Targeted therapy guided by circulating tumor DNA analysis in advanced gastrointestinal tumors.

Although comprehensive genomic profiling has become standard in oncology for advanced solid tumors, the full potential of circulating tumor DNA (ctDNA)-based profiling in capturing tumor heterogeneity and guiding therapy selection remains underexploited, marked by a scarcity of evidence on its clinical impact and the assessment of intratumoral heterogeneity. The GOZILA study, a nationwide, prospective observational ctDNA profiling study, previously demonstrated higher clinical trial enrollment rates using liquid biopsy compared with tissue screening. This updated analysis of 4,037 patients further delineates the clinical utility of ctDNA profiling in advanced solid tumors, showcasing a significant enhancement in patient outcomes with a 24% match rate for targeted therapy. Patients treated with matched targeted therapy based on ctDNA profiling demonstrated significantly improved overall survival compared with those receiving unmatched therapy (hazard ratio, 0.54). Notably, biomarker clonality and adjusted plasma copy number were identified as predictors of therapeutic efficacy, reinforcing the value of ctDNA in reflecting tumor heterogeneity for precise treatment decisions. These new insights into the relationship between ctDNA characteristics and treatment outcomes advance our understanding beyond the initial enrollment benefits. Our findings advocate for the broader adoption of ctDNA-guided treatment, signifying an advancement in precision oncology and improving survival outcomes in advanced solid tumors.

ctDNA-based molecular residual disease and survival in resectable colorectal cancer.

The interim analysis of the CIRCULATE-Japan GALAXY observational study demonstrated the association of circulating tumor DNA (ctDNA)-based molecular residual disease (MRD) detection with recurrence risk and benefit from adjuvant chemotherapy (ACT) in resectable colorectal cancer (CRC). This updated analysis with a 23-month median follow-up, including 2,240 patients with stage II-III colon cancer or stage IV CRC, reinforces the prognostic value of ctDNA positivity during the MRD window with significantly inferior disease-free survival (DFS; hazard ratio (HR): 11.99, P < 0.0001) and overall survival (OS; HR: 9.68, P < 0.0001). In patients who experienced recurrence, ctDNA positivity correlated with shorter OS (HR: 2.71, P < 0.0001). The significantly shorter DFS in MRD-positive patients was consistent across actionable biomarker subsets. Sustained ctDNA clearance in response to ACT was an indicator of favorable DFS and OS compared to transient clearance (24-month DFS: 89.0% versus 3.3%; 24-month OS: 100.0% versus 82.3%). True spontaneous clearance rate with no clinical recurrence was 1.9% (2/105). Overall, our findings provide evidence for the utility of ctDNA monitoring for post-resection recurrence and mortality risk stratification that could be used for guiding adjuvant therapy.

Clinical impact of skeletal muscle mass and nutritional status in patients with recurrent or advanced gastric cancer treated with nivolumab.

Background This study aimed to evaluate the clinical impact of skeletal muscle mass and nutritional status in gastric cancer patients treated with nivolumab monotherapy as late-line treatment. Methods We conducted a multi-institutional retrospective study of 90 gastric cancer patients who previously received anti-PD-1 therapy (nivolumab). On computed tomography images captured before nivolumab induction, the skeletal muscle index (SMI, cm2/m2) was defined as the erector muscle area (cm2) divided by the height (m) squared. Patients were divided into two groups: those with SMI-high (n = 45) and those with SMI-low (n = 45). Prognostic nutritional index (PNI) was also calculated before nivolumab induction. The associations of SMI and PNI with response rate (RR), progression-free survival (PFS), overall survival (OS), disease control rate (DCR), and safety were analyzed. Results The cutoff values for SMI were determined as 13.45 for males and 10.41 for females. SMI-high was significantly associated with a higher RR (odds ratio = 12.36, p = 0.02) and DCR (odds ratio = 2.97, p = 0.02). Although not significant, PNI-high also tended to be associated with a higher RR. Multivariate analysis showed that SMI-high was independently associated with a higher RR and higher DCR in gastric cancer. Moreover, prognostic analyses revealed that SMI-high (log-rank test p = 0.008) and PNI-high (log-rank test p = 0.0008) were significantly associated with longer OS since nivolumab induction. SMI-high was also associated with longer PFS (log-rank test p = 0.03). There were no significant differences in irAE between SMI-low and SMI-high. Conclusions SMI and PNI were associated with nivolumab efficacy in gastric cancer patients. Management of skeletal muscle loss and nutritional status in gastric cancer patients who will receive nivolumab would be beneficial to enhance survival outcomes.

