Pathologic Tumor Response Research Articles

Dynamics of cell-free tumor DNA correlate with early MRI response during chemoradiotherapy in rectal cancer

BackgroundIn locally advanced rectal cancer, the prediction of tumor response during and after neoadjuvant treatment remains challenging. In terms of organ preservation, adaptive radiotherapy, and intensified (total) neoadjuvant therapies, biomarkers are desirable for patient stratification.MethodsIn 16 patients, weekly blood samples (n = 86) to detect cell-free tumor DNA (ctDNA) during long-course neoadjuvant chemoradiotherapy were analyzed. Data were correlated with initial tumor volumes, MRI response in week 2 and 5 of radiotherapy as well as with pathologic tumor response after resection and outcome parameters.ResultsMost patients showed decreasing ctDNA during the course of radiochemotherapy. However, we found heterogenous dynamics of ctDNA and could identify three groups: (1) decline (2) no clear decline and/or late shedding (3) persistence of ctDNA. In seven patients we could detect significant amounts of ctDNA in week 5 or week 6 of treatment. In our pilot cohort, we did not find significant correlations of ctDNA dynamics with pathologic response or outcome parameters. However, patients with distinct decline of ctDNA had larger tumor volumes prior to treatment, and MRI imaging in week 2 and 5 revealed bigger absolute decrease of tumor volumes. If significant levels of ctDNA were found in week 5 and / or 6, patients showed less absolute tumor volume decrease in week 2 and 5.ConclusionsWeekly measurement of ctDNA during radiochemotherapy is feasible and might represent a promising biomarker. Bigger initial primary tumors showed different ctDNA shedding profiles compared with smaller primary tumors and correlations of ctDNA dynamics with early imaging response were found.

Prognostic and Predictive Markers for Early Stage Triple-Negative Breast Cancer Treated With Platinum-Based Neoadjuvant Chemotherapy.

Emerging evidence has indicated possible efficacy benefit of platinum-based chemotherapy as neoadjuvant treatment for invasive ductal carcinoma triple-negative breast cancer (TNBC). However, it has not been endorsed by current guidelines due to highly controversial results. Present study aims to investigate predictive and prognostic roles concerning single nucleotide polymorphisms (SNPs) in XRCC1 and BRCA1, BRCA2 genes for early stage TNBC patients that received platinum-based neoadjuvant treatment. We prospectively enrolled women with stage IIB-IIIB TNBC that had progressed on neoadjuvant taxane and anthracycline-based chemotherapy at Xinjiang Medical University Affiliated Cancer Hospital. Tumor response and pathological complete response (pCR) rate were assessed. Invasive disease-free survival (iDFS) and overall survival (OS) were analyzed. Patients' blood samples were subject to Sanger sequencing to genotype XRCC1 Arg194Trp and Arg399Gln, BRCA1 s1799949, and BRCA2 rs206115. Univariate and multivariate logistic regressions were employed to investigate associations between SNPs and clinical characteristics with treatment response and pCR. A total of 45 patients were enrolled. The cohort showcased ORR of 44.4%, pCR of 28.9%, median iDFS of 22 months, and a 3-year OS of 73.3%. The A/G and G/G genotypes of BRCA1 rs1799949, and the T/T genotype of BRCA2 rs206115 were associated with higher responsive rate. Histologic grade of III and Ki67 expression > 65% were associated with low responsive rate. Moreover, the A/G genotype of BRCA1 rs1799949 and T/T genotype of BRCA2 rs206115 correlated to high pCR. The histologic III and T4 stage correlated to inferior iDFS. Carrier of BRCA1 rs1799949 G/G had the most favorable OS, carriers of A/A showed the poorest OS, and those with A/G genotype showed an intermediate OS. Platinum-based chemotherapy might serve as a therapeutic option for TNBC patients who were resistant to anthracycline- and taxane-based neoadjuvant therapy. Our study identified several genetic and clinical features that might function as prognostic and predictive markers.

Maximum standardised uptake value of positron emission tomography as a predictor of oesophageal cancer outcomes

