No abstract

Aim The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30) assesses the health-related quality of life of patients in cancer trials. There are currently no minimally important difference (MID) guidelines for the EORTC QLQ-C30 for colorectal cancer (CRC). This study aims to estimate MIDs for the EORTC QLQ-C30 scales in patients with advanced CRC treated with chemotherapy and enrolled in clinical trials. Method The data were obtained from three published EORTC trials that treated CRC patients using chemotherapy. Potential anchors were selected from clinical variables based on their correlation with EORTC QLQ-C30 scales. Anchor-based MIDs for within-group change and between-group change were estimated via the mean change method and linear regression, respectively, and summarized using weighted correlation. Distributionbased MIDs were also examined. Results Anchor-based MIDs were determined for deterioration in 8 of the 14 EORTC QLQ-C30 scales and in 9 scales for improvement, and varied by scale, direction of change and anchor. MIDs for improvement (deterioration) ranged from 6 to 18 (À11 to À5) points for within-group change and 5 to 15 (À10 to À4) for between-group change. Summarized MIDs (in absolute values) per scale mostly ranged from 5 to 10 points. Conclusions These findings have clinical relevance for the interpretation of treatment efficacy and the design of clinical trials by informing sample size requirements.

Background:Clinical trials comparing laparoscopic gastrectomy (LG) versus traditional open gastrectomy (OG) have been planned, their surgical outcomes reported but their oncologic outcomes are still pending. Consequently, we have conducted this large-scale historical cohort study to provide relevant information rapidly to guide our current practice.Methods:Through a consensus meeting involving surgeons, biostatisticians, and epidemiologists, 30 variables of preoperative information possibly influencing surgeons’ choice between LG versus OG and potentially associating with outcomes were identified to enable rigorous estimation of propensity scores. A total of 4235 consecutive patients who underwent gastrectomy for gastric adenocarcinoma were identified and their relevant data were gathered from the participating hospitals. After propensity score matching, 1848 patients (924 each for LG and OG) were selected for comparison of long-term outcomes.Results:In the propensity-matched population, the 5-year overall survival was 96.3% [95% confidence interval (CI) 95.0–97.6] in the OG as compared with 97.1% (95% CI, 95.9–98.3) in LG. The number of all-cause death was 33/924 in the OG and 24/924 in the LG through the entire period, and the hazard ratio (LG/OG) for overall death was 0.75 (95% CI, 0.44–1.27; P = 0.290). The 3-year recurrence-free survival was 97.4% (95% CI, 96.4–98.5) in the OG and 97.7% (95% CI, 96.5–98.8) in the LG. The number of recurrence was 22/924 in the OG and 21/924 in the LG through the entire period, and the hazard ratio was 1.01 (95% CI, 0.55–1.84; P = 0.981).Conclusions:This observational study adjusted for all-known confounding factors seems to provide strong enough evidence to suggest that LG is oncologically comparable to OG for gastric cancer.