Validity of laparoscopic surgery for lower gastrointestinal perforations.

INTRODUCTION: This study aimed to clarify the validity of laparoscopic surgery for lower gastrointestinal perforation by comparing the clinical outcomes of laparoscopic and open emergency surgery. METHODS: We reviewed the data of patients who underwent surgery for lower gastrointestinal perforation. Patients were categorized into two groups: the laparoscopic group who underwent laparoscopic surgery, and the open group who underwent laparotomy. Clinical and operative outcomes between the two groups were evaluated. RESULTS: A total of 219 patients were included in the study. There were 66 and 153 patients with small bowel and colorectal perforations, respectively. The median operative time in the laparoscopic group was shorter than that in the open group (126 min vs. 146 min, p = .049). The mean amount of intraoperative blood loss was significantly lower in the laparoscopic group (50.4 mL vs. 400.1 mL, p < .001). The incidence of postoperative complication was higher in the open group (20.0% vs. 66.5%, p < .001), especially wound infection (0% vs. 26.3%, p = .002). Median hospital stays were 14 days and 24 days in the laparoscopic and open groups, respectively (p < .001). In the laparoscopic group, hospital mortality was 0%. CONCLUSIONS: The laparoscopic approach for small bowel and colorectal perforation in an emergency setting is a safe procedure in carefully selected patients and may contribute to decreased intraoperative blood loss, shortened hospital stay, and decreased incidence of postoperative complications, especially wound infection.

Proposal of "borderline resectable" colorectal liver metastases based on analysis of risk factors for early surgical failure.

PURPOSE: We aimed to define borderline resectable colorectal liver metastases (CRLM) based on the analysis of risk factors for early surgical failure and investigate the efficacy of neoadjuvant chemotherapy in these patients. METHODS: This was a retrospective analysis of a multi-institutional cohort of patients diagnosed with technically resectable CRLM. Early surgical failure within 6 months of liver surgery was defined as ESF6. We classified CRLM into three grades (A, B, and C) according to the definition of the Japanese Society for Cancer of the Colon and Rectum. RESULTS: Among the 249 patients with technically resectable CRLM, 46 (18.5%) developed ESF6. The survival rate of these patients was significantly lower than that of the patients without ESF6. In the multivariate analysis of synchronous CRLM patients, no neoadjuvant chemotherapy, Grade B/C, and Charlson comorbidity index ≥ 3 were independent predictors of ESF6. Among patients with synchronous and Grade B/C CRLM, ESF6 rates, surgical failure-free survival, and overall survival in the neoadjuvant chemotherapy group were significantly better relative to the upfront surgery group. CONCLUSIONS: Patients with synchronous and Grade B/C CRLM are at a high risk of early surgical failure, have a poor long-term prognosis, and can be defined as borderline resectable and good candidates for neoadjuvant chemotherapy.

Colorectal Cancer Recurrence Prediction Using a Tissue-Free Epigenomic Minimal Residual Disease Assay.