ObjectivesThis study aimed to analyse the value of pre-operative 18F-fluorodeoxyglucose positron emission tomography (PET)-computed tomography that can predict tumour pathological complete response, tumour histology grade, overall survival, and recurrence-free survival in patients with locally advanced oesophageal squamous cell carcinoma who underwent neoadjuvant chemoradiotherapy (NCRT) followed by surgery.MethodsWe retrospectively reviewed the cases of patients with locally advanced oesophageal squamous cell carcinoma undergoing NCRT followed by surgery. Patients who did not undergo PET within 3 months of surgery were excluded. We set a pre-operative PET maximum standardised uptake value (SUVmax) of > 5 as the threshold and classified the patients into two groups. We analysed the tumour response and histology grade, and compared the overall survival and recurrence-free survival between the two groups.ResultsThis cohort included 92 patients with oesophageal squamous cell carcinoma who underwent NCRT followed by surgery; 49 patients had a pre-operative PET SUVmax < 5, and 43 patients had a pre-operative PET SUVmax > 5. The patients’ pre-operative PET SUVmax correlated with tumour histology, ypT stage, and tumour response. Patients with a pre-operative SUVmax < 5 had better 2-year-overall survival (78% vs. 62%, P < 0.05) and 2-year recurrence-free survival (62% vs. 34%, P < 0.05) than those with a pre-operative SUV > 5.ConclusionsPre-operative SUVmax may be useful to predict tumour response, survival, and recurrence in patients with locally advanced oesophageal squamous cell carcinoma who undergo NCRT followed by surgery.

Pathological response following neoadjuvant immune checkpoint inhibitors in patients with hepatocellular carcinoma: a cross-trial, patient-level analysis

Neoadjuvant use of immune checkpoint inhibitors (ICIs) before liver resection results in pathological tumour regression in patients with hepatocellular carcinoma. We aimed to describe the characteristics of pathological responses after preoperative ICI therapy for hepatocellular carcinoma and to evaluate the association between the depth of tumour regression and relapse-free survival. In this cross-trial, patient-level analysis, we performed a pooled analysis of data from patients with hepatocellular carcinoma receiving ICI therapy before liver resection as part of a global collaborative consortium (NeoHCC) of five phase 1 and 2 clinical trials and standardised observational protocols conducted in 12 tertiary referral centres across the USA, UK, and Taiwan. Eligible patients were adults (aged ≥18 years) diagnosed with hepatocellular carcinoma by tissue core biopsy before treatment initiation, a Liver Imaging Reporting and Data System score of 5 on imaging, or both, with an Eastern Cooperative Oncology Group performance status score of 0-1, and no extrahepatic spread or previous ICI treatment. Pathological response was measured as the percentage of non-viable tumour in the resected surgical specimen, with major pathological response corresponding to at least 70% tumour regression and pathological complete response corresponding to 100% tumour regression. We correlated pathological response with radiological overall response using RECIST criteria (version 1.1) and relapse-free survival, and evaluated the threshold of tumour regression that could be optimally associated with relapse-free survival. At data cutoff on Jan 31, 2024, 111 patients were included in the study, of whom data on pathological response were available for 104 (94%) patients. Patients received treatment from Oct 5, 2017, to Nov 15, 2023, mostly ICI combinations (76 [69%]), for a median of 1·4 months (IQR 0·7-2·9). 87 (78%) patients were men and 24 (22%) were women. Most patients had underlying viral chronic liver disease (73 [66%]) and Barcelona Clinic Liver Cancer stage A hepatocellular carcinoma (61 [55%]), without portal vein thrombosis (87 [78%]). We observed major pathological response in 33 (32%) patients and pathological complete response in 19 (18%) patients. Radiological overall response was associated with major pathological response, with 23 (74%) of 31 patients with radiological response showing major pathological response compared with ten (14%) of 73 patients without radiological response (p<0·0001). However, ten (30%) of 33 major pathological responses were not predicted by radiological response. After a median follow-up of 27·2 months (95% CI 22·3-32·1), median relapse-free survival for the whole cohort was 43·6 months (95% CI 28·3-not evaluable). Relapse-free survival was significantly longer in patients with major pathological response than in those who did not have a major pathological response (not reached [95% CI not evaluable-not evaluable] vs 28·3 months [12·8-43·8]; hazard ratio 0·26 [0·10-0·66]; p=0·0024) and in patients with pathological complete response than in those who did not have a pathological complete response (NR [95% CI not evaluable-not evaluable] vs 32·8 months [15·0-50·5]; 0·19 [0·05-0·78]; p=0·010). Unbiased recursive partitioning of the cohort for the risk of relapse, death, or both identified a threshold of 90% as the optimal cutoff of pathological tumour regression to predict improved relapse-free survival. The extent of tumour regression following neoadjuvant ICI therapy could identify patients with improved relapse-free survival following liver resection. The threshold of at least 90% tumour regression should be validated for its surrogate role for relapse-free survival in phase 3 randomised controlled trials. None.

