論文

Purpose: To demonstrate the negative prognostic impact of a panel of genomic alterations (PRESSING-HER2 panel) and lack of HER2 amplification by next-generation sequencing (NGS) in patients with HER2þ, RAS wild-type metastatic colorectal cancer receiving dual HER2 blockade. Experimental Design: The PRESSING-HER2 panel of HER2 mutations/rearrangements and RTK/MAPK mutations/amplifications was assessed by NGS. HER2 amplification was confirmed by NGS if copy-number variation (CNV) was ≥ 6. With a case–control design, hypothesizing 30% and 5% PRESSING-HER2 positivity in resistant [progression-free survival (PFS) <4 months and no RECIST response] versus sensitive cohorts, respectively, 35 patients were needed per group. Results: PRESSING-HER2 alterations included HER2 mutations/ rearrangements, EGFR amplification, and BRAF mutations and had a prevalence of 27% (9/33) and 3% (1/35) in resistant versus sensitive patients (P ¼ 0.005) and 63% predictive accuracy. Overall, HER2 nonamplified status by NGS had 10% prevalence. Median PFS and overall survival (OS) were worse in PRESSING-HER2þ versus negative (2.2 vs. 5.3 months, P < 0.001; 5.4 vs. 14.9 months, P ¼ 0.001) and in HER2 nonamplified versus amplified (1.6 vs. 5.2 months, P < 0.001; 7.4 vs. 12.4 months, P ¼ 0.157). These results were confirmed in multivariable analyses [PRESSING-HER2 positivity: PFS HR ¼ 3.06, 95% confidence interval (CI), 1.40–6.69, P ¼ 0.005; OS HR ¼ 2.93, 95% CI, 1.32–6.48, P ¼ 0.007]. Combining PRESSING-HER2 and HER2 CNV increased the predictive accuracy to 75%. Conclusions: PRESSING-HER2 panel and HER2 nonamplified status by NGS warrant validation as potential predictive markers in this setting.

Background: Neoadjuvant radiotherapy and chemotherapy followed by surgical resection is a standard treatment for LARC. As anti-PD-1 therapy for patients with dMMR colorectal cancer is responsive in the context of metastatic disease, several clinical trials which evaluate the efficacies of anti-PD-1 therapy in patients with dMMR LARC are on-going and suggested the outstanding responses (Cercek A. et al., N Engl J Med 2022). Methods: We initiated the EPOC 2201 VOLTAGE-2 study, which is an ongoing, non-randomized, single-arm phase II trial. The major eligibility criteria were as follows: treatment-naïve with rectal cancer located 12 cm from the anal verge; confirmed dMMR; clinical stage II/III in primary cohort (N=35) and stage I in exploratory cohort (N=20); age ≥ 18; Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1; and presence of sufficient organ function. The study treatments include 12 cycles of nivolumab (NIVO) monotherapy (240 mg every 2 weeks) followed by assessment using Memorial Sloan Kettering (MSKCC) Regression Schema (Smith J.J. et al., BMC Cancer 2015). If clinical complete response (cCR) or near complete response (nCR) are observed, non-operative management with additional 12 cycles of NIVO will be performed. If incomplete response (IR) is observed, standard chemoradiotherapy with 50.4Gy of radiation plus capecitabine followed by surgery will be performed. The primary endpoint is the 2-year cCR rate in primary cohort. Various survival endpoints including progression-free survival (PFS) and overall survival (OS) are assessed as secondary endpoints. Safety analyses are performed using the Common Terminology Criteria for Adverse Events (CTCAE) ver. 5.0, and the Clavien‒Dindo classification (ver. 2.0) is added for postoperative complications. Assuming null and alternative hypotheses, cCR rates of 23% and 45%, the planned sample size for primary cohort was set at 35, with a one-sided alpha of 5% and power of 80%. An exploratory biomarker study was also conducted using serially collected tumor and blood samples. Whole genome-based minimal residual disease (MRD) assay and whole exome/whole transcriptome-based tumor and immune microenvironment analyses are performed. As of August 2023, patient’s enrollment is ongoing. Clinical trial information: jRCT2031220484.

