Adrenal cortical carcinoma is a rare and highly malignant tumor. This retrospective study includes 99 patients (57 males and 42 females) reported to The Cancer Registry of Norway during the 15 year period from 1970 to 1984. The age adjusted incidence was 1.5 per million per year. Eighty-one patients were diagnosed with adrenal cortical carcinoma when still alive. In 18 cases the diagnosis was first made at autopsy. Median age at diagnosis was 54 years (range 2-88 years) with a slight male predominance. Information about initial symptoms was available in 67 patients, of whom 26 patients (18 females and 8 males) presented with clinically functioning tumors, the Cushing syndrome and virilization being most frequently encountered. Only 28 (35%) of 81 patients diagnosed when still alive had tumors confined to the adrenals. Half of the patients had distant metastases, with lungs and liver being the most frequent sites. Sixty-one patients underwent surgery; 51 patients had a radical or debulking operation and 10 patients had laparotomy with tumor biopsy. After a complete follow-up for at least 6 years (range 6-21 years), only 9 patients were still alive. Early stage (Stage I and II) and curative resection had a significant impact on the outcome of this disease. To improve prognosis, early diagnosis and radical surgery, if feasible, are needed.