Invasions veineuses dans l’adénocarcinome colique : intérêt d’une coloration des fibres élastiques

The aim of our study was to assess the value of Elastic stain in the diagnosis of venous invasion (VI) in colonic adenocarcinoma.All patients who undergone surgery for colonic adenocarcinoma at the University Hospital of Amiens, between 2004 and 2007, were included. Hematein-phloxin-saffron (HPS) stained slides of colectomy specimens were reviewed by two pathologists. Tumor blocks were stained with Elastic Stain (Roche - Ventana®). The presence or absence of VI, their number and localization were correlated with overall survival.Two hundred and thirty-one cases were investigated and 3274 slides were examined. VI were more often diagnosed by Elastic Stain than HPS stain (66% vs. 40%). Ninety percent of VI were revealed within the first 6 HPS slides, and from the first 5 in Elastic Stain. The presence of VI revealed by Elastic Stain and/or HPS was significantly associated with decreased overall survival in multivariate analysis (P=0.029), especially for stage IIA tumors (P=0.016). Tumor differentiation (P=0.006) and pTNM stage (P=0.001) were also independent prognostic factors. The localization and the number of VI were not prognostic factors.Our study confirms the prognostic value of VI, revealed by an elastic stain, in colonic adenocarcinoma. A systematic elastic stain of all tumor blocks (number at least 5) could be considered in the future, during pathological examination of colectomy for adenocarcinoma.