Impact of the perioperative assessment of deglutition on postoperative respiratory complications in elderly patients undergoing gastrectomy for gastric cancer.

PURPOSE: To investigate the association between perioperative deglutition screening and postoperative respiratory complications (PRCs) in elderly patients undergoing gastrectomy for gastric cancer. METHODS: We analyzed data from 86 patients with gastric cancer (aged ≥ 70 years) who underwent gastrectomy between October, 2016 and November, 2018. Videofluoroscopic swallowing examinations (VFSEs) were performed before and after surgery. We examined the association of these results with postoperative respiratory complications, as well as the relationships between demographic, operative, and swallowing function assessment data. RESULTS: PRCs were identified in 16 patients. The results of pre- and postoperative VFSE showed abnormalities in 28 and 32 patients, respectively. Multivariate analysis revealed that abnormalities in the postoperative VFSEs were strongly associated with the development of PRCs (P = 0.002). The findings of this analysis suggests that ventilatory impairment, a Charlson comorbidity index score ≥ 3, and an open surgical approach are independent risk factors for PRCs. CONCLUSION: This is the first study to demonstrate the efficacy of perioperative assessment of swallowing function using VFSE for predicting PRCs in elderly patients undergoing gastrectomy for gastric cancer.

Trifluridine/tipiracil+bevacizumab (BEV) vs. fluoropyrimidine-irinotecan+BEV as second-line therapy for metastatic colorectal cancer: a randomised noninferiority trial.

BACKGROUND: This open-label, multicentre, phase II/III trial assessed the noninferiority of trifluridine/tipiracil (FTD/TPI) plus bevacizumab vs. fluoropyrimidine and irinotecan plus bevacizumab (control) as second-line treatment for metastatic colorectal cancer (mCRC). METHODS: Patients were randomised (1:1) to receive FTD/TPI (35 mg/m2 twice daily, days 1-5 and days 8-12, 28-day cycle) plus bevacizumab (5 mg/kg, days 1 and 15) or control. The primary endpoint was overall survival (OS). The noninferiority margin of the hazard ratio (HR) was set to 1.33. RESULTS: Overall, 397 patients were enrolled. Baseline characteristics were similar between the groups. Median OS was 14.8 vs. 18.1 months (FTD/TPI plus bevacizumab vs. control; HR 1.38; 95% confidence interval [CI] 0.99-1.93; Pnoninferiority = 0.5920). In patients with a baseline sum of the diameter of target lesions of <60 mm (n = 216, post hoc analyses), the adjusted median OS was similar between groups (FTD/TPI plus bevacizumab vs. control, 21.4 vs. 20.7 months; HR 0.92; 95% CI 0.55-1.55). Grade ≥3 adverse events (FTD/TPI plus bevacizumab vs. control) included neutropenia (65.8% vs. 41.6%) and diarrhoea (1.5% vs. 7.1%). CONCLUSIONS: FTD/TPI plus bevacizumab did not demonstrate noninferiority to fluoropyrimidine and irinotecan plus bevacizumab as second-line treatment for mCRC. CLINICAL TRIAL REGISTRATION: JapicCTI-173618, jRCTs031180122.

The Phase II Study of Panitumumab in Chemotherapy-Naïve Frail or Elderly Patients with RAS Wild-type Colorectal Cancer: OGSG 1602 Final Results.

BACKGROUND: We previously reported the response rate of a phase II OGSG1602 study on panitumumab in chemotherapy-naive frail or elderly patients with RAS wild-type unresectable colorectal cancer (CRC) [Terazawa T, Kato T, Goto M, et al. Oncologist. 2021;26(1):17]. Herein, we report a survival analysis. METHODS: Patients aged ≥65 years and considered unsuitable for intensive chemotherapy or aged ≥76 years were enrolled. Primary tumors located from the cecum to the transverse colon were considered right-sided tumors (RSTs); those located from the splenic flexure to the rectum were considered left-sided tumors (LSTs). RESULTS: Among the 36 enrolled patients, 34 were included in the efficacy analysis, with 26 and 8 having LSTs and RSTs, respectively. The median progression-free survival (PFS) and overall survival (OS) were 6.0 [95% CI, 5.4-10.0] and 17.5 months (95% CI, 13.8-24.3), respectively. Although no significant differences existed in PFS between patients with LST and RST {6.6 (95% CI, 5.4-11.5) vs. 4.9 months [95% CI, 1.9-not available (NA), P = .120]}, there were significant differences in OS [19.3 (95% CI, 14.2-NA) vs.12.3 months (95% CI, 9.9-NA), P = .043]. CONCLUSION: Panitumumab showed favorable OS in frail or elderly patients with RAS wild-type CRC and no prior exposure to chemotherapy. Panitumumab may be optimal for patients with LSTs (UMIN Clinical Trials Registry Number UMIN000024528).