Classification of Neoadjuvant Therapy Response in Patients With Colorectal Liver Metastases Using Contrast-Enhanced Ultrasound—With Histological Pathology as the Gold Standard

ObjectiveTo evaluate the response to neoadjuvant therapy in patients with colorectal liver metastases (CRLMs) using ultrasound(US) and contrast-enhanced ultrasound(CEUS), with correction to the tumor regression grade (TRG) of pathological results. MethodsThis study included patients with resectable CRLMs admitted from February to December 2022. After at least 4 cycles neoadjuvant therapy, all the patients received US and CEUS examinations within two weeks before hepatectomy. CEUS clips were postprocessed with color parameter imaging (CPI) and microflow imaging (MFI) analysis. Logistic regression analyses were used to develop an evaluation Nomogram. Ultrasound-based model was constructed to discriminate between the response (TRG1/2/3) and nonresponse (TRG4/5) groups at the lesion level. The model's predictive ability was evaluated using the C index and calibration curve, with decision curve analysis assessing the Nomogram's added value. ResultsThe study analyzed 105 CRLM lesions (the lesion with the highest diameter analyzed for each patient), with 43.8% showing a response to therapy. Univariate analysis identified calcification on US (p = 0.039), CEUS enhancement degree (p < 0.001), CEUS enhancement pattern (p<0.001), CEUS washout type (p < 0.001), CEUS necrosis (p < 0.001), CPI feeding artery (p = 0.003) and MFI pattern (p < 0.001) were significantly associated with TRG. The multivariate analysis showed CEUS enhancement pattern (p = 0.026), CEUS washout type (p = 0.018) and CEUS necrosis (p = 0.005) were independently associated with the neoadjuvant therapy response. A Nomogram with the three independent predictors was developed, with an AUC of 0.898. ConclusionThe ultrasound-based model provided accurate evaluation of pathological tumor response to preoperative chemotherapy in patients with CRLM, and may help to decide the individualized treatment strategy.

Pathological complete response of locally advanced triple-negative breast cancer: case report

Background. Triple-negative breast cancer is the most aggressive molecular subtype among breast malignancies. Due to the high proliferative activity of tumor cells and the lack of targets for targeted therapy, neoadjuvant chemotherapy plays the main role in complex treatment of this subtype. The optimal time to start neoadjuvant chemotherapy is defined as less than 8 weeks. Delays in time to treatment initiation may adversely affect treatment outcomes, as well as cause local or systemic disease progression. Achieving complete pathological response after neoadjuvant chemotherapy reduces the relative risk of relapse by more than 70 %, which, in turn, leads to a significant improvement in long-term survival of these patients. Description of the clinical case. A 32-year-old woman came to the clinic 15 months after being diagnosed with triple-negative breast cancer. The patient was treated with alternative medicine methods for 15 months, and upon admission to the hospital, the patient had pronounced local tumor growth with massive decay, tumor lysis syndrome and nutritional disorders. We decided to perform neoadjuvant chemotherapy: 12 cycles of weekly paclitaxel + carboplatin, followed by 4 cycles of dose-dense doxorubicin + cyclophosphamide. Chemotherapy resulted in a significant reduction in tumor size and improvement of health status of the patient. There were no clinically significant side effects requiring hospitalization or dose reduction. Upon completion of neoadjuvant treatment, the patient underwent mastectomy. The histological examination revealed a complete pathological response of the primary tumor and regional lymph nodes. The patient underwent adjuvant external beam radiation therapy. The patient is alive 3 years after diagnosis and 1.5 years after treatment completion. She plans delayed breast reconstruction with contralateral breast augmentation. Conclusion. This is a rare case of locally advanced triple-negative breast cancer with pathological complete response to neoadjuvant chemotherapy 15 months after diagnosis.

The Relationship between Treatment Response and Overall Survival in Borderline, Non-Resectable and Resectable Pancreatic Cancer Patients Treated with Neoadjuvant FOLFIRINOX.

Background: The National Comprehensive Cancer Network (NCCN)-recommended treatment for patients with borderline-resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC) involves a combination of neoadjuvant FOLFIRINOX chemotherapy and the curative surgical resection of the tumor. This study seeks to identify the clinical, radiological, laboratory, and pathologic predictors that can anticipate the oncological outcomes of patients. Methods: In this study, we conducted a retrospective analysis of patients who had undergone curative surgical resection for BRPC, LAPC, or resectable disease with high-risk features after receiving neoadjuvant FOLFIRINOX at two institutions. We evaluated by means of multivariate analysis whether clinical and laboratory response, tumor markers, radiological response, and pathologic tumor response grade correlated with overall survival (OS) and disease-free survival (DFS). Results: The study enrolled a total of 70 patients with BRPC, LAPC, and resectable disease with high-risk features who underwent resection after neoadjuvant FOLFIRINOX. Age above 65 years and fewer than nine cycles of chemotherapy (OR 4.2; 95% CI 1.4-12.0; p-value 0.007); locally advanced tumors after neoadjuvant treatment (NAT) (OR 7.0; 95% CI 1.9-25.7; p-value 0.003); and lymph node disease and histological tumor regression grade 2 and 3 (OR 4.3; 95% CI 0.9-19.2; p-value 0.05) were risk factors linked to adverse OS and DFS. The median OS and DFS were 33 (22-43.9) months and 16.5 (11.3-21.6) months, respectively. Conclusions: Classification as a LA tumor after NAT was the only preoperative radiological factor that predicted adverse survival in patients undergoing curative surgery after NAT. Other clinical, biochemical, and radiological measures of response were not found to predict OS. Patient age, the cumulative administration of more than eight cycles of chemotherapy, and a significant pathological response were associated with better OS. The results of this study are important for treatment decision-making and prognostication in patients with BRPC and LAPC.

