Three-year outcomes of preoperative chemoradiotherapy plus nivolumab in microsatellite stable and microsatellite instability-high locally advanced rectal cancer.

BACKGROUND: Preoperative chemoradiotherapy (CRT) followed by surgery is the standard treatment for locally advanced rectal cancer (LARC). We reported the short-term outcomes of the VOLTAGE trial that investigated the safety and efficacy of preoperative CRT followed by nivolumab and surgery. Here, we present the 3-year outcomes of this trial. METHODS: Thirty-nine patients with microsatellite stable (MSS) LARC and five patients with microsatellite instability-high (MSI-H) LARC underwent CRT (50.4 Gy) followed by five doses of nivolumab (240 mg) and surgery. The 3-year relapse-free survival (RFS), overall survival (OS), and associations with biomarkers were evaluated. RESULTS: The 3-year RFS rates in patients with MSS and MSI-H were 79.5% and 100%, respectively, and the 3-year OS rates were 97.4% and 100%, respectively. Of the MSS patients, those with pre-CRT PD-L1 positivity, pre-CRT high CD8 + T cell/effector regulatory T cell (eTreg) ratio, pre-CRT high expression of Ki-67, CTLA-4, and PD-1 had a trend toward better 3-year RFS than those without. CONCLUSIONS: Three-year outcomes of patients with MSI-H were better than those of patients with MSS. PD-L1 positivity, elevated CD8/eTreg ratio, and high expression of Ki-67, CTLA-4, and PD-1 could be positive predictors of prognosis in patients with MSS. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02948348.

Assessment for the timing of comprehensive genomic profiling tests in patients with advanced solid cancers.

Comprehensive genomic profiling (CGP) tests have been covered by public insurance in Japan for patients with advanced solid tumors who have completed or are completing standard treatments or do not have them. Therefore, genotype-matched drug candidates are often unapproved or off-label, and improving clinical trial access is critical, involving the appropriate timing of CGP tests. To address this issue, we analyzed the previous treatment data for 441 patients from an observational study on CGP tests discussed by the expert panel at Hokkaido University Hospital between August 2019 and May 2021. The median number of previous treatment lines was two; three or more lines accounted for 49%. Information on genotype-matched therapies was provided to 277 (63%). Genotype-matched clinical trials were ineligible because of an excess number of previous treatment lines or use of specific agents were found in 66 (15%) patients, with the highest proportion in breast and prostate cancers. Many patients met the exclusion criteria of one to two or more treatment lines across cancer types. In addition, previous use of specific agents was a frequent exclusion criterion for breast, prostate, colorectal, and ovarian cancers. The patients with tumor types with a low median number (two or fewer) of previous treatment lines, including most rare cancers, primary unknown cancers, and pancreatic cancers, had significantly fewer ineligible clinical trials. The earlier timing of CGP tests may improve access to genotype-matched clinical trials, with their proportion varying by cancer type. Each relevant society needs to advocate the desirable timing of CGP testing nationwide.

Mutational spectrum of TP53 gene correlates with nivolumab treatment efficacy in advanced gastric cancer (TP53MUT study).

BACKGROUND: Although nivolumab has a high efficacy, reliable biomarkers are needed to predict the efficacy. We evaluated the nivolumab efficacy according to the TP53 mutation in advanced gastric cancer patients enrolled in the GI-SCREEN project. METHODS: Sequence data of tumour specimens and clinicopathological information of 913 patients with advanced gastric cancer who were enrolled between April 2015 and March 2017 were obtained from the GI-SCREEN database. The follow-up information of 266 patients treated with nivolumab was also provided. RESULTS: Among 266 patients treated with nivolumab, the objective response rate (ORR) of TP53 wild type (wt) patients (24.6%) was higher than that of TP53 mutant patients (14.8%). Among TP53 mutant patients, the ORR of the frameshift type tended to be higher than the transition and transversion type (23.1%, 13.6%, and 13.0%, respectively). The median progression-free survival (PFS) was statistically longer in TP53 wt patients than in mutant patients (3.3 vs 2.1 months, HR 1.4, 95% CI 1.1-1.9). Among TP53 mutant patients, PFS was statistically longer in the frameshift type than in the transversion type. CONCLUSION: Nivolumab showed better efficacy in TP53 wt patients than in mutant patients. Among TP53 mutant patients, the frameshift type may have efficacy from nivolumab treatment.

Clinical outcomes of intensive versus less intensive first-line chemotherapy for metastatic colorectal cancer.

