Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia presenting as a solitary lung nodule: a rare histopathological diagnosis

We present a case of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) in a 56-year-old woman, who presented to our emergency department with a 7-day history of exertional dyspnoea. Due to profound haemodynamic compromise, pulmonary embolism (PE) was suspected, and the patient underwent emergency thrombolysis on admission. A subsequent computerized tomography pulmonary angiogram revealed extensive bilateral PE. Incidentally, a 1.3 cm lesion within the right upper lobe, associated with pleural tethering, was identified. Positron emission tomography computerized tomography and, subsequently, histopathology revealed this lesion to be primary DIPNECH, a rare pre-invasive hyperplasia of neuroendocrine cells. While studies are scarce and cohort numbers are low, somatostatin analogues and protein kinase inhibitors have been proven to reduce symptoms and increase progression-free survival in DIPNECH, respectively.