Recurrent atypical adrenocorticotrophic hormone (ACTH) secreting carcinoid causing Cushing`s syndrome
G Mlawa, K Lambert, A Norris, JSW Li Voon Chong
Royal Hampshire County Hospital,Romsey Road,SO22 5DG, Winchester,UK
Atypical carcinoid tumours are rare which account for about 15% of all carcinoid tumours. Some of those tumours secrete adrenocorticotrophic hormone (ACTH) causing Cushing`s syndrome.We present a case which recurred 16 years after being first diagnosed.
A 39 years old woman was referred with few months history of weight gain, irregular menstrual periods, muscle aches, difficult going up the stairs, headaches and blurred vision.She was initially diagnosed with ectopic thoracic carcinoid leading to Cushing`s syndrome in 1995 while living in London and this was surgically treated. She was symptom free until early 2011.Her 9 am cortisol was raised at 770nmol/L, 24 hour urinary cortisol was 1992nmol/24hr, and non-suppression with both low and high dose dexamethasone suppression test. Her ACTH was high at 118ng/L. CT chest showed 2.5x3x1.9cm mass on left side of superior mediastinum adjacent to arch of the aorta.
She was started on metyrapone 250mg three times/day. Resection of the tumour was carried out in May 2011. At surgery the tumour was found to be involving the pulmonary vessels, phrenic nerve, and left upper lobe. Histology confirmed atypical carcinoid tumour with approximately one mitotic figure per 5 high power fields. She remains asymptomatic and her latest 24 urinary cortisol was 102nmol/24hr.
Atypical adrenocorticotrophic hormone (ACTH ) secreting tumours are uncommon, and together with typical carcinoid tumours constitutes less than 5% of all lung tumours.
This case demonstrates that the tumour can be very slow growing in nature. Patients with atypical adrenocorticotrophic hormone ( ACTH) secreting carcinoid tumours need to be followed up and screened for Cushing`s for many years.