EC Cancer

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare pulmonary disorder typically affecting non-smoking women, and characterized by a proliferation of neuroendocrine cells combined with small airways disease. Diagnosis is frequently delayed due to nonspecific symptoms and imaging overlap with other conditions.

We present a case of a 73-year-old woman with progressive exertional dyspnea and incidental discovery of multiple bilateral pulmonary nodules. High-resolution CT (HRCT) demonstrated bilateral solid nodules, mosaic perfusion, and bronchial wall thickening. Pulmonary function tests showed moderate irreversible obstruction. PET-CT showed absent or faint uptake. Bronchoscopy and microbiological workup were non- contributory. The constellation of radiologic features, chronicity, and exclusion of alternative etiologies led to the diagnosis of DIPNECH.

DIPNECH remains underdiagnosed due to its nonspecific clinical presentation. Imaging plays a pivotal role, especially HRCT findings of small bilateral nodules and mosaic attenuation. Pulmonary function testing typically shows non-reversible obstructive patterns. Lung biopsy is diagnostic but may be avoided in characteristic cases.

This case emphasizes the importance of recognizing the imaging patterns of DIPNECH, particularly in women with chronic dyspnea and mosaic lung appearance. Long-term imaging comparison can support diagnosis in the absence of biopsy.

 Keywords: Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia (DIPNECH); High-Resolution CT (HRCT); PET-CT

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