Targeting SNCA in the treatment of malignant ascites in gastrointestinal cancer.

Peritoneal tumor dissemination and subsequent malignant tumor ascites (MTA) occur unexpectedly and repeatedly in patients with gastrointestinal (GI) cancers, and worsen quality of life and prognosis of the patients. Various treatments have been clinically developed for these patients, while most of the MTA cases are refractory to the treatments. Thus, effective treatments are urgently needed to improve the clinical outcomes. In this study, we identified α-synuclein (SNCA) as an immunological determinant of MTA progression in GI cancer through translational research using mouse tumor models and clinical specimens collected from gastric cancer patients. We found that the SNCA+ subsets were significantly increased in CD3+ T cells, CD56+ NK cells, and CD11b+ myeloid cells within MTA and peripheral blood cells (PBCs) of MTA cases, albeit almost absent in PBCs of healthy donors, and spleen of naive mice. Of note, the SNCA+ T-cell subset was rarely seen in patients that intraperitoneal lavage fluid without tumor cells was collected before surgery as a tumor-free control, suggesting a possible cancer-induced product, especially within the peritoneal cavity. In vivo treatment with anti-SNCA blocking mAb significantly induced anti-tumor effects in mouse MTA models, and synergistically improved anti-PD1 therapeutic efficacy, providing a significantly better prognosis. These suggest that SNCA is involved in severe immunosuppression in the MTA cases, and that blocking SNCA is effective in dramatically improving the immune status in the hosts. Targeting SNCA will be a promising strategy to improve clinical outcomes in the treatment of GI cancer patients, especially with MTA.

Efficacy of anti-epidermal growth factor antibody rechallenge in RAS/BRAF wild-type metastatic colorectal cancer: a multi-institutional observational study.

PURPOSE: To investigate circulating tumor DNA (ctDNA) RAS mutant (MT) incidence before salvage-line treatment and the clinicopathological features and molecular biological factors associated with the efficacy of anti-epithelial growth factor receptor (EGFR) monoclonal antibody (mAb) rechallenge for tissue RAS/BRAF wild type (WT) metastatic colorectal cancer (mCRC). METHODS: This multi-institutional retrospective observational study included 74 patients with mCRC with tissue RAS/BRAF WT refractory to first-line chemotherapy containing anti-EGFR mAb. ctDNA RAS status was assessed using the OncoBEAM™ RAS CRC Kit. We explored the clinicopathological features associated with ctDNA RAS status and the factors related to anti-EGFR mAb rechallenge efficacy in multivariate Cox proportional hazard regression. RESULTS: The incidence of RAS MT in ctDNA was 40.5% (30/74), which was associated with primary tumor resection (P = 0.016), liver metastasis (P < 0.001), and high tumor marker levels (P < 0.001). Among the 39 patients treated with anti-EGFR mAb rechallenge, those with ctDNA RAS WT showed significantly longer progression-free survival (PFS) than those with ctDNA RAS MT (median 4.1 vs. 2.7 months, hazard ratio [HR] = 0.39, P = 0.045). Patients who responded to first-line anti-EGFR mAb showed significantly longer PFS (HR = 0.21, P = 0.0026) and overall survival (OS) (HR = 0.23, P = 0.026) than those with stable disease. CONCLUSIONS: The incidence of ctDNA RAS MT mCRC was 40.5%, which was associated with liver metastases and high tumor volumes. Anti-EGFR mAb rechallenge may be effective for patients with mCRC who responded to first-line chemotherapy containing anti-EGFR mAb. No patients with RAS MT in ctDNA responded to anti-EGFR mAb rechallenge.

Impact of immune checkpoint inhibitors on survival outcomes in advanced gastric cancer in Japan: A real-world analysis.