NEXUS trial: 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 colorectal oligometastases.

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.

Clinicopathological features of appendiceal goblet cell adenocarcinoma in Japan: a multicenter retrospective study.

PURPOSE: In the 5th edition of the World Health Organization classification, appendiceal goblet cell adenocarcinoma (GCA) is categorized separately from neuroendocrine tumors and other appendiceal adenocarcinomas. We clarified the clinicopathological characteristics of Japanese appendiceal GCA. METHODS: We designed a retrospective multicenter cohort study and retrieved the data of patients with appendiceal neoplasms and histologically diagnosed appendiceal goblet cell carcinoid (GCC) treated from January 2000 to December 2017 in Japan. The available GCC slides were reviewed and diagnosed with a new grading system of GCA. RESULTS: A total of 922 patients from 43 institutions were enrolled; of these, 32 cases were patients with GCC (3.5%), and 20 cases were ultimately analyzed. The 5-year survival rate was 61.4% (95% confidence interval: 27.4-83.2), and the median survival time was 93.1 months. For peritoneal metastasis, regional lymph node metastasis was a significant factor (p = 0.04), and Grade 3 was a potential factor (p = 0.07). No peritoneal metastasis was observed in either T1/2 patients (n = 2) or Grade 1 patients (n = 4). We were unable to detect any significant factors associated with regional lymph node metastasis. CONCLUSION: For peritoneal metastasis, regional lymph node metastasis was a significant factor, and Grade 3 was a potential factor.

[A Case of Hepatic Encephalopathy Caused by Portal Vein Thrombosis after Surgery for Perihilar Cholangiocarcinoma].

A female in her 70s underwent right hepatectomy with resection of caudate lobe and extrahepatic bile duct for perihilar cholangiocarcinoma(T2aN0M0, Stage Ⅱ: Biliary Cancer Treatment Regulations, 7th edition). On the 4th postoperative day, the patient had impaired consciousness, which worsened to almost coma on the 5th postoperative day. On the same day, a blood test showed high ammonia level, thus the state was thought to be hepatic encephalopathy. Contrast -enhanced CT on the same day showed thrombus from the main trunk of the portal vein to the remnant left branch, narrowing of the lumen of the vessel. Simultaneously, enlarged portosystemic shunt in the pelvic floor due to portal hypertension induced by the thrombosis. Plasmapheresis was performed, and anticoagulation with sodium heparin and antithrombin Ⅲ were started. Then, the portal vein thrombus was reduced, and encephalopathy was improved. She was discharged from the hospital on postoperative day 48. She was treated with edoxaban as an outpatient, and anticoagulation therapy was terminated after a CT scan 6 months after surgery, which confirmed no recurrence of thrombus. She is now alive without recurrence of thrombus or tumor for about 2 years after the surgery.

[A Case of Rectal Cancer in Which Total Pelvic Organ Excision Could Be Avoided by TNT Therapy and Robotic Surgery].

The patient is a 50s year old man. He visited his local doctor with complaints of anal pain and bloody stools, and a rectal examination revealed a tumor on the anterior wall of the rectal canal. CT imaging showed tumors invading the prostate, urethra, and anorectal muscles, and a 3 mm-sized nodule was found in the lungs. The patient was diagnosed as cT4bN1M1a, Stage Ⅳ, and total neoadjuvant chemotherapy was planned as preoperative treatment. The 5 Gy×5 times radiation therapy followed by 5 courses of CAPOX plus BEV as preoperative chemotherapy and CAPOX. CAPOX was administered. After completion of treatment, the colonoscopy showed PR, and MRI showed clear boundary between the prostate and tumor but invasion into the anorectal muscles; CT showed no lung metastasis, and preoperative diagnosis was ycT4bN0M0, ycStage Ⅱ. Robotic-assisted rectal amputation and left lateral lymph node dissection were performed under general anesthesia. Pathologically, the patient was diagnosed as ycT4bN0M0, Stage Ⅱ, and the efficacy was determined as TRG 1(AJCC). Vertical dissection was negative and radical resection was possible.

