Non-operative management after chemoradiotherapy plus consolidation or sandwich (induction with bevacizumab and consolidation) chemotherapy in patients with locally advanced rectal cancer: a multicentre, randomised phase II trial (NOMINATE trial).

INTRODUCTION: Total mesorectal excision (TME) and postoperative adjuvant chemotherapy following neoadjuvant chemoradiotherapy (CRT) is the standard treatment for locally advanced rectal cancer (LARC). However, neoadjuvant CRT has no recognised impact on reducing distant recurrence, and patients suffer from a long-lasting impairment in quality of life (QOL) associated with TME. Total neoadjuvant therapy (TNT) is an alternative approach that could reduce distant metastases and increase the proportion of patients who could safely undergo non-operative management (NOM). This study is designed to compare two TNT regimens in the context of NOM for selecting a more optimal regimen for patients with LARC. METHODS AND ANALYSIS: NOMINATE trial is a prospective, multicentre, randomised phase II selection design study. Patients must have clinical stage II or III (T3-T4Nany) LARC with distal location (≤5 cm from the anal verge or for those who are candidates for abdominoperineal resection or intersphincteric resection). Patients will be randomised to either arm A consisting of CRT (50.4 Gy with capecitabine) followed by consolidation chemotherapy (six cycles of CapeOx), or arm B consisting of induction chemotherapy (three cycles of CapeOx plus bevacizumab) followed by CRT and consolidation chemotherapy (three cycles of CapeOx). In the case of clinical complete response (cCR) or near cCR, patients will progress to NOM. Response assessment involves a combination of digital rectal examination, endoscopy and MRI. The primary endpoint is the proportion of patients achieving pathological CR or cCR≥2 years, defined as the absence of local regrowth within 2 years after the start of NOM among eligible patients. Secondary endpoints include the cCR rate, near cCR rate, rate of NOM, overall survival, distant metastasis-free survival, locoregional failure-free survival, time to disease-related treatment failure, TME-free survival, permanent stoma-free survival, safety of the treatment, completion rate of the treatment and QOL. Allowing for a drop-out rate of 10%, 66 patients (33 per arm) from five institutions will be accrued. ETHICS AND DISSEMINATION: The study protocol was approved by Wakayama Medical University Certified Review Board in December 2020. Trial results will be published in peer-reviewed international journals and on the jRCT website. TRIAL REGISTRATION NUMBER: jRCTs051200121.

Treatment sequences of patients with advanced colorectal cancer and use of second-line FOLFIRI with antiangiogenic drugs in Japan: A retrospective observational study using an administrative database.

The objectives were to describe treatment sequences for advanced colorectal cancer (CRC), use of second-line FOLFIRI (leucovorin, 5-fluorouracil, irinotecan) plus antiangiogenic drug (bevacizumab, ramucirumab, aflibercept beta) therapy, and the factors associated with the duration of antitumor drug treatment from second-line antiangiogenic therapy in Japan. This retrospective observational study was conducted using a Japanese hospital-based administrative database. Patients were enrolled if they started adjuvant therapy (and presumably experienced early recurrence) or first-line treatment for advanced CRC between May 2016 and July 2019, and were analysed until September 2019. Factors associated with overall treatment duration from second-line treatment with FOLFIRI plus antiangiogenic drugs were explored with multivariate Cox regression analysis. The most common first-line treatments were FOLFOX (leucovorin, 5-fluorouracil, oxaliplatin) or CAPOX (capecitabine, oxaliplatin) with bevacizumab (presumed RAS-mutant CRC) and FOLFOX with panitumumab (presumed RAS-wild type CRC). The most common second-line treatments were FOLFIRI-based. Many patients did not transition to subsequent lines of therapy. For second-line treatment, antiangiogenic drugs were prescribed more often for patients with presumed RAS-mutant CRC, right-sided CRC, and independent activities of daily living (ADL). The median duration of second-line FOLFIRI plus antiangiogenic drug treatment was 4.5 months; 66.2% of patients transitioned to third-line therapy. Low body mass index and not fully independent ADL were significantly associated with shorter overall duration of antitumor drug treatment from second-line therapy. Left-sided CRC, presumed RAS-wild type CRC, previous use of oral fluoropyrimidines and use of proteinuria qualitative tests, antihypertensives, or anticholinergics during second-line therapy were significantly associated with longer treatment. Treatment of advanced CRC in Japan is consistent with both international and Japanese guidelines, but transition rates to subsequent therapies need improvement. In addition to antitumor drug treatment, better ADL, higher body mass index, management of hypertension, and proteinuria tests were associated with continuation of sequential therapy that included antiangiogenic drugs.