PURPOSE: Post-treatment detection of circulating tumor DNA (ctDNA) is strongly predictive of recurrence. Most molecular residual disease (MRD) assays require prior tissue testing to guide ctDNA analysis, resulting in lengthy time to initial results and unevaluable patients. PATIENTS AND METHODS: We assessed a tissue-free assay (Guardant Reveal) that bioinformatically evaluates >20,000 epigenomic regions for ctDNA detection in 1,977 longitudinally collected post-operative plasma samples from 342 patients with resected colorectal cancer (CRC). RESULTS: We observed sensitive and specific detection of MRD associated with clinically meaningful differences in recurrence-free interval at each timepoint evaluated with a median lead time of 5.3 months. Longitudinal sensitivity in stage II or higher colon cancer was 81%. Sensitivity increased with serial measurement and varied by recurrence site: higher for liver (100%) versus lung (53%) and peritoneal (40%). Sensitivity among rectal cancer patients was 60% owing to a high proportion of lung metastases. Specificity was 98.2% among 1,461 post-treatment samples (99.1% among those with follow-up longer than the upper interquartile range of the lead time observed in this study). CONCLUSIONS: Our data demonstrate the potential clinical utility of ctDNA as a tool to improve management of stage II and higher CRC with a methodology that is non-invasive, accessible, and allows for rapid evaluation to inform clinical decisions.

The SCRUM-MONSTAR Cancer-Omics Ecosystem: Striving for a Quantum Leap in Precision Medicine.

The SCRUM-Japan MONSTAR-SCREEN consortium is a nationwide molecular profiling project employing artificial intelligence-driven multi-omics analyses for patients with advanced malignancies, aiming to develop novel therapeutics and diagnostics and deliver effective drugs to patients. Concurrently, studies assessing molecular residual disease-based precision medicine for resectable solid tumors, including CIRCULATE-Japan, are ongoing. The substantial data generated by these platforms are stored within a state-of-the-art supercomputing infrastructure, VAPOR CONE. Since 2015, our project has registered over 24,000 patients as of December 2023. Among 16,144 patients with advanced solid tumors enrolled in MONSTAR-SCREEN projects, 5.0% participated in matched clinical trials, demonstrating a 29.2% objective response rate and 14.8-month median survival (95% confidence interval, 13.4-16.3), for patients treated in the matched clinical trials. Notably, patients who received matched therapy demonstrated significantly prolonged overall survival compared with those who did not (hazard ratio 0.77; 95% confidence interval, 0.71-0.83).

The anti-tumor effect of trifluridine via induction of aberrant mitosis is unaffected by mutations modulating p53 activity.

The fluorinated thymidine analog trifluridine (FTD) is a chemotherapeutic drug commonly used to treat cancer; however, the mechanism by which FTD induces cytotoxicity is not fully understood. In addition, the effect of gain-of-function (GOF) missense mutations of the TP53 gene (encoding p53), which promote cancer progression and chemotherapeutic drug resistance, on the chemotherapeutic efficacy of FTD is unclear. Here, we revealed the mechanisms by which FTD-induced aberrant mitosis and contributed to cytotoxicity in both p53-null and p53-GOF missense mutant cells. In p53-null mutant cells, FTD-induced DNA double-stranded breaks, single-stranded DNA accumulation, and the associated DNA damage responses during the G2 phase. Nevertheless, FTD-induced DNA damage and the related responses were not sufficient to trigger strict G2/M checkpoint arrest. Thus, these features were carried over into mitosis, resulting in chromosome breaks and bridges, and subsequent cytokinesis failure. Improper mitotic exit eventually led to cell apoptosis, caused by the accumulation of extensive DNA damage and the presence of micronuclei encapsulated in the disrupted nuclear envelope. Upon FTD treatment, the behavior of the p53-GOF-missense mutant, isogenic cell lines, generated by CRISPR/Cas9 genome editing, was similar to that of p53-null mutant cells. Thus, our data suggest that FTD treatment overrode the effect on gene expression induced by p53-GOF mutants and exerted its anti-tumor activity in a manner that was independent of the p53 function.

Importance of duodenal stump reinforcement to prevent stump leakage after gastrectomy: a large-scale multicenter retrospective study (KSCC DELICATE study).