Aims: Physicians determine the treatment regimen for metastatic colorectal cancer on a case-by-case bases, according to the individual disease characteristics. We retrospectively compared the baseline characteristics and efficacies of first-line treatment among patients with metastatic colorectal cancer who received intensive therapy involving fluoropyrimidine plus oxaliplatin and/or irinotecan, potentially with molecularly targeted agents as well, versus less intensive fluoropyrimidine and/or bevacizumab therapy. Materials & methods: Data were collected from a medical claims database. The efficacy outcomes were: time to treatment failure, time to first subsequent therapy and overall survival. Results: The less intensive therapy group (n = 633) had higher median age, lower daily activity levels and shorter time to treatment failure, time to first subsequent therapy and overall survival than the intensive therapy group (n = 3829). Combination therapy with molecularly targeted agents and bevacizumab improved treatment efficacy outcomes in the intensive and less intensive groups, respectively. Conclusion: Patient age and daily activity levels were important factors for determining treatment intensity.

In this study we performed a real-world data analysis of treatment for advanced colorectal cancer that had spread to other parts of patients' bodies, by investigating the medical records of 4462 patients. We wanted to see how well different treatments worked and what kinds of patients received them. We found that the most important factors when choosing between different treatments were the patient's age and how well they could perform their everyday tasks. We found that using specialized medicines in the intensive treatment group, and a drug called bevacizumab in the less intensive group, resulted in better patient outcomes.

The BEETS (JACCRO CC-18) trial: an observational and translational study of BRAF-mutated metastatic colorectal cancer.

For BRAF V600E-mutated metastatic colorectal cancer (mCRC), the BEACON phase 3 trial showed survival benefit of triplet therapy with cetuximab (anti-EGFR antibody), encorafenib (BRAF inhibitor) and binimetinib (MEK inhibitor) as well as doublet therapy with cetuximab and encorafenib over irinotecan-based chemotherapy plus anti-EGFR antibody. Both regimens are standards of care in Japan, but definite biomarkers for predicting efficacy and selecting treatment remain lacking. The mechanisms underlying resistance to these regimens also warrant urgent exploration to further evolve treatment. This prospective observational/translational study evaluated real-word clinical outcomes with cetuximab and encorafenib with or without binimetinib for BRAF-mutated mCRC patients and investigated biomarkers for response and resistance by collecting blood samples before and after treatment. Clinical Trial Registration: UMIN000045530 (https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000051983).

The BEETS trial is a study that looks at how well two combinations of targeted therapies (cetuximab + encorafenib with or without binimetinib) work and how safe they are for patients with advanced colorectal cancer that has a mutation (change) in the BRAF gene. In this trial, patients participate voluntarily instead of being assigned to one of the two therapy groups. When a patient has BRAF-mutated advanced colorectal cancer, it means that the cancer cells in their body have changes in a gene called BRAF. This gene normally produces a protein called BRAF, which is involved in the growth of cells. However, when there is a mutation in this gene, it can cause the production of an overactive BRAF protein, leading to fast and excessive cell growth and division. For patients with BRAF-mutated advanced colorectal cancer, combinations of targeted therapies have been found to be effective as a second- or third-line treatment, based on the results of a phase 3 clinical trial. The main goal of the BEETS trial is to evaluate how well these treatments work and how safe they are when used in real-world clinical practice. Additionally, the study will use laboratory tests (liquid biopsy) to explore new biomarkers that can help predict how well a treatment will work and assist in selecting the most suitable treatment plans. We hope that the findings of this study will contribute to improving the overall management of this specific type of cancer.

Regulation of MEK inhibitor selumetinib sensitivity by AKT phosphorylation in the novel BRAF L525R mutant.

BACKGROUND: Oncogenic mutations in BRAF genes are found in approximately 5-10% of colorectal cancers. The majority of BRAF mutations are located within exons 11-15 of the catalytic kinase domains, with BRAF V600E accounting for more than 80% of the observed BRAF mutations. Sensitivity to BRAF- and mitogen-activated protein kinase (MEK) inhibitors varies depending on BRAF mutations and tumor cell types. Previously, we newly identified, BRAF L525R-mutation, in the activation segment of the kinase in colorectal cancer patient. Here, we characterized the function of the BRAF L525R mutation. METHODS: HEK293 cells harboring a BRAF mutation (V600E or L525R) were first characterized and then treated with cetuximab, dabrafenib, and selumetinib. Cell viability was measured using WST-1 assay and the expression of proteins involved in the extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) signaling pathways was evaluated using western blot analysis. RESULTS: The MEK inhibitor selumetinib effectively inhibited cell proliferation and ERK phosphorylation in BRAF L525R cells but not in BRAF V600E cells. Further studies revealed that AKT phosphorylation was reduced by selumetinib in BRAF L525R cells but not in BRAF V600E cells or selumetinib-resistant BRAF L525R cells. Moreover, the AKT inhibitor overcame the selumetinib resistance. CONCLUSIONS: We established a model system harboring BRAF L525R using HEK293 cells. BRAF L525R constitutively activated ERK. AKT phosphorylation caused sensitivity and resistance to selumetinib. Our results suggest that a comprehensive network analysis may provide insights to identify effective therapies.