BACKGROUND: Nivolumab was approved for the treatment of advanced gastric cancer in 2017 in Japan. The aim of this study was to assess the impact of nivolumab in a real-world clinical setting. METHODS: This single-institutional retrospective study included patients with advanced gastric or esophagogastric junction adenocarcinoma and a history of first-line chemotherapy with platinum-based doublet or triplet regimens between 2010 and 2020. To assess the impact of nivolumab on survival, the patients were divided based on the year of nivolumab approval into a pre-2017 (2010-2016) group and a post-2017 (2017-2020) group. RESULTS: From a total of 1918 patients, 1093 were excluded. There were 533 patients in the pre-2017 group and 292 in the post-2017 group. Immune checkpoint inhibitors were used significantly more often in the post-2017 group than in the pre-2017 group (8.6% vs. 47.9%). Median overall survival was significantly longer in the post-2017 group (16.9 vs. 13.9 months; hazard ratio [HR] 0.75, 95% confidence interval [CI] 0.63-0.90; p < 0.01). The proportion of patients transitioning to third-line treatment was higher in the post-2017 group than in the pre-2017 group (56.3% vs. 43.8%, p < 0.01). Median survival outcomes following progression on second-line treatment were significantly longer in the post-2017 group (4.3 vs. 3.2 months; HR 0.70, 95% CI 0.57-0.86; p < 0.01). CONCLUSION: The proportion of patients transitioning to third-line treatment and survival outcomes following progression on second-line treatment have improved since the approval of nivolumab. This drug might help to prolong overall survival in real-world practice.

BRAF V600E-mutant colorectal cancer with CNS metastases treated successfully with encorafenib, binimetinib and cetuximab.

This report describes a case of BRAF V600E-mutated colorectal cancer with CNS metastases in which treatment with encorafenib, binimetinib and cetuximab was effective. There is limited information on the ability of encorafenib, binimetinib and cetuximab to enter the CNS.The patient was a 53-year-old man was diagnosed with ascending colon cancer (cT3N3M1c stage IVc). BRAF V600E mutation was confirmed. FOLFOX was started, but CNS metastases soon appeared. Encorafenib, binimetinib and cetuximab were administered and had a favorable effect on the CNS lesions. The patient initially responded well, but his disease progressed 2 months later. Further research is needed to improve management strategies for BRAF V600E-mutated colorectal cancer with CNS metastases.

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CRP and soluble CTLA4 are determinants of anti-PD1 resistance in gastrointestinal cancer.

Targeting immune inhibitory checkpoint (IC) pathways have attracted great attention as a promising strategy for treating gastrointestinal (GI) cancer. However, the therapeutic efficacy is low in most cases, and little progress has been made in establishing biomarkers that predict the possible responses, and combination regimens that enhance the therapeutic efficacy. As a predictive biomarker, soluble forms of IC molecules have been recently highlighted. However, little is known about which IC molecules is most critically associated with the treatment resistance, and also about the biological and immunological roles of the IC molecules in GI cancer. In this study, we analyzed sera obtained from advanced gastric cancer patients before and one month after treatment with anti-PD1 nivolumab for soluble IC molecules by ELISA. We found that decrease of soluble CTLA4 (sCTLA4) at posttreatment were significantly associated with a better prognosis, and combination with low level of CRP at posttreatment more clearly defined anti-PD1 responders with long-term survival. Indeed, in the in vitro setting, CRP stimulation upregulated CTLA4 expression in tumor cells followed by generation of sCTLA4 that suppressed CTL induction, and simultaneously conferred high self-renewal and invasive abilities on the tumor cells accompanied by increase of EMT-related gene expressions. In the in vivo setting, CRP injection elevated sCTLA4 level in sera of mouse tumor metastasis models, leading to failure of anti-PD1 therapy. However, treatment with anti-CTLA4 mAb or a PPARγ agonist that can reduce in vivo CRP successfully elicited anti-tumor efficacy in the anti-PD1 resistant models. These suggest that targeting CRP and sCTLA4 may be a promising strategy for improving clinical outcomes in the treatments, including anti-PD1 therapy, of GI cancer.

Switching from FOLFIRI plus cetuximab to FOLFIRI plus bevacizumab based on early tumor shrinkage in RAS wild-type metastatic colorectal cancer: A phase II trial (HYBRID).

