ESCC patients in the future.

Effectiveness and safety of neoadjuvant apatinib in combination with capecitabine and oxaliplatin for the therapy of locally advanced colorectal cancer: A retrospective study.

The goal of the present study was to appraise the efficacy and safety of neoadjuvant apatinib in combination with capecitabine and oxaliplatin (XELOX) in patients with locally advanced colorectal cancer (CRC), as relevant data on its usage in this setting are lacking. A retrospective analysis was implemented on 100 patients with locally advanced CRC who received either neoadjuvant apatinib in combination with XELOX (N=50) or neoadjuvant XELOX alone (N=50). Radiological response and pathological complete response rates were evaluated. Furthermore, the researchers obtained data pertaining to disease-free survival (DFS), overall survival, as well as adverse events. The consequences of the present study indicated that the neoadjuvant apatinib in combination with XELOX treatment approach yielded higher rates of radiological objective response (86.0 vs. 68.0%, P=0.032) and major pathological response (46.0 vs. 22.0%, P=0.011) compared with XELOX alone. These findings were further confirmed through multivariate logistic regression analyses (P=0.037 and P=0.008, respectively). Interestingly, the neoadjuvant apatinib in combination with XELOX treatment approach significantly prolonged DFS when compared with XELOX alone (P=0.033). In summary, the administration of neoadjuvant apatinib in combination with XELOX demonstrates superiority over the use of XELOX alone in terms of achieving a more favorable pathological response and a longer duration of DFS in patients diagnosed with locally advanced CRC.

The presence of intraductal carcinoma of prostate is a risk factor for poor pathologic response in men with high-risk prostate cancer receiving neoadjuvant therapy

ObjectiveTo explore the potential association between the presence of intraductal carcinoma of the prostate (IDC-P) on biopsy and pathologic response of primary tumor to neoadjuvant therapy in patients with high-risk prostate cancer. MethodsEighty-five patients with high-risk localized/locally advanced prostate cancer (CaP) who were given 6-month neoadjuvant therapies of androgen deprivation therapy plus docetaxel or abiraterone prior to radical prostatectomy in 2 prospective trials were included in this study. The presence of IDC-P in biopsy pathology was rereviewed by 2 experienced pathologists. Favorable pathologic response was defined as pathologic complete response or minimal residual disease <5 mm on whole-mount histopathology. Characteristics of clinical and biopsy pathology variables were included in univariate and multivariate logistic regression analyses to identify risk factors for the prediction of favorable pathologic response on final pathology. ResultsIDC-P was identified to be present on biopsy pathology of 35 patients (41.2%) while favorable pathologic responses were confirmed in 25 patients (29.4%). Initial prostate-specific antigen (PSA) (OR 3.592, 95% CI 1.176–10.971, P = 0.025) and the presence of IDC-P on biopsy pathology (OR 3.837, 95% CI 1.234–11.930, P = 0.020) were found to be significantly associated with favorable pathologic response in multivariate logistic regression analysis. ConclusionIDC-P on biopsy pathology was found to be an independent risk factor to predict a poor pathology response of primary CaP to neoadjuvant therapies.

Characterization of BCL-X L , MCL-1, and BAX Protein Expression in Response to Neoadjuvant Chemotherapy in Breast Cancer.

The use of chemotherapy has improved the overall treatment of breast cancer, which is frequently administered in the form of neoadjuvant chemotherapy (NAC). Apoptosis is an established cell stress response to NAC in preclinical models; however, there is limited understanding of its role in clinical cancer, specifically, its contribution to favorable pathologic responses in breast cancer therapy. Here, we aimed to characterize the change in protein expression of 3 apoptosis-associated biomarkers, namely, BCL-X L , MCL-1, and BAX in breast cancer in response to NAC. For this, we utilized a set of 68 matched invasive breast cancer FFPE samples that were collected before (pre) and after (post) the exposure to NAC therapy that were characterized by incomplete pathologic response. Immunohistochemistry (IHC) analysis suggested that most of the samples show a decrease in the protein expression of all 3 markers following exposure to NAC as 90%, 69%, and 76% of the matched samples exhibited a decrease in expression for BCL-X L , MCL-1, and BAX, respectively. The median H-score of BCL-X L post-NAC was 150/300 compared with 225/300 pre-NAC ( P value <0.0001). The median H-score of MCL-1 declined from 200 pre-NAC to 160 post-NAC ( P value <0.0001). The median H-score of BAX protein expression decreased from 260 pre-NAC to 190 post-NAC ( P value <0.0001). There was no statistically significant association between the expression of these markers and stage, grade, and hormone receptor profiling (luminal status). Collectively, our data indicate that the expression of apoptosis regulatory proteins changes following exposure to NAC in breast cancer tissue, developing a partial pathologic response.

