Complete surgical resection of cortisol secreting neuroendocrine thymic tumour: a case report

Neuroendocrine tumours of the thymus are extremely rare, with an estimated incidence of about 1 in 5 million people. Although data is limited, complete surgical resection remains the most significant prognostic factor for improved survival and disease-free outcomes, with adjuvant radiotherapy playing a role in cases where resection margins are close. This case report details the management of a cortisol secreting pT1bN0 atypical carcinoid of the thymus in a 43-year-old male.

43-year-old male presented with Cushing's syndrome and was diagnosed with a cortical secreting atypical carcinoid of the thymus. He underwent a robotic thymectomy. Recurrent disease on a DOTATATE-PET CT scan resulted in a second surgery involving complete resection of the mediastinal tumour which had invaded the pericardium, as well as wedge resection of the lung and lymph node sampling. This was followed by adjuvant radiotherapy due to close proximity of the lesion to the margin (< 3 mm).  DISCUSSION: Although paraneoplastic syndromes such as Cushing's syndrome are rare manifestations of thymic neuroendocrine tumours and can result in challenging diagnoses, it is vital to have a high index of suspicion towards ectopic ACTH secretion in order to facilitate timely initiation of multimodal disease management for these patients including surgery and radiotherapy.

Surgical management has been shown to offer the greatest prognosis in terms of overall survival and disease-free survival. Adjuvant radiotherapy plays a role where resection margins are close.