BACKGROUND: Long-term anti-EGFR antibody treatment increases the risk of severe dermatologic toxicities. This single-arm, phase II trial aimed to investigate the strategy of switching from cetuximab to bevacizumab in combination with FOLFIRI based on early tumor shrinkage (ETS) in patients with RAS wild-type metastatic colorectal cancer (mCRC). METHODS: Radiologic assessment was performed to evaluate ETS, defined as ≥20% reduction in the sum of the largest diameters of target lesions 8 weeks after the introduction of FOLFIRI plus cetuximab. ETS-negative patients switched to FOLFIRI plus bevacizumab, whereas ETS-positive patients continued FOLFIRI plus cetuximab for eight more weeks, with a switch to FOLFIRI plus bevacizumab thereafter. The primary endpoint was progression-free survival. RESULTS: This trial was prematurely terminated due to poor accrual after a total enrollment of 30 patients. In 29 eligible patients, 7 were ETS-negative and 22 were ETS-positive. Two ETS-negative patients and 17 ETS-positive patients switched to FOLFIRI plus bevacizumab 8 weeks and 16 weeks after initial FOLFIRI plus cetuximab, respectively. Median progression-free and overall survival durations were 13.4 and 34.7 months, respectively. Six (20%) patients experienced grade ≥3 paronychia, which improved to grade ≤2 by 18 weeks. Grade ≥3 acneiform rash, dry skin, and pruritus were not observed in any patients. CONCLUSIONS: Our novel treatment strategy delivered acceptable survival outcomes and reduced severe dermatologic toxicities.

Exploratory analysis of serum HER2 extracellular domain for HER2 positive gastric cancer treated with SOX plus trastuzumab.

BACKGROUND: The aim of this study was to explore the clinical utility of serum HER2 extracellular domain (sHER2 ECD) using data from a clinical trial evaluating trastuzumab combined S-1 plus oxaliplatin (SOX) in HER2 positive gastric cancer. METHODS: sHER2 ECD were prospectively measured at baseline and subsequent treatment courses. Based on each quantile point of baseline sHER2 ECD levels and its early changes, patients were divided into two groups and compared clinical outcomes. RESULTS: 43 patients were enrolled, and 17 patients (39.5%) were positive for baseline sHER2 ECD. Higher baseline sHER2 ECD levels tended to have lower hazard ratios (HRs). When divided into two groups by baseline sHER2 ECD of 19.1 ng/ml, median progression-free survival (PFS) and overall survival (OS) was longer in the higher group (mPFS: 16.8 vs 8.7 months, p = 0.359. mOS: 35.5 vs 20.6 months, p = 0.270), respectively. After initiation of treatment, sHER2 ECD significantly decreased up until the third cycle. Higher reduction rates of sHER2 ECD within 3 cycles also tended to have lower HRs. When divided into two groups by reduction rate of 42.5%, mPFS and mOS was longer in the higher reduced group (mPFS: 17.2 vs 8.7 months, p = 0.095. mOS: 65.0 vs 17.8 months, p = 0.047), respectively. Furthermore, higher reduction rates could surrogate higher objective response rates (ORR) (ORR: 90% vs 63.2% for 29.5%, p = 0.065. 100% vs 70% for 42.5%, p = 0.085), respectively. CONCLUSIONS: Baseline sHER2 ECD levels and its early decline may be useful biomarkers for SOX plus trastuzumab efficacy in HER2 positive gastric cancer.

A Phase II Study of FOLFIRI Plus Ziv-Aflibercept After Trifluridine/Tipiracil Plus Bevacizumab in Patients with Metastatic Colorectal Cancer: WJOG 11018G.

BACKGROUND: Non-inferiority of trifluridine/tipiracil (FTD/TPI) plus bevacizumab (BEV) to irinotecan/fluoropyrimidine plus BEV in metastatic colorectal cancer was investigated in the phase III TRUSTY study, and we conducted a phase II study of FOLFIRI (5-FU+leucovorin+irinotecan) plus zib-aflibercept (AFL) after FTD/TPI plus BEV. However, the TRUSTY study failed during the recruitment of our patients. OBJECTIVE: We present the findings of a phase II study on the efficacy of FOLFIRI plus zib-aflibercept (AFL) after FTD/TPI plus BEV, including clinical results with plasma biomarker analyses. METHODS: This was a multicenter, single-arm, phase II study in patients with metastatic colorectal cancer refractory or intolerant to oxaliplatin, fluoropyrimidine, BEV, and FTD/TPI. The primary endpoint was progression-free survival. Fifteen plasma angiogenesis-associated biomarkers were analyzed using a Luminex® multiplex assay U-kit. RESULTS: Between January 2020 and May 2022, 26 patients (median age, 68 years) from 15 sites were enrolled. The median progression-free survival was 4.9 months (85% confidence interval, 3.4 month-not estimated). The overall response and disease control rates were 8% and 62%, respectively. The median levels of vascular endothelial growth factor-A and placental growth factor, both targets of AFL, were below the measurable limit of 30 pg/mL and 16 pg/mL, respectively. Patients were divided into two groups at the median levels of baseline biomarkers. The progression-free survival did not differ between high and low expressers of placental growth factor (p = 0.7), while it tended to be shorter in those with high levels of osteopontin (p = 0.05), angiopoietin-2 (p = 0.07), and tissue inhibitor of matrix metalloproteinases-1 (p = 0.1). CONCLUSIONS: This study did not meet the primary endpoint. Hence, FOLFIRI plus AFL should not be used after FTD/TPI plus BEV for metastatic colorectal cancer. Further studies are needed to determine factors not targeted by AFL that may affect the efficacy of the treatment. CLINICAL TRIAL REGISTRATION: jRCTs041190100.

