Endocrine Abstracts

Introduction: Ectopic adrenocorticotropic hormone (ACTH) production by the pulmonary neuroendocrine tumour (p-NET) is rare, and is considered an aggressive variant of carcinoid tumours with poor prognosis.

Case presentation: 59-year-old male with fast progressing generalized fatigue, abdominal discomfort, and diarrhea was hospitalized in gastroenterology unit of Hospital of Lithuanian University of Health Sciences, Kauno klinikos (HLUHS KK). Digestive tract diseases were ruled out. Persistent hypokalaemia (up to 2.2 mmol/l) was observed and endocrine pathology changes were considered. Examinations revealed markedly elevated plasma ACTH (44.4 pmol/l) and cortisol (>1665 nmol/l) levels, diabetes, osteoporosis. No suppression of serum cortisol level with high-dose dexamethasone test was found, confirming ACTH dependent Cushing syndrome. The treatment with Metirapone was started. Pituitary and abdominal magnetic resonance imaging (MRI), abdominal computer tomography (CT) scans were normal. Thoracic CT scan showed nodules in the S2, S3, S6 of the left lung. No cytologic changes were found in repetitive bronchial leachates through endoscopic bronchoscopy. There were two episodes of pneumonia (Pseudomonas aeruginosa) and two episodes of sepsis (Staphylococcus aureus and Enterococcus faecium). Suspected fungal infection, intended antifungal treatment. Single nodule in S3 of the left lung with no changes in size was found in repeated chest CT. ^99MTc-tectrotyd SPECT-CT showed left lung S3 neuroendocrine tumour. The radical surgery (bilobectomia superior sinistri) was performed. Histological result was well-differentiated p-NET (pT1a N0 R0 G1). No radiochemotherapy was suggested. On the follow up visit after three months normal glycaemia, potassium and cortisol were found.

Conclusion: We present ectopic ACTH secreting neuroendocrine lung carcinoma with likely good prognosis. No clearly defined guidelines of follow up exist.