Histopathological factors affecting the extraction of high quality genomic DNA from tissue sections for next-generation sequencing.

To enable the widespread application of genomic medicine, the extraction of genomic DNA from thin sections of archived formalin-fixed and paraffin-embedded (FFPE) tissue blocks for next-generation sequencing (NGS) is often necessary. However, there are currently no guidelines available on which specific regions of the microtome sections to use for macrodissection with respect to the histopathological factors observed under microscopic examination. The aim of this study was to clarify the relationship between histopathological factors and DNA quality, and to standardize the macrodissection method for more efficient implementation of NGS. FFPE tissue specimens of 218 patients from the Biomarker Research for Anti-EGFR Monoclonal Antibodies by Comprehensive Cancer Genomics study were used to investigate the relationship between 15 histopathological factors and the quantitative ratio of double-stranded DNA (dsDNA) to total nucleic acids, as well as the ∆ crossing point value of each tissue specimen. Multivariate logistic regression analysis revealed that specimen storage of ≥3 years was negatively associated with dsDNA quality (P=0.0007, OR: 4.30, 95% CI: 1.85-10.04). In contrast, the presence of a mucus pool was positively associated with dsDNA quality (P=0.0308, OR: 0.23, 95% CI: 0.06-0.87). Metastatic tumors and longer specimen storage periods were significantly associated with lower ∆Cp values (P=0.0007, OR: 4.43, 95% CI: 1.87-10.49; and P=0.0003, OR: 5.51, 95% CI: 2.18-13.95, respectively). Therefore, macrodissection should not be performed on specimens exhibiting histopathological factors associated with poor DNA quality. In particular, the use of tissue blocks with a storage period of <3 years allows the extraction of genomic DNA suitable for NGS.

Phase II Trial of Neoadjuvant Chemotherapy, Chemoradiotherapy, and Laparoscopic Surgery with Selective Lateral Node Dissection for Poor-Risk Low Rectal Cancer.

PURPOSE: The aim of this study is to evaluate the safety and efficacy of induction modified 5-fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) plus bevacizumab followed by S- 1-based chemoradiotherapy in magnetic resonance imaging (MRI)-defined poor-risk locally advanced low rectal cancer. PATIENTS AND METHODS: This was a prospective phase II trial at a single comprehensive cancer center. The primary endpoint was the pathological complete response (pCR) rate. Eligible patients had clinical stage II-III low rectal adenocarcinoma with any of the following MRI-defined poor-risk features: circumferential resection margin (CRM) ≤ 1 mm, cT4, positive lateral nodes, mesorectal N2 disease, and/or requiring abdominoperineal resection. Patients received six cycles of mFOLFOX6 with 5 mg/kg bevacizumab followed by oral S-1 (80 mg/m2/day on days 1-14 and 22-35) plus radiotherapy (50.4 Gy). Surgery was conducted through a laparoscopic approach. Lateral node dissection was selectively added when the patient had enlarged lateral nodes. RESULTS: A total of 43 patients were enrolled. Grade 3-4 adverse events occurred in nine patients during induction chemotherapy and in five patients during chemoradiotherapy. One patient declined surgery with a clinical complete response. Forty-two patients underwent surgery, and 16 had pCR [37.2%, 95% confidence interval (CI) 24.4-52.1%]. All underwent R0 resection without conversion, including combined resection of adjacent structures (n = 14) and lateral node dissection (n = 30). Clavien-Dindo grade 3-4 complications occurred in six patients (14.3%). With median follow-up of 52 months, six developed recurrences (lung n = 5, local n = 1; 3-year relapse-free survival 86.0%). CONCLUSIONS: This study achieved a high pCR rate with favorable toxicity and postoperative complications in poor-risk locally advanced low rectal cancer. Multicenter study is warranted to evaluate this regimen.