3519 Background: Chemoradiotherapy and total neoadjuvant therapy are the standard treatments for locally advanced rectal cancer (LARC). Although radiotherapy (RT) is an integral part of treatment, it negatively impacts anal function after TME for cases of very low-lying LARCs. This trial examined the efficacy, safety, and influence on postoperative anal function of NAC without RT in patients (pts) with very low-lying cT3 LARCs. Methods: Pts with cT3N0-2M0 adenocarcinomas located within 5 cm from the anal verge, whose anuses were expected to be preserved, were randomly assigned (1:1) to either the NAC group (preoperative chemotherapy with six cycles of mFOLFOX6 or four cycles of CAPOX followed by TME; then, postoperative identical regimen) or the TME group (upfront TME followed by postoperative chemotherapy with 12 cycles of mFOLFOX6 or 8 cycles of CAPOX), stratified by cN stage, center, and sex. The primary endpoint was the 3-year recurrence-free survival (RFS), which was compared between groups using a stratified log-rank test at a one-sided alpha level of 20%. Results: Between February 2013 and March 2019, 130 pts were enrolled and randomly assigned to a treatment group. A total of 127 pts were evaluable (65 in the NAC group and 62 in the TME group). All but one patient with early progression completed preoperative chemotherapy in the NAC group, and all pts in both groups underwent TME. After a median follow-up of 37.4 months (IQR 36.5-40.5), the 3-year RFS was 75.5% (95% CI 62.5-84.5) in the NAC group vs. 70.9% (95%CI 57.2-80.9) in the TME group (hazard ratio 0.67, 95% CI 0.34-1.32; P = 0.098), and the primary endpoint was met. There were no differences in the occurrence of grade 3 or higher postoperative complications (20% in the NAC group vs. 21% in the TME group [P = 1.000]), chemo-associated grade 3 or higher adverse events (28% in the NAC group vs. 23% in the TME group [P = 0.551]), or any grade of peripheral sensory neuropathy lasting for 3 years (22.7% in the NAC group vs. 38.5% in the TME group in pts treated with mFOLFOX6 [P = 0.3163], 7.1% in the NAC group vs. 33.3% in the TME group in pts treated with CAPOX [P = 0.1038]), between the groups. No treatment-related deaths occurred in either of the groups. At 3 years after randomization, 61 pts in the NAC group (93.8%) and 52 pts in the TME group (83.9%) could defecate via their anuses (P = 0.092). The median Wexner incontinence score was 11.0 in the NAC group and 10.0 in the TME group (P = 0.3405). Conclusions: For pts with very low-lying cT3 LARC, NAC followed by TME and adjuvant chemotherapy achieved significantly better RFS and anus-preserving rates compared to upfront TME followed by adjuvant chemotherapy, without deteriorating postoperative complications or postoperative anal function. Clinical trial information: UMIN000009510 .

OBJECTIVE: To determine whether neoadjuvant chemotherapy (NAC) followed by total mesorectal excision (TME) and adjuvant chemotherapy (AC) is superior to TME followed by AC for very low-lying clinical (c) T3 rectal cancer. BACKGROUND: Preoperative radiation is widely used for preoperative treatment of cT3 rectal cancer; however, it worsens patient-reported outcomes (PROs). Preoperative treatment without radiation is expected to preserve PROs. METHODS: Patients with cT3N-anyM0 rectal cancer located within 5 cm from the anal verge were randomly assigned (1:1) to the NAC group (3 months of NAC followed by TME and 3 months of AC) or AC group (TME followed by 6 months of AC). NAC and AC comprised mFOLFOX6 (oxaliplatin, l-folinic acid, and fluorouracil) or CAPOX (oxaliplatin and capecitabine). The primary endpoint was the 3-year recurrence-free survival (RFS). PROs were analyzed. RESULTS: Between February 2013 and March 2019, 130 patients were randomly assigned to the NAC (n = 65) or AC (n = 65) groups; of these, 127 were evaluable (NAC, n = 65; AC, n = 62). At a median follow-up of 37.4 months, the 3-year RFS was 75.5% and 70.9% in NAC and AC groups, respectively [hazard ratio (HR) = 0.67, 60% confidence interval (CI) = 0.48-0.86, 95% CI = 0.34-1.32; P = 0.098 by log-rank test] and the primary endpoint was met. There was no significant intergroup difference in the local recurrence rate (LRR) or overall survival. Histologically, good responders to NAC showed a trend toward better RFS than poor responders. The study groups showed similar PROs. CONCLUSIONS: NAC for very low-lying cT3 rectal cancer improved RFS without worsening PROs although LRR remained high. TRIAL REGISTRATION: UMIN Clinical Trials Registry: UMIN000009510/Japan Registry of Clinical Trials: jRCTs031180278.