Phase II Study of Continued Trastuzumab Plus Irinotecan in Patients with HER2-positive Gastric Cancer Previously Treated with Trastuzumab (HGCSG 1201).

BACKGROUND: The efficacy of irinotecan plus continuous trastuzumab beyond progression in patients with gastric cancer previously treated with trastuzumab plus standard first-line chemotherapy has not been reported. METHODS: Patients with human epidermal growth factor receptor 2 (HER2)-positive advanced gastric cancer who were previously treated with trastuzumab received trastuzumab every 3 weeks and irinotecan every 2 weeks. The primary endpoint was the overall response rate (ORR), and the secondary endpoints included progression-free survival (PFS), 6-month survival rates, safety, and subgroup analysis by HER2 status. RESULTS: Sixteen patients were enrolled in a 3-year pre-planned registration period. This study was prematurely closed due to poor patient accrual. The ORR and disease control rate were 6.7% (95% CI, 0.2-32.0) and 53.3% (95% CI, 26.6-78.7). The median PFS and overall survival (OS) were 2.4 months (95% CI, 0.0-5.2) and 9.7 months (95% CI, 8.2-11.2), respectively. The most frequently reported grades 3-4 adverse events were neutropenia (40%), anemia (27%), anorexia (33%), and fatigue (33%). CONCLUSION: With only 16 patients enrolled, the present study has very low power to detect any clinical benefit of trastuzumab plus irinotecan beyond disease progression in patients with HER2-positive advanced gastric cancer who previously received trastuzumab.Trial Identifier: UMIN000007636.

Phase II Study of Ramucirumab Plus Irinotecan Combination Therapy as Second-Line Treatment in Patients with Advanced Gastric Cancer: HGCSG1603.

BACKGROUND: Ramucirumab is a human IgG1 monoclonal vascular endothelial growth factor receptor-2 antibody that inhibits tumor cell growth and affects the tumor cell microenvironment. We assessed the efficacy and safety of ramucirumab plus irinotecan combination therapy as second-line treatment in patients with previously treated advanced gastric cancer. MATERIALS AND METHODS: Patients with advanced gastric cancer refractory or intolerant to primary chemotherapy were included. Ramucirumab 8 mg/kg plus irinotecan 150 mg/m2 combination therapy was administered every 2 weeks. The primary endpoint was progression-free survival rate at 6 months and secondary endpoints were overall survival, progression-free survival, response rate, safety, and dose intensity for each drug. RESULTS: Thirty-five patients were enrolled between January 2018 and September 2019. The progression-free survival rate at 6 months was 26.5% [95%CI, 13.2%-41.8%, P = .1353)]. Median progression-free and overall survivals were 4.2 months (95%CI, 2.5-5.4 months) and 9.6 months (95%CI, 6.4-16.6 months), respectively. The overall response rate was 25.9% (95%CI, 11.1-36.3%) and disease control rate was 85.2% (95%CI, 66.3-95.8%). Grade ≥3 adverse events that occurred in >10% of patients included neutropenia, leucopenia, anemia, anorexia, and febrile neutropenia. No death or new safety signals with a causal relation to the study treatment were observed. CONCLUSION: Although the primary endpoint was not achieved statistically, combination therapy of ramucirumab plus irinotecan showed anticancer activity and a manageable safety profile for second-line treatment of patients with advanced gastric cancer.

An open-label, crossover study to compare different formulations and evaluate effect of food on pharmacokinetics of pimitespib in patients with advanced solid tumors.

