Adrenocortical Carcinoma

Adrenocortical carcinoma is a cancer that arises from the outer layer of the adrenal gland — a small structure that sits near the kidney and produces hormones involved in metabolism, stress response, and fluid balance. In dogs, this type of tumour can behave in two broad ways: it may produce excessive amounts of hormones (most often cortisol, leading to signs similar to Cushing's syndrome), or it may grow without obvious hormonal activity, in which case signs relate to the mass itself or to spread elsewhere in the body. Owners often arrive at this page after imaging has identified a mass on or near the adrenal gland, or because their dog has been investigated for persistent weight gain, increased thirst, muscle weakness, or a swollen abdomen. Some dogs show no outward signs at all, and the finding is incidental during imaging for another reason. The behaviour of these tumours varies: some remain slow-growing and localised for months or years, while others invade nearby structures or spread to the liver, lungs, or lymph nodes relatively early. This page explores the signals that may suggest adrenocortical carcinoma, what is happening at a tissue and hormonal level, how the condition is investigated through imaging and laboratory tests, and the range of approaches that exist — from surgical removal to medical management of hormone excess or monitoring in cases where intervention carries significant risk.