BACKGROUND: The significance of reinforcement of the duodenal stump with seromuscular sutures and the effectiveness of reinforced staplers in preventing duodenal stump leakage remain unclear. We aimed to explore the importance of duodenal stump reinforcement and determine the optimal reinforcement method for preventing duodenal stump leakage. METHODS: This retrospective cohort study was conducted between January 1, 2012 and December 31, 2021, with data analyzed between December 1, 2022 and September 30, 2023. This multicenter study across 57 institutes in Japan included 16,475 patients with gastric cancer who underwent radical gastrectomies. Elective open or minimally invasive (laparoscopic or robotic) gastrectomy was performed in patients with gastric cancer. RESULTS: Duodenal stump leakage occurred in 153 (0.93%) of 16,475 patients. The proportions of males, patients aged ≥ 75 years, and ≥ pN1 were higher in patients with duodenal stump leakage than in those without duodenal stump leakage. The incidence of duodenal stump leakage was significantly lower in the group treated with reinforcement by seromuscular sutures or using reinforced stapler than in the group without reinforcement (0.72% vs. 1.19%, p = 0.002). Duodenal stump leakage incidence was also significantly lower in high-volume institutions than in low-volume institutions (0.70% vs. 1.65%, p = 0.047). The rate of duodenal stump leakage-related mortality was 7.8% (12/153). In the multivariate analysis, preoperative asthma and duodenal invasion were identified as independent preoperative risk factors for duodenal stump leakage-related mortality. CONCLUSIONS: The duodenal stump should be reinforced to prevent duodenal stump leakage after radical gastrectomy in patients with gastric cancer.

Clinical practice guidelines for telesurgery 2022 : Committee for the promotion of remote surgery implementation, Japan Surgical Society.

Telesurgery is expected to improve medical access in areas with limited resources, facilitate the rapid dissemination of new surgical procedures, and advance surgical education. While previously hindered by communication delays and costs, recent advancements in information technology and the emergence of new surgical robots have created an environment conducive to societal implementation. In Japan, the legal framework established in 2019 allows for remote surgical support under the supervision of an actual surgeon. The Japan Surgical Society led a collaborative effort, involving various stakeholders, to conduct social verification experiments using telesurgery, resulting in the development of a Japanese version of the "Telesurgery Guidelines" in June 2022. These guidelines outline requirements for medical teams, communication environments, robotic systems, and security measures for communication lines, as well as responsibility allocation, cost burden, and the handling of adverse events during telesurgery. In addition, they address telementoring and full telesurgery. The guidelines are expected to be revised as needed, based on the utilization of telesurgery, advancements in surgical robots, and improvements in information technology.

QUATTRO-II randomized trial: CAPOXIRI+bevacizumab vs. FOLFOXIRI+bevacizumab as first-line treatment in patients with mCRC.

BACKGROUND: The QUATTRO-II trial examined the efficacy and safety of capecitabine+oxaliplatin+irinotecan (CAPOXIRI)+bevacizumab (BEV) vs. 5-fluorouracil+folinic acid+oxaliplatin+irinotecan (FOLFOXIRI)+BEV in metastatic colorectal cancer (mCRC). METHODS: In this phase II study (ClinicalTrials.gov: NCT04097444; jRCTs041190072), patients were randomized (1:1) to FOLFOXIRI+BEV or CAPOXIRI+BEV. The induction treatment in the FOLFOXIRI+BEV/CAPOXIRI+BEV arms was continued for 8/6 cycles (maximum 12/8 cycles if feasible), and the maintenance treatment was 5-fluorouracil/leucovorin+BEV or capecitabine+BEV at the investigators' discretion. The primary endpoint was progression-free survival (PFS), with the two arms deemed equivalent if the hazard ratio (HR) of the point estimate was 0.80 < HR < 1.25. Secondary endpoints were overall response rate (ORR), overall survival (OS), incidence of adverse events (AEs), and patient-reported outcomes. FINDINGS: Overall, 51 and 52 patients were randomized to FOLFOXIRI+BEV and CAPOXIRI+BEV, respectively. The study met its primary endpoint; PFS at median follow-up of 23.7 months was 10.6 months (95% confidence interval [CI], 7.7-13.3) in the FOLFOXIRI+BEV arm vs. 10.9 months (95% CI, 9.3-14.3) in the CAPOXIRI+BEV arm (HR 1.114 [0.80 < HR < 1.25], p = 0.654). In the FOLFOXIRI+BEV vs. CAPOXIRI+BEV arms, the 2-year OS rate (95% CI) was 65.5% (49.5%-77.6%) vs. 74.3% (59.8%-84.2%), and the ORR (95% CI) was 76.5% (62.5%-87.2%) vs. 84.6% (71.9%-93.1%). Major (grade ≥3) AEs in the FOLFOXIRI+BEV vs. CAPOXIRI+BEV arms were neutropenia (68.6% vs. 40.4%), febrile neutropenia (9.8% vs. 11.5%), diarrhea (7.8% vs. 17.3%), and appetite loss (7.8% vs. 17.3%). CONCLUSION: CAPOXIRI+BEV was well tolerated with reduced hematological toxicity and efficacy comparable to those of FOLFOXIRI+BEV, providing a potentially convenient first-line treatment alternative to FOLFOXIRI+BEV in patients with mCRC. FUNDING: Chugai Pharmaceutical Co., Ltd.

