Clinical verification of circulating tumor RNA (ctRNA) as novel pretreatment predictor and tool for quantitative monitoring of treatment response in metastatic colorectal cancer (mCRC): A biomarker study of the DEEPER trial

TPS3621

Background: A randomized phase II trial, DEEPER (JACCRO CC-13) [NCT02515734], is on-going to evaluate FOLFOXIRI plus cetuximab (cet) vs. FOLFOXIRI plus bevacizumab (bev) in terms of depth of response as primary endpoint in 360 mCRC patients (pts) with RAS wild-type tumors, PS0-1, and no previous chemotherapy. This is a head-to-head comparative trial of 2 key monoclonal antibodies in mCRC treatment; therefore, it would be of interest to perform the biomarker study for developing novel predictors of cet or bev. The clinical utility of circulating tumor DNA (ctDNA) analysis has been largely validated for monitoring during treatment and companion diagnostics after chemotherapy. However, there are few published results regarding ctRNA in cancer treatment. Use of ctRNA from liquid biopsies would enhance tumor profiling through the trending of actionable biomarkers not found in ctDNA, and allow for patient monitoring by measuring dynamic changes in levels of gene expressions. Methods: This study will enroll pts with willing to undergo biopsies of both tissue and blood among participants of the DEEPER trial. The estimated number is 250. The main purpose is to find novel predictors for efficacy of cet or bev in mCRC using liquid biopsies, which are performed to obtain ctDNA and ctRNA at 6 time points: pre-treatment, 8 weeks after treatment start, beginning of maintenance phase in FOLFOXIRI-regimen, progression, before and 8 weeks after 2nd-line treatment. The tissue samples collected before chemotherapy will be used for analyzing intra-tumoral genetic alterations. Associations between analytes in blood/tissue and the clinical outcomes of each treatment (with cet or bev) will be assessed using Fisher’s exact test, Kaplan-Meier curves, and log-rank tests in univariate analyses. We will evaluate on whether transcriptomic analysis in ctRNA could predict treatment efficacy more accurately compared to genomic analysis in ctDNA, and verify the clinical utility of ctRNA testing in mCRC treatment. Accrual will continue until the DEEPER trial is completed. Clinical trial information: UMIN000018412.

A Randomized Phase II Study of S-1 Adjuvant Chemotherapy With or Without Hochu-ekki-to, a Japanese Herbal Medicine, for Stage II/III Gastric Cancer: The KUGC07 (SHOT) Trial

Objectives: A multicenter randomized phase II study was conducted to evaluate the effects of Hochu-ekki-to (TJ-41) for reducing adverse reactions and increasing compliance with S-1 adjuvant therapy for advanced gastric cancer.

Methods: The eligibility criteria were pathological stage II/III after R0 resection. Patients received adjuvant therapy with S-1 alone (group S) or S-1 with TJ-41 (group ST) for 1 year. The primary endpoint was the completion rate of S-1. Secondary endpoints were adverse events, relative dose intensity, relapse-free survival (RFS), and overall survival (OS).

Results: We randomly assigned 56 patients to group ST and 57 patients to group S. The completion rates of S-1 were 54.5 and 50.9%, the median relative dose intensities were 89.2 and 71.9%, and adverse events of grade 3 or 4 occurred in 45.5 and 54.5% in groups ST and S, respectively. There was no significant difference in 3-year OS or RFS between the two groups.

Conclusions: TJ-41 does not increase relative dose and completion rate of S-1 significantly. J-41 may reduce toxic effects, but our findings do not support routine use of TJ-41 after gastrectomy.