This study compared the bioavailability of two pimitespib formulations (Formulations A and B), evaluated the food effect on Formulation A, and evaluated the safety and efficacy of multiple pimitespib doses in patients with solid tumors. This clinical, pharmacological multicenter study had two cohorts and periods. A single dose of Formulation A or B was administered in a crossover design to compare the pharmacokinetics in Cohort 1. In Cohort 2, the effects of fed vs fasting conditions were evaluated among those receiving Formulation A. Subsequently, multiple Formulation A doses were administered to all patients for safety and efficacy assessments. In Cohorts 1 and 2, 12 and 16 patients, respectively, were analyzed for pharmacokinetics. Thirty patients were analyzed for safety and efficacy. Maximum concentration (Cmax), area under the curve (AUC)last, and AUCinf geometric mean ratios for Formulations A and B (90% confidence interval [CI]) were 0.8078 (0.6569-0.9933), 0.7973 (0.6672-0.9529), and 0.8094 (0.6697-0.9782), respectively; 90% CIs were not within the bioequivalence range (0.80-1.25). In Cohort 2, mean Cmax, AUClast, and AUCinf were higher in fed vs fasting conditions. No safety concerns emerged with single or multiple administration. Overall response rate, disease control rate, and median progression-free survival were 0%, 33%, and 1.5 months, respectively. Four patients had stable disease ≥ 5 months. Bioequivalence of the two formulations was unconfirmed. Systemic exposure of Formulation A was approximately 20% less than Formulation B. A high-fat/calorie meal increased the relative pharmacokinetics and bioavailability of a single 160-mg dose. Trial Registration: JapicCTI-184191 (Japan Pharmaceutical Information Center) registered on November 5, 2018.

Feasibility of edoxaban for asymptomatic cancer-associated thrombosis in Japanese patients with gastrointestinal cancer: ExCAVE study.

BACKGROUND: Although initial therapy with a parenteral anticoagulant is required before edoxaban, this strategy is frequently avoided in actual clinical practice because of its complexity. This study assessed the feasibility of edoxaban without initial heparin usage for asymptomatic cancer-associated thrombosis (CAT) in Japanese patients with gastrointestinal cancer (GIC) at high risk of bleeding. METHODS: In this multicenter prospective feasibility study conducted at 10 Japanese institutions, patients with active GIC who developed accidental asymptomatic CAT during chemotherapy were recruited. Edoxaban was orally administered once daily without initial parenteral anticoagulant therapy within 3 days after detecting asymptomatic CAT. The primary outcome was the incidence of major bleeding (MB) or clinically relevant non-major bleeding (CRNMB) during the first 3 months of edoxaban administration. RESULTS: Of the 54 patients enrolled from October 2017 to September 2020, one was excluded because of a misdiagnosis of CAT. In the remaining 53 patients, the primary outcome occurred in six patients (11.3%). MB occurred in four patients (7.5%), including gastrointestinal bleeding in three patients and intracranial hemorrhage in one patient. CRNMB occurred in two patients (3.8%), including bleeding from the stoma site and genital bleeding in one patient each. There were no deaths attributable to bleeding, and all patients who experienced MB or CRNMB recovered. CONCLUSIONS: The risk of bleeding after edoxaban without heparin pretreatment was acceptable, demonstrating new treatment options for asymptomatic CAT in patients with GIC.

Multicenter, prospective, observational study of chemotherapy-induced dysgeusia in gastrointestinal cancer.

PURPOSE: Dysgeusia is an adverse event caused by chemotherapy. Although retrospective studies have shown zinc administration improves dysgeusia, there have been no prospective studies. The present study examined effects of zinc therapy on dysgeusia in patients with gastrointestinal cancer. METHODS: This multicenter, prospective, observational study enrolled patients with dysgeusia during chemotherapy treatment. Patients received no intervention (control), polaprezinc p.o., or zinc acetate hydrate p.o., and serum zinc levels were measured at 0 (baseline), 6, and 12 weeks. Dysgeusia was assessed using CTCAE v5.0 and subjective total taste acuity (STTA) criteria using questionnaires at baseline and 12 weeks. RESULTS: From February 2020 to June 2021, 180 patients were enrolled from 17 institutes. There were no differences in mean baseline serum zinc levels among the groups (67.3, 66.6, and 67.5 µg/dL in the no intervention, polaprezinc, and zinc acetate hydrate groups, respectively. P = 0.846). The changes in mean serum zinc levels after 12 weeks were - 3.8, + 14.3, and + 46.6 µg/dL, and the efficacy rates of dysgeusia were 33.3%, 36.8%, and 34.6% using CTCAE and 33.3%, 52.6%, 32.7% using STTA in the no intervention, polaprezinc, and zinc acetate hydrate groups, respectively. The STTA scores improved in all groups, with significant improvement observed in the polaprezinc group compared with the no intervention group (P = 0.045). CONCLUSION: There was no significant correlation between the degree of serum zinc elevation and improvement in dysgeusia, suggesting that polaprezinc, but not zinc acetate hydrate, was effective in improving chemotherapy-induced dysgeusia. TRIAL REGISTRATION: UMIN000039653. Date of registration: March 2, 2020.