Association Between Preoperative Osteopenia and Prognosis in Breast Cancer Patients.

BACKGROUND/AIM: Osteopenia, the loss of bone mineral density (BMD), was recently reported as a prognostic factor in various cancers. However, the prognostic significance of preoperative osteopenia in breast cancer remains unclear. This study aimed to clarify the clinical significance of preoperative osteopenia in breast cancer. PATIENTS AND METHODS: We retrospectively analyzed the relationship between osteopenia and clinical factors and prognosis in 532 patients with pathological Stage I-III primary breast cancer between 2009 and 2017. Osteopenia was assessed by measuring the average pixel density (Hounsfield unit) in the midvertebral core of the 11th thoracic vertebra on enhanced preoperative computed tomography. RESULTS: Osteopenia was diagnosed in 186 (35.0%) patients. The recurrence-free survival (RFS) rate was significantly worse in the osteopenia group than in the non-osteopenia group (p=0.0275), but there was no significant difference in overall survival (OS) between the two groups. When evaluated by menopausal status, RFS and OS were significantly worse in the osteopenia group than in the non-osteopenia group (p=0.0094 and p=0.0264, respectively) in premenopausal patients. However, there were no significant differences in RFS and OS between the two groups among postmenopausal patients. In premenopausal patients, osteopenia was an independent prognostic factor for RFS in a multivariate analysis (p=0.0266). CONCLUSION: Preoperative osteopenia was independently associated with recurrence of breast cancer.

Evaluation of gastric tube blood flow by multispectral camera and fluorescence angiography.

Background: Evidence regarding the application of the multispectral camera for blood flow measurement is insufficient, and its performance has not been compared with the conventional indocyanine green (ICG) method. Therefore, we retrospectively compared the effectiveness of a new multispectral camera for non-invasive, real-time, quantitative imaging of tissue oxygen (O2) saturation and hemoglobin (Hb) levels and commercially available ICG fluorescence imaging in hemodynamic assessment of gastric tubes in esophagectomy. Methods: Thirty patients who underwent thoracoscopic esophagectomy and gastric tube reconstruction for esophageal cancer were included in this study. The multispectral camera was used to measure tissue O2 saturation and Hb levels. The ICG fluorescence imaging, with the analysis software tool Lumi view, was employed to record ICG luminance changes, with values measured at the anastomotic site. Furthermore, the usefulness of each assessment device was examined using the arterial and venous blood flow indices as cutoff lines for cases with anastomotic failure. Results: In the evaluation of arterial perfusion, anastomotic leak occurred in three of the five (60 %) patients with arterial insufficiency as assessed by the ICG imaging, while anastomotic leakage occurred in all three patients (100 %) who were assessed as having arterial insufficiency by the multispectral camera. In the evaluation of venous perfusion, anastomotic leakage occurred in three of the nine (33.3 %) patients diagnosed with venous stasis by the IC imaging and in three of the five (60 %) patients assessed by the multispectral camera. Conclusion: The multispectral camera assessed gastric tube blood flow more accurately than the ICG fluorescence method.

