A machine learning radiomics based on enhanced computed tomography to predict neoadjuvant immunotherapy for resectable esophageal squamous cell carcinoma.

Background: Patients with resectable esophageal squamous cell carcinoma (ESCC) receiving neoadjuvant immunotherapy (NIT) display variable treatment responses. The purpose of this study is to establish and validate a radiomics based on enhanced computed tomography (CT) and combined with clinical data to predict the major pathological response to NIT in ESCC patients. Methods: This retrospective study included 82 ESCC patients who were randomly divided into the training group (n = 57) and the validation group (n = 25). Radiomic features were derived from the tumor region in enhanced CT images obtained before treatment. After feature reduction and screening, radiomics was established. Logistic regression analysis was conducted to select clinical variables. The predictive model integrating radiomics and clinical data was constructed and presented as a nomogram. Area under curve (AUC) was applied to evaluate the predictive ability of the models, and decision curve analysis (DCA) and calibration curves were performed to test the application of the models. Results: One clinical data (radiotherapy) and 10 radiomic features were identified and applied for the predictive model. The radiomics integrated with clinical data could achieve excellent predictive performance, with AUC values of 0.93 (95% CI 0.87-0.99) and 0.85 (95% CI 0.69-1.00) in the training group and the validation group, respectively. DCA and calibration curves demonstrated a good clinical feasibility and utility of this model. Conclusion: Enhanced CT image-based radiomics could predict the response of ESCC patients to NIT with high accuracy and robustness. The developed predictive model offers a valuable tool for assessing treatment efficacy prior to initiating therapy, thus providing individualized treatment regimens for patients.

Respective contribution of baseline clinical data, tumour metabolism and tumour blood-flow in predicting pCR after neoadjuvant chemotherapy in HER2 and Triple Negative breast cancer.

BACKGROUND: The aim of this study is to investigate the added value of combining tumour blood flow (BF) and metabolism parameters, including texture features, with clinical parameters to predict, at baseline, the pathological complete response (pCR) to neoadjuvant chemotherapy (NAC) in patients with newly diagnosed breast cancer (BC). METHODS: One hundred and twenty-eight BC patients underwent a 18F-FDG PET/CT before any treatment. Tumour BF and metabolism parameters were extracted from first-pass dynamic and delayed PET images, respectively. Standard and texture features were extracted from BF and metabolic images. Prediction of pCR was performed using logistic regression, random forest and support vector classification algorithms. Models were built using clinical (C), clinical and metabolic (C+M) and clinical, metabolic and tumour BF (C+M+BF) information combined. Algorithms were trained on 80% of the dataset and tested on the remaining 20%. Univariate and multivariate features selections were carried out on the training dataset. A total of 50 shuffle splits were performed. The analysis was carried out on the whole dataset (HER2 and Triple Negative (TN)), and separately in HER2 (N=76) and TN (N=52) tumours. RESULTS: In the whole dataset, the highest classification performances were observed for C+M models, significantly (p-value<0.01) higher than C models and better than C+M+BF models (mean balanced accuracy of 0.66, 0.61, and 0.64 respectively). For HER2 tumours, equal performances were noted for C and C+M models, with performances higher than C+M+BF models (mean balanced accuracy of 0.64, and 0.61 respectively). Regarding TN tumours, the best classification results were reported for C+M models, with better performances than C and C+M+BF models but not significantly (mean balanced accuracy of 0.65, 0.63, and 0.62 respectively). CONCLUSION: Baseline clinical data combined with global and texture tumour metabolism parameters assessed by 18F-FDG PET/CT provide a better prediction of pCR after NAC in patients with BC compared to clinical parameters alone for TN, and HER2 and TN tumours together. In contrast, adding BF parameters to the models did not improve prediction, regardless of the tumour subgroup analysed.

Major pathological response obtained after neoadjuvant chemotherapy combined with dual immunotherapy for malignant pleural mesothelioma: a case report.

