Forty-four patients with advanced gastric adenocarcinoma were treated with the fluorouracil, adriamycin and mitomycin-C (FAM) regimen. One was excluded from response evaluation. Partial (PR) and minor (MR) response rates were 7 and 9% respectively. These patients enjoyed remission for a median of 7.0 months. Stabilization (S) occurred in 25% and lasted a median of 6.0 months. No response (NR) was associated with a median survival of 3 months (p less than 0.001). The predominant pretreatment factors to affect survival were diagnosis to treatment interval and initial CEA serum level. Performance status influenced survival less markedly. Toxicity was mainly myelosuppression, which resulted in death of one patient. 'Responders' had marrow suppression more frequently than NR. Comparison of PR + MR, PR + MR + S and NR patient groups showed median minimum WBC counts of 1.4 x 10(3), 2.6 x 10(3) and 4.3 x 10(3) per mm3 respectively. Leukopenia (less than 3,000/mm3) was associated with a median survival advantage of 9.5 versus 3.5 months (p less than 0.05) and did not depend significantly on given FAM dosage. The median dosage of FAM agents delivered to nonresponders was reduced. A trend of dose-response (including dose-survival) relationship was found but was inconclusive statistically.