[A Case of Locally Advanced Sigmoid Colon Cancer Invading the Urinary Bladder Treated with Neoadjuvant Chemotherapy and Robot Assisted Urinary Bladder-Conserving Surgery].

We report a case of 72s male with locally advanced sigmoid colon cancer. Colonoscopy revealed an advanced sigmoid colon cancer(AV 15 cm, type 2, semi-peripheral, deeper than T3). He was diagnosed as cT4bN2M0, cStage Ⅲc(Japanese Classification of Colorectal, appendiceal, and, Carcinoma, 9th edition), and was given chemotherapy as preoperative treatment. He was treated with CAPOX plus BEV as neoadjuvant chemotherapy. Preoperative diagnosis was ycT4bN0M0, ycStage Ⅱc. The robot assisted high anterior resection and partial bladder resection were performed. The bladder was sutured under robotic assistance. The residual bladder capacity was 100 mL. Postoperative diagnosis was ypT0N0M0, ypStage 0, TRG 0 (AJCC). We experienced a case of neoadjuvant chemotherapy for rectosigmoid colon cancer with bladder invasion, which resulted in pCR.

[A Case of Single Hole Ileal Resection for Ascendiry Colon Cancer with Ureterocutaneous Fistula in the Right Lower Abdomen].

The patient is a 70s woman. She underwent cystectomy for bladder cancer 6 years ago and had a ureterocutaneous fistula in the right lower abdomen. After colonoscopy for positive fecal occult blood, a type 1 elevated lesion was found in the ascending colon, which was diagnosed as a well-differentiated adenocarcinoma on biopsy. Surgery was performed with a single hole. The approach from the right lower abdomen, where the ureterocutaneous fistula and ureter are located, was avoided, and the approach from the hepatic flexure of the transverse colon was used first. After the right colon was mobilized, the large mesh adhesions around the ureter were carefully dissected, and the right ureter was identified and preserved, extending from the lateral ascending colon to the abdominal wall. The ileal artery was dissected at the root and after dissection of the D3 lymph node, the intestine was dissected and anastomosed extracorporeally. The operative time was 246 minutes with small amount of blood loss. The patient was discharged on the 6th postoperative day without any postoperative complications. The pathology result was pT3N0M0, pStage Ⅱa, and radical resection had been performed. The patient is currently undergoing recurrence-free follow-up.

[A Case of Pathological Complete Response for MSI-High Locally Advanced Unresectable Transverse Colon Cancer Treated with Nivolumab plus Ipilimumab Combination Therapy].

74-year-old woman was diagnosed with locally advanced unresectable transverse colon cancer. She started CAPOX therapy as first-line therapy after ileostomy. After second course, MSI-high was detected, so nivolumab plus ipilimumab combination therapy was started as second-line therapy. After 4 courses of combination therapy, she was judged to be in partial response and surgery was performed. Histopathological diagnosis of the surgical specimen showed complete response, and she is still alive without recurrence 15 months after surgery.

[A Case of Response to Pembrolizmab in Unresectable MSI-High Transverse Colon Cancer].

A 80s man was diagnosed circulated type 2 colon cancer at the transverse colon, and pathological findings was adenocarcinoma( por1). Genomic findings were microsatellite instability-high(MSI-H), all RAS wild type and BRAFV600E mutated. Contrast-enhanced CT showed an enlarged lymph nodes(#221, #222, #223, #214)along the middle colic and superior mesenteric artery. Clinical diagnosis was a locally advanced unresectable transverse colon cancer, cT4aN3M1a(LYM), cStage Ⅳa. Drug therapy with pembrolizumab was prescribed. Six months later, contrast-enhanced CT and PET demonstrated remarkable shrinkage of the primary tumor and lymph nodes except 2 peri-colic enlarged lymph nodes. Primary lesion turned almost undetectable, however the biopsy demonstrated residual tumor. Two months later, CT showed that the residual lymph nodes had also disappeared.

[A Case of Conversion Surgery after Chemotherapy for Locally Advanced Unresectable Rectal Cancer].

We report a case of locally advanced rectal cancer that could not be curatively resected, in which the patient underwent conversion surgery after chemotherapy. The patient is a 70-year-old woman. She came to our hospital with a chief complaint of lower abdominal pain, and a close examination revealed rectal cancer with invasion of the external iliac artery and pelvic wall. She was treated with mFOLFOX6 plus cetuximab for locally advanced rectal cancer that was not amenable to surgical resection. After 11 courses of chemotherapy, significant shrinkage of the tumor was observed, and robot assisted laparoscopic high-anterior resection was performed. The patient didn't relapse at 12 months after surgery without adjuvant chemotherapy.

