Colorectal cancer (CRC) is the most common tumour type in both sexes combined in Western countries. Although screening programmes including the implementation of faecal occult blood test and colonoscopy might be able to reduce mortality by removing precursor lesions and by making diagnosis at an earlier stage, the burden of disease and mortality is still high. Improvement of diagnostic and treatment options increased staging accuracy, functional outcome for early stages as well as survival. Although high quality surgery is still the mainstay of curative treatment, the management of CRC must be a multi-modal approach performed by an experienced multi-disciplinary expert team. Optimal choice of the individual treatment modality according to disease localization and extent, tumour biology and patient factors is able to maintain quality of life, enables long-term survival and even cure in selected patients by a combination of chemotherapy and surgery. Treatment decisions must be based on the available evidence, which has been the basis for this consensus conference-based guideline delivering a clear proposal for diagnostic and treatment measures in each stage of rectal and colon cancer and the individual clinical situations. This ESMO guideline is recommended to be used as the basis for treatment and management decisions.

Purpose: To report the final efficacy findings and biomarker analysis from the NO16968 trial comparing bolus fluorouracil/folinic acid (FU/FA) with capecitabine plus oxaliplatin (XELOX) in resected stage III colon cancer. Patients and Methods: After curative resection, patients were randomly assigned to receive XELOX, as oxaliplatin 130 mg/m² on day 1 and capecitabine 1,000 mg/m² twice daily on days 1 to 14 every 3 weeks, or bolus FU/FA, as the Mayo Clinic or Roswell Park regimens, for 6 months. The primary end point was disease-free survival (DFS). Secondary end points included overall survival (OS). Results: The intention-to-treat population comprised 1,886 patients (XELOX, n = 944; FU/FA, n = 942). Seven-year DFS rates were 63% and 56% in the XELOX and FU/FA groups, respectively (hazard ratio [HR], 0.80; 95% CI, 0.69 to 0.93; P = .004). Seven-year OS rates were 73% and 67% in the XELOX and FU/FA groups, respectively (HR, 0.83; 95% CI, 0.70 to 0.99; P = .04). A total of 68% and 77% of patients who experienced relapse or a new colorectal cancer in the XELOX and FU/FA groups, respectively, received drug treatment for metastatic disease. Four hundred ninety-eight patients consented to the biomarker analysis: 242 in the XELOX group and 256 in the FU/FA group. Low tumor expression of dihydropyrimidine dehydrogenase may be predictive for XELOX efficacy; in the XELOX group, for high versus low dihydropyrimidine dehydrogenase expression levels, DFS HR was 2.45 (95% CI, 1.55 to 3.86; P < .001), and OS HR was 2.75 (95% CI, 1.65 to 4.59; P < .001). In the FU/FA group, no statistically significant associations were observed between any tumor biomarker and outcomes. Conclusion: XELOX improved OS compared with bolus FU/FA in patients with resected stage III colon cancer after a median follow-up of almost 7 years. XELOX should be considered a standard adjuvant treatment option in patients with stage III disease. Tumoral dihydropyrimidine dehydrogenase expression is a promising predictive, and potentially, highly clinically relevant, biomarker for XELOX efficacy requiring further prospective evaluation.

