Survival differences with immediate versus delayed chemotherapy for asymptomatic incurable metastatic colorectal cancer.

BACKGROUND: For patients with asymptomatic, incurable, metastatic colorectal cancer, palliative, systemic treatment can be started immediately, or can be delayed until disease-related symptoms occur. How the potential survival benefit of starting palliative, systemic treatment immediately after diagnosis weighs up against the potential side effects is currently under debate, and was investigated in this review. OBJECTIVES: To assess the effects of immediate versus delayed chemotherapy, with or without targeted therapy, on overall survival, toxicity, quality of life, progression-free survival, and compliance with chemotherapy for individuals with asymptomatic, metastatic, incurable colorectal cancer. SEARCH METHODS: We searched CENTRAL; 2018, Issue 8, MEDLINE Ovid, Embase Ovid, PsycINFO, the World Health Organization International Clinical Trials Registry Platform, and Clinicaltrials.gov, from inception to 23 August 2018. We did not apply limitations based on language or date of publication. We searched the reference lists of all included studies to identify trials that may not have been identified from the electronic searches. SELECTION CRITERIA: Randomised controlled trials evaluating immediate versus delayed chemotherapy in persons with asymptomatic, metastatic, incurable colorectal cancer. DATA COLLECTION AND ANALYSIS: We applied standard methodological procedures, according to the recommendations of Cochrane and Cochrane Colorectal Cancer. Two review authors independently reviewed the studies identified by literature searches, selected relevant trials, extracted data, and assessed risk of bias of the included studies. We used the Cochrane tool to assess risk of bias, Review Manager 5 software for meta-analysis, GRADE methods to evaluate the quality of the evidence, and GRADEpro GDT software to develop a 'Summary of findings' table. MAIN RESULTS: We included three randomised controlled trials (351 participants) investigating immediate versus delayed chemotherapy in people diagnosed with asymptomatic, metastatic, incurable colorectal cancer. Giving immediate versus delayed chemotherapy may make little or no difference to overall survival (hazard ratio (HR) 1.17, 95% confidence interval (CI) 0.93 to 1.46; 3 studies, 351 persons; low-quality evidence). For toxicity, giving immediate versus delayed chemotherapy may make little or no difference to the risk of grade 3 or 4 nausea and vomiting (risk ratio (RR) 0.84, 95% CI 0.31 to 2.25; 2 studies, 140 persons; very low-quality evidence), stomatitis (RR 1.10, 95% CI 0.47 to 2.55; 2 studies, 140 persons; very low-quality evidence), or diarrhoea (RR 0.69, 95% CI 0.34 to 1.40; 2 studies, 140 persons, very low-quality evidence). We are uncertain whether delayed chemotherapy made a difference to quality of life (very low-quality evidence), progression-free survival (low-quality evidence), or compliance with chemotherapy (low-quality evidence), as we had insufficient data to pool for these outcomes. AUTHORS' CONCLUSIONS: Based on a limited number of trials, very sparse data, and uncertainty of the evidence, this review was unable to establish whether there was a difference in overall survival or other clinically relevant outcomes, between immediate or delayed chemotherapy in persons with metastatic, incurable, colorectal cancer. The results should be interpreted with caution.

Differences between colon and rectal cancer in complications, short-term survival and recurrences.

PURPOSE: Many apparent differences exist in aetiology, genetics, anatomy and treatment response between colon cancer (CC) and rectal cancer (RC). This study examines the differences in patient characteristics, prevalence of complications and their effect on short-term survival, long-term survival and the rate of recurrence between RC and CC. METHODS: For all stage II-III CC and RC patients who underwent resection with curative intent (2006-2008) in five hospitals in the Netherlands, occurrence of complications, crude survival, relative survival and recurrence rates were compared. RESULTS: A total of 767 CC and 272 RC patients underwent resection. Significant differences were found for age, gender, emergency surgery, T-stage and grade. CC patients experienced fewer complications compared to RC (p = 0.019), but CC patients had worse short-term mortality rates (1.5 versus 6.7 % for 30-day mortality, p = 0.001 and 5.2 versus 9.5 % for 90-day mortality, p = 0.032). The adjusted HR (overall survival) for CC patients with complications was 1.57 (1.23-2.01; p < 0.001) as compared to patients without complications; for RC, the HR was 1.79 (1.12-2.87; p = 0.015). Relative survival analyses showed high excess mortality in the first months after surgery and a sustained, prolonged negative effect on both CC and RC. Complications were associated with a higher recurrence rate for both CC and RC; adjusted analyses showed a trend towards a significant association. CONCLUSION: Large differences exist in patient characteristics and clinical outcomes between CC and RC. CC patients have a significantly higher short-term mortality compared to RC patients due to a more severe effect of complications.

Adjuvant chemotherapy after preoperative (chemo)radiotherapy and surgery for patients with rectal cancer: a systematic review and meta-analysis of individual patient data.

BACKGROUND: The role of adjuvant chemotherapy for patients with rectal cancer after preoperative (chemo)radiotherapy and surgery is uncertain. We did a meta-analysis of individual patient data to compare adjuvant chemotherapy with observation for patients with rectal cancer. METHODS: We searched PubMed, Medline, Embase, Web of Science, the Cochrane Library, CENTRAL, and conference abstracts to identify European randomised, controlled, phase 3 trials comparing observation with adjuvant chemotherapy after preoperative (chemo)radiotherapy and surgery for patients with non-metastatic rectal cancer. The primary endpoint of interest was overall survival. FINDINGS: We analysed data from four eligible trials, including data from 1196 patients with (y)pTNM stage II or III disease, who had an R0 resection, had a low anterior resection or an abdominoperineal resection, and had a tumour located within 15 cm of the anal verge. We found no significant differences in overall survival between patients who received adjuvant chemotherapy and those who underwent observation (hazard ratio [HR] 0.97, 95% CI 0.81-1.17; p=0.775); there were no significant differences in overall survival in subgroup analyses. Overall, adjuvant chemotherapy did not significantly improve disease-free survival (HR 0.91, 95% CI 0.77-1.07; p=0.230) or distant recurrences (0.94, 0.78-1.14; p=0.523) compared with observation. However, in subgroup analyses, patients with a tumour 10-15 cm from the anal verge had improved disease-free survival (0.59, 0.40-0.85; p=0.005, p(interaction)=0.107) and fewer distant recurrences (0.61, 0.40-0.94; p=0.025, p(interaction)=0.126) when treated with adjuvant chemotherapy compared with patients undergoing observation. INTERPRETATION: Overall, adjuvant fluorouracil-based chemotherapy did not improve overall survival, disease-free survival, or distant recurrences. However, adjuvant chemotherapy might benefit patients with a tumour 10-15 cm from the anal verge in terms of disease-free survival and distant recurrence. Further studies of preoperative and postoperative treatment for this subgroup of patients are warranted. FUNDING: None.