Neoadjuvant cobimetinib and atezolizumab with or without vemurafenib for high-risk operable Stage III melanoma: the Phase II NeoACTIVATE trial

Both targeted therapies and immunotherapies provide benefit in resected Stage III melanoma. We hypothesized that the combination of targeted and immunotherapy given prior to therapeutic lymph node dissection (TLND) would be tolerable and drive robust pathologic responses. In NeoACTIVATE (NCT03554083), a Phase II trial, patients with clinically evident resectable Stage III melanoma received either 12 weeks of neoadjuvant vemurafenib, cobimetinib, and atezolizumab (BRAF-mutated, Cohort A, n = 15), or cobimetinib and atezolizumab (BRAF-wild-type, Cohort B, n = 15) followed by TLND and 24 weeks of adjuvant atezolizumab. Here, we report outcomes from the neoadjuvant portion of the trial. Based on intent to treat analysis, pathologic response (≤50% viable tumor) and major pathologic response (complete or near-complete, ≤10% viable tumor) were observed in 86.7% and 66.7% of BRAF-mutated and 53.3% and 33.3% of BRAF-wild-type patients, respectively (primary outcome); these exceeded pre-specified benchmarks of 50% and 30% for major pathologic response. Grade 3 and higher toxicities, primarily dermatologic, occurred in 63% during neoadjuvant treatment (secondary outcome). No surgical delays nor progression to regional unresectability occurred (secondary outcome). Peripheral blood CD8 + TCM cell expansion associated with favorable pathologic responses (exploratory outcome).

Recurrence-free survival as a surrogate endpoint for overall survival after neoadjuvant chemotherapy and surgery for oesophageal squamous cell carcinoma.

Overall survival is considered as one of the most important endpoints of treatment efficacy but often requires long follow-up. This study aimed to determine the validity of recurrence-free survival as a surrogate endpoint for overall survival in patients with surgically resectable advanced oesophageal squamous cell carcinoma (OSCC). Patients with OSCC who received neoadjuvant cisplatin and 5-fluorouracil, or docetaxel, cisplatin and 5-fluorouracil, at 58 Japanese oesophageal centres certified by the Japan Esophageal Society were reviewed retrospectively. The correlation between recurrence-free and overall survival was assessed using Kendall's τ. The study included 3154 patients. The 5-year overall and recurrence-free survival rates were 56.6 and 47.7% respectively. The primary analysis revealed a strong correlation between recurrence-free and overall survival (Kendall's τ 0.797, 95% c.i. 0.782 to 0.812) at the individual level. Subgroup analysis showed a positive relationship between a more favourable pathological response to neoadjuvant chemotherapy and a higher τ value. In the meta-regression model, the adjusted R2 value at the institutional level was 100 (95% c.i. 40.2 to 100)%. The surrogate threshold effect was 0.703. There was a strong correlation between recurrence-free and overall survival in patients with surgically resectable OSCC who underwent neoadjuvant chemotherapy, and this was more pronounced in patients with a better response to neoadjuvant chemotherapy.

The Magee 3 Equation Predicts Favorable Pathologic Response to Neoadjuvant Endocrine Therapy in Breast Cancer Patients.