Purpose: To compare the efficacy of cediranib (a vascular endothelial growth factor receptor tyrosine kinase inhibitor [VEGFR TKI]) with that of bevacizumab (anti–VEGF-A monoclonal antibody) in combination with chemotherapy as first-line treatment for advanced metastatic colorectal cancer (mCRC). Patients and Methods: HORIZON III [Cediranib Plus FOLFOX6 Versus Bevacizumab Plus FOLFOX6 in Patients With Untreated Metastatic Colorectal Cancer] had an adaptive phase II/III design. Patients randomly assigned 1:1:1 received mFOLFOX6 [oxaliplatin 85 mg/m² and leucovorin 400 mg/m² intravenously followed by fluorouracil 400 mg/m² intravenously on day 1 and then continuous infusion of 2,400 mg/m² over the next 46 hours every 2 weeks] with cediranib (20 or 30 mg per day) or bevacizumab (5 mg/kg every 14 days). An independent end-of-phase II analysis concluded that mFOLFOX6/cediranib 20 mg met predefined criteria for continuation; subsequent patients received mFOLFOX6/cediranib 20 mg or mFOLFOX6/bevacizumab (randomly assigned 1:1). The primary objective was to compare progression-free survival (PFS). Results: In all, 1,422 patients received mFOLFOX6/cediranib 20 mg (n = 709) or mFOLFOX6/bevacizumab (n = 713). Primary analysis revealed no significant difference between arms for PFS (hazard ratio [HR], 1.10; 95% CI, 0.97 to 1.25; P = .119), overall survival (OS; HR, 0.95; 95% CI, 0.82 to 1.10; P = .541), or overall response rate (46.3% v 47.3%). Median PFS and OS were 9.9 and 22.8 months for mFOLFOX6/cediranib and 10.3 and 21.3 months for mFOLFOX6/bevacizumab. The PFS upper 95% CI was outside the predefined noninferiority limit (HR < 1.2). Common adverse events with more than 5% incidence in the cediranib arm included diarrhea, neutropenia, and hypertension. Cediranib-treated patients completed fewer chemotherapy cycles than bevacizumab-treated patients (median 10 v 12 cycles). Patient-reported outcomes (PROs) were significantly less favorable in cediranib-treated versus bevacizumab-treated patients (P < .001). Conclusion: Cediranib activity, in terms of PFS and OS, was comparable to that of bevacizumab when added to mFOLFOX6; however, the predefined boundary for PFS noninferiority was not met. The cediranib safety profile was consistent with previous studies but led to less favorable PROs compared with bevacizumab. Investigation of oral TKIs in CRC continues.

PURPOSE: The PETACC 6 trial investigates whether the addition of oxaliplatin to preoperative capecitabine-based chemoradiation and postoperative capecitabine improves disease-free survival (DFS) in locally advanced rectal cancer. METHODS: Between November 2008 and September 2011, patients with rectal adenocarcinoma within 12 cm from the anal verge, T3/4 and/or node positive, were randomly assigned to 5 weeks preoperative capecitabine-based chemoradiation (45-50.4 Gy) followed by six cycles of adjuvant capecitabine, both without (control arm, 1) or with (experimental arm, 2) oxaliplatin. The primary end point was improvement of 3-year DFS by oxaliplatin from 65% to 72% (hazard ratio [HR], 0.763). RESULTS: A total of 1,094 patients were randomly assigned (intention to treat), and 1,068 eligible patients started their allocated treatment (arm 1, 543; arm 2, 525), with completion of protocol treatment in 68% (arm 1) v 54% (arm 2). A higher rate of grade 3/4 adverse events was reported in the experimental arm (14.4% v 37.3% and 23.4% v 46.6% for neoadjuvant and adjuvant treatment, respectively). At a median follow-up of 68 months (interquartile range, 58-74 months), 157 and 156 DFS events were observed in arms 1 and 2, respectively (adjusted HR, 1.02; 95% CI, 0.82 to 1.28; P = .835). Three-year DFS rate was not different, with 76.5% (95% CI, 72.7% to 79.9%) in arm 1, which is higher than anticipated, and 75.8% (95% CI, 71.9% to 79.3%) in arm 2. The 7-year DFS and overall survival (OS) rates were not different as well, with DFS of 66.1% v 65.5% (HR, 1.02) and OS of 73.5% v 73.7% (HR, 1.19) in arms 1 and 2, respectively. Subgroup analyses revealed heterogeneity in treatment effect according to German versus non-German site location, without detectable confounding factors in multivariable analysis. CONCLUSION: The addition of oxaliplatin to preoperative capecitabine-based chemoradiation and postoperative adjuvant chemotherapy impairs tolerability and feasibility and does not improve efficacy.