Abstract
Diffuse pulmonary lymphangiomatosis (DPL) is a rare lymphatic disorder characterized by lymphatic channel proliferation. It is mostly reported in children and young adults. Here, we report a case involving a 52-year-old asymptomatic woman who presented with increased interstitial markings, as seen on a chest radiograph. Diffuse interstitial septal thickening was found on a serial follow-up chest computed tomography scan, and lymphangitic metastasis was the primary radiologic differential diagnosis. However, histologic sections of wedge resected lung revealed diffuse pleural and interlobular septal lymphatic proliferation characteristic of DPL.