Breast cancer (BC) remains a significant health care challenge, and treatment approaches continue to evolve. Among these, neoadjuvant endocrine therapy (NET) has gained prominence, particularly for postmenopausal, hormone-receptor positive, HER2-negative (HR+/HER2-) BC patients. Despite this, a significant gap exists in identifying patients who stand to benefit from NET. The objective of this study was to assess whether Magee equations (MEs) could serve as predictors of response to NET. This retrospective study included adult patients with invasive BC who underwent NET followed by curative surgery. Assessment of sociodemographic, clinical, and tumor-related variables was conducted. The ME1, ME2, ME3, and ME mean were analyzed to explore their predictive role for NET response. Receiver operating characteristic (ROC) curves were employed, along with the determination of optimal cutoff points. Logistic regression models were utilized to identify the most significant predictors of pathological response. Among the 75 female participants, the mean age was 69.4 years, with the majority being postmenopausal (n = 72, 96%) and having an ECOG-PS of 0/1 (n = 63, 84%). Most patients were classified as luminal A (n = 41, 54.7%). ME3 emerged as a promising predictor, boasting an AUC of 0.734, with sensitivity of 90.62% and specificity of 57.50% when the threshold was ≤ 19.97. In univariate analysis, clinical staging (p = 0.002), molecular subtype (p = 0.001), and ME3 (continuous = 0.001, original 3-tier: p = 0.013, new 2-tier: <0.001) categories exhibited significant associations with pathological response. In the multivariate model, clinical staging and new 2-tier ME3 (<20 vs. ≥20) were included as significant variables. Patients with ME3 < 20 have a higher likelihood of presenting a pathological response, offering a cost-effective alternative tool to Oncotype DX. Larger future studies with a prospective design are awaited to confirm our findings.

Short-term outcomes of preoperative chemotherapy with docetaxel, oxaliplatin, and S-1 for gastric cancer with extensive lymph node metastasis (JCOG1704)

BackgroundThe prognosis for marginally resectable gastric cancer with extensive lymph node metastasis (ELM) remains unfavorable, even after R0 resection. To assess the safety and efficacy of preoperative docetaxel, oxaliplatin, and S-1 (DOS), we conducted a multicenter phase II trial.MethodsEligibility criteria included histologically proven HER2-negative gastric adenocarcinoma with bulky nodal (bulky N) involvement around major branched arteries or para-aortic node (PAN) metastases. Patients received three cycles of docetaxel (40 mg/m2, day 1), oxaliplatin (100 mg/m2, day 1), and S-1 (80–120 mg/body, days 1–14), followed by gastrectomy with D2 plus PAN dissection. Subsequently, patients underwent postoperative chemotherapy with S-1 for 1 year. The primary endpoint was major (grade ≥ 2a) pathological response rate (pRR) according to the Japanese Classification of Gastric Carcinoma criteria.ResultsBetween October 2018 and March 2022, 47 patients (bulky N, 20; PAN, 17; both, 10) were enrolled in the trial. One patient was ineligible. Another declined any protocol treatments before initiation. Among the 45 eligible patients who initiated DOS chemotherapy, 44 (98%) completed 3 cycles and 42 (93%) underwent R0 resection. Major pRR and pathological complete response rates among the 46 eligible patients, including the patient who declined treatment, were 57% (26/46) and 24% (11/46), respectively. Common grade 3 or 4 toxicities were neutropenia (24%), anorexia (16%), febrile neutropenia (9%), and diarrhea (9%). No treatment-related deaths occurred.ConclusionsPreoperative chemotherapy with DOS yielded favorable pathological responses with an acceptable toxicity profile. This multimodal approach is highly promising for treating gastric cancer with ELM.