Multicenter, single-arm, phase II study of the continuous use of panitumumab in combination with FOLFIRI after FOLFOX for RAS wild-type metastatic colorectal cancer: Exploratory sequential examination of acquired mutations in circulating cell-free DNA.

This multicenter single-arm, phase II study evaluated the efficacy and safety of uninterrupted panitumumab usage combined with cytotoxic doublets for unresectable/metastatic colorectal cancer (mCRC). Additionally, clinical value of the RAS/BRAF mutation status in circulating cell-free DNA (ccfDNA) was evaluated; this evaluation was measured independently of the protocol treatment. Eligible patients with RAS wild-type mCRC who had received the first-line panitumumab plus FOLFOX treatment were recruited and administered continuous panitumumab combined with FOLFIRI. Progression-free survival (PFS) at 6 months was the primary endpoint, with threshold and expected values of 35% and 50%, respectively. In total, 54 patients were enrolled between October 2017 and October 2019. The crude 6-month PFS rate was 37.0%, with a 4.8-month median PFS. The response rate and disease control rate were 16.7% and 50.0%, respectively. Notably, of the 54 participants, 17 showed RAS/BRAF mutations until the end of the protocol treatment and of the 22 patients with progressive disease as their best response, 10 possessed RAS/BRAF mutations in their plasma ccfDNA at baseline. The median PFS significantly differed among patients harboring tumors with BRAF and RAS mutations and those with wild-type tumors. In conclusion, our study failed to show the expected efficacy of the continuous panitumumab use in the second-line treatment. Liquid biopsy discriminated the duration of PFS according to the mutation status. The effectiveness of continuous treatment with panitumumab should be evaluated in patients with RAS/BRAF wild-type mCRC determined by liquid biopsy at the start of the second-line treatment.

Impact of early tumor shrinkage on quality of life in patients treated with first-line cetuximab plus chemotherapy for unresectable metastatic colorectal cancer: results of Phase II QUACK trial.

PURPOSE: Although early tumor shrinkage (ETS) is a predictor of improved overall survival (OS), the association between ETS and health-related quality of life (HRQOL) remains unclear for patients with metastatic colorectal cancer (mCRC) treated with first-line cetuximab plus chemotherapy. METHODS: The data were collected from a prospective trial that assessed HRQOL using the EORTC QLQ-C30. The impact of ETS on HRQOL was estimated using a linear mixed-effects model for repeated measures. RESULTS: ETS was achieved in 82 (64.1%) of 128 mCRC patients treated with first-line cetuximab plus chemotherapy, and these patients had a significantly longer OS than those without ETS (HR, 0.38; 95% CI, 0.20-0.72; P = .002). Asymptomatic patients with ETS had a favorable OS, while symptomatic patients without ETS had a worse OS (2-year OS rates, 77.8% vs. 42.5%). Symptomatic patients with ETS had similar outcomes as asymptomatic patients without ETS (2-year OS rates, 64.1% vs. 67.0%). For symptomatic patients, ETS was associated with improved HRQOL scores between baseline and 8 weeks: the mean changes for patients with and without ETS were 5.86 and -4.94 for global health status (GHS)/QOL, 26.73 and 3.79 for physical functioning, and 13.58 and -3.10 for social functioning, respectively. The improved HRQOL was comparable to that of asymptomatic patients without ETS. For asymptomatic patients, ETS showed a decreased deterioration in HRQOL. CONCLUSION: Our findings highlight the importance of ETS for HRQOL and prognostic estimates, and assessing ETS may provide clinically useful information for physicians and patients to make more informed decisions.

TRESBIEN (OGSG 2101): encorafenib, binimetinib and cetuximab for early recurrent stage II/III BRAF V600E-mutated colorectal cancer.

The BRAF V600E mutation accounts for approximately 5% of colorectal cancer (CRC) cases and is an extremely poor prognostic factor. However, there are no clear recommendations regarding first-line therapy for patients with early recurrent BRAF V600E-mutated CRC, during or after adjuvant chemotherapy. Recently, a novel combination of encorafenib, binimetinib and cetuximab, showed a higher response rate than standard chemotherapy in patients with BRAF V600E-mutated CRC. Here we describe our plan for the TRESBIEN study (OGSG 2101), which is an open-label, multicenter, single-arm, phase II study designed to evaluate whether encorafenib, binimetinib and cetuximab are effective for patients with early recurrent BRAF V600E-mutated colorectal cancer, during or after adjuvant chemotherapy. The planned number of subjects is 25.