Preoperative docetaxel, cisplatin, and 5-fluorouracil for resectable locally advanced esophageal and esophagogastric junctional adenocarcinoma.

BACKGROUND: Chemotherapy consisting of 5-fluorouracil, leucovorin, oxaliplatin, and docetaxel is the standard perioperative treatment for resectable esophageal adenocarcinoma and esophagogastric junctional adenocarcinoma (EGJ-AC) in Western countries. Meanwhile, preoperative chemotherapy consisting of docetaxel, cisplatin, and 5-fluorouracil (DCF) has been developed for esophageal squamous cell carcinoma in Japan. However, there are few reports on the safety and efficacy of preoperative DCF for resectable EGJ-AC in the Japanese population. METHODS: Patients with histologically confirmed resectable EGJ-AC who received preoperative DCF (docetaxel 70 mg/m2 and cisplatin 70 mg/m2 on day 1 and continuous infusion of 5-fluorouracil 750 mg/m2/day on days 1-5 every 3 weeks with a maximum of three cycles) between January 2015 and April 2020 were retrospectively evaluated. We assessed the rates of completion of ≥ 2 courses of DCF and R0 resection, histopathological response, progression-free survival (PFS), overall survival (OS), and adverse events. RESULTS: Thirty-two patients were included. Median follow-up was 28.7 (range, 5.2-70.8) months and median age was 63 (range, 42-80) years. Twenty-one patients (66%) had a performance status of 0. The proportions of clinical stage IIA/IIB/III/IVA/IVB disease were 3%/0%/44%/44%/9%, respectively. The treatment completion rate was 84%. A histopathological response of grade 1a/1b/2/3 was obtained in 58%/26%/13%/3% of cases. Median PFS was 40.7 months (95% confidence interval 11.8-NA). Median OS was not reached (80.8% at 3 years). Grade ≥ 3 adverse events were observed in 63% of cases (neutropenia, 44%; febrile neutropenia, 13%). No treatment-related deaths occurred. CONCLUSIONS: Preoperative DCF for resectable EGJ-AC was well tolerated and has promising efficacy.

Retrospective Analysis of Definitive Chemoradiotherapy With FOLFOX in Patients With Esophageal Cancer Intolerant to Cisplatin.

BACKGROUND/AIM: Definitive chemoradiotherapy with cisplatin (CDDP) plus 5-fluorouracil is the standard treatment for locally advanced esophageal squamous cell carcinoma (LA-ESCC); however, CDDP is unsuitable for patients with cardiac and/or renal dysfunction. Based on the results of the PRODIGE5/ACCORD17 trial, 5-fluorouracil and leucovorin with oxaliplatin plus radiotherapy (FOLFOX-RT) has been recognized as a treatment option. However, the efficacy and safety of FOLFOX-RT is still unclear in Japan. PATIENTS AND METHODS: Medical records were reviewed for patients with LA-ESCC who received FOLFOX-RT between April 2019 and July 2021 at our institution. We evaluated complete response rate, progression-free survival (PFS), overall survival (OS), and adverse events. RESULTS: Fifteen patients were analyzed and median age was 72.5 years (range=51-83 years). All patients completed three courses of FOLFOX and the planned radiotherapy. The complete response rate was 40.0%. With a median follow-up of 10.6 months, the 6-month PFS rate was 63.0% (95%CI=32.3-82.8%), and the 6-month OS rate was 85.7% (95%CI=53.9-96.2%). Common adverse events were esophagitis (80.0%), leukopenia (53.3%), fatigue (53.3%), and neutropenia (46.7%). Only one patient had grade 4 esophageal perforation. CONCLUSION: FOLFOX-RT for LA-ESCC was well tolerated and could be a treatment option for CDDP-intolerant patients.

Trastuzumab deruxtecan in patients with locally advanced or metastatic HER2-positive gastric cancer: a multicenter, open-label, expanded-access study.

