The prevalence and prognostic significance of argyrophil cells in colorectal carcinomas.

The presence of argyrophil cells in the proliferative compartment of noncarcinoid carcinomas of the GI tract is well-documented; however, their prevalence and prognostic significance in colorectal carcinomas have never been systematically investigated and reported in the English literature. We applied the Churukian-Schenk argyrophil stain, a histochemical technique previously shown to be the most effective for demonstrating argyrophil cells, to 94 carcinomas of the colon and rectum from patients in whom a minimum 5-year follow-up was available. The 94 cases included 25 nonmucinous colonic and 25 nonmucinous rectal adenocarcinomas; 25 mucinous adenocarcinomas from all sites; and 19 undifferentiated carcinomas from all sites. Twenty control colorectal carcinoids all gave a positive argyrophil stain. Nineteen (20%) of the 94 carcinomas contained argyrophil cells as follows: adenocarcinoma of the colon, 52%; adenocarcinoma of the rectum, 16%; mucinous adenocarcinoma, 4%; and undifferentiated carcinoma, 5%. Crude 5-year survival rates were: carcinoids 80%; all carcinomas containing argyrophil cells, 37%; all without argyrophil cells, 27%. Chi-square between the later two groups was 0.723 (p less than 0.5). Because of the intrinsically poorer prognosis of mucinous and undifferentiated carcinomas, a comparison of survival rates was made excluding these tumors; chi-square was 0.095 (p less than 0.8). We conclude that argyrophil cells are commonly present in nonmucinous adenocarcinoma of the colon, but are less common in nonmucinous adenocarcinomas of the rectum and rare in mucinous and undifferentiated carcinomas. The presence of argyrophil cells did not influence prognosis in this series of cases.