Impact of surgical proximal and distal margins on the recurrence of resectable colon cancer: a single-center observational cohort study.

PURPOSE: Few studies have investigated the impact of the surgical proximal and distal margins on colon cancer recurrence. We conducted this study to investigate the effect of resection margins on the prognosis of resectable colon cancer. METHODS: We analyzed data on 1458 patients who underwent colorectal resection in our institute between January, 2004 and March, 2020, including 579 patients with resectable colon cancer. The association between the resection margin and recurrence for each oncological status was assessed and the value of the resection length that influenced recurrence was analyzed. RESULTS: Patients who had pT4 colon cancer with margins of more than 7 cm had a trend of fewer recurrences and longer relapse-free survival (RFS) than those with colon cancer of other stages (P = 0.033; hazard ratio [HR], 0.42; 95% confidence interval [CI], 0.20-0.89). Multivariate analysis identified a margin of < 7 cm as an independent risk factor for RFS in patients with pT4 colon cancer (P = 0.023; HR, 2.65; 95% CI 1.013-6.17). No correlation was found between resection margins and recurrence, depending on the extent of lymph node metastasis and tumor location. CONCLUSION: A resection margin of at least 7 cm should be maintained for patients with pT4 colon cancer.

A Multicenter Analysis of Short-term and Long-term Outcomes Following Laparoscopic Multivisceral Resection for Advanced Colorectal Cancer.

Background/Aim: Recent research has demonstrated that laparoscopic multivisceral resection (MVR) for advanced colorectal cancer is safe, practicable, and yields satisfactory oncological results, which is in line with the growing usage of laparoscopic surgery. The effectiveness of laparoscopic MVR is still debatable, though. The goal of this study was to compare the short- and long-term results of patients with advanced colorectal cancer treated with open MVR with laparoscopic procedures. Patients and Methods: Data on 3,571 consecutive patients hospitalized at the Kyushu University National Kyushu Cancer Center for colorectal cancer surgery between 2004 and 2020 were gathered retrospectively. In the end, 84 individuals with advanced colorectal cancer who had a colectomy with MVR were examined. We evaluated invasiveness in terms of complications, blood loss, and operating time. Recurrence-free survival rates and overall 5-year survival were among the oncological outcomes. Results: Of the 84 patients examined, 29 underwent laparoscopic treatment, and 55 underwent open treatment. The laparoscopic surgery group experienced shorter hospital stays (15 vs. 18 days, p<0.05) and much less blood loss (median volume: 167 vs. 1,058 g, p<0.005) than the open surgery group. Following the exclusion of patients with stage IV colorectal cancer from the study (groups undergoing laparoscopic surgery, n=25; open surgery, n=38), the groups displayed comparable pathologic results and no discernible variations in either the 5-year overall survival (p=0.87) or recurrence-free survival (p=0.86). Conclusion: In certain individuals with advanced colorectal cancer, a laparoscopic method of manipulation with MVR may be less invasive than an open method without compromising the prognosis.

Tele-proctoring for minimally invasive surgery across Japan: An initial step toward a new approach to improving the disparity of surgical care and supporting surgical education.