BACKGROUND: Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate that consists of an anti-human epidermal growth factor receptor 2 (HER2) antibody bound by a cleavable tetrapeptide-based linker to a cytotoxic topoisomerase I inhibitor. Prior to marketing approval in Japan in September 2020, this expanded-access study was conducted to provide T-DXd to previously treated patients with locally advanced or metastatic HER2-positive gastric or gastroesophageal junction adenocarcinomas. METHODS: This multicenter, open-label, expanded-access study was conducted between March 25 and September 25, 2020 at 17 Japanese sites. Previously treated patients with locally advanced or metastatic HER2-positive gastric or gastroesophageal junction adenocarcinomas received T-DXd 6.4 mg/kg via intravenous infusions at 3-week intervals. Serious adverse events (SAEs), all potential cases of interstitial lung disease (ILD)/pneumonitis, all liver-related events potentially meeting Hy's Law criteria, and all cases of overdose were reported on the case report forms. RESULTS: A total of 64 patients were treated with T-DXd. Among the 17 (26.6%) patients with reported SAEs, 10 (15.6%) had SAEs related to T-DXd treatment. Febrile neutropenia was the most common SAE (n = 6). SAEs led to death in six patients; drug-related SAEs (sepsis and febrile neutropenia) led to death in one patient. Drug-related ILD, as determined by the external Adjudication Committee, occurred in three patients (Grade 1, Grade 2, and Grade 3: all n = 1). CONCLUSION: This expanded-access study provided T-DXd to a broader population of Japanese patients prior to marketing approval in Japan, bridging the gap between clinical trials and drug approval. No new safety concerns were identified.

Real-World Treatment Sequencing in Vulnerable Patients with Metastatic Colorectal Cancer: A Multicenter Retrospective Study.

BACKGROUND: Data regarding treatment sequence for vulnerable patients with metastatic colorectal cancer (mCRC) in a real-world setting are lacking. OBJECTIVE: We aimed to assess treatment outcomes in second-line or later chemotherapy for vulnerable patients with mCRC in a real-world setting. PATIENTS AND METHODS: Vulnerable patients with mCRC who received less intensive treatment ('vulnerable') regimens, i.e. fluoropyrimidines with or without biologics (FP), reduced-dose doublet regimens with or without biologics (Doublet), and anti-epidermal growth factor receptor monotherapy (Anti-EGFR), as first-line therapy between June 2015 and December 2018 were retrospectively reviewed. RESULTS: A total of 210 patients from 15 hospitals were analyzed. The median age was 78 years (range 28-90), and 44 patients (21%) had an Eastern Cooperative Oncology Group performance status (ECOG PS) score of 2. In the entire population, the median time to treatment failure (TTF) and overall survival (OS) were 7.6 and 21.4 months, respectively. Following the failure of first-line therapy in 195 patients, 74 (38%), 24 (12%), and 13 (7%) patients received vulnerable regimens, full-dose doublet regimens with or without biologics, and other regimens, respectively, whereas 84 (43%) received best supportive care (BSC). In patients receiving vulnerable regimens as second-line therapy, the median TTF and OS were 4.4 and 13.7 months, respectively, while response rate and disease control rate were 18% and 62%, respectively. In 84 patients who received BSC, the median OS was 3.5 months. CONCLUSIONS: Second-line chemotherapy for vulnerable patients with mCRC showed clinically meaningful outcomes; however, few patients received second-line therapy, and survival among patients who received BSC was dismal.

Travel Time and Distance and Participation in Precision Oncology Trials at the National Cancer Center Hospital.