754. PATHOLOGICAL RESPONSE PREDICTS EFFICACY OF ADJUVANT FLOT CHEMOTHERAPY IN GASTROESOPHAGEAL CANCER: AN INTERNATIONAL COHORT STUDY

Abstract Background Perioperative FLOT-based chemotherapy is the current standard of care for all patients with locally-advanced gastroesophageal cancer. However, many patients are unable to complete all planned adjuvant FLOT cycles due to treatment related toxicity and diminished performance status after radical surgery. Within this context, it is unclear whether adjuvant FLOT will improve oncological outcomes for patients with cancers that either don’t respond or respond exceptionally well to neoadjuvant FLOT. To facilitate clinical decision-making, we examined whether pathological response to neoadjuvant FLOT can guide its adjuvant use. Methods Prospectively collected data from 43 centres across 12 countries was analysed. Patients with non-metastatic gastroesophageal adenocarcinoma who received neoadjuvant FLOT followed by radical surgery between 2017-2022 were included. Pathological response was assessed using validated tumour regression grading (TRG) systems. All TRG were trichotomized into minimal responders (MR=worse TRG category), complete responders (CR=pathological complete response), and partial responders (PR=all TRG categories between MR and CR). Survival outcomes of patients who did and did not receive adjuvant FLOT within these cohorts were compared using Kaplan Meier and Cox regression analysis. These findings were validated using propensity score matched analysis. Results 1887 patients (MR n=459, CR n=221, PR n=1207) were evaluated. The median follow-up was 25.5 months. In the MR group, there was no DFS (HR=1.03, 95%CI 0.78-1.36) or adjusted-OS (HR=0.96, 95%CI 0.70-1.30) difference between those who did (n=272) and did not (n=187) receive adjuvant FLOT. In the CR group, there was no DFS (HR=0.88, 95%CI 0.41-1.85) or OS (HR=0.69, 95%CI 0.31-1.54) difference between those who did (n=136) and did not (n=85) receive adjuvant FLOT. In the PR group (adjuvant FLOT n=847, no adjuvant FLOT n=360), adjuvant FLOT conferred a significant DFS (HR=0.68, 95%CI 0.55-0.86) and OS (HR=0.55, 95%CI 0.44-0.69) benefit. Conclusions Pathological response to neoadjuvant FLOT predicts therapeutic efficacy to adjuvant FLOT. Only partial responders benefit from adjuvant treatment. Our findings challenge the current doctrine that perioperative FLOT should be applied to all patients regardless of pathological tumour response.

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.

Clinical outcomes and short-term survival of neoadjuvant immunochemotherapy for resectable esophageal cancer: a multi-center retrospective cohort study

Objective: The present retrospective cohort study aims to evaluate the efficacy and safety of neoadjuvant immunochemotherapy for resectable esophageal cancer and report the preliminary short-term survival. Methods: A multi-center, retrospective study was conducted concerning patients who received neoadjuvant PD-1 agents plus platinum-based chemotherapy between January, 2019 to January, 2022. The primary endpoint was the tumor pathologic complete response (pCR) rate. Results: Two hundred and thirteen patients with initial stage cI-IVA esophageal cancer who received neoadjuvant immunochemotherapy were identified. Complete tumor resection(R0) rate was 99.1%. The pCR rate was 31.9%, and the overall major pathological response rate was 49.8%. The 2-year DFS rate was 78.9% (95%CI: 72.9%-85.4%) and 2-years OS rate was 80.9% (95%CI: 75.3%-86.9%). The incidence of TRAEs and surgical complications rate were 68.5% and 35.2%, respectively. Conclusion: The PD-1 agents combined with chemotherapy in the neoadjuvant treatment for resectable stage I–IVA esophageal cancer had a high pCR rate as well as good short-term survival benefit and tolerable toxicity.

Dynamics of peripheral blood inflammatory index predict tumor pathological response and survival among patients with locally advanced non-small cell lung cancer who underwent neoadjuvant immunochemotherapy: a multi-cohort retrospective study.