Background: Malignant pleural mesothelioma (MPM) is a rare thoracic malignancy with high morbidity and mortality. A combination of systemic therapy and surgery may be a promising modality for the treatment of MPM, but evidence-based medicine is still lacking. Case Description: Here we report a case of MPM. The patient presented to hospital with cough and sputum. After ineffective symptomatic treatment, computed tomography (CT) examination suggested a malignant tumor of pleural origin. Positron emission tomography/computed tomography (PET/CT) examination suggested no lymph node metastasis or distant metastasis. The pathologic diagnosis of MPM was confirmed after CT-guided puncture biopsy. Next, she underwent 3 courses of neoadjuvant chemotherapy combined with dual immunotherapy (carboplatin and pemetrexed combined with anti-CTLA4 and anti-PD-1), resulting in significant tumor shrinkage. After obtaining the patient's consent and completing a preoperative evaluation, we modified the extrapleural pneumonectomy (EPP) and pleurectomy/decortication (P/D) by performing a lower lobe resection and partial pleurectomy of the left lung. Intraoperative rapid frozen pathology suggested that the margins of the tumor were negative and complete resection was achieved. The postoperative pathology report showed 10% residual viable tumor, so the major pathological response (MPR) was achieved after treatment. Conclusions: MPM might respond well to neoadjuvant chemotherapy and dual immunotherapy, improving the probability of complete surgical resection and attaining an encouraging pathologic response.

Gustative Roussy Immune Score is a Predictor for Major Pathological Response in Rectal Cancer: A Result from the Preoperative Intraarterial Chemoembolization Combined with Radiotherapy (PCAR) Study.

Despite the emergence of various treatment strategies for rectal cancer based on neoadjuvant chemoradiotherapy, there is currently a lack of reliable biomarkers to determine which patients will respond well to neoadjuvant chemoradiotherapy. Through collecting hematological and biochemical parameters data of patients prior to receiving neoadjuvant chemoradiotherapy, we evaluated the predictive value of systemic inflammatory indices for pathological response and prognosis in rectal cancer patients. We found that baseline GRIm-Score was an independent predictor for MPR in rectal cancer patients. However, no association was observed between several commonly systemic inflammation indices and long-term outcome.

The Relationship Between Body Composition and Pathological Response to Neoadjuvant Chemotherapy in Breast Cancer Patients.

Background The pathological response rate in operable breast cancer (BC) patients receiving neoadjuvant chemotherapy (NAC) is postulated to be related to body composition. The success of complete pathological response (pCR) is a known prognostic factor in BC patients treated with NAC. We aimed to accurately measure body composition through BMI and skeletal muscle mass and observe their effects on pCR. Materials and methods Patients diagnosed with operable BC who had a positron emission tomography-computed tomography (PET-CT) or chest/abdominal CT taken at the time of diagnosis were retrospectively screened and enrolled in this study. Muscle mass was defined by third lumbar vertebra (L3) level transverse CT images, and data, including weight and height, were collected from the chemotherapy records. All these data were evaluated together with the postoperative pathological results. Results Sixty-nine operable BC patients with a median age of 46 (range: 29-72) years were included in the study. In all patients, regardless of sarcopenia, 23% (n = 16) achieved pCR to NAC. The pCR rate was 37.5% (n=6) in sarcopenic patients and 62.5% (n=10) in non-sarcopenic patients (p = 0.530). Overweight (n=4; 25%) and obese (n=2; 12.5%) patients also had a lower pathological response than normal-weight (n=10; 62.5%) BC patients (p=0.261). Conclusion Both sarcopenia and obesity independently and synergistically contribute to poorer pathological responses after NAC. Addressing these conditions through tailored interventions, such as nutritional support, exercise programs, and careful monitoring of body composition, could improve treatment outcomes. Further research with larger patient populations and comprehensive body measurements is essential to fully understand these relationships and develop effective strategies to mitigate their impact.

Anti-PD-(L)1-Based Neoadjuvant Therapy in Head and Neck Carcinoma: a Meta-analysis of Prospective Clinical Trials.