Constructing precise micro-nano metal patterns on complex three-dimensional (3D) plastic parts allows the fabrication of functional devices for advanced applications. However, this patterning is currently expensive and requires complex processes with long manufacturing lead time. The present work demonstrates a process for the fabrication of micro-nano 3D metal-plastic composite structures with arbitrarily complex shapes. In this approach, a light-cured resin is modified to prepare an active precursor capable of allowing subsequent electroless plating (ELP). A multi-material digital light processing 3D printer was newly developed to enable the fabrication of parts containing regions made of either standard resin or active precursor resin nested within each other. Selective 3D ELP processing of such parts provided various metal-plastic composite parts having complicated hollow micro-nano structures with specific topological relationships on a size scale as small as 40 um. Using this technique, 3D metal topologies that cannot be manufactured by traditional methods are possible, and metal patterns can be produced inside plastic parts as a means of further miniaturizing electronic devices. The proposed method can also generate metal coatings exhibiting improved adhesion of metal to plastic substrate. Based on this technique, several sensors composed of different functional nonmetallic materials and specific metal patterns were designed and fabricated. The present results demonstrate the viability of the proposed method and suggest potential applications in the fields of smart 3D micro-nano electronics, 3D wearable devices, micro/nano-sensors, and health care.

Background: The optimal treatment strategy for resectable BRAF V600E mutant colorectal oligometastases (CRM) has not been established due to the rarity and rapid progression of the disease. Since the unresectable recurrence rate is high, development of novel perioperative therapies are warranted. On December 2020, the BEACON CRC triplet regimen of encorafenib, binimetinib, and cetuximab was approved for unresectable metastatic colorectal cancer in Japan. Methods: The NEXUS trial is a multicenter phase II clinical study evaluating the efficacy and safety of the perioperative use of encorafenib, binimetinib, and cetuximab in patients with previously untreated surgically resectable BRAF V600E mutant CRM. The key inclusion criteria are as follows: histologically diagnosed with colorectal adeno/adenosquamous carcinoma; RAS wild-type and BRAF V600E mutation by tissue or blood; and previously untreated resectable distant metastases. The triplet regimen (encorafenib: 300 mg daily; binimetinib: 45 mg twice daily; cetuximab: 400 mg/m2, then 250 mg/m2 weekly, 28 days/cycle) is administered for 3 cycles each before and after curative resection. The primary endpoint of the study is the 1-year progression-free survival (PFS) rate and the secondary end points are the PFS, disease-free survival, overall survival, and objective response rate. The sample size is 32 patients. Endpoints in the NEXUS trial as well as integrated analysis with the nationwide registry data will be considered for seeking regulatory approval for the perioperative use of the triplet regimen. Discussion: The use of the triplet regimen in the perioperative period is expected to be safe and effective in patients with resectable BRAF V600E mutant CRM. Trial registration: jRCT2031220025, April. 16, 2022.