Importance: Genotype-matched trials, which are becoming increasingly important in the precision oncology era, require referrals from institutions providing comprehensive genomic profiling (CGP) testing to those conducting these trials, and the travel burden for trial participation is significant. However, it remains unknown whether travel time or distance are associated with genotype-matched trial participation. Objective: To assess whether travel time or distance are associated with disparities in genotype-matched trial participation following CGP testing. Design, Setting, and Participants: This retrospective cohort study from June 2020 to June 2022 included patients with advanced or metastatic solid tumors referred to the National Cancer Center Hospital for participation in genotype-matched trials following CGP testing and discussion by molecular tumor boards. Data were analyzed from June to October 2022. Exposures: Travel time and distance. Main Outcomes and Measures: The primary and secondary outcomes were enrollment in genotype-matched trials and all-cancer clinical trials, respectively. Results: Of 1127 patients (mean [range] age, 62 [16-85] years; 584 women [52%]; all residents of Japan), 127 (11%) and 241 (21%) were enrolled in genotype-matched trials and all-cancer clinical trials, respectively. The overall median (IQR) travel distance and time were 38 (21-107) km and 55 (35-110) minutes, respectively. On multivariable regression with 23 covariates, travel distance (≥100 km vs <100 km) was not associated with the likelihood of genotype-matched trial participation (26 of 310 patients [8%] vs 101 of 807 patients [12%]; odds ratio [OR], 0.64; 95% CI, 0.40-1.02), whereas in patients with travel time of 120 minutes or more, the likelihood of genotype-matched trial participation was significantly lower than those with travel time less than 120 minutes (19 of 276 patients [7%] vs 108 of 851 patients [13%]; OR, 0.51; 95% CI, 0.29-0.84). The likelihood of genotype-matched trial participation decreased as travel time increased from less than 40 (38 of 283 patients [13%]) to 40 to 120 (70 of 568 patients [12%]) and 120 or more (19 of 276 patients [7%]) minutes (OR, 0.74; 95% CI, 0.48-1.17; OR, 0.41; 95% CI, 0.22-0.74, respectively). Neither travel time nor distance were associated with the likelihood of all-cancer clinical trial participation. Conclusions and Relevance: In this cohort study of patients undergoing CGP testing, an increased travel time was associated with a decreased likelihood of genotype-matched trial participation. This warrants further research on interventions, such as decentralization of clinical trials to mitigate travel burden.

A multi-institutional observational study evaluating the incidence and the clinicopathological characteristics of NeoRAS wild-type metastatic colorectal cancer.

PURPOSE: As circulating tumor DNA (ctDNA) measurement becomes more widespread, the "NeoRAS" phenomenon, where tissue rat sarcoma viral oncogene homolog (RAS) status converts from mutant (MT) to wild-type (WT) after treatment in metastatic colorectal cancer (mCRC), is gaining attention because ineffective epidermal growth factor receptor (EGFR) inhibitors may made effective. This study investigated its incidence and clinicopathological characteristics. PATIENTS AND METHODS: In total, 107 mCRC patients (refractory or intolerant to previous chemotherapies) with tissue RAS MT were enrolled in four institutions from June 2021 to August 2022. The RAS status in ctDNA was assessed using OncoBEAM™ RAS CRC assay. Clinicopathologic features were compared between patients according to their RAS status in ctDNA, whether WT conversion was noted or not. RESULTS: The incidence rate of NeoRAS WT mCRC was 21.5% (23/107). According to tissue RAS mutation sites, NeoRAS WT frequency in patients with KRAS mutation in exon 2 was significantly lower than those in exon 3 and 4 or NRAS (18.2% [18/99] vs 62.5% [5/8], P = 0.011). Regarding clinical background, there were significant differences in NeoRAS WT frequency between male vs female patients (30.6% [19/62] vs 8.9% [4/45], P = 0.008), and absence vs presence of liver metastasis (38.6% [17/44] vs 9.5% [6/63], P < 0.001). Comparing the two groups divided by the median value, NeoRAS WT was associated with smaller tumor diameter (>60.9 mm vs ≤, 3.8% [2/53] vs 38.9% [21/54], P < 0.001), lower carcinoembryonic antigen level (>38.2 ng/ml vs ≤, 11.3% [6/53] vs 31.5% [17/54], P = 0.018), and lower carbohydrate antigen 19-9 level (>158.0 U/ml vs ≤, 9.4% [5/53] vs 33.3% [18/54], P = 0.004). In the logistic regression multivariate analysis, liver metastasis absence (Odds ratio [OR], 4.62; P = 0.019), smaller tumor diameter (OR, 7.92; P = 0.012), and tissue RAS MT in other than KRAS exon 2 (OR, 9.04; P = 0.026) were significantly related to the conversion to NeoRAS WT in ctDNA. CONCLUSIONS: Original RAS variants in tissue, tumor diameter, and liver metastasis are related to conversion to NeoRAS WT mCRC in ctDNA.

A Phase II Trial of Trifluridine/Tipiracil in Combination with Cetuximab Rechallenge in Patients with RAS Wild-Type mCRC Refractory to Prior Anti-EGFR Antibodies: WJOG8916G Trial.

