Survival after colorectal cancer diagnosis is associated with colorectal cancer family history.
BACKGROUND
Colorectal cancer (CRC) family history is a known risk factor for CRC development; however, effects of CRC family history on survival after CRC diagnosis are less well-defined. Our population-based analysis investigates whether familial CRC cases exhibit improved survival compared with sporadic CRC cases.


METHODS
Cases enrolled in the University of California Irvine Gene-Environment Study of Familial Colorectal Cancer from 1994 to 1996 were analyzed, with follow-up through December 2006. Cases were categorized as familial or sporadic based on self-reported CRC family history in a first-degree relative. Univariate and multivariate survival analyses with Cox proportional hazards ratios were done for overall survival (OS) and CRC-SS (CRC-SS).


RESULTS
One thousand one hundred fifty-four CRC cases were analyzed, including 781 colon cancer and 373 rectal cancer cases. Nineteen percent of colon cases had family history of CRC in a first-degree relative, compared with 16% of rectal cancer cases. No statistically significant differences between familial and sporadic colon or rectal cancer cases were detected for age, gender, ethnicity, stage, tumor location, histology, tumor grade, or stage-specific treatment rendered. Among colon cancer cases, family history of CRC (versus no family history as a reference group) was associated with improved OS (adjusted hazard ratio, 0.760; 95% confidence interval, 0.580-0.997), but not with CRC-SS (hazard ratio, 0.880; 95% confidence interval, 0.621-1.246). No OS or CRC-SS differences were detected for rectal cancer cases.


CONCLUSIONS
CRC cases with family history of the disease have improved overall survival compared with sporadic CRC cases, a finding that is independent of other relevant clinical factors.
Zell
Jason A
JA
Chao Family Comprehensive Cancer Center, Division of Hematology/Oncology, Department of Medicine, University of California, Irvine, Irvine, CA 92697, USA. jzell@uci.edu
Honda
Jane
J
Ziogas
Argyrios
A
Anton-Culver
Hoda
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000401:mortality*; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012307:Risk Factors; D016019:Survival Analysis