BES2002 Poster Presentations Clinical Case Reports (60 abstracts)
1Department of Endocrinology, Aberdeen Royal Infirmary, Aberdeen, UK; 2Department of Oncology, Aberdeen Royal Infirmary, Aberdeen, UK.
Thymic carcinoma is a rare but aggressive cause of ectopic ACTH secretion, with fewer than 100 reported cases.
Hypokalaemic alkalosis was found in a 38 year old woman who presented with a 2-week history of leg swelling, fatigue and dyspnoea. She was not obviously Cushingoid.
ACTH-dependent Cushing's Syndrome was confirmed biochemically: urinary free cortisol (UFC) >8500nmol/day and serum cortisol 4060nmol/l, (no suppression on 8mg dexamethasone). Adrenal CT showed massive bilateral adrenal hyperplasia.
At this stage she developed paranoid psychosis: she refused to eat or drink and emergency ECT was initially considered. However after commencing metyrapone and aminoglutethemide, serum cortisol fell to 700 nmol/l and her psychiatric manifestations improved.
Whole body CT scan revealed a 4cm thymic mass, with corresponding uptake of 111In-pentetreotide. Surgical pathology confirmed an aggressive carcinoid tumour with lymphatic and venous invasion and positive immunostaining for ACTH. Serum cortisol remained around 400nmol/l, suggesting the presence of residual tumour. She subsequently received radiotherapy to the mediastinum and chemotherapy with cisplatin and etoposide.
At 6 months after surgery, she is asymptomatic with normal ACTH, ACTH precursors and UFC < 90nmol/day. Her management required multidisciplinary intervention from endocrine, psychiatric, surgical and oncology teams providing several different treatment modalities. Despite her good responses, the long-term prognosis remains guarded with reported 10-year survival of 30-60%.