OBJECTIVE: This meta-analysis aims to evaluate the efficacy and safety of antiprogressive disease (PD)-(L)1-based neoadjuvant therapy in head and neck squamous cell carcinoma (HNSCC) patients and identify potential prognostic biomarkers. DATA SOURCES: Databases were systematically searched for prospective clinical trials evaluating the efficacy and safety of anti-PD-(L)1-based neoadjuvant therapy for HNSCC before January 12, 2024. REVIEW METHODS: We estimated the efficacy and safety of neoadjuvant immune checkpoint inhibitors. Subgroup and sensitivity analyses were further performed. RESULTS: A total of 570 patients from 20 studies were included. The pooled major pathological response (MPR), pathological complete response (pCR), and partial pathological response (PPR) rates were 30.7%, 15.3%, and 68.2%, respectively. Surgical complications, surgical delayed rate, all grade treatment-related adverse effects (TRAEs) and ≥Grade 3 TRAEs were 0.6%, 0.3%, 82.6%, and 9.7%, respectively. Best MPR or pCR rate was detected in patients receiving neoadjuvant anti-PD-(L)1 therapy + radiotherapy (with MPR rate of 75.5% and pCR rate of 51.1%) and neoadjuvant anti-PD-(L)1 therapy + chemotherapy groups (with MPR rate of 57.5% and pCR rate of 26.7%). No differences were detected in subgroups stratified by neoadjuvant treatment cycles, human papillomavirus (HPV) status, and tumor location. Patients with baseline Combined Positive Score (CPS) ≥ 20 have higher MPR and pCR rates compared to patients with CPS < 20. High Tumor Cell Proportion Score was also associated with MPR and pCR. Objective response rate is a strong predictor of MPR (odds ratio [OR] = 7.78, 95% confidence interval [CI] = 3.20%-18.91%) and pCR (OR = 3.24, 95% CI = 1.40%-7.48%). CONCLUSION: Anti-PD-(L)1-based neoadjuvant therapy was effective and safe for HNSCC patients.

Morphological and molecular changes of oestrogen receptor-positive breast cancer following bridging endocrine therapy: a United Kingdom multicentre study.

AIMS: Standard neoadjuvant endocrine therapy (NAET) is used for 6-9 months to downstage hormone-receptor-positive breast cancer. Bridging ET was introduced during the COVID-19 pandemic to delay surgical intervention. There are no data in the literature on the effect of short course therapy on tumour response. We aimed to analyse the effect of bridging ET and validate the previously proposed neoadjuvant ET pathological reporting criteria. METHODS AND RESULTS: This was a multicentre cohort of 256 patients who received bridging ET between March and October 2020. Assessment of paired pre- and post-NAET hormone receptors and HER2 and posttherapy Ki67 expression was done. The median duration of NAET was 45 days. In all, 86% of cases achieved partial pathological response and 9% showed minimal residual disease. Histological response to ET was observed from as early as day 6 posttherapy. Central scarring was noted in 32.8% of cases and lymphocytic infiltrate was seen in 43.4% of cases. Significant changes associated with the duration of ET were observed in tumour grade (21%), with downgrading identified in 12% of tumours (P < 0.001), progesterone receptor (PR) expression with switch to PR-negative status in 26% of cases (P < 0.001), and HER2 status with a switch from HER2-low to HER2-negative status in 32% of cases (P < 0.001). The median patient survival was 475 days, with an overall survival rate of 99.6%. CONCLUSIONS: Changes characteristic of tumour regression and significant changes in PR and HER2 occurred following a short course of NAET. The findings support biomarker testing on pretreatment core biopsies and retesting following therapy.

A combined model using pre-treatment CT radiomics and clinicopathological features of non-small cell lung cancer to predict major pathological responses after neoadjuvant chemoimmunotherapy.

