Adjuvant chemotherapy for gastric cancer in Japan: present status and suggestions for rational clinical trials.

A review of the present status of adjuvant chemotherapy for gastric cancer in Japan has been made. The single use of mitomycin C (MMC) after curative gastrectomy, a multidrug combination of MMC, 5-fluorouracil (5FU) and cytosine arabinoside (CA) (MFC therapy), and a combination of inductive MFC followed by maintenance 5FU in an adjuvant setting have proved beneficial in subsets of moderately locally advanced diseases. The advantages of the Japanese trials seem to be attributable to perioperative chemotherapy with MMC and/or 5FU, obviously given in less amounts than in other countries, against minimum residual tumors following surgery. Effort should be directed, however, to improving the quality of data, at present biased by a number of exclusions and drop-outs which should not be considered negligible. The author mentions the beneficial use of a computer-assisted randomization system for avoiding the violation of entry criteria, and of controlling data quality with individual dose intensity (I.D.I.) and relative performance (R.P.) indices. Prerequisites for success in the adjuvant chemotherapy's clinical trial included planning effective regimens, proper selection of subjects and faithful performance of proposed regimens.