Incidence of pulmonary non-epithelial tumors: 18 years' experience at a single institute.

Primary and metastatic non-epithelial tumors of the lung and pleura (NETs-LP) are presumed to represent a small proportion of pulmonary neoplasm, and their epidemiologic characterization is lacking. Moreover, classification of pulmonary mesenchymal tumor according to 'WHO Classification of Tumors of Lung and Pleura' (2004) is simple and necessary to give a supplementation like new 'WHO Classification of Tumors of Soft Tissue and Bone' (2013). Non-epithelial tumors of the lung and pleura diagnosed from January 1995 to April 2013 were retrospectively reviewed and classified in accordance with 'WHO Classification of Tumors of Soft Tissue and Bone' (2013). Of 681 cases represented in the study, smooth muscle tumor (13.1%) was most common, and tumor of uncertain differentiation (10.5%) and fibroblastic/myofibroblastic tumor (5.7%) were followed. Smooth muscle tumor (12.6%) was the common primary tumor, whereas chondrogenic or osteogenic tumor (21.6%) was common in metastatic ones. Pulmonary vascular sarcoma (n=15) was the most frequent primary pulmonary sarcoma with following synovial sarcoma (n=9) and malignant type of solitary fibrous tumor (n=9). This study is the first trial of epidemiologic investigation in Korea about NETs-LP, indirectly representing their incidence in Korea and northeast Asia, and we hope that this presentation offers guidance in further study of NETs-LP.