BACKGROUND: Trifluridine/tipiracil (FTD/TPI) improved the overall survival in patients with metastatic colorectal cancer (mCRC) who had previously received standard chemotherapies; however, the clinical outcomes remain poor. OBJECTIVE: A multicenter phase II study aimed to assess the efficacy and safety of FTD/TPI plus cetuximab rechallenge. PATIENTS AND METHODS: Patients with histologically confirmed RAS wild-type mCRC refractory to prior anti-epidermal growth factor receptor (anti-EGFR) antibody were enrolled and treated with FTD/TPI (35 mg/m2 twice daily on days 1-5 and 8-12) plus cetuximab (initially 400 mg/m2, followed by weekly 250 mg/m2) every 4 weeks. The primary endpoint was disease control rate (DCR), expecting a target DCR of 65% and null hypothesis of 45% with 90% power and 10% one-sided alpha error. Gene alterations of RAS, BRAF, EGFR, PIK3CA, ERBB2, and MET in pre-treatment circulating tumor DNA were evaluated using the Guardant360 assay. RESULTS: A total of 56 patients (median age 60 years; left-sided tumors 91%; objective partial or complete response during the prior anti-EGFR therapy 61%) were enrolled. The DCR was 54% (80% confidence interval [CI] 44-63; P = 0.12), with a partial response rate of 3.6%. Median progression-free survival (PFS) was 2.4 months (95% CI 2.1-3.7). In the circulating tumor DNA analysis, patients without any alterations of the six genes (n = 20) demonstrated higher DCR (75% vs. 39%; P = 0.02) and longer PFS (median 4.7 vs. 2.1 months; P < 0.01) than those with any gene alterations (n = 33). The most common grade 3/4 hematologic adverse event was neutropenia (55%). No treatment-related deaths occurred. CONCLUSIONS: FTD/TPI plus cetuximab rechallenge did not demonstrate clinically meaningful efficacy in all mCRC patients, but might be beneficial for the molecularly selected population.

Perioperative TAS-118 plus oxaliplatin in patients with locally advanced gastric cancer: APOLLO-11 study.

BACKGROUND: We investigated the feasibility of perioperative chemotherapy with S-1 and leucovorin (TAS-118) plus oxaliplatin in patients with locally advanced gastric cancer. METHODS: Patients with clinical T3-4N1-3M0 gastric cancer received four courses of TAS-118 (40-60 mg/body, orally, twice daily for seven days) plus oxaliplatin (85 mg/m2, intravenously, day one) every two weeks preoperatively followed by gastrectomy with D2 lymphadenectomy, followed by postoperative chemotherapy with either 12 courses of TAS-118 monotherapy (Step 1) or eight courses of TAS-118 plus oxaliplatin (Step 2). The primary endpoints were completion rates of preoperative chemotherapy with TAS-118 plus oxaliplatin and postoperative chemotherapy with TAS-118 monotherapy (Step 1) or TAS-118 plus oxaliplatin (Step 2). RESULTS: Among 45 patients enrolled, the preoperative chemotherapy completion rate was 88.9% (90% CI 78.0-95.5). Major grade ≥ 3 adverse events (AEs) were diarrhoea (17.8%) and neutropenia (8.9%). The R0 resection rate was 95.6% (90% CI 86.7-99.2). Complete pathological response was achieved in 6 patients (13.3%). Dose-limiting toxicity was not observed in 31 patients receiving postoperative chemotherapy (Step 1, n = 11; Step 2, n = 20), and completion rates were 90.9% (95% CI 63.6-99.5) for Step 1 and 80.0% (95% CI 59.9-92.9) for Step 2. No more than 10% of grade ≥ 3 AEs were observed in patients receiving Step 1. Hypokalaemia and neutropenia occurred in 3 and 2 patients, respectively, receiving Step 2. The 3-year recurrence-free and overall survival rates were 66.7% (95% CI 50.9-78.4) and 84.4% (95% CI 70.1-92.3), respectively. CONCLUSIONS: Perioperative chemotherapy with TAS-118 plus oxaliplatin with D2 gastrectomy is feasible.

Recent advances in immunotherapy and molecular targeted therapy for gastric cancer.