An ongoing study to evaluate encorafenib, binimetinib and cetuximab for people with early recurrent BRAF V600E-mutated colorectal cancer. BRAF V600E-mutated colorectal cancer (CRC) is a type of cancer caused by change (mutation) in a gene called BRAF. It is one of the most difficult types of CRC to treat because currently available drugs do not effectively treat the disease. Recently, two novel treatments, encorafenib and cetuximab, have been approved for use together in several countries for the treatment of advanced or metastatic BRAF V600E-mutated CRC. In Japan, these drugs are also approved to be given with another treatment called binimetinib, an approach called triplet therapy. This article describes the ongoing TRESBIEN study that is looking at how effective and how safe triplet therapy is for the treatment of people with early recurrent BRAF V600E-mutated CRC, during or after they have additional (adjuvant) chemotherapy. This study is ongoing, and the researchers are currently recruiting new participants. TRESBIEN will evaluate the percentage of participants whose tumors shrink with triplet therapy. The study will also look at any side effects. Clinical Trial Registration: jRCTs051210152 (ClinicalTrials.gov) (Japan Registry of Clinical Trials https://jrct.niph.go.jp/search?language=en&page=1).

Short- and Long-Term Outcomes of Single-Incision Laparoscopic Surgery for Right-Side Colon Cancer.

INTRODUCTION: There are little data concerning the long-term outcome of single-incision laparoscopic surgery (SILS) for colon cancer. Therefore, we investigated not only the short-term outcomes but also the long-term outcomes of SILS for right-side colon cancer. METHODS: We retrospectively compared short- and long-term outcomes of SILS and conventional laparoscopic surgery (CLS) for right-sided colon cancer in our institution. Intergroup differences of short-term outcomes were evaluated using χ2 or Fisher exact tests and 2-sample Student t tests. The disease-free survival rates (long-term outcome) of stage II and III patients were estimated using the Kaplan-Meier method and compared using log-rank tests. RESULTS: There were 290 operations conducted for right-side (cecum and ascending) colorectal cancers from April 2011 to July 2018. Open surgery was performed in 12 cases from start to the operation. SILS was performed in 196 cases and CLS in 55 cases. One patient underwent intraoperative conversion from SILS to laparotomy for bleeding control. In addition, 1 port was added to SILS in 3 cases. These 4 cases were included in the analysis as the SILS group according to the principle of intent to treat. BACKGROUND: Factors including age, gender, body mass index, performance status, and tumor stage were not statistically different between the SILS and CLS groups. In short-term outcomes, the number of harvested lymph nodes was not statistically different. SILS required less operating time (p < 0.001) and resulted in a reduced bleeding volume (p < 0.001). There was no statistical difference in the frequency of overall complications (p = 0.06). The disease-free survival of stage II and III patients was not statistically different between the 2 groups. CONCLUSIONS: With the proper adaptation of SILS by an experienced surgeon, the short- and long-term outcomes of SILS were not inferior to those of CLS. Therefore, SILS could be a treatment option for right-sided colon cancer.

[A Case of Metastatic Liver Tumor from Colon Cancer with Preoperative Diagnosis Obtained by Immunohistochemical Analysis of Cytologic Specimen].

CASE: A woman in her 50s underwent sigmoid colectomy and D3 lymph node dissection for sigmoid cancer(pT3, N0, M0, Stage Ⅱ: Japanese Classification of Colorectal, Appendiceal, and Anal Carcinoma 9th). She received adjuvant chemotherapy with capecitabine. Seven months after surgery, contrast-enhanced computed tomography( CECT) scan revealed a small mass in the segment 2 (S2) of the liver with dilation of peripheral intrahepatic bile duct, and the size of this mass and the bile duct dilatation were gradually increased. FDG positron emission tomography(FDG-PET)/CT showed abnormal FDG uptakes in the lesion of S2, and EOB-MRI detected other small lesions in the S6 and S7. Considering the results of image examinations, multiple lesions intrahepatic cholangiocarcinoma was firstly assumed. However, immunohistochemistry of the tumor obtained by endoscopic retrograde cholangiopancreatography (ERCP) showed cytokeratin 7-negative. Based on preoperative diagnosis of liver metastasis from colon cancer rather than intrahepatic cholangiocarcinoma, we performed left lobectomy, partial hepatectomy of S6 and S7 and cholecystectomy. In the resected specimen, the tumor was macroscopically located in the intrahepatic bile ducts. Microscopically, there existed atypical epithelial cells with glandular duct-like structure, and the lesions was histopathologically diagnosed as metastasis from colon cancer. She was discharged on the 10th postoperative day, and she is alive without recurrence one year after surgery.