HPB P12 Do Chemotherapy Factors or Treatment Intervals Influence Pathological Tumour Response during Neoadjuvant Chemotherapy for Pancreatic Ductal Adenocarcinoma? A Bi-Institutional Study

Abstract Background Pathological response of pancreatic ductal adenocarcinoma (PDAC) to neoadjuvant chemotherapy (NAT) can be assessed using grading systems such as the College of American Pathologists (CAP) system, with favourable regression being associated with improved oncological outcomes. The aim of the study was to investigate factors associated with favourable tumour regression in patients undergoing pancreatoduodenectomy (PD) for PDAC. Methods Patients who received NAT before undergoing PDAC resection at two institutions in the United Kingdom between 2013 and 2021 were reviewed. Interactions between chemotherapy regimens, tumour staging, carbohydrate antigen 19-9 (Ca19-9) levels, perioperative factors and tumour regression grading (TRG) were explored. Results 54 patients were identified who were suitable for inclusion. 12 (22%) patients had a favourable response to NAT according to the CAP grading system. A significantly greater reduction in Ca19-9 observed in the favourable TRG group [mean -2359 U/mL] compared to the unfavourable TRG group [mean -569 U/mL (p&amp;lt;0.001). The type of chemotherapy agent received, the number of cycles or whether the patient had a dose reduction during their NAT course did not differ significantly between the groups. The time from diagnosis to chemotherapy and time from end of chemotherapy to surgery were also similar between the groups. Conclusions In this bi-institutional retrospective study, neither chemotherapy factors nor treatment intervals were not found to be significantly related to pathological tumour response to NAT in PDAC patients undergoing resection. Given that a favourable pathological response has been related to improved oncological outcomes, future research should concentrate on further mechanisms that may influence the response of PDAC tumours to NAT, such as gene expression and the tumour microbiome. Given that NAT is also a relatively new approach, further multicentre collaboration should be encouraged to increase numbers of patients for study.

Pathologic tumor response to neoadjuvant therapy in resected pancreatic cancer: does it affect prognosis?

Neoadjuvant therapy (NAT) + surgical resection for pancreatic cancer (PC) has gained consensus in recent years. Pathological response (PR) is generally assessed according to the College of American Pathologists grading system, ranging from 0 (complete response) to 3 (no response). The aim of our study is to evaluate the PR in a series of resections for PC after NAT and its prognostic implication. 112 patients undergone NAT and resection for PC between 2011 and 2020 were retrospectively evaluated. PR was 0/1, 2 and 3 in 18 (15%), 79 (61%) and 29 (24%) cases, respectively. Chemotherapy regimens different from FOLFIRINOX and gemcitabine + nab-paclitaxel (OR 11.61 (2.53-53.36), p = 0.002) and lymphovascular invasion (OR 11.28 (1.89-67.23), p = 0.008) were associated to PR-3. Median follow-up was 25.8 (3.6-130.5) months. For PR-0/1, PR-2 and PR-3, median DFS was 45.8, 11.5, 4.6months (p < 0.0001), respectively, while median OS was not reached, 27.1 and 17.5months (p = 0.0006), respectively. At univariate analysis, PR-0/1 was significantly associated to better DFS and OS (HR 0.33 (0.17-0.67), p = 0.002; HR 0.20 (0.07-0.54), p = 0.002, respectively). At multivariate analysis, pancreaticoduodenectomy (HR 0.50 (0.30-0.84), p = 0.009), LNR (HR 27.14 (1.21-608.9), p = 0.038) and lymphovascular invasion (HR 1.99 (1.06-3.76), p = 0.033) were independently associated to DFS; pre-treatment CA 19.9 value (HR 1.00 (1.00-1.00), p = 0.025), post-treatment resectability status (HR 0.51 (0.28-0.95), p = 0.035), pancreaticoduodenectomy (HR 0.56 (0.32-0.99), p = 0.050), severe morbidity (2.99 (1.22-7.55), p = 0.017), LNR (HR 56.8 (2.08-1548.3), p = 0.017), lymphovascular invasion (HR 2.18 (1.08-4.37), p = 0.029) were independently associated to OS. PR did not reach statistical significance at multivariate analysis. A favorable PR is observed only in a limited number of cases. The prognostic role of PR, despite being promising, remains unclear and further multicentric studies are needed.

