Rare diffuse idiopathic pulmonary neuroendocrine cell hyperplasia: one case report and literature review

Rare diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) was first diagnosed in the early 1950s, but was not fully recognized and named until 1992. Literatures reported that DIPNECH usual was multiple and diffuse bilateral nodules, rare patients demonstrate the single nodule or ground glass nodule (GGN). We diagnosed one patient because of intermittent dry cough at least one year, Chest computed tomography (CT) found a purity GGN (pGGN) in the anterior segment, right upper lung lobe, and bronchoscopy didn't have any tumor in the bronchus in 2014. Continue follow-up 4 years, the nodule enlarged and became a mixed GGN (mGGN) in 2018 on chest CT. A diagnostics video-assisted thoracotomy with wedge resection in right upper lung lobe was performed. The pathology revealed that it was filled with neuroendocrine differentiation cells without penetration terminal bronchiole submucosal layer, immunohistochemical (IHC) staining were positive for CD-56, Cg-A, TTF, Syn and ki-67 (about 5%), leading to diagnosis of DIPNECH. A regular review of the chest CT showed no signs of tumor recurrence postoperative more than 1 year every 6 months, and we will continue follow-up. In conclusion, DIPNECH keeps stable evolution over several years, which is misdiagnosed and underdiagnosed usually. Patient who showed GGN on chest CT and had cough, dyspnea, wheezing, less frequently hemoptysis and so on, we should think of DIPNECH. Diagnosis depended on pathology and IHC staining, regular follow-up will lead to patient a long-term survival postoperative.