Anatomic pathology and computed tomography of diffuse cystic lung diseases

. Cystic lung diseases are rare (orphan) diseases. Lung cysts are an important X-ray and morphological sign that contributes to the correct diagnosis. The aim of the researchwas to describe histologic features and computed tomography findings in patients with pulmonary Langerhans cell histiocytosis (PLCH), lymphangioleiomyomatosis (LAM), primary malignant lung tumors, and endometriosis of the lung. Materials and methods. We evaluated video-assisted surgical lung biopsies from 139 patients, with 86 patients having LAM, 47 having PLCH, and in threes having primary peripheral lung adenocarcinoma and endometriosis of the lung. The average age of patients with LAM was 41±10 years, LCG – 32±11 years, lung adenocarcinoma – 62±3.5 years, and endometriosis of the lung – 32±4.1 years. All patients had undergone high-resolution computed tomography of the lungs (HRCT) before the biopsy was obtained. We performed histological and immunohistochemical examinations of lung tissue specimens. Antibodies to CD1a, SMA, HMB-45, CD207 (langerin), CD10, receptors to progesterone, and estrogen were used in the study. Results. We described HRCT, histological, and immunohistochemical features of cystic lung diseases, including characteristics of the walls of cystic cavities in patients with PLCH, LAM, primary malignant lung tumors, and endometriosis of the lung. Conclusion. The variety of causes of lung cysts required a differential diagnosis, considering the patients’ ages, HRCT data indicating the localization of the pathological process, histology, and immunohistochemistry if necessary. Keywords: сystic lung diseases, computed tomography, pathological anatomy, Langerhans cell histiocytosis, lymphangioleiomyomatosis, malignant tumors, endometriosis