[Rupture of Ovarian Metastasis from Cecal Cancer during Chemotherapy - A Case Report Suggestive of Bilateral Salpingo-Oophorectomy]

A 66-year-old woman was diagnosed with advanced cecal cancer with metastases to her right ovary, peritoneum, and liver. Ileocecal resection and right salpingo-oophorectomy were performed as cytoreduction surgery before systemic chemotherapy. The colon cancer metastasized to her left ovary during chemotherapy and grew rapidly until it ruptured spontaneously, although the other metastases sites continued to respond to treatment. Emergent left salpingo-oophorectomy was performed. Pathological findings confirmed ovarian metastasis from colon cancer. Ovarian metastases are less responsive to systemic chemotherapy compared to extra-ovarian metastasis and the rapid growth sometimes occurs as a related symptom. Bilateral salpingo-oophorectomy might be recommended in cytoreduction surgery even if the ovarian metastasis is unilateral.

Safety data from the phase III Japanese ACHIEVE trial: part of an international, prospective, planned pooled analysis of six phase III trials comparing 3 versus 6 months of oxaliplatin-based adjuvant chemotherapy for stage III colon cancer

Background

The International Duration Evaluation of Adjuvant chemotherapy project investigated whether a shorter duration of oxaliplatin-based adjuvant chemotherapy was as effective as 6 months of identical chemotherapy for resected stage III colon cancer. As part of this project, we report safety data from the Japanese ACHIEVE study (JFMC47-1202-C3).

Patients and methods

ACHIEVE was an open-label, multicentre trial randomising patients with stage III colon cancer to receive 3 m or 6 m of mFOLFOX6/CAPOX after surgery. Choice of regimen was declared before randomisation by a site investigator.

Results

Between August 2012 and June 2014, 1313 patients were enrolled and, of those, 1277 were analysed for the safety analysis, with 635 in arm 6 (mFOLFOX6, n=158; CAPOX, n=477) and 642 in arm 3 (mFOLFOX6, n=161; CAPOX, n=481). Grade 3 or worse peripheral sensory neuropathy (PSN) developed in 5%/0.6% of patients receiving mFOLFOX6 in arm 6/3 (p=0.019) and 6%/1% of those receiving CAPOX in arm 6/3 (p<0.001). Similarly, grade 2 or worse PSN developed in 36%/11% of patients receiving mFOLFOX6 in arm 6/3 (p<0.001) and 37%/14% of those receiving CAPOX in arm 6/3 (p<0.001). An association between baseline creatinine clearance (CCr) and adverse events (AEs) was found that patients with CAPOX were significantly more likely to develop AEs ≥grade 3 when they had a CCr ≤50 (OR 1.67; p=0.048).

Conclusions

We confirmed in the Japanese population that the shorter duration of adjuvant chemotherapy resulted in a significant reduction of PSN. In patients with CAPOX, renal function was significantly related to severe AEs.

Trial registration number

UMIN000008543, Results.

Age, gender, and performance status effects on efficacy of 3 versus 6 months of adjuvant oxaliplatin and fluoropyrimidine chemotherapy for stage III colon cancer: Phase III ACHIEVE trial as part of the IDEA collaboration

731

Background: ACHIEVE, a part of the IDEA collaboration, was a multicenter trial randomizing patients with stage III resected colon cancer to either 3 versus 6 months of mFOLFOX6/CAPOX. The primary endpoint was disease-free survival (DFS). We previously reported that the hazard ratios (HRs) of 3 versus 6 months duration in this study according to risk stage (low-risk [T1-3 and N1] or high-risk [T4 or N2]) and regimen (mFOLFOX6 or CAPOX) as well as in overall population were consistent with those observed in the whole IDEA. Methods: ACHIEVE enrolled 1313 patients in Japan between August 2012 and June 2014, out of whom 1291 pts were analyzed for efficacy analysis. As of June 2017, 291 DFS events were observed with a median follow-up time of 39 months. The HR of DFS in the overall population was 0.95 (0.76—1.20) with a 3-year DFS of 80% in 3 months arm and 78% in 6 months arm. In the current study, we investigated subgroup analyses for DFS including age, gender, and ECOG performance status (PS). Results: Outcomes of subgroup analyses are summarized in the Table. With regard to HRs and upper bound on the confidence intervals, the trend of 3 months arm being slightly inferior to 6 months arm in patients with an age of ≥70, female gender, and an ECOG PS of 1; however, there was no evidence of significant interaction across treatment duration and the subgroups. Conclusions: The treatment duration effect did not depend on age, gender, and ECOG PS. Further results according to risk stage and regimen will be presented. Clinical trial information: UMIN 000008543. [Table: see text]