Aim: The aim of this study was to verify the clinical feasibility of tele-proctoring using our ultra-low latency communication system with shared internet access. Methods: Connections between two multiple remote locations at various distances were established through the TELEPRO® tele-proctoring system. The server records the latency between the two locations for tele-proctoring using the annotations. Questionnaires were administered to the surgeons, assistants, and medical staff. Respondents rated the quickness and quality of communication in terms of latency and disturbances in the audio, video, and usefulness of the live telestrations with annotation. Results: Seven hospitals tele-proctored with Sapporo Medical University between January 2021 and September 2022. The median latency of annotation between the two locations ranged from 24.5 to 48.5 ms. No major technological problems occurred, such as streaming interruption, loss of video or audio, poor resolution. The video encoding time was 10 ms, and its decoding time was 0.8 ms. The total latency positively correlated with the distance between two locations (R = 0.55, p < 0.01). The quality of communication regarding latency, disturbance, and surgical education with intraoperative annotative instructions showed similar trends, with perfectly fine being the most common response. No significant differences in surgical quality, educational effect, or social impact were observed between the latency ≥30 and <30 ms groups for whether the size of latency affects surgical education. Conclusion: The feasibility of the tele-proctoring system is expected to be a sustainable approach to help education for young surgeons and surgical supports in rural areas, thereby reducing disparities in health care.

Immune checkpoint status and oncogenic mutation profiling of rectal cancer after neoadjuvant chemotherapy (KSCC1301-A2).

Aim: Immune checkpoint inhibitors (ICIs) are less effective in mismatch repair (MMR)-proficient (pMMR) colorectal cancers (CRCs) than in MMR-deficient CRCs. Here, we investigated changes in the tumor microenvironment after neoadjuvant chemotherapy (NAC) without radiotherapy in locally advanced rectal cancer (LARC) and the potential of ICIs as therapeutic agents for pMMR CRCs. Methods: This was an ad hoc analysis of a KSCC1301 randomized phase II trial in which patients with untreated resectable LARC were randomly assigned to receive S-1 and oxaliplatin or folinic acid, 5-fluorouracil, and oxaliplatin as NAC. Forty-nine patients were studied in this ad hoc analysis. As a reference cohort, we assessed 25 rectal cancer patients who underwent surgery without NAC outside the randomized trial. Immune checkpoint molecules (ICMs; PD-1, PD-L1, CTLA-4, LAG3), tumor-infiltrating lymphocytes (TILs; CD8, FOXP3), and other related proteins were evaluated by immunohistochemistry. Next-generation sequencing (NGS) using Oncomine™ Comprehensive Assay version 3 was conducted in 23 patients. Results: The expression levels of PD-1, CTLA-4, and LAG3 in the NAC group were significantly higher than in reference patients (p < 0.001). Additionally, the infiltration of CD8+ and FOXP3+ T cells, and the CD8/FOXP3 ratio were significantly higher in the NAC group than in reference patients (p < 0.0001). NGS analysis revealed no specific gene alteration related to TILs or ICMs. Conclusion: We demonstrated changes in the tumor immune microenvironment after NAC in pMMR rectal cancer. NAC was associated with increased expression of ICMs and TILs. Rectal cancer could be susceptible to combined immunotherapy with chemotherapy.

Oxaliplatin-Based Adjuvant Chemotherapy in Older Patients With Stage III Colon Cancer: An ACCENT/IDEA Pooled Analysis of 12 Trials.

PURPOSE: A number of studies suggest that older patients may have reduced or no benefit from the addition of oxaliplatin to fluoropyrimidines as adjuvant chemotherapy for stage III colon cancer (CC). MATERIALS AND METHODS: We studied the prognostic impact of age, as well as treatment adherence/toxicity patterns according to age, in patients with stage III CC who received 3 or 6 months of infusional fluorouracil, leucovorin, and oxaliplatin/capecitabine and oxaliplatin (CAPOX) on the basis of data collected from trials from the ACCENT and IDEA databases. Associations between age and time to recurrence (TTR), disease-free survival (DFS), overall survival (OS), survival after recurrence (SAR), and cancer-specific survival (CSS) were assessed by a Cox model or a competing risk model, stratified by studies and adjusted for sex, performance status, T and N stage, and year of enrollment. RESULTS: A total of 17,909 patients were included; 24% of patients were age older than 70 years (n = 4,340). Patients age ≥70 years had higher rates of early treatment discontinuation. Rates of grade ≥3 adverse events were similar between those older and younger than 70 years, except for diarrhea and neutropenia that were more frequent in older patients treated with CAPOX (14.2% v 11.2%; P = .01 and 12.1% v 9.6%; P = .04, respectively). In multivariable analysis, TTR was not significantly different between patients <70 years and those ≥70 years, but DFS, OS, SAR, and CSS were significantly shorter in those patients ≥70 years. CONCLUSION: In patients ≥70 years with stage III CC fit enough to be enrolled in clinical trials, oxaliplatin-based adjuvant chemotherapy was well tolerated and led to similar TTR compared with younger patients, suggesting similar efficacy. TTR may be a more appropriate end point for efficacy in this patient population.