Predictive factors associated with differential pathologic response to neoadjuvant chemohormonal therapy in high-risk localized prostate cancer

To explore the clinical parameters and molecular biomarkers that can predict differential pathologic response to neoadjuvant chemohormonal therapy (NCHT) in prostate cancer (CaP).A total of 128 patients with primary high-risk localized CaP who had received NCHT followed by radical prostatectomy (RP) were included. Androgen receptor (AR), AR splice variant-7 (AR-V7) and Ki-67 staining were evaluated in prostate biopsy specimens by immunohistochemistry. The pathologic response to NCHT in whole mount RP specimens was measured based on the reduction degree of tumor volume and cellularity compared to the paired pretreatment needle biopsy, and divided into 5 tier grades (Grades 0-4). Patients with Grades 2 to 4 (the reduction degree more than 30%) were defined as having a favorable response. Logistic regression was performed to explore the predictive factors associated with a favorable pathologic response. The predictive accuracy was evaluated by receiver operating characteristic (ROC) curve and area under the ROC curve (AUC).Ninety-seven patients (75.78%) had a favorable response to NCHT. Logistic regression showed that the preoperative PSA level, low AR expression and high Ki-67 expression in biopsy specimens were associated with a favorable pathologic response (P < 0.05). Furthermore, the AUC of the preoperative PSA level, AR and Ki-67 were 0.625, 0.624 and 0.723, respectively. Subgroup analysis revealed that the rate of favorable pathologic response to NCHT was 88.5% in patients with ARlowKi-67high, which was higher than patients with ARlowKi-67low, ARhighKi-67low, and ARhighKi-67high (88.5% vs. 73.9%, 72.9%, and 70.9%, all P < 0.05).A lower preoperative PSA level was an independent predictive factor for a favorable pathologic response. Moreover, the expression status of AR and Ki-67 in biopsy specimens were associated with differential pathologic response to NCHT, and AR low/Ki-67 high was also associated with favorable response but warrants further evaluation in this patient subgroup and future trial clinical trial design.

The Association Between [68Ga]PSMA PET/CT Response and Biochemical Progression in Patients with High-Risk Prostate Cancer Receiving Neoadjuvant Therapy.

Our previous study found that the prostate-specific membrane antigen (PSMA) PET/CT response of primary prostate cancer (PCa) to neoadjuvant therapy can predict the pathologic response. This study was designed to investigate the association between [68Ga]PSMA PET/CT changes and biochemical progression-free survival (bPFS) in high-risk patients who underwent neoadjuvant therapy before radical prostatectomy (RP). Methods: Seventy-five patients with high-risk PCa in 2 phase II clinical trials who received neoadjuvant therapy before RP were included. The patients received androgen deprivation therapy plus docetaxel (n = 33) or androgen deprivation therapy plus abiraterone (n = 42) as neoadjuvant treatment. All patients had serial [68Ga]PSMA PET/CT scans before and after neoadjuvant therapy. Age, initial prostate-specific antigen level, nadir prostate-specific antigen level before RP, tumor grade at biopsy, treatment regimen, clinical T stage, PET imaging features, pathologic N stage, and pathologic response on final pathology were included for univariate and multivariate Cox regression analyses to identify independent predictors of bPFS. Results: With a median follow-up of 30 mo, 18 patients (24%) experienced biochemical progression. Multivariate Cox regression analyses revealed that only SUVmax derived from posttreatment [68Ga]PSMA PET/CT and pathologic response on final pathology were independent factors for the prediction of bPFS, with hazard ratios of 1.02 (95% CI, 1.00-1.04; P = 0.02) and 0.12 (95% CI, 0.02-0.98; P = 0.048), respectively. Kaplan-Meier analysis revealed that patients with a favorable [68Ga]PSMA PET/CT response (posttreatment SUVmax < 8.5) or a favorable pathologic response (pathologic complete response or minimal residual disease) had a significantly lower rate of 3-y biochemical progression. Conclusion: Our results indicated that [68Ga]PSMA PET/CT response was an independent risk factor for the prediction of bPFS in patients with high-risk PCa receiving neoadjuvant therapy and RP, suggesting [68Ga]PSMA PET/CT to be an ideal tool to monitor response to neoadjuvant therapy.