A randomized phase II study of mFOLFOX6 plus bevacizumab versus mFOLFOX6 plus cetuximab for previously untreated, liver-limited metastatic colorectal cancer that is unsuitable for resection (ATOM trial)

734

Background: It is still a topic of ongoing debate as to which of the two agents, anti-VEGF antibody or anti-EGFR antibody, is more effective in patients with KRAS Exon 2 or RAS wild-type metastatic colorectal cancer (mCRC) in the first-line setting. ATOM is a multicenter, randomized trial comparing mFOLFOX6 plus bevacizumab (Bmab arm) with mFOLFOX6 plus cetuximab (Cmab arm) in patients with liver-limited metastases unsuitable for upfront resection. Methods: Patients with previously untreated mCRC were eligible if they had ≥5 liver-limited metastatic lesions and/or had liver-limited metastases with the maximum lesion diameter of > 5cm. Patients with KRAS Exon2-wild were registered but after Jan 2015 limited to those with all RAS-wild. Primary endpoint was progression-free survival (PFS), which was defined as the time from randomization to disease progression, recurrence after resection by surgery, or death from any cause (Central review). Key secondary endpoints included overall response rate (ORR), liver resection rate, and overall survival (OS). Results: A total of 122 pts were enrolled between May 2013 and April 2016. Of 116 eligible (59 in the Cmab arm and 57 in the Bmab arm), median age was 65/64 in the Cmab/Bmab arm; ECOG PS 0, 86/89%; all RAS wt, 98/95%; left-sided primary tumor, 76/84%. Efficacy results were summarized in the table. With a median follow-up of 24.3 months, the median PFS was 15.0 months in Cmab arm and 11.6 months in the Bmab arm with a hazard ratio of 0.803 (95%CI, 0.513–1.256), whereas ORR was 86% in the Cmab arm and 68% in the Bmab arm. Liver resection rate was 49% and 56% in the Cmab arm and the Bmab arm, respectively. Conclusions: In patients considered unsuitable for upfront resection of liver-limited metastasis, the two agents showed a similar efficacy. OS result will be presented elsewhere. Clinical trial information: NCT01836653. [Table: see text]

Metastatic colorectal cancer responsive to regorafenib for 2 years: a case report

BACKGROUND

Regorafenib is an oral multikinase inhibitor that has been demonstrated as clinically effective in patients with metastatic colorectal cancer in phase III studies. Although disease control was achieved in 40% of the pretreated patients with metastatic colorectal cancer in the pivotal studies, radiological response has rarely been reported. Severe adverse events associated with regorafenib are known to occur during the first and second courses of treatment. We present a case of a 62-year-old Japanese patient whose metastatic colorectal cancer has been responding to treatment with regorafenib for 2 years.

CASE PRESENTATION

A 54-year-old Japanese man visited our institute exhibiting general malaise, and he was diagnosed with ascending colon cancer in April 2006. He underwent right hemicolectomy, and the final staging was T3N0M0, stage II. After 19 months, pulmonary metastasis and anastomotic recurrences were detected, and a series of operations were performed to resect both metastatic lesions. After that, liver metastasis, a duodenal metastasis with right renal invasion, right adrenal metastasis, and para-aortic lymph node metastases were observed during follow-up, and chemotherapy and resection were performed. The patient had metastatic para-aortic lymph nodes after the fifth tumor resection and underwent multiple lines of chemotherapy in April 2014. Regorafenib monotherapy was started at 80 mg/day. Then, regorafenib was increased to 120 mg/day in the second cycle. Regorafenib monotherapy led to 60% tumor shrinkage within the initial 2 months, and the tumor further decreased in size over 4 months until it became unrecognizable on imaging studies. The clinical effects of regorafenib monotherapy have shown a partial response according to Response Evaluation Criteria in Solid Tumors criteria. No severe adverse events were observed, except for mild fatigue and hand-foot syndrome. The patient has received 24 courses of regorafenib over 2 years without exhibiting tumor progression.