Transitional dynamics in oncology clinical trials: evaluating the impact of Clinical Trials Act on cooperative groups.

OBJECTIVE: large-scale multicentre clinical trials conducted by cooperative groups have generated a lot of evidence to establish better standard treatments. The Clinical Trials Act was enforced on 1 April 2018, in Japan, and it has remarkably increased the operational burden on investigators, but its long-term impact on cancer cooperative groups is unknown. METHODS: a survey was conducted across the nine major cooperative groups that constitute the Japan Cancer Trials Network to assess the impact of Clinical Trials Act on the number of newly initiated trials from fiscal year (from 1 April to 31 March) 2017 to 2022 and that of ongoing trials on 1 April in each year from 2018 to 2023. RESULTS: the number of newly initiated trials dropped from 38 trials in fiscal year 2017 to 26 trials in fiscal year 2018, surged to 50 trials in fiscal year 2019, but then gradually decreased to 25 trials by fiscal year 2022. Specified clinical trials decreased from 32 trials in fiscal year 2019 to 12 trials in fiscal year 2022. The number of ongoing trials was 220 trials in 2018, peaked at 245 trials in 2020, but then gradually decreased to 219 trials by 2023. The number of specified clinical trials has been in consistent decline. By April 2023, of the 20 ongoing non-specified clinical trials, nine adhered to Clinical Trials Act and 11 followed the Ethical Guidelines for Medical and Health Research Involving Human Subjects. CONCLUSION: the number of multicentre clinical trials in oncology gradually decreased after the Clinical Trials Act's enforcement, which underscores the need for comprehensive amendment of the Clinical Trials Act to streamline the operational process.

Clinicopathological significance of microsatellite instability and immune escape mechanism in patients with gastric solid-type poorly differentiated adenocarcinoma.

BACKGROUND: In gastric solid-type poorly differentiated adenocarcinoma (PDA), the role of microsatellite instability and immune escape mechanism remains unclear. The current study aimed to elucidate the clinical significance of mismatch repair (MMR) status, genome profile, C-X-C motif chemokine receptor 2 (CXCR2) expression, and myeloid-derived suppressor cell (MDSC) infiltration in solid-type PDA. METHODS: In total, 102 primary solid-type PDA cases were retrieved, and classified into 46 deficient-MMR (dMMR) and 56 proficient-MMR (pMMR) cases based on immunohistochemistry (IHC) and polymerase chain reaction-based molecular testing results. The mRNA expression profiles (NanoString nCounter Assay) of stage-matched dMMR (n = 6) and pMMR (n = 6) cases were examined. The CXCR2 expression and MDSC infiltration (CD11b- and CD33-positive cells) were investigated via IHC in all solid-type PDA cases. RESULTS: mRNA analysis revealed several differentially expressed genes and differences in biological behavior between the dMMR (n = 46) and pMMR (n = 56) groups. In the multivariate analysis, the dMMR status was significantly associated with a longer disease-free survival (hazard ratio = 5.152, p = 0.002) and overall survival (OS) (hazard ratio = 5.050, p = 0.005). CXCR2-high expression was significantly correlated with a shorter OS in the dMMR group (p = 0.018). A high infiltration of CD11b- and CD33-positive cells was significantly correlated with a shorter OS in the pMMR group (p = 0.022, 0.016, respectively). CONCLUSIONS: dMMR status can be a useful prognostic predictor, and CXCR2 and MDSCs can be novel therapeutic targets in patients with solid-type PDA.