Evaluation of sensitivity to 5-FU on the basis of TS and DPD activity in micro tissue specimens

651 Background: Preoperative assessment of the anticancer drug sensitivity of tumors plays an important role in the selection of therapy. Evaluation of the 5-FU sensitivity of micro tissue specimens obtained by techniques such as core needle biopsy is often performed before preoperative chemotherapy. The addition of 5-Fluorouracil(F) or its derivatives to AC (EC), the current mainstay of therapy, may further enhance response rate. TS and DPD are used to evaluate the sensitivity and predict the response of tumors to fluoropyrimidine derivatives. Conventional techniques for measuring the activities of these enzymes require large tissue samples, often difficult to obtain before surgery. In contrast, assay of mRNA by PCR permits the use of micro tissue samples obtainable by biopsy. Methods: We measured TS and DPD enzyme activities and mRNA levels in 48 cases of tumor tissue and in the surrounding normal tissue. We also gave 5-FU postoperatively to 107 women with early-stage breast cancer, and divided tissue s...