3503Background: NIVO + IPI demonstrated superior progression-free survival (PFS) vs chemo in patients (pts) with previously untreated MSI-H/dMMR mCRC in the randomized phase 3 CheckMate 8HW study (NCT04008030). We report expanded efficacy analysis from the prespecified interim analysis of NIVO + IPI vs chemo in the 1L setting. Methods: Pts with unresectable or mCRC and MSI-H/dMMR status by local testing were enrolled across different lines of therapy and randomized 2:2:1 to NIVO (240 mg) + IPI (1 mg/kg) Q3W (4 doses, then NIVO 480 mg Q4W), NIVO (240 mg) Q2W (6 doses, then NIVO 480 mg Q4W), or chemo ± targeted therapies; treatments continued until disease progression or unacceptable toxicity (all arms) or for up to 2 years (NIVO ± IPI arms). In pts with blinded independent central review (BICR)–documented progression with chemo, crossover to NIVO + IPI was permitted. Dual primary endpoints were PFS by BICR per RECIST v1.1 for NIVO + IPI vs chemo (1L) and NIVO + IPI vs NIVO (all lines) in pts with centrally confirmed MSI-H/dMMR mCRC. PFS2 (time from randomization to progression after subsequent systemic therapy, initiation of second subsequent systemic therapy, or death) was a key exploratory endpoint. Results: Among 303 pts randomized to NIVO + IPI (n = 202) or chemo (n = 101), 171 pts in the NIVO + IPI arm and 84 pts in the chemo arm had centrally confirmed MSI-H/dMMR. At 31.5-months (mo) median follow-up (range 6.1–48.4), NIVO + IPI demonstrated superior PFS vs chemo (HR 0.21; 97.91% CI 0.13–0.35; P < 0.0001). Subsequent systemic therapy was received by 20 (12%) and 57 (68%) pts in the NIVO + IPI and chemo arms, respectively. In the chemo arm, 56 (67%) pts received subsequent immunotherapy (39 [46%] crossed over to NIVO + IPI on study; 17 [20%] received non-study immunotherapy). Median PFS2 was not reached (NR) with NIVO + IPI and 29.9 mo with chemo (HR 0.27; 95% CI 0.17–0.44; Table). Any grade and grade 3/4 treatment-related adverse events (TRAEs) are presented (Table). Treatment-related deaths were reported for 2 pts in the NIVO + IPI arm. Conclusions: Clinical benefit with 1L NIVO + IPI vs chemo was maintained after subsequent therapy, as shown by improved PFS2 in pts with centrally confirmed MSI-H/dMMR mCRC. No new safety concerns were identified with NIVO + IPI. These results further support NIVO + IPI as a standard-of-care 1L treatment option for pts with MSI-H/dMMR mCRC. Clinical trial information: NCT04008030. [Table Presented]

Background: Patients (pts) with MSI-H/dMMR mCRC have poor outcomes with standard chemo ± targeted therapies. NIVO ± IPI are approved in previously treated pts with MSI-H/dMMR mCRC in many countries, based on the phase 2 CheckMate 142 study. CheckMate 8HW (NCT04008030) is a randomized phase 3 study comparing NIVO + IPI with NIVO or chemo in pts with MSI-H/dMMR mCRC. We report progression-free survival (PFS) by blinded independent central review (BICR) at a prespecified interim analysis for NIVO + IPI vs chemo in the 1L setting. Methods: Pts ≥ 18 years with recurrent or mCRC not amenable to surgery and MSI-H/dMMR status per local testing were enrolled across different lines of therapy. Previously untreated pts were randomized 2:2:1 to NIVO (240 mg) + IPI (1 mg/kg) Q3W (4 doses, then NIVO 480 mg Q4W), NIVO (240 mg) Q2W (6 doses, then NIVO 480 mg Q4W), or chemo ± targeted therapies; treatments continued until disease progression or unacceptable toxicity (all arms), or a maximum of 2 years (NIVO ± IPI arms). For pts with BICR-documented progression with chemo, optional crossover to NIVO + IPI was permitted. Dual primary endpoints were PFS by BICR per RECIST v1.1 for NIVO + IPI vs chemo (1L) and NIVO + IPI vs NIVO (all lines) in pts with centrally confirmed MSI-H/dMMR mCRC. Results: In the 1L setting, 303 pts were randomized to NIVO + IPI (n = 202) or chemo (n = 101); of these pts, 171 pts in the NIVO + IPI arm and 84 pts in the chemo arm had centrally confirmed MSI-H/dMMR result by either immunohistochemistry and/or polymerase chain reaction-based tests. With 24.3 months of median follow-up, NIVO + IPI demonstrated clinically meaningful and statistically significant improvement in PFS vs chemo, with a 79% reduction in the risk of disease progression or death (HR 0.21 [95% CI 0.14–0.32]; P < 0.0001) (Table). No new safety signals were identified (Table). Conclusions: NIVO + IPI demonstrated superior PFS vs chemo in previously untreated pts with MSI-H/dMMR mCRC. NIVO + IPI had a different safety profile compared to chemo, with fewer grade 3–4 treatment-related adverse events (TRAEs). These results support 1L NIVO + IPI as a standard-of-care option for pts with MSI-H/dMMR mCRC.