OBJECTIVE: To investigate the relationship between clinical pathological characteristics, pretreatment CT radiomics, and major pathologic response (MPR) of non-small cell lung cancer (NSCLC) after neoadjuvant chemoimmunotherapy, and to establish a combined model to predict the major pathologic response of neoadjuvant chemoimmunotherapy. METHODS: A retrospective study of 211 patients with NSCLC who underwent neoadjuvant chemoimmunotherapy and surgical treatment from January 2019 to April 2021 was conducted. The patients were divided into two groups: the MPR group and the non-MPR group. Pre-treatment CT images were segmented using ITK SNAP software to extract radiomics features using Python software. Then a radiomics model, a clinical model, and a combined model were constructed and validated using a receiver operating characteristic (ROC) curve. Finally, Delong's test was used to compare the three models. RESULTS: The radiomics model achieved an AUC of 0.70 (95 % CI: 0.62-0.78) in the training group and 0.60 (95 % CI: 0.45-0.76) in the validation group. RECIST assessment results were screened from all clinical characteristics as independent factors for MPR with multivariate logistic regression analysis. The AUC of the clinical model for predicting MPR was 0.66 (95 % CI: 0.59-0.73) in the training group and 0.77 (95 % CI: 0.66-0.87) in the validation group. The combined model with combined radiomics and clinicopathological characteristics achieved an AUC was 0.76 (95 % CI: 0.68-0.84) in the training group, and 0.80 (95 % CI: 0.67-0.92) in the validation group. Delong's test showed that the AUC of the combined model was significantly higher than that of the radiomics model alone in both the training group (P = 0.0067) and the validation group (P = 0.0009).The calibration curve showed good agreement between predicted and actual MPR. Clinical decision curve analysis showed that the combined model was superior to radiomics alone. CONCLUSIONS: Radiomics model can predict MPR in NSCLC after neoadjuvant chemoimmunotherapy with similar accuracy to RECIST assessment criteria. The combined model based on pretreatment CT radiomics and clinicopathological features showed better predictive power than independent radiomics model or independent clinicopathological features, suggesting that it may be more useful for guiding personalized neoadjuvant chemoimmunotherapy treatment strategies.

Real-World Data on Pathological Response and Survival Outcomes After Neoadjuvant Chemotherapy in HER2-Low Breast Cancer Patients.

BACKGROUND: Data on the pathological responses and survival outcomes after neoadjuvant chemotherapy (NACT) in human epidermal growth factor receptor-2 (HER2)-low breast cancer (BC) are lacking. This study aims to investigate this topic in the real world. METHODS: Clinicopathological data from 819 HER2-negative BC patients who underwent NACT between 2010 and 2020 were retrospectively retrieved from the Shanghai Jiaotong University Breast Cancer Database. These patients were categorized into HER2-low and HER2-0 groups. Logistic analyses were conducted to identify predictors of complete pathological response (pCR) and breast pCR. Cox regression analyses were conducted to assess the factors associated with disease-free survival (DFS) and overall survival (OS). Kaplan-Meier (K-M) curves were generated to compare DFS and OS between HER2-low BC and HER2-0 BC. RESULTS: Of the 819 BC patients, 669 (81.7%) had HER2-low tumors, and 150 (18.3%) had HER2-0 tumors. HER2-low BC had a significantly higher ratio of ER ≥ 10%, PR ≥ 20%, and Ki67 ≥ 15% than HER2-0 BC. A significantly higher breast pCR rate was observed in HER2-low BC than in HER2-0 BC (13.6% and 7.3%, respectively, P = .036). Age, HER2 status (low or 0), Ki67, and surgery options were associated with breast pCR in HER2-negative BC. In HER2-low BC, the pCR rate of ER ≥ 10% BC was significantly lower than that of ER < 10% BC, but the DFS and OS of ER 10% BC were significantly higher. The K-M curve showed no significant differences in DFS or OS between HER2-low and HER2-0 BC. Cox regression revealed that ER expression and histological grade (III vs. I∼II) were significantly associated with survival in HER2-low BC. CONCLUSIONS: In this real-world data (RWD) study, a significantly higher breast pCR rate was found in HER2-low BC than in HER2-0 BC, although there was no significant difference in survival. Moreover, ER expression had a significant prognostic impact on HER2-low BC.

Can the Pathological Response in Patients with Locally Advanced Gastric Cancer Receiving Neoadjuvant Treatment Be Predicted by the CEA/Albumin and CRP/Albumin Ratios?