Usefulness of ultrasonography and elastography in diagnosing oxaliplatin-induced sinusoidal obstruction syndrome.

BACKGROUND: Sinusoidal obstruction syndrome (SOS) refers to liver injury caused by hematopoietic stem cell transplantation (HSCT) and anticancer drugs including oxaliplatin. Increased splenic volume (SV) on computed tomography (CT) indicates oxaliplatin-induced SOS. Similarly, ultrasonography and liver stiffness measurement (LSM) by shear-wave elastography (SWE) can help diagnose SOS after HSCT; however, their usefulness for diagnosing oxaliplatin-induced SOS remains unclear. We investigated the usefulness of the Hokkaido ultrasonography-based scoring system with 10 ultrasonographic parameters (HokUS-10) and SWE in diagnosing oxaliplatin-induced SOS early. METHODS: In this prospective observational study, ultrasonography and SWE were performed before and at 2, 4, and 6 months after oxaliplatin-based chemotherapy. HokUS-10 was used for assessment. CT volumetry of the SV was performed in clinical practice, and an SV increase ≥ 30% was considered the diagnostic indicator of oxaliplatin-induced SOS. We assessed whether HokUS-10 and SWE can lead to an early detection of oxaliplatin-induced SOS before an increased SV on CT. RESULTS: Of the 30 enrolled patients with gastrointestinal cancers, 12 (40.0%) with an SV increase ≥ 30% on CT were diagnosed with SOS. The HokUS-10 score was not correlated with an SV increase ≥ 30% (r = 0.18). The change in rate of three HokUS-10 parameters were correlated with an SV increase ≥ 30% (r = 0.32-0.41). The change in rate of LSM by SWE was correlated with an SV increase ≥ 30% (r = 0.40). CONCLUSIONS: The usefulness of HokUS-10 score was not demonstrated; however, some HokUS-10 parameters and SWE could be useful for the early diagnosis of oxaliplatin-induced SOS.

Advanced colorectal cancer subtypes (aCRCS) help select oxaliplatin-based or irinotecan-based therapy for colorectal cancer.

Oxaliplatin (OX) and irinotecan (IRI) are used as key drugs for the first-line treatment of metastatic colorectal cancer (mCRC). However, no biomarkers have been identified to decide which of the drugs is initially used. In this translational research (TR) of the TRICOLORE trial, the advanced colorectal cancer subtype (aCRCS) was analyzed as a potential biomarker for the selection of OX or IRI. We collected 335 (68.8%) formalin-fixed, paraffin-embedded (FFPE) primary tumor specimens from 487 patients registered in the TRICOLORE trial and performed direct sequencing and immunohistochemical staining of CRC-related genes, comprehensive gene-expression analysis, and genome-wide methylation analysis. The progression-free survival (PFS) of the IRI group was significantly better compared with the OX group in BRAF wild-type (WT), PTEN-positive, and aCRCS A1 patients. Among the molecular factors, aCRCS were only associated with the PFS of OX and IRI groups. The PFS of the IRI group was significantly better compared with the OX group in aCRCS A1 + B1 (hazard ratio [HR] = 0.58; 95% confidence interval [CI] = 0.41-0.82; P = .0023). In contrast, the OX group had better PFS compared with the IRI group in aCRCS B2, although this was not statistically significant (HR = 1.66; 95% CI = 0.94-2.96; P = .083). Nearly half of patients with mCRC (46.8%, aCRCS A1 + B1) respond well to IRI, while only about 18.5% (aCRCS B2) of patients with mCRC responded well to OX. In conclusion, the aCRCS might be a predictive factor for the clinical outcomes of OX-based and IRI-based therapies.

FMS-like tyrosine kinase 3 (FLT3) amplification in patients with metastatic colorectal cancer.