Background: TMB is a biomarker for immune checkpoint inhibitors (ICIs). Analysis of circulating tumor DNA (ctDNA) has the potential to non-invasively identify pts likely to benefit from ICIs by assessing pTMB. We conducted a phase II basket trial as part of the SCRUM-Japan GOZILA umbrella/basket trial to evaluate the efficacy and safety of nivolumab monotherapy in pts with advanced GI cancers with high pTMB. Methods: Eligibility criteria included histologically confirmed unresectable or recurrent GI cancers; ECOG PS of 0 or 1; refractory or intolerant to the standard therapies; and high pTMB identified by Guardant360 CDx, a 74-gene ctDNA assay. Pts received intravenous nivolumab monotherapy of 360 mg every 3 weeks until progressive disease. The primary endpoint was objective response rate (ORR) per investigator assessment. The pTMB score was calculated by adjustment of mutation count by tumor fraction, and initial pTMB thresholds were determined based on previously reported ORR for ICI treatment for each GI cancer in the cohort. The cohort 2 proceeded only for esophageal cancer, and an ultra-high TMB cohort was created to include pts in the top 2% for pTMB scores. Results: Fifty-one pts with high pTMB in the cohort 1/2 (n=32) and the ultra-high TMB cohort (n=19) were enrolled. The median duration of follow-up was 7.5 months (range, 0.9–51.3). Deficient mismatch repair (dMMR) or high microsatellite instability (MSI-H) was observed in 1 pt in cohort 1/2 and 2 in ultra-high TMB cohort. The ORR was 12.5% and 21.1%, with median duration of response of 14.0 months and not reached, respectively. In an exploratory analysis of the overall population, pts with esophageal cancer had the highest ORR of 33.3% (4/12), followed by pancreatic (1/6, 16.7%) and colorectal cancer (3/27, 11.1%). Of 2 pts with proficient MMR/non-MSI-H colorectal cancer who had a response, 1 had a POLE mutation. Pts with response tended to have higher pTMB score (median, 26 vs. 8). dMMR/MSI-H (HR=0.16; 95% CI, 0.02–1.18), PD-L1 CPS $1 (HR=0.55; 95% CI, 0.29–1.01), and absence of liver metastasis (HR=0.36; 95% CI, 1.48–5.14) were significantly associated with longer progression-free survival. Treatment-related grade 3–4 adverse events occurred in 3 pts (9%) in the cohort 1/2 and 3 (16%) in the ultra-high TMB cohort, with no treatment death in either cohort. Conclusions: Nivolumab demonstrated antitumor activity in pretreated pts with advanced GI cancer and high pTMB. These results suggest that the use of pTMB potentially identify patients who may benefit from ICI treatment. Clinical trial information: UMIN000033182. Research Sponsor: None.