Background: The purposes of neoadjuvant chemotherapy are to tumor size to improve the tumor removal rate, extend survival, and prevent metastasis. In this study, the importance of CRP/albumin ratio and CEA/albumin ratio in the prediction of neoadjuvant treatment response in gastric cancer patients was evaluated. Methods: This study retrospectively included 135 gastric cancer patients who received neoadjuvant chemotherapy at Çukurova University Balcali Hospital between January 2018 and December 2023. Preoperative CRP/albumin and CEA/albumin ratios were compared according to treatment response and multivariate logistic regression analysis was performed to determine the potential importance of these ratios in predicting pathological response. Results: The mean age of the 135 patients was 58.79 ± 10.83 (min = 26-max = 78). The CRP/albumin and CEA/albumin ratios were found to be significantly lower in patients who did not respond to neoadjuvant therapy. Each 1-unit increase in the CRP/albumin ratio was associated with a 1.16-fold decrease in the odds of pathological complete response to neoadjuvant therapy. Both CRP/albumin and CEA/albumin ratios were found to be significant in distinguishing neoadjuvant therapy response. The optimal cut-off value was 2.74 for the CRP/albumin ratio (sensitivity = 60%, specificity = 78.4%) and 1.40 for the CEA/albumin ratio (sensitivity = 74.2%, specificity = 67.6%). Values below these cut-off points favored neoadjuvant therapy response. Pathological complete response to neoadjuvant therapy was 4.75 times higher in patients with a CRP/albumin ratio below 2.74 and 5.14 times higher in patients with a CEA/albumin ratio below 1.40. Conclusions: Findings demonstrate that in patients with locally advanced gastric cancer receiving neoadjuvant treatment, CRP/Albumin and CEA/Albumin ratios are significant markers of pathological response.

Effect of Tumor Regression Grade on Survival and Disease-Free Interval in Patients Operated on for Locally Advanced Rectal Cancer.

INTRODUCTION: Colorectal cancer is the fourth leading cause of cancer-related death in both men and women in our population. In this regard, rectal cancer accounts for more than half of colorectal cancer deaths, and its incidence is expected to increase in the coming years. There have been significant changes in neoadjuvant therapy regimens, with promising results, as demonstrated by the recent RAPIDO and PRODIGE23 studies. Around 40% of patients diagnosed with locally advanced rectal cancer show some degree of response to neoadjuvant treatment, with complete tumor regression observed in up to one in five patients. MATERIALS AND METHODS: Retrospective observational study. A total of 181 patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy followed by surgery were analyzed. Clinical and pathological data were collected from the patients, including assessment of tumor regression through histopathological studies after surgery. The Mandard tumor regression grading system was used to categorize tumor response into different grades. RESULTS: The results showed a significant association between the degree of tumor regression and several important clinical outcomes. Specifically, patients with higher tumor regression had significantly better disease-free survival than those with less regression (p = 0.004). In addition, tumor regression was also correlated with the incidence of local recurrence (p = 0.018) and distant metastasis (p = 0.032). These associations suggest that tumor responsiveness to neoadjuvant therapy may influence the long-term progression of the disease. Regarding tumor deposits and the presence of lymphadenopathy, these factors were also found to be significantly associated with clinical outcomes. Patients with tumor deposits had a higher incidence of local recurrence (p = 0.025) and distant metastases (p = 0.041), while the presence of lymphadenopathy increased the risk of local recurrence (p = 0.013). These findings highlight the importance of evaluating not only tumor regression but also other pathological markers to predict prognosis and guide clinical management. CONCLUSIONS: The degree of tumor regression was not an independent predictor of survival compared to other variables such as nodal stage and presence of tumor deposits. This indicates that while tumor regression is an important factor, other elements also play a crucial role in determining the prognosis of patients with locally advanced rectal cancer. This study provides additional evidence for the importance of tumor regression, tumor deposits, and lymphadenopathy as predictors of clinical outcomes in patients with rectal cancer treated with neoadjuvant chemoradiotherapy.

Prognostic value of neutrophil-to-lymphocyte ratio (NLR) and platelet-neutrophil (PN) index in locally advanced rectal cancer patients: a retrospective cohort study.

Introduction: In locally advanced rectal cancers (LARC), tumour node metastasis (TNM) staging is far from optimal. The authors aimed to investigate the value of previously described circulating biomarkers as predictors of prognosis. Methods: Retrospective analysis of 245 LARC patients diagnosed between January 2010 and December 2022, who underwent neoadjuvant chemoradiotherapy and surgery at two centres. A Cox regression and Kaplan-Meier analysis were performed. Results: Post-treatment platelet-to-lymphocyte ratio (PLR) predicted pathological complete response. The neutrophil-to-lymphocyte ratio (NLR) in two timepoints of the treatment significantly predicted overall survival, whereas the platelet-neutrophil (PN) index significantly predicted disease-free survival. In pathological stage II, the PN index predicted patients with a higher risk of disease-free survival. Conclusion: Blood parameters might allow the definition of subgroups of risk beyond TNM for the application of different therapeutic strategies.

