Objectives: Ciliated muconodular papillary tumor (CMPT) is a rare peripheral lung tumor and is a subtype of bronchial adenoma (BA). Although recent studies have suggested that BA is a neoplastic disease, the complete histogenesis of BA is not fully understood and molecular data are limited.
Methods: We examined the clinicopathological features of four patients with BA and performed immunohistochemical analysis and next-generation sequencing to characterize the molecular features of BA. A review of the previous literature was also undertaken to comprehensively conclude the molecular characteristics of this disease.
Results: From previous studies and the present study, 99 BA /CMPT cases have been reported to date, with most of the patients from East Asia (77/99, 77.8%). The median age was 64 years old and the ages ranged from 19 to 84 years. The proportion of males and females was close, being approximately 1:1.3. From the computed tomography images, the BA /CMPT tumor usually presented as a peripheral solid mass, part-solid nodules, or ground-glass opaque with an irregular border and occasional central cavities. ERBB2, EGFR, BRAF, and AKT1 mutations were found on the computed tomography images of the BAs. To the best of our knowledge, this is the first study to report about ERBB2 exon 20 insertion in BA.
Conclusion: BA /CMPT is a rare pulmonary disease that mainly affects elderly Asian patients. Many abnormal molecular changes were found, which confirmed the neoplastic nature of BA /CMPT. However, it also added to the debate regarding the biological behavior of BA /CMPT.