Clinical significance of BRAF non-V600E mutations on the therapeutic effects of anti-EGFR monoclonal antibody treatment in patients with pretreated metastatic colorectal cancer: the Biomarker Research for anti-EGFR monoclonal Antibodies by Comprehensive Cancer genomics (BREAC) study.

BACKGROUND: Patients with BRAFV600E-mutated metastatic colorectal cancer (mCRC) have a poorer prognosis as well as resistance to anti-EGFR antibodies. However, it is unclear whether BRAF mutations other than BRAFV600E (BRAFnon-V600E mutations) contribute to anti-EGFR antibody resistance. METHODS: This study was composed of exploratory and inference cohorts. Candidate biomarkers identified by whole exome sequencing from super-responders and nonresponders in the exploratory cohort were validated by targeted resequencing for patients who received anti-EGFR antibody in the inference cohort. RESULTS: In the exploratory cohort, 31 candidate biomarkers, including KRAS/NRAS/BRAF mutations, were identified. Targeted resequencing of 150 patients in the inference cohort revealed 40 patients with RAS (26.7%), 9 patients with BRAFV600E (6.0%), and 7 patients with BRAFnon-V600E mutations (4.7%), respectively. The response rates in RAS, BRAFV600E, and BRAFnon-V600E were lower than those in RAS/BRAF wild-type (2.5%, 0%, and 0% vs 31.9%). The median PFS in BRAFnon-V600E mutations was 2.4 months, similar to that in RAS or BRAFV600E mutations (2.1 and 1.6 months) but significantly worse than that in wild-type RAS/BRAF (5.9 months). CONCLUSIONS: Although BRAFnon-V600E mutations identified were a rare and unestablished molecular subtype, certain BRAFnon-V600E mutations might contribute to a lesser benefit of anti-EGFR monoclonal antibody treatment.

How do we apply adjuvant FOLFOX to Japanese patients with curatively resected colorectal cancer?

AIM: In Japan the combination of fluorouracil (5-FU), leucovorin and oxaliplatin (FOLFOX) was approved as adjuvant therapy for stage III or high-risk stage II colon cancer only in September 2009. In this study we evaluated the safety and efficacy of FOLFOX as adjuvant chemotherapy for stage IIIb or IV colorectal cancer (CRC) patients in a Japanese group at a single institute. METHODS: A total of 45 consecutive patients received 12 cycles of adjuvant FOLFOX for stage IIIb (n = 31) or IV (n = 14) CRC. Toxicity and disease-free survival (DFS) were analyzed retrospectively. RESULTS: The median dose intensities of oxaliplatin and 5-FU were 0.7 and 0.74, respectively. Oxaliplatin was discontinued in 10 (22%) patients due to an allergic reaction in five, neurotoxicity in four and gastrointestinal toxicity in one. No severe neurotoxicity occurred. The median duration from completion of treatment until complete recovery from peripheral neuropathy was 582 days (95% CI, 486-678). Two-year DFS for stages IIIb and IV was 56.9% and 56.3%, respectively (log-rank, P = 0.533). Univariate analysis revealed that severe vessel invasion, liver metastasis and higher baseline levels of CA19-9 were associated with shorter DFS in stage IV patients. Multivariate analysis including the selected biomarkers revealed none as a significant prognostic factor. CONCLUSION: Adjuvant FOLFOX was well tolerated in a Japanese cohort of both stage IIIb and IV CRC patients.