[Investigation of the Short-Term Outcome of Perioperative Heparinization in Laparoscopic Surgery for Colorectal Cancer].

In aging society, the number of colorectal cancer patients who take antithrombotic drugs is increasing. However, there are not established guidelines for perioperative management for antithrombotic drugs in laparoscopic surgery. Here, we investigated the clinical outcomes of antithrombotic drugs withdrawal and perioperative heparinization in laparoscopic surgery for colorectal cancer patients taking antithrombotic drugs. From January 2015 to December 2017 in our center, patients who took antithrombotic drugs and underwent laparoscopic surgery for colorectal cancer were reviewed retrospectively. The association between postoperative complications and heparinizations was analyzed. Among 79 patients taking antithrombotic drugs, heparinization was performed in 40 patients(50.6%). The total length of hospital stay in heparinization group was 21 days and significantly longer than 13 days in the non-heparinization group. There were no significant differences in the operation time, intraoperative blood loss, and postoperative complications between the 2 groups. The antithrombotic drugs withdrawal and perioperative heparinization were suggested to be safe and feasible in laparoscopic surgery for patients with colorectal cancer.

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.

Phase II Study of Panitumumab Monotherapy in Chemotherapy-Naïve Frail or Elderly Patients with Unresectable RAS Wild-Type Colorectal Cancer: OGSG 1602.

LESSONS LEARNED: Panitumumab monotherapy showed favorable efficacy and feasibility in the treatment of frail or elderly patients with RAS wild-type unresectable colorectal cancer. It is especially effective for left-sided tumors; therefore, panitumumab as first-line treatment could be an additional therapeutic option for frail elderly patients, particularly in those who are unsuitable for upfront oxaliplatin-based or irinotecan-based combination regimens. BACKGROUND: First-line panitumumab monotherapy is expected to be well tolerated and improve survival in patients ineligible for intensive chemotherapy. However, its safety and efficacy in chemotherapy-naïve frail or elderly patients with unresectable RAS wild-type (WT) colorectal cancer (CRC) have not been studied. The aim of this phase II trial was to evaluate the efficacy and safety of panitumumab as first-line treatment. METHODS: We conducted a multicenter phase II study on patients aged ≥76 years or ≥65 years considered unsuitable for intensive chemotherapy. Panitumumab 6 mg/kg of intravenous infusion was administered every 2 weeks. The primary endpoint was disease control rate (DCR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), response rate (RR), time to treatment failure (TTF), and incidence of grade 3 or 4 toxicities. RESULTS: Thirty-six patients (median age: 81 [range, 67-88] years) were enrolled between February 2017 and August 2018. Two patients were excluded from the analysis of efficacy: one from lack of image examination at baseline and the other from lack of a measurable lesion. Thirty-three (91.6%) patients had a performance status (PS) of 0 or 1, whereas two (5.6%) patients and one (2.8%) patient had a PS of 2 and 3, respectively. Twenty-eight patients (77.8%) had left-sided CRC, whereas eight (22.2%) had right-sided CRC. The RR was 50.0% (95% confidence interval [CI], 32.4-67.6), including three patients (8.8%) who had complete responses. A total of 26.5% had stable diseases, resulting in a DCR of 76.5% (90% CI, 61.5-87.7). The RR of patients with left- and right-sided tumors was 65.4% (95% CI, 44.3-82.8) and 0.0% (95% CI, 0.0-36.9), respectively. Major grade 3 or 4 nonhematologic toxicities were rash (n = 6, 16.7%), hypomagnesemia (n = 4, 11.1%), fatigue (n = 3, 8.3%), paronychia (n = 2, 5.6%), and hyponatremia (n = 2, 5.6%). The only grade 3 hematologic toxicity was neutropenia (n = 1, 2.8%). CONCLUSION: Panitumumab monotherapy showed favorable efficacy and feasibility in frail or elderly patients with RAS WT unresectable CRC. Survival analysis including OS, PFS, and TTF is currently in progress.