The response of s.c. primary and metastatic Lewis lung carcinoma to five antitumour platinum complexes with or without tolerable whole-body hyperthermia (60 min to reach temperature then 60 min at 42 degrees C) was examined. The whole-body hyperthermia treatment produced about 2.8 days of tumour growth delay in the s.c. tumours. The addition of whole-body hyperthermia to treatment with each of the platinum complexes was well tolerated by the animals and increases of 1.6-2.0-fold in tumour growth delay resulted with the combined treatment compared with the platinum complexes alone. The combination of etanidazole (1 g/kg) and the platinum complexes followed by whole-body hyperthermia produced marked increases in tumour growth delay ranging from 2.5- to 3.6-fold over the growth delays obtained with the platinum complexes alone. FSaLLC tumour cell survival and bone marrow CFU-GM experiments indicated that local hyperthermia (43 degrees C, 30 min) produced greater potentiation of the cytotoxicity of three platinum complexes than did whole-body hyperthermia (42 degrees C, 60 min). Only the complete treatments including whole-body hyperthermia/etanidazole and the platinum complexes were effective in significantly reducing the numbers of lung metastases formed from s.c. primary tumours. Serum urea nitrogen and creatinine levels were monitored over a time-course post-treatment. Although some treatment combinations caused elevations in these normal tissue parameters by day 12 post-treatment both serum urea nitrogen and serum creatinine returned to the levels of the untreated control animals.