FMS-like tyrosine kinase 3 (FLT3) plays a key role in hematopoiesis. However, the oncogenic role of FLT3 amplification in patients with metastatic colorectal cancer (mCRC) remains unclear. Here, we aimed to evaluate the characteristics, prognosis, and treatment efficacy of an FLT3 inhibitor (regorafenib) in patients with mCRC with FLT3 amplifications. Tumor tissue samples from 2329 patients were sequenced using NGS in the Nationwide Cancer Genome Screening Project in Japan. The effects of clinicopathological features, co-altered genes, prognosis, and efficacy of regorafenib were investigated. Between April 2015 and June 2018, 85 patients with mCRC with FLT3 amplification were observed. There were no differences in baseline characteristics between patients with or without FLT3 amplification. The frequency of RAS or other gene co-alterations was inversely correlated with the copy number status. Median survival time in patients with FLT3 amplification was significantly shorter compared with those with non-FLT3 amplification. Further investigations of FLT3 amplification as a potential treatment target in mCRC are warranted.

A Phase I Trial of Oxaliplatin, Irinotecan, and S-1 Combination Therapy (OX-IRIS) as Chemotherapy for Unresectable Pancreatic Cancer (HGCSG 1403).

LESSONS LEARNED: Because S-1 is orally administered, OX-IRIS does not necessitate the continuous infusion of 5-FU and is more convenient. The recommended dose of OX-IRIS was determined to be level -1 (oxaliplatin, 65 mg/m2 ; irinotecan, 100 mg/m2 ; S-1, 80 mg/m2 ), which has manageable safety and promising anticancer activities. BACKGROUND: OX-IRIS is a new combination therapy of oxaliplatin, irinotecan, and S-1 for unresectable pancreatic ductal adenocarcinoma (PDAC), which may be beneficial because S-1 is administered orally and continuous infusion of 5-fluorouracil (5-FU) is not needed. METHODS: Patients who had not received prior therapy for unresectable PDAC were enrolled. Adenocarcinoma or adenosquamous histology was required. Oxaliplatin and irinotecan were administered on days 1 and 15; S-1 was administered orally twice a day on days 1-14, followed by 14 days of rest (one cycle). Primary endpoints were dose-limiting toxicity (DLT) and maximum tolerated dose (MTD). Secondary endpoints were safety, overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). RESULTS: In level 0 (oxaliplatin, 85 mg/m2 ; irinotecan, 100 mg/m2 ; S-1, 80 mg/m2 ), two of five patients experienced DLT. In level -1 (oxaliplatin, 65 mg/m2 ; irinotecan, 100 mg/m2 ; S-1, 80 mg/m2 ), DLT could not be evaluated in two of eight patients because one cycle was not completed; one of the remaining six patients experienced DLT. Anemia, thrombocytopenia, fatigue, nausea, anorexia, diarrhea, and peripheral sensory neuropathy were seen frequently in levels 0 and -1. ORR was 30% in levels 0 and -1. Median progression-free survival and median overall survival were 4.1 months (95% confidence interval [CI], 0.0-8.9 months) and 13.7 months (95% CI, 4.8-22.6 months), respectively. CONCLUSION: MTD of OX-IRIS therapy was estimated to be level 0, and the recommended dose (RD) for future trial was level -1.

The Prognostic Impact of KRAS G12C Mutation in Patients with Metastatic Colorectal Cancer: A Multicenter Retrospective Observational Study.

BACKGROUND: KRAS is one of the most frequently mutated oncogenes in colorectal cancer (CRC). Recently, a novel therapy targeting KRAS G12C mutation has demonstrated promising activities for corresponding advanced solid tumors, including metastatic CRC (mCRC). However, the prognostic impact of the KRAS G12C mutation remains unclear in patients with mCRC. MATERIALS AND METHODS: We retrospectively reviewed medical records of patients with mCRC who received first-line chemotherapy between January 2005 and December 2017 at four large oncology facilities in Japan. Survival outcomes were compared between patients with KRAS G12C and those with non-G12C mutations. RESULTS: Among 2,457 patients with mCRC, 1,632 met selection criteria, and of these, 696 had KRAS exon 2 mutations, including 45 with KRAS G12C mutation tumors. Patient characteristics were not significantly different between the KRAS G12C and non-G12C groups. At a median follow-up of 64.8 months, patients with the KRAS G12C mutation showed significantly shorter first-line progression-free survival (PFS; median, 9.4 vs. 10.8 months; p = .015) and overall survival (OS; median, 21.1 vs. 27.3 months; p = .015) than those with non-G12C mutations. Multivariate analysis also showed that KRAS G12C mutation was significantly associated with shorter PFS (hazard ratio [HR], 1.43; 95% confidence interval [CI], 1.04-1.96, p = .030) and OS (HR, 1.42; 95% CI, 1.01-2.00; p = .044). CONCLUSION: We demonstrate that, compared with non-G12C mutations, KRAS G12C mutation is significantly correlated with shorter first-line PFS and OS. These findings indicate the relevance of a stratified treatment targeting KRAS G12C mutation in mCRC. IMPLICATIONS FOR PRACTICE: Among patients with KRAS exon 2 mutated metastatic colorectal cancer (mCRC), median progression-free survival (PFS) and overall survival (OS) were 9.4 and 21.1 months, respectively, for G12C mutation and 10.8 and 27.3 months, respectively, for patients with non-G12C mutations, indicating significantly shorter PFS (hazard ratio [HR], 1.47; 95% confidence interval [CI], 1.08-2.01; p = .015) and OS (HR, 1.50; 95% CI, 1.08-2.08; p = .015) in patients with G12C mutation than in those with non-G12C mutations. Furthermore, multivariate analysis showed that KRAS G12C mutation was independently associated with shorter first-line PFS and OS. Thus, these findings underscore the relevance of a stratified treatment targeting KRAS G12C mutation in mCRC.

