Despite the aggressive pursuit of diagnostic and treatment modalities for lung cancer, the treatment outcomes are still not satisfactory, and even patients with surgically resectable non-small cell lung cancer (NSCLC) are often at considerable risk of suffering recurrence and/or death from lung cancer. Regarding the treatment of patients with locally advanced, resectable NSCLC, several retrospective and prospective studies have shown the significance of multimodality treatments with preoperative chemoradiotherapy and surgical treatment. However, no definitive treatment strategies for locally advanced NSCLC patients have yet been established. One of the reasons for the lack of established treatment strategies for patients with locally advanced NSCLC is considered to be the heterogeneity of the population, i.e., cT4N0, cT3-4N1 and cT1a-3N2 tumors are included in stage IIIA disease, and superior sulcus tumors (SSTs) are also included in this classification. With regard to SST, two representative prospective phase II trials indicated the efficacy of surgical treatment following concurrent radiation and chemotherapy. In a study conducted by the Southwest Oncology Group, 110 patients with superior sulcus NSCLC were treated with two cycles of cisplatin and etoposide concurrently with 45 gray (Gy) of radiation, followed by surgical treatment and two additional cycles of chemotherapy postoperatively. The response rate (RR) to the preoperative chemoradiotherapy was 86%, and 83 patients (76%) were able to undergo complete resection. A pathological complete response (CR) was observed in 61 patients (56%), and the five-year survival of all patients and those undergoing complete resection was 44% and 54%, respectively. A phase II study conducted by the Japan Clinical Oncology Group examined the safety and efficacy of preoperative concurrent chemoradiotherapy using mitomycin, vinblastin and cisplatin followed by surgical treatment. Seventy-six patients with SST were enrolled in this study, and all received chemotherapy using tw