Prominent cytoplasmic staining for IFN-γ mRNA were detected in 13 out of 35 of the adrenal cortical adenomas, two out of four of the cortical carcinomas, nine out of 30 of the phaeochromocytomas, 16 out of 60 of the clear cell RCC, two out of nine of the tumour adjacent tissues in adrenal cortexes and two out of five of the medullas. This evidence concerns the gene IFNG and adrenal cortex adenoma.