Prognostic value of pathological nodal burden after neoadjuvant chemotherapy in initially cN0-1 breast cancer patients: a dual-center, 10-year survival analysis.

Background: There is an interest in performing de-escalating axillary surgery after neoadjuvant chemotherapy (NAC). However, the significance of residual axillary node disease after NAC has not been well studied. Objectives: To investigate the pathological residual axillary lymph node tumor burden (ypN) of patients with initial clinical nodal stage cN0-1 breast cancer after NAC and determine its prognostic value. Design: Initial cN0-1 breast cancer patients who received NAC followed by axillary surgery at the First Hospital of Jilin University and the First Affiliated Hospital of Xi'an Jiaotong University between January 2011 and December 2019 were included. Methods: Survival outcomes were compared according to different clinical and pathological stage and nodal response to NAC. The main outcomes were disease-free survival (DFS) and overall survival (OS). Factors associated with survival were defined by Cox regression analysis. Results: A total of 911 patients were included, among whom 260 had cN0 and 651 had cN1 tumors. After NAC, 410 patients were ypN0, and another 501 were ypN+. The median follow-up time was 63 months. There was no significant difference in DFS or OS between the cN0 and cN1 groups in hormone receptor positive (HR+)/human epidermal growth factor receptor 2 positive (HER2+) and HR-/HER2- subtypes; instead, ypN status was significantly related to DFS and OS. In HR+/HER2- subtype, both cN and ypN stages did not show significant survival differences, but the ypN number and the nodal response to NAC showed significant prognostic value (p < 0.05). Among HR-/HER2+ patients, all cN status, ypN status, ypN number, and nodal response were significantly associated with survival (p < 0.05). Furthermore, tumor biology, axillary surgery, ypN status, pathological tumor size, and radiotherapy were independent prognostic factors for DFS and OS. Conclusion: The ypN status after NAC provide more prognostic information than the initial cN stage in cN0-1 patients, and the surgical axillary staging after NAC may have high clinical value.

Transforming breast cancer care: harnessing the power of artificial intelligence and imaging for predicting pathological complete response. a narrative review.

This narrative review explores the transformative potential of Artificial Intelligence (AI) and advanced imaging techniques in predicting Pathological Complete Response (pCR) in Breast Cancer (BC) patients undergoing Neo-Adjuvant Chemotherapy (NACT). Summarizing recent research findings underscores the significant strides made in the accurate assessment of pCR using AI, including deep learning and radiomics. Such AI-driven models offer promise in optimizing clinical decisions, personalizing treatment strategies, and potentially reducing the burden of unnecessary treatments, thereby improving patient outcomes. Furthermore, the review acknowledges the potential of AI to address healthcare disparities in Low- and Middle-Income Countries (LMICs), where accessible and scalable AI solutions may enhance BC management. Collaboration and international efforts are essential to fully unlock the potential of AI in BC care, offering hope for a more equitable and effective approach to treatment worldwide.

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

BACKGROUND: The 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. METHODS: We 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). RESULTS: Single-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. CONCLUSIONS: This 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.

Prognostic significance of a pathological response in metastatic lymph nodes of patients with gastric cancer who underwent neoadjuvant chemotherapy followed by surgery.

PURPOSE: To grade the pathological response of lymph nodes (LNs) to neoadjuvant chemotherapy (NAC) in patients with locally advanced gastric cancer (LAGC) and investigate its prognostic significance. METHODS: This retrospective study included 196 patients who underwent NAC, followed by radical gastrectomy for LAGC between January 2010 and October 2019. Pathological responses were evaluated based on the proportion of residual tumor cells within the tumor area in the primary tumor (PT) and LNs and included the following categories: 1a (0%), 1b (< 10%), 2 (10-50%), and 3 (> 50%). RESULTS: Among 166 patients with clinically node-positive disease, 38/27/39/62 were classified as having LN regression grade (LRG) 1a/1b/2/3, respectively. Compared to LN non-responders (LRG 2 or 3), LN responders (LRG 1a or 1b) had significantly higher 5-year overall survival (72.5% vs. 19.0%, P < 0.001) and recurrence-free survival rates (67.8% vs. 22.2%, P < 0.001), irrespective of PT response. Furthermore, a multivariate analysis revealed that the LN response was an independent risk factor for the overall survival (hazard ratio [HR] 0.417, 95% confidence interval [CI] 0.181-0.962, P = 0.040) and recurrence-free survival (HR 0.490, 95% CI 0.242-0.991, P = 0.047), but not the PT response (P > 0.05). CONCLUSIONS: The pathological LN response may be a reliable prognostic prediction tool in patients with LAGC who received NAC.