Background Patients with microsatellite-instability-high (MSI-H) or mismatch-repair-deficient (dMMR) metastatic colorectal cancer have poor outcomes with standard chemotherapy with or without targeted therapies. Nivolumab plus ipilimumab has shown clinical benefit in nonrandomized studies of MSI-H or dMMR metastatic colorectal cancer. Methods In this phase 3 open-label trial, we randomly assigned patients with unresectable or metastatic colorectal cancer and MSI-H or dMMR status according to local testing to receive, in a 2:2:1 ratio, nivolumab plus ipilimumab, nivolumab alone, or chemotherapy with or without targeted therapies. The dual primary end points, assessed in patients with centrally confirmed MSI-H or dMMR status, were progression-free survival with nivolumab plus ipilimumab as compared with chemotherapy as first-line therapy and progression-free survival with nivolumab plus ipilimumab as compared with nivolumab alone in patients regardless of previous systemic treatment for metastatic disease. At this prespecified interim analysis, the first primary end point (involving nivolumab plus ipilimumab vs. chemotherapy) was assessed. Results A total of 303 patients who had not previously received systemic treatment for metastatic disease were randomly assigned to receive nivolumab plus ipilimumab or chemotherapy; 255 patients had centrally confirmed MSI-H or dMMR tumors. At a median follow-up of 31.5 months (range, 6.1 to 48.4), progression-free survival outcomes (the primary analysis) were significantly better with nivolumab plus ipilimumab than with chemotherapy (P<0.001 for the between-group difference in progression-free survival, calculated with the use of a two-sided stratified log-rank test); 24-month progression-free survival was 72% (95% confidence interval [CI], 64 to 79) with nivolumab plus ipilimumab as compared with 14% (95% CI, 6 to 25) with chemotherapy. At 24 months, the restricted mean survival time was 10.6 months (95% CI, 8.4 to 12.9) longer with nivolumab plus ipilimumab than with chemotherapy, a finding consistent with the primary analysis of progression-free survival. Grade 3 or 4 treatment-related adverse events occurred in 23% of the patients in the nivolumab-plus-ipilimumab group and in 48% of the patients in the chemotherapy group. Conclusions Progression-free survival was longer with nivolumab plus ipilimumab than with chemotherapy among patients who had not previously received systemic treatment for MSI-H or dMMR metastatic colorectal cancer.

Background: CheckMate 8HW prespecified dual primary endpoints, assessed in patients with centrally confirmed microsatellite instability-high or mismatch repair-deficient status: progression-free survival with nivolumab plus ipilimumab compared with chemotherapy as first-line therapy and progression-free survival with nivolumab plus ipilimumab compared with nivolumab alone, regardless of previous systemic treatment for metastatic disease. In our previous report, nivolumab plus ipilimumab showed superior progression-free survival versus chemotherapy in first-line microsatellite instability-high or mismatch repair-deficient metastatic colorectal cancer in the CheckMate 8HW trial. Here, we report results from the prespecified interim analysis for the other primary endpoint of progression-free survival for nivolumab plus ipilimumab versus nivolumab across all treatment lines. Methods: CheckMate 8HW is a randomised, open-label, international, phase 3 trial at 128 hospitals and cancer centres across 23 countries. Immunotherapy-naive adults with unresectable or metastatic colorectal cancer across different lines of therapy and microsatellite instability-high or mismatch repair-deficient status per local testing were randomly assigned (2:2:1) to nivolumab plus ipilimumab (nivolumab 240 mg, ipilimumab 1 mg/kg, every 3 weeks for four doses; then nivolumab 480 mg every 4 weeks; all intravenously), nivolumab (240 mg every 2 weeks for six doses, then 480 mg every 4 weeks; all intravenously), or chemotherapy with or without targeted therapies. The dual independent primary endpoints were progression-free survival by blinded independent central review with nivolumab plus ipilimumab versus chemotherapy (first line) and progression-free survival by blinded independent central review with nivolumab plus ipilimumab versus nivolumab (all lines) in patients with centrally confirmed microsatellite instability-high or mismatch repair-deficient metastatic colorectal cancer. This study is registered with ClinicalTrials.gov (NCT04008030). Findings: Between Aug 16, 2019, and April 10, 2023, 707 patients were randomly assigned to nivolumab plus ipilimumab (n=354) or nivolumab alone (n=353). 296 (84%) of 354 patients in the nivolumab plus ipilimumab group and 286 (81%) of 353 patients in the nivolumab group were centrally confirmed to have microsatellite instability-high or mismatch repair-deficient status. At the data cutoff on Aug 28, 2024, median follow-up (from randomisation to data cutoff) was 47·0 months (IQR 38·4 to 53·2). Nivolumab plus ipilimumab treatment showed significant and clinically meaningful improvement in progression-free survival versus nivolumab (hazard ratio 0·62, 95% CI 0·48–0·81; p=0·0003). Median progression-free survival was not reached with nivolumab plus ipilimumab (95% CI 53·8 to not estimable) and was 39·3 months with nivolumab (22·1 to not estimable). Treatment-related adverse events of any grade occurred in 285 (81%) of 352 patients receiving nivolumab plus ipilimumab and in 249 (71%) of 351 patients receiving nivolumab; grade 3 or 4 treatment-related adverse events occurred in 78 (22%) and 50 (14%) patients, respectively. There were three treatment-related deaths: one event of myocarditis and pneumonitis each in the nivolumab plus ipilimumab group and one pneumonitis event in the nivolumab group. Interpretation: Nivolumab plus ipilimumab showed superior progression-free survival versus nivolumab across all treatment lines, with a manageable safety profile, in patients with microsatellite instability-high or mismatch repair-deficient metastatic colorectal cancer. These results, together with the first-line results of superior progression-free survival with nivolumab plus ipilimumab versus chemotherapy, suggest nivolumab plus ipilimumab as a potential new standard of care for patients with microsatellite instability-high or mismatch repair-deficient metastatic colorectal cancer. Funding: Bristol Myers Squibb and Ono Pharmaceutical.

