Bronchiole adenoma/pulmonary ciliated mucinous nodular papillary tumor: Case series and literature review

Objective: To analyze the clinical-pathological characteristics of 3 cases of bronchiolar adenoma/pulmonary ciliary mucinous nodular papillary tumors, and to improve the understanding of bronchiolar adenoma (BA)/ciliated muconodular papillary tumors (CMPT) (bronchiolar adenoma/ciliated muconodular papillary tumor). Methods: Retrospective analysis was done on the clinical information, diagnosis, and treatment of 3 instances of BA/CMPT at the Second People’s Hospital of Weifang City. By scanning the CNKI, Wanfang, VIP database, and Pubmed database using the English key words “bronchiolar adenoma, ciliated muconodular papillary tumor,” respectively patients with comprehensive clinical data were gathered, and studies from January 2002 to August 2021 that were relevant to the patients were examined. Results: A total of 35 articles and 71 instances were found, including 3 cases in our hospital, for a total of 74 cases. There were 31 males and 43 females among them, ranging in age from 18 to 84 years (average 63 years), and 15 cases had a smoking history. The majority of them were discovered by physical examination and had no clinical symptoms. The majority of the imaging revealed solid nodules with variable forms, with some ground-glass nodules displaying vacuole and bronchial inflation signs. BA/CMPT are generally gray-white, gray-brown solid nodules with obvious boundaries but no envelope with a maximum dimension of 4 to 45 mm (average 10.6 mm) on gross examination. Acinar, papillary, and lepidic formations can be seen under the microscope at high magnification; the majority of these structures are made up of tripartite epithelial components, including basal cells, mucous cells, ciliated columnar cells, and alveolar epithelial cells, demonstrating a variety of combinations. An important basis for diagnosis in immunohistochemistry is the continuous positive basal cell layer that is shown by p63, p40, and CK5/6. BRAF and epidermal growth factor receptor are the genes that are most frequently mutated. All of the patients showed no signs of metastasis or recurrence during follow-up period. Conclusion: BA/CMPT is a rare benign tumor of lung epithelium. Because imaging and intraoperative cryosection diagnosis are easy to be misdiagnosed as malignant, it is necessary to further improve understanding and improve immunohistochemistry and genetic examination.