Static tumor features before initiating anti-tumor treatment were insufficient to distinguish responding from non-responding tumors under the selective pressure of immuno-therapy. Herein we investigated the longitudinal dynamics of peripheral blood inflammatory indexes (dPBI) and its value in predicting major pathological response (MPR) in non-small cell lung cancer (NSCLC). A total of 147 patients with NSCLC who underwent neoadjuvant immunochemotherapy were retrospectively reviewed as training cohort, and 26 NSCLC patients from a phase II trial were included as validation cohort. Peripheral blood inflammatory indexes were collected at baseline and as posttreatment status; their dynamics were calculated as their posttreatment values minus their baseline level. Least absolute shrinkage and selection operator algorithm was utilized to screen out predictors for MPR, and a MPR score was integrated. We constructed a model incorporating this MPR score and clinical predictors for predicting MPR and evaluated its predictive capacity via the area under the curve (AUC) of the receiver operating characteristic and calibration curves. Furthermore, we sought to interpret this MPR score in the context of micro-RNA transcriptomic analysis in plasma exosomes for 12 paired samples (baseline and posttreatment) obtained from the training cohort. Longitudinal dynamics of monocyte-lymphocyte ratio, platelet-to-lymphocyte ratio, platelet-to-albumin ratio, and prognostic nutritional index were screened out as significant indicators for MPR and a MPR score was integrated, which was further identified as an independent predictor of MPR. Then, we constructed a predictive model incorporating MPR score, histology, and differentiated degree, which discriminated MPR and non-MPR patients well in both the training and validation cohorts with an AUC value of 0.803 and 0.817, respectively. Furthermore, micro-RNA transcriptomic analysis revealed the association between our MPR score and immune regulation pathways. A significantly better event-free survival was seen in subpopulations with a high MPR score. Our findings suggested that dPBI reflected responses to neoadjuvant immuno-chemotherapy for NSCLC. The MPR score, a non-invasive biomarker integrating their dynamics, captured the miRNA transcriptomic pattern in the tumor microenvironment and distinguished MPR from non-MPR for neoadjuvant immunochemotherapy, which could support the clinical decisions on the utilization of immune checkpoint inhibitor-based treatments in NSCLC patients.

Radiomic analysis reveals diverse prognostic and molecular insights into the response of breast cancer to neoadjuvant chemotherapy: a multicohort study

BackgroundBreast cancer patients exhibit various response patterns to neoadjuvant chemotherapy (NAC). However, it is uncertain whether diverse tumor response patterns to NAC in breast cancer patients can predict survival outcomes. We aimed to develop and validate radiomic signatures indicative of tumor shrinkage and therapeutic response for improved survival analysis.MethodsThis retrospective, multicohort study included three datasets. The development dataset, consisting of preoperative and early NAC DCE-MRI data from 255 patients, was used to create an imaging signature-based multitask model for predicting tumor shrinkage patterns and pathological complete response (pCR). Patients were categorized as pCR, nonpCR with concentric shrinkage (CS), or nonpCR with non-CS, with prediction performance measured by the area under the curve (AUC). The prognostic validation dataset (n = 174) was used to assess the prognostic value of the imaging signatures for overall survival (OS) and recurrence-free survival (RFS) using a multivariate Cox model. The gene expression data (genomic validation dataset, n = 112) were analyzed to determine the biological basis of the response patterns.ResultsThe multitask learning model, utilizing 17 radiomic signatures, achieved AUCs of 0.886 for predicting tumor shrinkage and 0.760 for predicting pCR. Patients who achieved pCR had the best survival outcomes, while nonpCR patients with a CS pattern had better survival than non-CS patients did, with significant differences in OS and RFS (p = 0.00012 and p = 0.00063, respectively). Gene expression analysis highlighted the involvement of the IL-17 and estrogen signaling pathways in response variability.ConclusionsRadiomic signatures effectively predict NAC response patterns in breast cancer patients and are associated with specific survival outcomes. The CS pattern in nonpCR patients indicates better survival.

Comparison of immunochemotherapy and chemotherapy alone in conversion therapy for locally advanced unresectable esophageal squamous cell carcinoma.