Nonproportional response of scintillation light yield for sub-MeV radiations is a well-known characteristic of inorganic scintillators. In the PIKACHU experiment, a precise understanding of the nonproportional response of the GAGG ($\mathrm{Ce:Gd_3Al_2Ga_3O_{12}}$) scintillator is essential for background modeling. In this study, the nonproportional response of the GAGG scintillator was evaluated for both $β$ and $γ$ rays. The response for $β$ rays was measured using the Compton coincidence technique with a germanium detector, while that for $γ$ rays was evaluated using several monoenergetic $γ$-ray sources. The measurement results showed different responses for $β$ and $γ$ rays, with a stronger nonproportional response for $γ$ rays than for $β$ rays over the energy range of 50--2614~keV. The background model incorporating the measured nonproportional responses reproduced the measured background spectra more accurately compared with the model without the nonproportional response correction. These results demonstrate the importance of precise evaluation of the nonproportional response of the GAGG scintillator which is essential not only for background modeling in the PIKACHU experiment but also for accurate energy calibration in scintillator-based experiments.

We propose a model that interpolates between quantum walks and persistent (correlated) random walks using one parameter on the one-dimensional lattice. We show that the limit distribution is described by the normal variance mixture with the arcsine law.

Purpose: Activated Notch receptor signaling has been implicated in tumor growth and progression in colorectal cancer (CRC). However, the pathogenic relevance of NOTCH gene alterations remains unclear. The aim of this study was to clarify mutational landscapes and assess their clinical significance in patients with metastatic CRC. Methods: Pre-chemotherapy tumor tissues obtained from 1154 metastatic CRC patients in the Nationwide Cancer Genome Screening Project in Japan between April 2017 and March 2019 were studied using the Oncomine Comprehensive Assay. Results: The frequencies of NOTCH1, NOTCH2, and NOTCH3 nonsynonymous sequence variants were 11.5%, 4.4%, and 10.4%, respectively. The majority of variants were missense of unknown significance that were distributed across all domains of all three NOTCH genes. The gain-of-function mutations in NOTCH reported in multiple malignancies were not identified. The NOTCH amplification rate was less than 1%. No NOTCH fusions were detected. In patients who were registered before, or within 1 year of, first-line chemotherapy, overall survival for 51 patients with only NOTCH3 variants was significantly longer than for 540 patients with no NOTCH variants (median, 40.2 months vs 27.7 months; P = 0.04). Multivariate analysis revealed that variant NOTCH3 was an independent prognostic factor for increased survival (hazard ratio 0.61, 95% confidence interval, 0.39–0.94; P = 0.03) besides poor prognostic factors associated with mutant TP53, KRAS, and BRAF, as well as amplified MYC. Conclusion: NOTCH genes are unlikely to harbor driver mutations and amplifications in patients with metastatic CRC. NOTCH3 variant should be further investigated as a favorable prognostic marker.

