G. Deredita et al., A SURVIVAL REGRESSION-ANALYSIS OF PROGNOSTIC FACTORS IN COLORECTAL-CANCER, Australian and New Zealand journal of surgery, 66(7), 1996, pp. 445-451
Background: Many prognostic factors of colorectal cancer are known but
their actual clinical validity is still uncertain. The aim of the pre
sent study was to verify, on the basis of our experience, the prognost
ic validy of variables for survival by using survival regression analy
sis. Methods: From January 1978 to December 1986 the prognostic factor
s for 192 patients were analysed. These patients had undergone surgica
l resection for colorectal cancer. The follow up was completed in ever
y patient by the end of December 1992, with a median follow up of 10 y
ears (range 6-14 years). The prognostic factors considered in the stat
istical analysis were age, sex, size of tumour, site, grade, direct sp
read, node involvement and stage (according to Astler-Coller and pTNM)
. Results: Of the prognostic factors, sex was the only one not to show
any prognostic significance. In the survival regression analysis we h
ave used an accelerated failure time model (equivalent to the Cox prop
ortional hazard model); age, grade and stage were significant covariab
les. Conclusions: Although clinical pathological staging (pTNM) appear
s as a pre-eminent prognostic factor, and as our analysis shows, it ne
eds a further variable (grading), which has been shown to affect the p
rognosis in a significant way.