The clinical value of preoperative immunochemotherapy and simple chemotherapy induction regimen in the conversion therapy of locally advanced unresectable esophageal squamous cell carcinoma (ESCC) is still unclear. Retrospective analysis was conducted on patients with unresectable cT4b stage ESCC who underwent conversion surgery in our hospital from January 2020 to December 2022. According to the preoperative induction treatment plan, they were divided into induction immunochemotherapy group (iICT group) and induction chemotherapy group (iCT group). The conversion surgery rate, R0 resection rate, radiological and pathological tumor responses, safety, and short-term survival outcomes were analyzed. The results showed that a total of 199 patients with cT4b locally advanced unresectable ESCC who underwent preoperative induction therapy were included in this study. Among them, there were 64 cases (32.2%) in the iICT group, 135 cases (67.8%) in the iCT group. There was a statistically significant difference in objective response rate (73.5% vs 48.9%) and conversion surgery rate (81.3% vs 66.7%), between the iICT and iCT groups (P=0.001 and P=0.019). Among the two groups of patients who underwent surgery, there were statistically significant differences in R0 resection rate (94.2% vs 82.2%) and pathological complete remission rate (23.1% vs 6.7%) between the iICT and iCT groups (P=0.043 and P=0.004). And there was no statistically significant difference in the incidence of grade 3 and above between two groups (P=0.928). The 2-year EFS of the iICT group and iCT group were 76.4% and 42.4%, respectively, with statistically significant differences (P=0.006). Compared with simple chemotherapy, the combination of PD-1 inhibitors and chemotherapy can achieve better conversion surgery rate, tumor response and event-free survival in the conversion therapy of locally advanced unresectable ESCC.

Mapping of lymph node metastasis from esophageal squamous cell carcinoma after neoadjuvant treatment: a prospective analysis from a high-volume institution in China.

The study aimed to describe the prevalence of lymph node metastases per lymph node station for esophageal squamous cell carcinoma (ESCC) after neoadjuvant treatment. Clinicopathological variables of ESCC patients were retrieved from the prospective database of the Surgical Esophageal Cancer Patient Registry in West China Hospital, Sichuan University. A two-field lymphadenectomy was routinely performed, and an extensive three-field lymphadenectomy was performed if cervical lymph node metastasis was suspected. According to AJCC/UICC 8, lymph node stations were investigated separately. The number of patients with metastatic lymph nodes divided by those who underwent lymph node dissection at that station was used to define the percentage of patients with lymph node metastases. Data are also separately analyzed according to the pathological response of the primary tumor, neoadjuvant treatment regimens, pretreatment tumor length, and tumor location. Between January 2019 and March 2023, 623 patients who underwent neoadjuvant therapy followed by transthoracic esophagectomy were enrolled. Lymph node metastases were found in 212 patients (34.0%) and most frequently seen in lymph nodes along the right recurrent nerve (10.1%, 58/575), paracardial station (11.4%, 67/587), and lymph nodes along the left gastric artery (10.9%, 65/597). For patients with pretreatment tumor length of >4cm and non-pathological complete response of the primary tumor, the metastatic rate of the right lower cervical paratracheal lymph nodes is 10.9% (10/92) and 10.6% (11/104), respectively. For patients with an upper thoracic tumor, metastatic lymph nodes were most frequently seen along the right recurrent nerve (14.2%, 8/56). For patients with a middle thoracic tumor, metastatic lymph nodes were most commonly seen in the right lower cervical paratracheal lymph nodes (10.3%, 8/78), paracardial lymph nodes (10.2%, 29/285), and lymph nodes along the left gastric artery (10.4%, 30/289). For patients with a lower thoracic tumor, metastatic lymph nodes were most frequently seen in the paracardial station (14.2%, 35/247) and lymph nodes along the left gastric artery (13.1%, 33/252). The study precisely determined the distribution of lymph node metastases in ESCC after neoadjuvant treatment, which may help to optimize the extent of lymphadenectomy in the surgical management of ESCC patients after neoadjuvant therapy.

Clinical outcomes of neoadjuvant chemoradiotherapy followed by total mesorectal excision in locally advanced rectal cancer with mesorectal fascia involvement.

For the treatment of locally advanced rectal cancer (LARC), research on primary lesions with mesorectal fascia (MRF) involvement is lacking. This study analyzed the clinical outcomes and efficacy of dose-escalated neoadjuvant concurrent chemoradiotherapy (NCRT) to patients with LARC involving MRF. We retrospectively reviewed 301 patients who were diagnosed with LARC involving MRF and underwent NCRT followed by total mesorectal excision (TME). Patients who received radiotherapy (RT) doses of ≤50.4 Gy were defined as the non-boost group, while ≥54.0 Gy as the boost group. Pathological tumor response and survival outcomes, including intrapelvic recurrence-free survival (IPRFS), distant metastases-free survival (DMFS) and overall survival (OS), were analyzed. A total of 269 patients (89.4%) achieved a negative pathological circumferential resection margin and 104 (34.6%) had good pathological tumor regression grades. With a median follow-up of 32.4 months, IPRFS, DMFS, and OS rates at 5-years were 88.6%, 78.0%, and 91.2%, respectively. In the subgroup analysis by RT dose, the boost group included more advanced clinical stages of patients. For the non-boost group and boost group, 5-year IPRFS rates were 90.3% and 87.0% (p = 0.242), 5-year DMFS rates were 82.0% and 71.3% (p = 0.105), and 5-year OS rates were 93.0% and 80.6% (p = 0.439), respectively. Treatment related toxicity was comparable between the two groups (p = 0.211). Although this retrospective study failed to confirm the efficacy of dose-escalated NCRT, favorable IPRFS and pathological complete response was achieved with NCRT followed by TME. Further studies combining patient customized RT dose with systemic therapies are needed.

