Adrenocortical carcinoma evolving after diagnosis of preclinical Cushing's syndrome in an adrenal incidentaloma. A case report.

A 43-year-old female patient underwent abdominal ultrasonography and CT scan because of uncharacteristic abdominal pain. A 3-cm homogeneous adrenal tumor was diagnosed. The endocrine tests revealed an adrenal preclinical Cushing's syndrome (PCS). Due to the latent hormone excess we decided to operate on the adrenal tumor. Since the tumor was small, laparoscopic adrenalectomy was performed. Histological evaluation showed an adrenocortical tumor of undetermined nature. Four months later the patient presented with a metastasizing cortisol- and androgen-producing adrenocortical carcinoma (ACC). After pretreatment with ketoconazole to suppress the biosynthesis of adrenal steroids under substitution with hydrocortisone, we reduced the tumor load by surgery. Postoperatively we continued ketoconazole and started o, p'-dichlorodiphenyldichloroethane as well as chemotherapy with doxorubicin and suramin. However, the patient died from ACC 7 months after adrenalectomy. It is known from several reports that PCS may persist clinically silently or may progress to full-blown Cushing's syndrome. This is the first time a malignant course of PCS is described. Independent of the initial therapeutic strategy of PCS, i. e. surgery or regular follow-up visits, we must be aware that also relatively small adrenal tumors can harbor malignancy.