CONCLUSIONS

To the best of our knowledge, this is the longest treatment with regorafenib without tumor progression ever reported. A reduced dosage of regorafenib at induction may ameliorate the cutaneous and hepatic toxicity associated with its use.

A Multicenter Phase 2 Study on the Feasibility and Efficacy of Neoadjuvant Chemotherapy Without Radiotherapy for Locally Advanced Rectal Cancer

BACKGROUND

This prospective multicenter phase 2 study aimed to evaluate the feasibility and efficacy of neoadjuvant chemotherapy (NAC) without radiotherapy for locally advanced rectal cancer (LARC).

METHODS

Patients with LARC (cStage II and III) were included in the study. Those with cT4b tumor were excluded. Six cycles of modified FOLFOX6 (mFOLFOX6) plus either bevacizumab or cetuximab, depending on KRAS status, were administered before surgery. The primary end point of the study was the R0 resection rate. The secondary end points were adverse effect, rate of NAC completion, postoperative complications, and pathologic complete response (pCR) rate.

RESULTS

The study enrolled 60 patients from eight institutions. For the study, mFOLFOX6 was administered with cetuximab to 40 patients who had wild-type KRAS and with bevacizumab to 20 patients who had KRAS mutations. The completion rate for NAC was 88.4%. Sphincter-preserving surgery was performed for 43 patients and abdominoperineal resection for 17 patients. The median operation time was 335 min, and the median blood loss was 40 g. The R0 resection rate was 98.3%, and the pCR rate was 16.7%. The overall postoperative complication rate (≥grade 2) was 21.7%. The complications included anastomotic leakage (11.6%), surgical-site infection (6.7%), and urinary dysfunction (3.3%). The patients with wild-type KRAS did not differ significantly from those with KRAS mutations in terms of response rate, postoperative complication rate, and pCR rate.

CONCLUSION

The findings show that NAC is a feasible and promising treatment option for LARC (This study is registered with UMIN-CTR, UMIN000005654).

Preventive Measures for Postoperative Bile Leakage After Central Hepatectomy: A Multicenter, Prospective, Observational Study of 101 Patients

BACKGROUND

There are no conclusive measures for preventing postoperative bile leakage (POBL).

METHODS

First, 310 patients who underwent hepatectomy were analyzed retrospectively to clarify risk factors for POBL. Then, focusing on operations at high risk of POBL, patients who underwent central hepatectomy were recruited prospectively among 18 institutions, to evaluate various preventive measures for avoiding POBL. The primary endpoint was the frequency of POBL.

RESULTS

The retrospective analysis revealed central hepatectomy and repeated hepatectomy to be independent risk factors for POBL. One hundred and one patients undergoing central hepatectomy were enrolled in the prospective study. POBL developed in 13 patients (12.9 %). Intraoperative bile leakage was recognized in 42 of the 101 patients (41.6 %), and 10 of the 42 patients developed POBL (23.8 %). Primary closure of the site of bile leakage and/or biliary drainage tube placement was preferable for preventing POBL in the patients with intraoperative bile leakage. Although 59 patients (58.4 %) did not show intraoperative bile leakage, three patients (5.1 %) developed POBL. In the group without intraoperative bile leakage, treatment with fibrin glue with a polyglycolic acid (PGA) sheet or collagen sheet coated with a fibrinogen and thrombin layer (CSFT) had good results.

CONCLUSIONS

Primary closure of the site of bile leakage and/or placement of biliary drainage tubes may be recommended in cases involving intraoperative bile leakage. Treatment with fibrin glue with a PGA sheet and/or CSFT might have preventive effects in patients without intraoperative bile leakage.