Clinical and morphological response to neoadjuvant chemotherapy followed by chemoradiotherapy in a patient with locally advanced gastric cancer: a case report

Background. Gastric cancer is one of the most common cancers with the highest incidence and mortality rates worldwide. Gastrectomy/distal subtotal resection with D2 lymphadenectomy and perioperative chemotherapy with FLOT is the standard treatment for locally advanced gastric cancer. Currently, the role of chemoradiation therapy in the treatment of gastric cancer has not been well determined. From 2019 to 2021, a prospective phase 2 clinical trial was undertaken at A. Tsyb Medical Radiological Research Centre (MRRC) to evaluate the safety and efficacy of neoadjuvant therapy: induction chemotherapy with FLOT (2 cycles) and chemoradiotherapy (total dose of 46 Gy with the concurrent chemotherapy with capecitabine and oxaliplatin) followed by surgery. The aim of the study was to demonstrate the effectiveness of neoadjuvant therapy for locally advanced gastric cancer with a favorable pathological response, downstaging and more than 2.5-year disease-free survival. Case description. A 48 year-old male patient was admitted to the MRRC with complain of epigastric pains for 2 months. Gastroscopic biopsy revealed gastric cancer. The comprehensive examination revealed proximal gastric cancer involving the abdominal segment of the esophagus (cT3N3aM0, stage III). The patient was invited to participate in the clinical trial. The patient accepted to participate voluntarily and signed an informed consent. He received 2 cycles of FLOT chemotherapy followed by chemoradiotherapy and surgery (gastrectomy with resection of the abdominal segment of the esophagus and D2 lymph node dissection). Histological examination of the surgical specimen revealed grade 1b pathological response (Becker criteria). Histological examination of lymph nodes revealed pathological complete response. The patient is alive after 33 months of gollow-up without the evidence of disease progression. Conclusion. Neoadjuvant induction chemotherapy followed by chemoradiotherapy resulted in a favorable pathological response, downstaging and 2.5-year disease-free survival.

Intensive cycles of neoadjuvant camrelizumab combined with chemotherapy in locally advanced esophageal squamous cell carcinoma: a single-arm, phase II trial

BackgroundTwo cycles of neoadjuvant PD-1 blockade plus chemotherapy induced favorable pathological response and tolerant toxicity in patients with locally advanced esophageal squamous cell carcinoma (ESCC). However, approximately 25% of patients relapsed within 1 year after surgery, indicating that a short course of treatment may not be sufficient. Therefore, exploring the effects of intensive treatment is needed for optimal clinical outcomes.MethodsLocally advanced ESCC patients were administered three cycles of camrelizumab plus nab-paclitaxel and capecitabine, followed by thoracoscopic esophagectomy. The primary endpoint was pathologic response. Secondary endpoints included safety, feasibility, radiologic response, survival outcomes, and immunologic/genomic correlates of efficacy.ResultsForty-seven patients were enrolled in the study. Forty-two patients received surgery, and R0 resection was achieved in all cases. The complete and major pathological response rates were 33.3% and 64.3%, respectively, and the objective response rate was 80.0%. Three cycles of treatment significantly improved T down-staging compared to two cycles (P = 0.03). The most common treatment-related adverse events were grades 1–2, and no surgical delay was reported. With a median follow-up of 24.3 months, the 1-year disease-free survival and overall survival rates were both 97.6%, and the 2-year disease-free survival and overall survival rates were 92.3% and 97.6%, respectively. Three patients experienced disease recurrence or metastasis ranging from 12.5 to 25.8 months after surgery, and one patient died 6 months after surgery due to cardiovascular disease. Neither programmed death-ligand 1 expression nor tumor mutational burden was associated with pathological response. An increased infiltration of CD56dim natural killer cells in the pretreatment tumor was correlated with better pathological response in the primary tumor.ConclusionsIt seems probable that intensive cycles of neoadjuvant camrelizumab plus nab-paclitaxel and capecitabine increased tumor regression and improved survival outcomes. Randomized controlled trials with larger sample sizes and longer follow-up periods are needed to validate these findings.Trial registration Chinese Clinical Trial Registry, ChiCTR2000029807, Registered February 14, 2020, https://www.chictr.org.cn/showproj.aspx?proj=49459.