Purpose: HER2-targeted therapies in ERBB2-amplified metastatic colorectal cancer (mCRC) are effective; however, a notable portion of patients do not respond to treatment, and secondary resistance occurs in most patients receiving these treatments. The purpose of this study was to investigate determinants of treatment efficacy and resistance in patients with ERBB2-amplified mCRC who received HER2-targeted therapy by analyzing multiomics data. Experimental Design: We investigated genomic data from a nationwide large cancer genomic screening project, the SCRUMJapan project. We analyzed paired genome and transcriptome data of tissue and genomic data of ctDNA collected pre- and postprogression in patients enrolled in the related trial, TRIUMPH, in ERBB2-amplified mCRC. Results: In 155 patients with ERBB2-amplified solid tumors who received HER2-targeted therapy based on the SCRUM-Japan project, the objective response rate was 50%, 51%, and 35% in ERBB2 wild-type, variant of unknown significance, and pathogenic variant groups, respectively. In the paired genome and transcriptome data analyses in TRIUMPH, we identified the novel splicing-associated variant c.644-66_-2del in one of the 11 patients with paired whole-exome sequencing and wholetranscriptome sequencing data sets, which lacks the binding domain of pertuzumab, in progressed metastatic tumor as a variant with potential pathogenicity. The time-course ctDNA analysis detected c.644-66_-2del as an acquired variant. Conclusions: This study highlighted the importance of ERBB2 genomic status when evaluating the efficacy of HER2-targeted therapies in ERBB2-amplified mCRC. The identification of a novel splicing-associated variant may provide insights into potential mechanisms of treatment resistance. Furthermore, we demonstrated the utility of ctDNA to follow the acquired genomic status of mCRC tumors.

Chemoradiotherapy (CRT) followed by radical surgery is one of the standard therapies for patients with locally advanced rectal cancer (LARC). Various combination therapies have been developed to improve the efficacy of preoperative therapies. One promising approach is the combination of ionizing radiation and immune checkpoint inhibitors (ICIs) because it enhances both local and distal immunogenic efficacy according to several xenograft models. To date, promising short-term efficacy results of 23% to 37.5% of the pathological complete response (pCR) rate have been reported in clinical trials investigating the combination of CRT and ICIs in patients with microsatellite stable (MSS) LARC. In patients with high-level microsatellite instability (MSI-H) LARC, CRT followed by ICI also achieved a 60% (3/5) pCR rate according to the data of the VOLTAGE study, suggesting increased efficacy of ICIs in this subgroup, albeit with a small sample size. In patients with MSS LARC, programmed cell death-ligand 1 tumor proportion score positivity, elevated CD8/effector regulatory T cell ratio, higher immune-score, consensus molecular subtype 1, and higher tumor mutational burden appear to be positive predictors of ICIs efficacy. In addition, various prospective studies combining CRT with ICI, chemotherapy, and target agents are currently being conducted. To confirm the survival benefits of these approaches, confirmatory phase III trials are needed.

Metabolic dysregulation is a major hallmark of cancer, making interventions that modify tumor nutrient availability attractive adjuvants for improving clinical outcomes for patients with cancer. Clarifying how the nutritional status of individual patients affects the metabolic vulnerability of tumors to drugs is needed to inform personalized treatment guidelines. Working toward the goal of oncometabolic precision medicine, we developed the cancer metabolism–based synthetic lethality platform (CM-SLP), a high-throughput screening platform that explores the metabolic vulnerability of cancer cells to nononcology drugs induced by altered nutrient availability and predicts potential synthetic lethal interactions with nutrient conditions. Promising CM-SLP candidates included propafenone and biguanides as representative nononcology drugs that cooperatively enhanced cytotoxicity via dysregulated metabolic pathways. Furthermore, the mTOR and Hippo pathways mediated the response to combined propafenone/hypoglycemia or biguanides/hypoglycemia treatments, respectively, and mTOR or TEAD inhibitors circumvented the need for dietary interventions to enhance cancer cell death. Together, these results indicate that CM-SLP represents a promising approach for integrating metabolic profiling into precision oncology, offering therapeutic avenues tailored to individual patient needs. Significance: A high-throughput screening approach investigating drug vulnerabilities dependent on nutrient status supports repurposing FDA-approved compounds as metabolically informed therapies for next-generation oncometabolic precision medicine.