Prognostic significance of in vitro thymidine uptake in patients with colorectal carcinoma.

Abstract

In 127 patients with colorectal carcinoma, we measured thymidine uptake by tumor cells cultured in a semisolid medium and compared the influence of various parameters on survival by univariate and multivariate analysis. Fifty-four of the 127 carcinomas (42.5%) incorporated > 1,000 cpm of tritiated thymidine per culture dish and were designated as the high-uptake group, while the other tumors (57.5%, 73/127) were designated as the low-uptake group. There was no significant correlation between high or low thymidine uptake and most of the clinicopathological characteristics of the patients. Patients in the high-uptake had a poor prognosis and a 7-year survival rate of 32.6%, which was significantly different from the rate of 69.3% in the low-uptake group (P < 0.0005). Multivariate analysis showed that thymidine uptake was one of the variables strongly associated with survival in our study population. Thus, it is concluded that thymidine uptake by tumor cells has a high capacity of predicting prognosis, independent of its relationship to other variables. Furthermore, it seems to us that thymidine uptake can help in selecting those patients with colorectal carcinoma who are most likely to benefit from perioperative adjuvant therapy.