Clinical and Pathologic Tumor Response Following Response-guided Neoadjuvant Chemotherapy for Locally-advanced Breast Cancer in a Tertiary Hospital Breast Center in the Philippines

Clinical and Pathologic Tumor Response Following Response-guided Neoadjuvant Chemotherapy for Locally-advanced Breast Cancer in a Tertiary Hospital Breast Center in the Philippines

Neoadjuvant tislelizumab with afatinib for locally advanced head and neck squamous cell carcinoma (neoCHANCE-1): An open-label, single-arm, phase 2 study.

6073 Background: For patients with locally advanced head and neck squamous cell carcinoma (HNSCC), even receiving surgery with adjuvant radiotherapy or chemoradiotherapy, those remain at high risk of recurrence or metastasis. Neoadjuvant immunotherapy has been used in HNSCC, but provides only modest pathological response. Given single agent activity and unique mechanism of action of immune checkpoint inhibitors and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), we aimed to evaluate the antitumour activity and safety of neoadjuvant PD-1 blockade with EGFR inhibition in locally advanced HNSCC. Methods: This open-label, single-arm, phase 2 trial was done at a a tertiary hospital in China. Eligible patients were aged 18 years or older and had resectable HNSCC disease, had an Eastern Cooperative Oncology Group performance status of 0–1, had at least one measurable target lesion according to the RECIST 1.1, had no prior antitumor therapy for HNSCC. Patients received neoadjuvant treatment with intravenous tislelizumab (200 mg) on the first day of each 3 week, with totally two cycles and orally afatinib (30 mg) starting on the first treatment day and ending on the day before surgery, with totally six weeks, and then patients proceeded to receive surgical resection. The primary endpoint was major pathological response, defined as the presence of 10% or less residual viable tumour at the time of surgery. Results: A total of 25 patients were enrolled completed the neoadjuvant therapy. Eight of 23 evaluable patients exhibited a major pathological response (MPR) (35%; 95% confidence interval [CI], 16%—57%), of which four had a complete pathological response of primary tumor (17%, 95%CI, 5%—39%). The overall response rate was 48% (12/25, 95%CI: 28%—69%) and disease control rate was 100% (25/25, 95%CI: 86%—100%). Common grade 3—4 adverse events included diarrhea (5/25 [20%]), hypokalemia (4/25 [16%]) and rash (3/25 [12%]). No treatment related fatalities were observed. Immunologically, post-neoadjuvant treatment demonstrated increased CD3, CD8, and CD56 expression within the tumor microenvironment. The increase of CD8 and CD56 expression level was significant higher in patients achieving MPR, along with elevated circulatory NK cells at baseline, compared to those in patients achieving non-MPR. Conclusions: This study underscores encouraging antitumor activity, manageable toxicity profile and promising immune activation elicited by neoadjuvant tislelizumab plus afatinib for HNSCC, which deserves further assessment. Clinical trial information: NCT05517330 .

INTASYL PH-762: PD-1 intratumoral immunotherapy for cutaneous carcinoma.

