Background: With the popularization of high-resolution computed tomography (HRCT), the detection rate of synchronous multiple primary lung cancer (SMPLC) is increasing. We retrospectively analyzed the surgical results of SMPLC patients in our hospital to determine the best treatment for SMPLC.Methods: A total of 90 SMPLC patients met the diagnostic criteria underwent complete resection and lymph node dissection or sampling without any preoperative induction therapy in the Department of Thoracic Surgery, Qilu Hospital, Cheeloo College of Medicine, Shandong University. We analyzed the postoperative survival rate, and further studied the relationship between survival rates and sex, age, preoperative symptoms, tumor location, tumor number, tumor size, surgical type, surgical frequency, histopathologic types, vascular infiltration, visceral pleural invasion and postoperative therapy.Results: Among 90 patients, the 1- and 3-year disease free survival (DFS) rates were 97.0% and 76.7% while the 1- and 3-year overall survival (OS) rates were 98.81% and 82.35%. Vascular infiltration (HR=402.46, p=0.005) and postoperative chemotherapy (HR>1000, p<0.001) were independent risk factors for DFS, while only postoperative chemotherapy (HR=184.10, p=0.002) was an independent risk factor for OS.Conclusions: First, SMPLC is different from intrapulmonary metastasis and its clinical stage is also different from the 8th (2015) edition TNM classification for lung cancer. Second, when pulmonary function permits, surgery (complete resection and lymph node dissection) is a significantly beneficial treatment for patients with SMPLC. Third, for early stage SMPLC patients, vascular infiltration and postoperative chemotherapy are harmful to the survival.

Background: With the popularization of high-resolution computed tomography (HRCT), the detection rate of synchronous multiple primary lung cancer (SMPLC) is increasing. We retrospectively analyzed the surgical results of SMPLC patients in our hospital to determine the best treatment, surgical prognosis and survival analysis.Methods: A total of 78 SMPLC patients met the diagnostic criteria underwent complete resection and lymph node dissection or sampling without any preoperative induction therapy in the Department of Thoracic Surgery, Qilu Hospital, Cheeloo College of Medicine, Shandong University. We analyzed the postoperative survival rate, and further studied the relationship between survival rates and sex, age, preoperative symptoms, tumor location, tumor number, tumor size, lymph node metastasis, TNM stage, surgical type, surgical frequency, histopathologic types, vascular infiltration, visceral pleural invasion and postoperative therapy.Results: Among 78 patients, the 1-,2-,3-,4- and 5-year disease free survival (DFS) rates were 93.42%, 86.84%, 77.78%, 62.96%, and 60.00%, respectively, while the 1-,2-,3-,4- and 5-year overall survival (OS) rates were 94.73%, 92.11%, 82.22%, 77.78%, and 65.00%, respectively. TNM stage of the largest tumor (II:HR=7.40,III:9.01,p=0.002) was an independent risk factor for DFS. Smoking history (HR=4.34,p=0.039) and TNM stage of the largest tumor (II:HR=9.38,III:9.42,p=0.003) were independent risk factors for overall survival.Conclusions: First, SMPLC is different from intrapulmonary metastasis and its clinical stage is also different from the 8th (2015) edition TNM classification for lung cancer. Second, when pulmonary function permits, surgery (complete resection and lymph node dissection) is a significantly beneficial treatment for patients with SMPLC. Third, TNM stage of the largest tumor (II:HR=7.40,III:9.01,p=0.002) was an independent risk factor for DFS. Smoking history (HR=4.34,p=0.039) and TNM stage of the largest tumor (II:HR=9.38,III:9.42,p=0.003) were independent risk factors for overall survival.