Endocrine Abstracts

A 48-year-old non-smoking female was seen in the chest clinic for cough and breathlessness on a background of asthma type symptoms for 20 years. Her cough was exacerbated by inhalers, productive of yellow sputum and intermittent streaks of blood. On examination, her lungs were clear but coughed continuously with an unusual duration of five minutes. Pulmonary function test showed an obstructive picture. CT scan showed bronchiectasis with multiple small nodules scattered throughout the lungs ranging 4–8 mm. Subsequent scans over 2 years showed these nodules to have slightly increased in size. She remained extremely symptomatic with persistent cough despite steroid inhalers and mucolytics, although found slight benefit on mast cell stabilizer. She underwent video thoracoscopy which proceeded to left thoracotomy to obtain a lung biopsy. The pathological findings were consistent with diffuse idiopathic neuroendocrine neoplasia (DIPNECH). She was referred to Oncology for further management.

DIPNECH is a rare condition which is closely related to carcinoid tumours. Middle aged women represent 92% and most are non-smokers. Symptoms include chronic cough, dyspnea and wheezing. Imaging shows lung nodules and bronchiectasis. The histological appearance takes many forms comprising of generalised proliferation of scattered neuroendocrine cells, small nodules (neuroendocrine bodies) or a linear proliferation of pulmonary neuroendocrine cells superficial to the basement membrane. Extension beyond the basement membrane are termed tumourlets. Nodules >5 mm in diameter are classified as carcinoid tumours.

DIPNECH is typically an indolent and non-progressive disorder although it may progress to carcinoid tumour. Respiratory failure may occur. A ‘wait and watch’ approach can be an option but whenever possible, the patients should undergo surgical excision of the dominant lesion and somatostatin analogues may be considered for symptomatic or tumour control in patients with progressive disease.