REMARRY and PURSUIT trials: liquid biopsy-guided rechallenge with anti-epidermal growth factor receptor (EGFR) therapy with panitumumab plus irinotecan for patients with plasma RAS wild-type metastatic colorectal cancer.

BACKGROUND: Previous clinical trials have demonstrated the potential efficacy of rechallenge with anti- epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) for patients with RAS/BRAF V600E wild-type metastatic colorectal cancer (mCRC). Moreover, post hoc biomarker analyses of clinical trials has suggested that RAS status in circulating tumor DNA (ctDNA) has a high probability to select patients who could benefit from anti-EGFR mAb rechallenge. METHODS: This trial is composed of 2 phases: a monitoring phase (REMARRY) and a trial phase (PURSUIT). A monitoring phase, the REMARRY study, aims to evaluate the dynamics of plasma RAS status during the subsequent treatments after refractory to anti-EGFR therapy in patients with mCRC with RAS/BRAF V600E wild-type tumors who have progressed after a response to previous anti-EGFR therapy, using a highly sensitive digital polymerase chain reaction OncoBEAM RAS CRC kit in a central laboratory (Sysmex, Japan). A trial phase, the PURSUIT trial, is a multicenter, single-arm phase II trial to assess the efficacy and safety of rechallenge therapy with panitumumab plus irinotecan in patients without RAS mutations in ctDNA (plasma RAS negative) in the REMARRY study. Key eligibility criteria of the PURSUIT trial include RAS/BRAF V600E wild-type mCRC in tumor tissue refractory or intolerant to fluoropyrimidine, oxaliplatin, and irinotecan; progression after complete or partial response to previous anti-EGFR therapy; plasma RAS negative (defined as plasma mutant allele frequencies [MAF] of all RAS ≤ 0.1%) within 28 days prior to enrollment; 4 months or more between the last administration of previous anti-EGFR mAb and the start of protocol treatment; and Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) ≤ 1. The primary endpoint is the confirmed objective response rate (ORR). The target sample size of the PURSUIT trial is 50 patients. Biomarker analyses will be performed in parallel using the OncoBEAM RAS CRC kit and a next-generation sequencing-based ctDNA analysis (Guardant360). DISCUSSION: Our trial aims to confirm the clinical benefit of anti-EGFR mAb rechallenge therapy in patients with plasma RAS negative. Moreover, through biomarker analyses, our trial will shed light on which patients would benefit from rechallenge in addition to being plasma RAS negative. TRIAL REGISTRATION: The REMARRY study: UMIN, UMIN000036424 . Registered date: April 5, 2019. The PURSUIT trial: jRCT, jRCTs031190096 . Registered date: October 1, 2019.

Infusion-related reaction to ramucirumab plus FOLFIRI in patients with advanced colorectal cancer.

