AbstractThe effect of general microwave hyperthermia and hepatic artery ligation (HAL) was tested on Wistar rats with a transplanted N‐methyl‐N‐nitroso‐guanidine‐induced adenocarcinoma in the liver. Total body hyperthermia (41.5°C for 1 hour, three times during 24 hours) was given on the same day as HAL, and 1, 2, and 3 days after. HAL induced a slower tumor growth than untreated controls. No additive effect was registered when total body microwave hyperthermia was added to HAL. When hyperthermia was added 2 days after HAL, there was a transient decrease in tumor volume as in the HAL series. Total body microwave hyperthermia added 3 days after HAL induced a faster tumor growth than after HAL alone. When hyperthermia was added the same day and 1 day after HAL, there was a 50%