Low level microsatellite instability may be associated with reduced cancer specific survival in sporadic stage C colorectal carcinoma. Issue 1 (10th December 2004)

• Record Type: Journal Article
• Authors: Wright, C M; Dent, O F; Newland, R C; Barker, M; Chapuis, P H; Bokey, E L; Young, J P; Leggett, B A; Jass, J R; Macdonald, G A
• Is Part Of: Gut. Volume 54:Issue 1(2005)
• Page Start: 103
• Page End: 108
• Publication Date: 2004-12-10
• Subjects: CRC, colorectal cancer -- MMR, mismatch repair -- MSI, microsatellite instability -- MSI-H, MSI-high -- MSI-L, MSI-low -- MSS, microsatellite stable -- HNPCC, hereditary non-polyposis colorectal cancer -- PCR, polymerase chain reaction; microsatellite instability -- colorectal cancer -- prognosis; Gastroenterology -- Periodicals; 616.33
• DOI: 10.1136/gut.2003.034579
• Languages: English
• ISSNs: 0017-5749

Abstract

Abstract : Background: Colorectal cancers (CRCs) may be categorised according to the degree of microsatellite instability (MSI) exhibited, as MSI-high (MSI-H), MSI-low (MSI-L), or microsatellite stable (MSS). MSI-H status confers a survival advantage to patients with sporadic CRC. Aims: To determine if low levels of MSI are related to the clinicopathological features and prognosis of sporadic stage C CRC. Patients: A total of 255 patients who underwent resection for sporadic stage C CRC were studied. No patient received chemotherapy. Minimum follow up was five years. Methods: DNA extracted from archival malignant and non-malignant tissue was amplified by polymerase chain reaction using a panel of 11 microsatellites. MSI-H was defined as instability at ⩾40% of markers, MSS as no instability, and MSI-L as instability at >0% but <40% of markers. Patients with MSI-H CRC were excluded from analysis as they have previously been shown to have better survival. Results: Thirty three MSI-L and 176 MSS CRCs were identified. There was no difference in biological characteristics or overall survival of MSI-L compared with MSS CRC but MSI-L was associated with poorer cancer specific survival (hazard ratio 2.0 (95% confidence interval 1.1–3.6)). Conclusions: Sporadic MSI-L and MSS CRCs have comparable clinicopathological features. Further studies are required to assess the impact of MSI-L on prognosis.