Unmasking Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia: Clinicopathologic Features of a Rare Pulmonary Disorder

Document Type

Conference Proceeding

Publication Date

5-1-2025

Publication Title

Am J Respir Crit Care Med

Abstract

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare and poorly understood lung disorder that predominantly affects women. It often presents with nonspecific pulmonary symptoms, leading to delayed diagnosis. Given the limited literature, we aimed to investigate its clinical, radiologic, and pathologic characteristics.We conducted a retrospective study analyzing 33 patients histologically diagnosed with DIPNECH. Clinical and radiologic data were collected from electronic medical records. Hematoxylin and eosin (H&E) slides and relevant immunohistochemistry slides were reviewed. Clinical follow-up data were obtained.Patients were categorized as symptomatic (n = 13) or asymptomatic (n = 20). In the symptomatic group, the median age was 70 years, with 92.3% being female. Ethnic distribution was 69.2% Caucasian, 23.1% African American, and 7.7% Italian. In the asymptomatic group, the median age was 75 years, with 85% being female. Ethnic distribution was 75% Caucasian and 25% African American.Among symptomatic patients, 76.9% experienced shortness of breath, followed by cough, wheezing, and hemoptysis. Radiologically, all patients had lung nodules, with the largest measuring 3.2 cm. In the symptomatic group, 39% were non-smokers, while 61% had a smoking history. Among asymptomatic patients, 70% were smokers and 30% were non-smokers.All patients underwent surgical resection of radiologically identified nodules, with favorable post-surgical outcomes.Histologic examination revealed neuroendocrine hyperplasia, multiple carcinoid tumorlets, and carcinoid tumors in all cases. Constrictive bronchiolitis was observed in six cases. Notably, two patients had a concurrent diagnosis of adenocarcinoma, one of whom was also found to have brain metastasis secondary to adenocarcinoma at the time of diagnosis. Additionally, two patients had complex oncologic histories: one with prior squamous cell carcinoma followed by adenocarcinoma (both treated), and the other initially diagnosed with adenocarcinoma, later progressing to small cell carcinoma (treated accordingly). Both patients ultimately developed DIPNECH in subsequent years. Of the cohort, 31 patients are alive, while two were lost to follow-up. None required additional treatment for DIPNECH beyond surgical resection. This study represents the largest single- institution series of DIPNECH patients reported to date. The condition primarily affects older women and generally has a favorable prognosis. However, unlike previous reports, shortness of breath was the most prevalent symptom. Notably, none required octreotide treatment. Our findings emphasize the importance of vigilant imaging and follow-up, particularly in smokers, to prevent disease progression and improve long-term outcomes.

Volume

211

First Page

2

Find It @ Sladen

Share

COinS