Clinical features of multiple lung cancers based on thin-section computed tomography: What are the appropriate surgical strategies for second lung cancers?

We investigated the proper surgical strategies for second lung cancers based on the findings of thin-section CT. We classified 59 patients with second lung cancers into two categories based on the thin-section CT findings. In the ground glass nodule (GGN) group (n = 29), the first and/or the second lung cancers showed a GGN on thin-section CT. In the Solid group (n = 30), both the first and second lung cancers showed a solid appearance. The overall 5-year survival rate after second surgery was 71.7 %. The univariate analyses revealed that the presence of more than three lung tumors was significantly more common in the GGN group. Regarding the surgical strategies, all the patients in the GGN group underwent limited resection for at least one of the operations, whereas 36 % of those in the Solid group underwent bilateral lobectomy. The 5-year survival in the GGN group (89.1 %) was significantly better than that in the Solid group (40.8 %) (p = 0.0305). Limited resection should be performed for GGN patients as much as possible to preserve lung function, due to the possible presence of more than three lung cancers. Despite the higher likelihood of having more tumors, the GGN patients had a better survival. In contrast, lobectomy for second lesions should be aggressively considered for solid tumor patients whenever possible.