Natural History of Pulmonary Subsolid Nodules: A Prospective Multicenter Study

• Published in: Journal of thoracic oncology Vol. 11; no. 7; pp. 1012 - 1028
• Main Authors: Kakinuma, Ryutaro, Noguchi, Masayuki, Ashizawa, Kazuto, Kuriyama, Keiko, Maeshima, Akiko Miyagi, Koizumi, Naoya, Kondo, Tetsuro, Matsuguma, Haruhisa, Nitta, Norihisa, Ohmatsu, Hironobu, Okami, Jiro, Suehisa, Hiroshi, Yamaji, Taiki, Kodama, Ken, Mori, Kiyoshi, Yamada, Kouzo, Matsuno, Yoshihiro, Murayama, Sadayuki, Murata, Kiyoshi
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.07.2016; Copyright by the International Association for the Study of Lung Cancer
• Subjects: Aged; Computed tomography; Female; Ground-glass nodule; Humans; Lung adenocarcinoma; Lung Neoplasms - diagnostic imaging; Lung Neoplasms - pathology; Lung Neoplasms - surgery; Male; Middle Aged; Natural history; Prospective Studies; Solitary Pulmonary Nodule - diagnostic imaging; Solitary Pulmonary Nodule - pathology; Solitary Pulmonary Nodule - surgery; Subsolid nodule; Tomography, X-Ray Computed; Subsolid nodule; Lung adenocarcinoma; Ground-glass nodule; Computed tomography; Natural history
• DOI: 10.1016/j.jtho.2016.04.006
• ISSN: 1556-0864; 1556-1380

The purpose of this study was to evaluate the natural course of the progression of pulmonary subsolid nodules (SSNs). Eight facilities participated in this study. A total of 795 patients with 1229 SSNs were assessed for the frequency of invasive adenocarcinomas. SSNs were classified into three categories: pure ground-glass nodules (PGGNs), heterogeneous GGNs (HGGNs) (solid component detected only in lung windows), and part-solid nodules. The mean prospective follow-up period was 4.3 ± 2.5 years. SSNs were classified at baseline as follows: 1046 PGGNs, 81 HGGNs, and 102 part-solid nodules. Among the 1046 PGGNs, 13 (1.2%) developed into HGGNs and 56 (5.4%) developed into part-solid nodules. Among the 81 HGGNs, 16 (19.8%) developed into part-solid nodules. Thus, the SSNs at the final follow-up were classified as follows: 977 PGGNs, 78 HGGNs, and 174 part-solid nodules. Of the 977 PGGNs, 35 were resected (nine minimally invasive adenocarcinomas [MIAs], 21 adenocarcinomas in situ [AIS], and five atypical adenomatous hyperplasias). Of the 78 HGGNs, seven were resected (five MIAs and two AIS). Of the 174 part-solid nodules, 49 were resected (12 invasive adenocarcinomas, 26 MIAs, 10 AIS, and one adenomatous hyperplasia). For the PGGNs, the mean period until their development into part-solid nodules was 3.8 ± 2.0 years, whereas the mean period for the HGGNs was 2.1 ± 2.3 years (p = 0.0004). This study revealed the frequencies and periods of development from PGGNs and HGGNs into part-solid nodules. Invasive adenocarcinomas were diagnosed only among the part-solid nodules, corresponding to 1% of all 1229 SSNs.