Exploring treatment outcomes in Stage II-III rectal cancer patients undergoing neoadjuvant therapy at a tertiary care center in Pakistan: a comprehensive analysis of pathological outcomes.

BACKGROUND: Rectal cancer treatment has transformed in recent years, with neoadjuvant treatment (NT) and total neoadjuvant treatment (TNT) aiming to enhance pathological responses. This pioneering study in our country delves into rectal cancer management, offering crucial insights by examining pathological outcomes in patients treated with the NT and TNT approach, shaping the evolving landscape. METHODS: In this retrospective-cohort study spanning January 2017 to December 2022 at a tertiary care hospital in Pakistan, ethical approval was obtained to examine outcomes of two treatments. Patients were divided into TNT (chemoradiation and pre-surgery 5 FU-based chemotherapy) and NT (chemoradiation, surgery, and subsequent 5 FU-based chemotherapy). The primary end-point was response rates-no response, pathological complete response (pCR), near complete response (near CR), and partial response (PR). The Chi-Square Test for Independence assessed the association between treatment response and type (TNT or NT). Data analysis used STATA MP 64; significance was set at p < 0.05 for all two-tailed tests. RESULTS: We analyzed 77 patients, 60 underwent standard neoadjuvant chemoradiation, and 17 followed the total neoadjuvant approach. Predominantly male, most were > 65 with ECOG 0-1. The TNT group showed higher response rates (76% vs 62%, p = 0.039), with 40.38% achieving pCR. In the overall population, pCR and near-CR were similar (27.2% vs 26%), while PR were 14%. Treatment characteristics correlated significantly with chemotherapy type, concurrent chemoradiation, LVI, PNI, and T, N, M staging (p < 0.05). Median overall survival was not reached, and mean survival was 89.1 months (CI: 95.0 to 83.3). Side effects varied, with notable differences in neuropathy, diarrhea, oral mucositis, and thrombocytopenia between NT and TNT groups. CONCLUSION: Our study adds to evidence favoring neoadjuvant approaches in managing rectal cancer in pakistan. Demonstrating a favorable pcr rate, ongoing research with extended follow-up is essential, given the dynamic landscape of rectal cancer treatment for improved patient outcomes.

Association of pathological response with long-term survival outcomes after neoadjuvant immunotherapy: A meta-analysis.

BACKGROUND: Complete pathological response (pCR) and major pathological response (MPR) have been proven to have a close association with improved event-free survival (EFS) and overall survival (OS) for patients accepting chemotherapy or chemoradiotherapy. However, further study focusing on neoadjuvant immunotherapy is limited. Here we provided an updated and comprehensive evaluation of the association between pathological response and long-term survival outcomes at patient level and trial level for neoadjuvant immunotherapy. METHODS: We systematically searched and assessed studies in PubMed, Embase, the Cochrane Library and relevant conference abstracts from inception to June 1, 2023. Studies reported EFS/OS results by pCR/MPR status were eligible. RESULTS: Forty-three studies comprising a total of 4100 patients were eligible for the analysis, which included 39 studies for the patient-level analysis and 5 randomized controlled trials for the trial-level analysis. Our results highlighted that pCR was associated with improved EFS (HR, 0.48 [95 % CI, 0.39-0.60]) and OS (HR, 0.55 [95 % CI, 0.41-0.74]). The magnitude of HRs by MPR status were similar to the results by pCR status (EFS HR, 0.31 [95 % CI, 0.18-0.53]) and OS HR, 0.43 [95 % CI, 0.19-0.96]). However, no association between pCR and EFS at trial level was found (P = 0.8, R2 = 0). CONCLUSION: Our meta-analysis demonstrates a strong association between pathological response and long-term survival outcomes at patient level across studies applying neoadjuvant immunotherapy in most solid tumors but we fail to validate the relationship at trial level. Therefore, an accepted surrogate endpoint applied to both patient and trial levels are waited for further search.

