Surveillance colonoscopy improves survival in a cohort of subjects with a single mismatch repair gene mutation.
OBJECTIVE
Previous studies have shown a benefit for surveillance colonoscopy in heterogeneous groups of subjects with suspected or proven hereditary nonpolyposis colon cancer. The aim of this study was to investigate whether surveillance colonoscopy improves the survival in subjects who all carry a single mismatch repair gene defect.


METHODS
This is a prospective cohort study of 178 subjects who carry a mutation of the MLH1 gene in exon 13 (C1528T). They were offered surveillance colonoscopy between 1988 and 2006, and were followed up until September 2007.


RESULTS
One hundred and twenty-nine subjects underwent surveillance colonoscopy, and 49 declined. After a median follow up of 5 years, colorectal cancer was diagnosed in 14/129 (11%) subjects in the surveillance group and 13/49 (27%) in the nonsurveillance group (P = 0.019). Cancers in the surveillance group were at an earlier stage than in the nonsurveillance group (P = 0.032). Death from colorectal cancer occurred in three of 129 (2%) subjects in the surveillance group, and six of 49 (12%) in the nonsurveillance group (P = 0.021). The Kaplan-Meyer estimates for median survival from birth were 78 years in the surveillance group, and 55 years in the nonsurveillance group (P = 0.024). The Kaplan-Meyer estimates for median colorectal cancer-free survival from birth were 73 years in the surveillance group and 47 years in the nonsurveillance group (P = 0.0089).


CONCLUSIONS
Surveillance colonoscopy was associated with improved overall and colorectal cancer-related survival in subjects carrying a single mismatch repair gene mutation.
Stupart
D A
DA
Department of Surgery, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa. douglasstupart@yahoo.co.uk
Goldberg
P A
PA
Algar
U
U
Ramesar
R
R
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics*; D000328:Adult; D003113:Colonoscopy; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000175:diagnosis / Q000235:genetics / Q000401:mortality*; D018572:Disease-Free Survival; D005260:Female; D006579:Heterozygote; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D000070957:MutL Protein Homolog 1; D009687:Nuclear Proteins / Q000235:genetics*; D011159:Population Surveillance; D011446:Prospective Studies; D055815:Young Adult
D048868:Adaptor Proteins, Signal Transducing; C501486:MLH1 protein, human; D009687:Nuclear Proteins; D000070957:MutL Protein Homolog 1