Our increasing understanding of the molecular biological characteristics of cancer and of cancer genomics is facilitating the development of immunotherapy and molecular targeted drugs for gastric cancer. After the approval of immune checkpoint inhibitors (ICIs) for melanoma in 2010, many different cancers have been shown to respond to such treatments. Thus, the anti-PD-1 antibody nivolumab was reported to prolong survival in 2017, and ICIs have become the mainstay of treatment development. Many clinical trials of combination therapies with cytotoxic agents and molecular-targeted agents, as well as combinations of immunotherapeutic agents acting via different mechanisms, are currently underway for each treatment line. As a result, further improvements in therapeutic outcomes for gastric cancer are anticipated in the near future.

Gastric cancer is the fourth most common malignant tumor and also ranks fourth as a cause of death from cancer. However, even with chemotherapy, prognosis is limited to 12­15 months. The recent development of immune checkpoint inhibitors (ICIs) encourages optimism that these may represent novel standards-of-care for AGC, with clear clinical benefits. Many clinical trials of combination therapies with cytotoxic agents and molecular-targeted agents, as well as combinations of immunotherapeutic agents, are currently underway for each treatment line. As a result, further improvements in therapeutic outcomes for gastric cancer are anticipated in the near future.

Integration of pharmacoproteomic and computational approaches reveals the cellular signal transduction pathways affected by apatinib in gastric cancer cell lines.

Apatinib is known to be a highly selective vascular endothelial growth factor receptor 2 (VEGFR2) inhibitor with anti-angiogenic and anti-tumor properties. In a phase III study, the objective response rate to apatinib was low. It remains unclear why the effectivity of apatinib varies among patients and what type of patients are candidates for the treatment. In this study, we investigated the anti-tumor efficacy of apatinib against 13 gastric cancer cell lines and found that it differed depending on the cell line. Using integrated wet and dry approaches, we showed that apatinib was a multi-kinase inhibitor of c-Kit, RAF1, VEGFR1, VEGFR2, and VEGFR3, predominantly inhibiting c-Kit. Notably, KATO-III, which was the most apatinib-sensitive among the gastric cancer cell lines investigated, was the only cell line expressing c-Kit, RAF1, VEGFR1, and VEGFR3 but not VEGFR2. Furthermore, we identified SNW1 as a molecule affected by apatinib that plays an important role in cell survival. Finally, we identified the molecular network related to SNW1 that was affected by treatment with apatinib. These results suggest that the mechanism of action of apatinib in KATO-III cells is independent of VEGFR2 and that the differential efficacy of apatinib was due to differences in expression patterns of receptor tyrosine kinases. Furthermore, our results suggest that the differential efficacy of apatinib in gastric cell lines may be attributed to SNW1 phosphorylation levels at a steady state. These findings contribute to a deeper understanding of the mechanism of action of apatinib in gastric cancer cells.

Progression patterns and site-specific responses in advanced gastric cancer patients treated with nivolumab.

BACKGROUND: While the efficacy of immune checkpoint inhibitors (ICIs) reportedly varies among metastatic sites and progression patterns (classified as systemic progression [SP] or mixed progression [MP]), the clinical efficacy of ICIs against gastric cancer remains unclear. The response to nivolumab depending on metastatic site and clinical outcomes according to progression pattern in patients with advanced gastric cancer was investigated retrospectively. METHODS: Seventy-four advanced gastric cancer patients with measurable lesions who received nivolumab monotherapy between 2015 and 2020 were enrolled. Progression-free survival (PFS), overall survival, response at each metastatic site, and clinical outcomes according to progression pattern were analyzed retrospectively. SP and MP were defined as progression in more than half of the lesions and progression in half or fewer of the lesions, respectively, in cases evaluated as progressive disease. RESULTS: Thirty-five (47%) and 27 (36%) patients had SP and MP, respectively, and 12 (16%) patients experienced no progression. The progression rates of target lesions in the lung (44%) and liver (57%) were significantly higher than that in the lymph nodes (18%) (lung vs. lymph node, p < 0.001; liver vs. lymph node, p = 0.03). Patients with MP had superior PFS to those with SP (median, 2.6 vs. 1.5 months; HR, 0.42; 95% CI, 0.23-0.76; p = 0.004). In MP group, patients with treatment beyond progression (TBP) with nivolumab had a trend of longer post-progression survival than those without TBP (median, 8.0 vs. 4.0 months; HR, 0.55; 95% CI, 0.23-1.29; p = 0.161). CONCLUSION: Patients with MP had a longer PFS than those with SP. Lung and liver metastases had a poorer response to an ICI than lymph node metastases.