Prolonged interval to surgery following neoadjuvant chemoradiotherapy in locally advanced rectal cancer: A meta-analysis of randomized controlled trials.

BACKGROUND: Long-course neoadjuvant chemoradiotherapy (NCRT), followed by surgery after an interval of 6-8 weeks, represents standard of care for patients with locally advanced rectal cancer (LARC). Increasing this interval may improve rates of complete pathological response (pCR) and tumour downstaging. We performed a meta-analysis comparing standard (SI, within 8 weeks) versus longer (LI, after 8 weeks) interval from NCRT to surgery. METHODS: PubMed, Embase, and Cochrane databases were searched up to 31 August 2022. Randomized controlled trials (RCTs) comparing SI with LI after NCRT for LARC were included. The primary endpoint was pCR rate. Secondary endpoints included rates of R0 resection, circumferential resection margin positivity (+CRM), TME completeness, lymph node yield (LNY), operative duration, tumour downstaging (TD), sphincter preservation, mortality, postoperative complications, surgical site infection (SSI) and anastomotic leak (AL). Random effects models were used to calculate pooled effect size estimates. RESULTS: Four RCTs encompassing 867 patients were included. There were 539 males (62.1%). LI was associated with a higher pCR rate (OR 0.61, 95%CI â€‹= â€‹0.39-0.95, p â€‹= â€‹0.03), and more TD (OR 0.60, 95%CI â€‹= â€‹0.37-0.97, p â€‹= â€‹0.04) compared to SI. However, there was no difference in rates of R0 resection (p â€‹= â€‹0.87), +CRM (p â€‹= â€‹0.66), sphincter preservation (p â€‹= â€‹0.26), incomplete TME (p â€‹= â€‹0.49), LNY (p â€‹= â€‹0.55), SSI (p â€‹= â€‹0.33), AL (p â€‹= â€‹0.20), operative duration (p â€‹= â€‹0.07), mortality (p â€‹= â€‹0.89) or any surgical complication (p â€‹= â€‹0.91). CONCLUSIONS: A LI to surgery after NCRT for LARC increases pCR and TD rates. Local recurrence or survival were not assessed due to unavailable data. We recommend deferring TME until after an interval of 8 weeks following completion of NCRT.

Prognosis of a Heterogeneous TRG Pathological Response to Neoadjuvant Chemotherapy in Patients who Undergo Resection for Colorectal Liver Metastases.

BACKGROUND: Optimal management of colorectal liver metastasis (CRLM) is based on a combination of chemotherapy and surgical resection. The tumor regression grade (TRG) score is a histological scoring system to evaluate response to chemotherapy. The prognosis of a heterogeneous response in cases of multiple metastases has not been evaluated according to the TRG score. PATIENTS AND METHODS: All patients who underwent liver resection for multiple CRLM after neoadjuvant chemotherapy in two tertiary centers from January 2015 to April 2019 were retrospectively included. Oncological characteristics and outcome between TRG 1-2-3 (good response group), TRG 4-5 (poor response group) and heterogeneous TRG (good and poor TRG among different lesions within the same patient) groups were compared. RESULTS: Among the 327 patients included, 134 (41.0%) had good response (TRG 1-2-3), 120 (36.7%) had poor response (TRG 4-5), and 73 (22.3%) had heterogeneous response. The type and number of cycles of chemotherapy, k-Ras mutational status, and tumor number or size did not differ between the three groups. Use of irinotecan-based and anti-VEGF neoadjuvant therapy was associated with better TRG response [irinotecan-based: hazard ratio (OR) = 1.744; p = 0.045; anti-VEGF neoadjuvant therapy: 2.054; p = 0.005). Overall survival (OS) was higher in the 1-2-3 TRG group than in the heterogeneous TRG group (2-year OS = 81.3% vs. 60.3%, respectively; p = 0.003) and the 4-5 TRG group (2-year OS = 81.3% vs. 55.0%, respectively; p = 0.012) and similar between the heterogeneous and 4-5 TRG groups. CONCLUSIONS: The proportion of heterogeneous pathological response according to TRG is 22.3%, and the prognosis is comparable to that of poor pathological response.