TPS9620 Background: Immune checkpoint-targeted antibodies directed at PD-1 or PD-L1 block co-inhibitory receptors expressed by anti-tumor T cells, breaking immune tolerance against tumor cells and generating cancer immunity. Intratumoral (IT) immunotherapy aims to use the tumor as a ‘self-vaccine’. Local immune stimulation may induce robust priming of an anti-tumor immune response and generate abscopal tumor responses, mediated by circulating activated anti-tumor immune cells. Local delivery of immunotherapy minimizes systemic exposure and off-target toxicities and may decrease tumor size and improve surgical morbidity. PH-762 is an INTASYL compound designed to precisely silence PD-1 mRNA. INTASYL is a patented, self-delivering RNAi technology platform designed to impart specific properties to small interfering RNAs. PH-762’s unique structural and chemical modifications ensure an optimized cell and tissue uptake profile with IT administration. In vitro investigations have demonstrated efficient uptake of PH-762 by human T cells, silencing of PD-1 mRNA and subsequent protein reduction. Preclinical studies have shown that IT injections of murine-targeted PH-762 (mPH-762) can silence PD-1 mRNA in T cells within the tumor and increase the secretion of IFN-γ. mPH-762 was well tolerated at the maximum administered dose and treatment with mPH-762 provided robust and statistically significant inhibition of tumor growth. Toxicokinetic studies conducted in marmoset monkeys demonstrated that PH-762, when administered intravenously at doses of up to 147 mg/kg, is well-tolerated. No cytokine-release associated cytokines were detected in the plasma of treated monkeys at this dose. Methods: This open-label Phase 1 clinical study (NCT 06014086) is designed to evaluate the safety and tolerability of neoadjuvant use of IT PH-762 in cutaneous squamous cell carcinoma, melanoma, or Merkel cell carcinoma, to determine the pharmacokinetic profile of PH-762 after IT injection, to observe pathologic and immunologic tumor responses, and to determine the recommended dose for development. Escalating dose concentrations of PH-762 (from 1.14 mg/mL through 22.00 mg/mL) are tested serially in cohorts of 3 patients each. Patients receive IT PH-762 once weekly, 4 times over a 3-week period prior to surgical excision, which occurs 5 weeks after the initial injection. Following excision of the tumor, patients are followed for approximately 11 weeks. Tumor changes are evaluated per iRECIST criteria and pathological response. Immunological response in tumor tissue and blood samples are assessed as secondary endpoints. This clinical study, enrolling patients since November 2023, will establish the basis for continued clinical development of PH-762. Clinical trial information: 06014086.

Neoadjuvant chemoradiotherapy for thoracic esophageal squamous cell carcinoma: does everyone need it?

Objective. In accordance with clinical guidelines, neoadjuvant chemoradiotherapy (nCRT) is recommended as a beneficial option for treatment of thoracic esophageal squamous cell carcinoma (TESCC). However, some studies did not demonstrate potential benefits of nCRT. In this paper we compared treatment outcomes of surgery alone with preoperative CRT followed by surgery. Material and methods. Group 1 (n=147) consisted of patients who underwent surgery alone. Group 2 (n=3,337) was formed in the framework of the present systematic review and meta-analysis (15 publications captured 20 separate subgroups for analysis). Patients of group 2 received nCRT followed by esophagectomy. Overall survival (OS) and median OS were estimated. Results. The median OS was reached in group 1 and in 12 separate subgroups of group 2 (2310 of 3337 patients). In groups 1 and 2 the OS median estimates were 31.0 and 28.1, respectively (p=0.873). Respective 3-year and 5-year OS were 0.49 vs 0.48 (p=0.425) and 0.37 vs 0.41 (p=0.228). The median OS was not reached in 8 separate subgroups of group 2 (1027 of 3337 patients). In this case, group 2 patients had significantly higher 3- and 5-year OS compared to group 1 patients: 0.69 vs 0.49 (p=0.000) and 0.60 vs 0.37 (p=0.000), respectively. Pathological complete response to nCRT was associated with better survival. conclusion. nCRT is not appropriate for all patients with TESCC. Improved overall survival may be achieved in patients with a high grade of pathological tumor response to neoadjuvant treatment. Selective administration of nCRT based on highly probable prediction of complete tumor response seems promising. This concept needs further research.

Tumor-infiltrating lymphocytes as a predictor of axillary and primary tumor pathological response after neoadjuvant chemotherapy in patients with breast cancer: a retrospective cohort study

PurposeTumor-infiltrating lymphocytes (TILs) can predict complete pathological response (pCR) of tumor in the breast but not so well-defined in the axilla after neoadjuvant chemotherapy. Since axillary surgery is being increasingly de-escalated after NACT, we aimed to investigate the relationship between TILs and pCR in the axilla and breast, as well as survival amongst NACT patients.MethodsClinicopathological data on patients who underwent NACT between 2013 and 2020 were retrospectively examined. Specifically, pre-TILs (before NACT), post-TILs (after NACT) and ΔTIL (changes in TILs) were assessed. Primary endpoint was pCR and secondary endpoints were breast cancer-free interval (BCFI) and overall survival (OS).ResultsTwo hundred and twenty patients with nodal metastases were included. Overall axillary and breast pCR rates were 42.7% (94/220) and 39.1% (86/220), respectively, whereas the combined pCR rate was 32.7% (72/220). High pre-TILs (OR 2.03, 95% CI 1.02–4.05; p = 0.04) predicted axillary pCR whereas, high post-TILs (OR 0.33, 95% CI 0.14–0.76; p = 0.009) and increased ΔTILs (OR 0.25, 95% CI 0.08–0.79; p = 0.02) predicted non-axillary pCR. TILs were not a significant predictor for BCFI and OS.ConclusionsThis study supports the potential use of pre-TILs to select initially node-positive patients for axillary surgical de-escalation after NACT.