Baseline creatinine clearance as an indicator of severe adverse events associated with oxaliplatin-based adjuvant chemotherapy in patients with stage III colon cancer: Safety analysis of the phase III Japanese ACHIEVE trial

667

Background: The phase III ACHIEVE trial (JFMC47), a project of the International Duration Evaluation of Adjuvant Chemotherapy (IDEA), was established to prospectively analyze data from several randomized trials to test whether 3-month (arm 3) oxaliplatin-based adjuvant (FOLFOX4, mFOLFOX6, or XELOX) treatment is non-inferior to 6-month (arm 6) treatment in terms of disease-free survival in patients (pts) with stage III colon cancer. It aims to reveal the association between baseline characteristics and ≥ grade 3 adverse events (AEs) related to XELOX and mFOLFOX6, particularly focusing on the role of baseline creatinine clearance (CCr) on ≥ grade 3 AEs. Methods: This association was assessed using the Cox proportional hazards model. Results: During 2012–2014, 1,313 pts were randomized from 244 centers; 1,301 were included in the intention-to-treat population. Among the safety population (N = 1,277; 642, arm 3; 635, arm 6), the overall incidence of ≥ grade 3 AEs was 29% in arm 3 and 43% in arm 6 (p < 0.0001). Neuropathy of ≥ grade 2 was more frequent in arm 6 than in arm 3 (37% vs. 14%; p < 0.0001). Regarding the fluoropyrimidine backbone, grade 3–4 neutropenia was more with mFOLFOX6 than XELOX (30% vs. 12%), whereas grade 3–4 anorexia (2% vs. 5%) and grade 3–4 diarrhea (1% vs. 6%) were more with XELOX. Multivariate analysis, including treatment duration, regimen, CCr ( < 50 vs. > 50 mL/min), age, and sex, showed that CCr had a statistically significant impact on the occurrence of ≥ grade 3 AEs (hazard ratio = 0.44, p < 0.0001). Pts with CCr < 50 may have had more frequent ≥ grade 3 AEs independent of other factors, such as age. Conclusions: Grade 3 or higher AEs related to XELOX or mFOLFOX6 may be associated with the degree of CCr. Clinical trial information: UMIN 000008543.

Treatment outcome and recovery from peripheral sensory neuropathy during a 3-year follow-up in patients receiving modified FOLFOX6 as adjuvant treatment for stage II/III colon cancer (JFMC41-1001-C2: JOIN Trial)

703

Background: The JOIN Trial investigated safety and efficacy of modified FOLFOX6 (mFOLFOX6) in Japanese patients (pts) with stage II/III colon cancer. In the initial safety report, incidence of ≥ grade 3 (G3) peripheral sensory neuropathy (PSN) was 5.8% during treatment. Methods: Twelve cycles of mFOLFOX6 were given to pts with the following criteria: stage II/III curatively resected colon cancer; ECOG Performance Status (PS) of 0–1; age, ≥ 20 years; and adequate organ function. We report the treatment outcome results, including disease-free survival (DFS), relapse-free survival (RFS), overall survival (OS), and recovery from PSN during 3-year follow-up. Results: From November 2010 to March 2012, 882 pts were enrolled. In the efficacy group (N = 864; median follow-up, 3 years), pt characteristics were as follows: median age, 64 years; male, 53.8%; PS 0, 93.8%; stage II/IIIA/IIIB/IIIC (TNM), 18.5/7.3/52.5/21.6%; and lymph nodes examined, < 12/ > 12/unknown: 17.2/82.5/0.2%, respectively. Three-year DFS, RFS, and OS were 76.1, 77.3, and 92.7%, respectively. Favorable 3-year DFS, RFS, and OS were 92.1, 92.8, and 97.4% in stage II patients; 76.4, 77.9, and 93.8% in stage IIIA/B; and 61.6, 62.7, and 85.9% in stage IIIC, respectively. The main recurrent sites were liver (7.6%), lung (7.3%), and lymph nodes (5.2%). In multivariate Cox regression analysis, tumor histology, venous invasion, and lymph node metastatic ratio were statistically significant prognostic factors for DFS, RFS, and OS. Cumulative incidence of PSN during treatment was 47.8% in G1, 30.3% in G2, and 5.8% in G3. For those with G3 PSN during treatment, there was gradual recovery in 1.1% at 12 months after enrollment, 0.5% at 24 months, and 0.2% at 36 months. However, G1 and G2 residual PSN after 3 years was observed in 21.0% of pts (18.7%, G1; 2.3%, G2). Conclusions: Efficacy and safety of adjuvant mFOLFOX6 in pts with stage II/III colon cancer can be confirmed. Most pts successfully recovered from G3 PSN related to oxaliplatin, but G1 and G2 PSN was irreversible in one-fifth of pts at the 3-year follow-up. Clinical trial information: UMIN000004443.