BACKGROUND: An infusion-related reaction (IRR) is a well-known adverse event related to monoclonal antibodies, and antihistamine premedication is recommended to prevent IRRs. Ramucirumab plus FOLFIRI therapy is the standard second-line treatment for metastatic colorectal cancer (CRC). Ramucirumab is a fully human antibody, suggesting that the incidence of IRRs is lower, however, the current recommendation for the proper use of ramucirumab is antihistamine premedication, but the incidence and severity of ramucirumab-induced IRR without antihistamine premedication have not been elucidated. METHODS: A retrospective study to evaluate the incidence of ramucirumab-induced IRRs in unresectable CRC patients treated by ramucirumab plus FOLFIRI therapy. If the incidence of IRR without antihistamine premedication was not higher than that of cetuximab in a previous report (5.7%), planning a prospective study was considered. RESULTS: A total of 147 patients with unresectable CRC who had been treated by ramucirumab plus FOLFIRI therapy were identified. Of them, 106 (72%) patients received intravenous antihistamine premedication. An IRR occurred in 2 patients (1.4%), 1 grade 2 and 1 grade 3. They received antihistamine and steroid premedication. On the other hand, IRRs were not observed in 41 patients without antihistamine premedication, and the incidence of IRRs was significantly lower compared with the previous report of cetuximab (p < 0.001). CONCLUSION: The incidence of ramucirumab-induced IRRs without antihistamine premedication is low. Not using antihistamine premedication can decrease medical costs. These findings warrant further investigation in large-scale cohorts to clarify the incidence and severity of ramucirumab-induced IRRs and further clarify the proper use of ramucirumab.

Multicenter Cohort Study to Assess the Association between Changes on Imaging and Outcome after Regorafenib Treatment (KSCC1603).

BACKGROUND: Molecular targeted drugs having angiogenesis-inhibiting properties allow the induction of necrosis inside tumors. We retrospectively investigated the relationship between changes on imaging associated with regorafenib (REGO) and treatment outcomes using real-world data. PATIENTS AND METHODS: The eligibility criteria included an ECOG PS of 0-1, a starting dose of 120 or 160 mg/day of REGO, and a duration of treatment of at least 35 days. Regarding changes on imaging, cavitation in lung lesions (CLL), morphologic response of liver lesions (MRL), and change of liver metastasis density (CLD) were evaluated. RESULTS: We finally screened 671 cases, and 226 cases were eligible. In total, 172 and 145 patients had lung and liver metastases, respectively. Among the patients with lung metastasis, CLL was found in 69 patients (40.0%). The median progression-free survival (PFS) of the patients with and those without CLL was 3.2 and 2.4 months, respectively (hazard ratio [HR] = 0.758; 95% confidence interval [CI]: 0.529-1.087), and the median overall survival (OS) of these groups was 10.5 and 8.9 months, respectively (HR = 0.862; 95% CI: 0.579-1.285). MRL and CLD of liver metastasis were analyzed in 145 and 90 patients, respectively. The median OS with and without MRL was 8.9 and 8.2 months, respectively, whereas the median OS with and without CLD was 11.6 and 7.7 months, respectively (HR = 0.523; 95% CI: 0.275-0.992). CONCLUSION: CLL may predict PFS but not OS among patients with lung metastasis. CLD was predictive of favorable outcomes for REGO in patients with liver metastasis.

Impact of single-heterozygous UGT1A1 on the clinical outcomes of irinotecan monotherapy after fluoropyrimidine and platinum-based combination therapy for gastric cancer: a multicenter retrospective study.

BACKGROUND: It is unclear whether the UGT1A1 status, single heterozygous (SH) or wild type (WT), is associated with the efficacy and toxicity of irinotecan monotherapy in advanced gastric cancer (AGC). We investigated the association between clinical outcomes (efficacy and safety) and UGT1A1 status in patients who received irinotecan monotherapy. METHODS: We evaluated AGC patients who received irinotecan monotherapy between January 2011 and December 2017. Efficacy was assessed according to overall survival (OS) and progression-free survival (PFS). Toxicity was graded using the Common Toxicity Criteria for Adverse Events (version 4.0). RESULTS: A total of 100 patients were evaluated (62 and 38 patients with UGT1A1 WT and SH, respectively). In the WT and SH groups, the irinotecan dose was reduced in 19 (30.6%) and 18 (47.2%) patients (p = 0.135), respectively; treatment was delayed due to adverse events (AEs) in 19 (30.6%) and 13 (34.2%) patients (p = 0.826), respectively; the median PFS was 3.15 and 3.25 months (HR, 0.734; 95% CI 0.465-1.158; p = 0.184), respectively; and the median OS was 10.4 and 7.26 months (HR, 1.137; 95% CI 0.752-1.721; p = 0.543), respectively. Severe hematological AEs (Grade ≥ 3) were significantly more frequent in the SH group than in the WT group (63% vs. 36%; p = 0.008), while severe non-hematological AEs was not significantly different (16.0% vs. 6.5%; p = 0.173). CONCLUSION: There was no significant difference in the efficacy of irinotecan monotherapy between UGT1A1 WT and UGT1A1 SH, but UGT1A1 SH was associated with a high frequency of severe hematological toxicity.