K Polom1,2, L Marano3, D Marrelli1, R De Luca4, G Roviello5,6, V Savelli1, P Tan7, F Roviello1. 1. Department General Surgery and Surgical Oncology, University of Siena, Siena, Italy. 2. Department of Surgical Oncology, Medical University of Gdansk, Gdansk, Poland. 3. General, Minimally Invasive and Robotic Surgery, Department of Surgery, San Matteo degli Infermi Hospital, Spoleto, Italy. 4. Department of Surgical Oncology, National Cancer Research Centre-Istituto Tumori G. Paolo II, Bari, Italy. 5. Department of Oncology, Medical Oncology Unit, San Donato Hospital, Arezzo, Italy. 6. Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy. 7. Cancer and Stem Cell Biology, Duke-National University of Singapore Graduate Medical School, Genome Institute of Singapore, Cancer Science Institute of Singapore, National University of Singapore, and Cellular and Molecular Research, National Cancer Centre, Singapore.
Abstract
BACKGROUND: Several associations between microsatellite instability (MSI) and other clinicopathological factors have been reported in gastric cancer, but the results have been ambiguous. This systematic review and meta-analysis investigated the relationship between MSI and overall survival and clinicopathological characteristics of patients with gastric cancer. METHODS: A systematic literature search of the PubMed, Cochrane and Ovid databases until 31 January 2016 was performed in accordance with the PRISMA statement. The articles were screened independently according to PICO (population, intervention, comparator, outcome) eligibility criteria. All eligible articles were evaluated independently by two reviewers for risk of bias according to the Quality In Prognosis Study tool. RESULTS: Overall, 48 studies with a total of 18 612 patients were included. MSI was found in 9·2 per cent of patients (1718 of 18 612), and was associated with female sex (odds ratio (OR) 1·57, 95 per cent c.i. 1·31 to 1·89; P < 0·001), older age (OR 1·58, 2·20 to 1·13; P < 0·001), intestinal Laurén histological type (OR 2·23, 1·94 to 2·57; P < 0·001), mid/lower gastric location (OR 0·38, 0·32 to 0·44; P < 0·001), lack of lymph node metastases (OR 0·70, 0·57 to 0·86, P < 0·001) and TNM stage I-II (OR 1·77, 1·47 to 2·13; P < 0·001). The pooled hazard ratio for overall survival of patients with MSI versus those with non-MSI gastric cancer from 21 studies was 0·69 (95 per cent c.i. 0·56 to 0·86; P < 0·001). CONCLUSION: MSI in gastric cancer was associated with good overall survival, reflected in several favourable clinicopathological tumour characteristics.
BACKGROUND: Several associations between microsatellite instability (MSI) and other clinicopathological factors have been reported in gastric cancer, but the results have been ambiguous. This systematic review and meta-analysis investigated the relationship between MSI and overall survival and clinicopathological characteristics of patients with gastric cancer. METHODS: A systematic literature search of the PubMed, Cochrane and Ovid databases until 31 January 2016 was performed in accordance with the PRISMA statement. The articles were screened independently according to PICO (population, intervention, comparator, outcome) eligibility criteria. All eligible articles were evaluated independently by two reviewers for risk of bias according to the Quality In Prognosis Study tool. RESULTS: Overall, 48 studies with a total of 18 612 patients were included. MSI was found in 9·2 per cent of patients (1718 of 18 612), and was associated with female sex (odds ratio (OR) 1·57, 95 per cent c.i. 1·31 to 1·89; P < 0·001), older age (OR 1·58, 2·20 to 1·13; P < 0·001), intestinal Laurén histological type (OR 2·23, 1·94 to 2·57; P < 0·001), mid/lower gastric location (OR 0·38, 0·32 to 0·44; P < 0·001), lack of lymph node metastases (OR 0·70, 0·57 to 0·86, P < 0·001) and TNM stage I-II (OR 1·77, 1·47 to 2·13; P < 0·001). The pooled hazard ratio for overall survival of patients with MSI versus those with non-MSI gastric cancer from 21 studies was 0·69 (95 per cent c.i. 0·56 to 0·86; P < 0·001). CONCLUSION: MSI in gastric cancer was associated with good overall survival, reflected in several favourable clinicopathological tumour characteristics.