Biliary architecture of livers exhibiting right-sided ligamentum teres: an indication for preoperative cholangiography prior to major hepatectomy

OBJECTIVE

To obtain information about the basic biliary anatomy of livers with right-sided ligamentum teres (RSLT).

SUMMARY OF BACKGROUND DATA

RSLT is a relatively rare anomaly with a reported incidence of 0.2-1.2%. Although the portal/hepatic venous and arterial anatomy of livers with RSLT has already been established, the biliary architecture of such livers remains unclear.

METHODS

RSLT was detected in 48 patients during 12,071 consecutive image readings (0.4%). Of these patients, the cholangiograms of 46 patients were analyzed, and their intrahepatic biliary tree confluence patterns were classified.

RESULTS

The following four unique biliary confluence patterns were identified in livers with RSLT: the symmetrical type (23/46), independent right lateral type (13/46), total left type (6/46), and total right type (1/46). Analyses of the portal and arterial branching patterns of these livers showed that there were no correlations between their biliary confluence patterns and their portal or arterial ramification patterns.

CONCLUSION

The basic biliary architecture of livers with RSLT was clarified. As the RSLT patients' anomalous biliary confluences differed from those seen in normal livers and were difficult to predict, preoperative cholangiography should be performed prior to complex hepatobiliary surgery involving livers with RSLT to ensure patient safety.

Large-scale prospective pharmacogenomics study of oxaliplatin-induced neuropathy in colon cancer patients enrolled in the JFMC41-1001-C2 (JOIN Trial)

BACKGROUND

Peripheral sensory neuropathy (PSN) is a dose-limiting toxicity of oxaliplatin-based chemotherapy. Several genetic markers have been shown to predict oxaliplatin-induced PSN; however, results remain to be validated in a large-scale and prospective pharmacogenomics study.

PATIENTS AND METHODS

Among 882 patients enrolled in the JFMC41-1001-C2 (JOIN trial), which was designed to investigate the tolerability of adjuvant-modified FOLFOX6 (mFOLFOX6) in Japanese Patients with stage II or III colon cancers undergoing curative resection, 465 patients were eligible for this pharmacogenomics analysis. Twelve single-nucleotide polymorphisms (SNPs) were selected based on published data. The effect of each genotype on time to PSN onset was evaluated in all patients (n = 465) using the Cox proportional hazard model. For the association analysis between severity of PSN and 12 SNP markers, 84 patients who failed to complete 12 cycles of mFOLFOX6 from grade 0/1 PSN group were excluded because the termination of the protocol treatment had been caused by reasons other than PSN.

RESULTS

Comparison of grade 0/1 PSN with grade 2/3 PSN or grade 3 PSN showed no significant associations with any of the 12 SNP markers after adjustment for total dose of oxaliplatin. Time-to-onset analysis also failed to reveal any significant differences.

CONCLUSIONS

Our large-scale and prospective pharmacogenomics study of Japanese patients receiving protocol treatment of adjuvant mFOLFOX6 could not verify a role for any of the 12 SNP markers reported as being significantly associated with PSN. Considering the OR observed in this study (range: 0.76-1.89), further evaluation of these 12 SNP markers in the context of L-OHP-induced PSN is unlikely to be clinically informative.