Efficacy and prognosis analysis of surgical treatment for bilateral synchronous multiple primary non-small cell lung cancer.

Purpose: To explore the efficacy of surgical treatment for bilateral synchronous multiple primary non-small cell lung cancer (NSCLC), and to analyze the factors affecting prognosis. Methods: A total of 95 patients with bilateral synchronous multiple primary NSCLC operated in our hospital from January 2010 to December 2015 were retrospectively collected and analyzed. All lesions were resected by radical surgery with clear pathological diagnosis and stages based on the improved Martini-Melamed diagnostic criteria. Overall survival (OS) and recurrence-free survival (RFS) of the patients were calculated by the Kaplan-Meier method. After that, univariate analysis was performed for age, gender, tumor size, surgical methods, pathological T (pT) stage, N (pN) stage and postoperative adjuvant radiotherapy and chemotherapy, and multivariate analysis was carried out for prognosis using the Cox proportional hazards regression model. Results: Among the 95 patients, 20 patients (21.1%) were treated with multiple lobectomies, 58 (61%) with lobectomy+ sublobectomy, and 17 (17.9%) with multiple sublobectomies. Besides, 42 patients (44.2%) had maximum tumor diameter s2 cm. In postoperative pT staging, there were 28 patients (29.5%) in T1 stage, 53 (55.8%) in T2a stage, 3 (3.2%) in T2b stage, 6 (6.3%) in T3 stage and 1 (1.1%) in T4 stage. Additionally, 81 patients (85.3%) had no lymph node metastasis, 4 (4.2%) had N1 stage and 10 (10.5%) had N2 stage. All the 95 patients were followed up for 39-110 months, during which 12 (12.6%) patients died and 27 (28.4%) developed tumor recurrence or progression. The OS and the 5-year RFS were 87.4% and 72.4%, respectively. Univariate analysis revealed that the OS and RFS were not related to age, gender, smoking, surgical method, tumor number, but notably correlated with the maximum diameter of the tumor, the highest pT stage and lymph node metastasis. Multivariate analysis showed that the highest pT stage was independent factor affecting the OS and RFS of patients and lymph node metastasis was independent factor affecting RFS after operation. Patients with lower highest pT stage and lymph node metastasis achieved longer RFS (p=0.002, p=0.03, respectively). Conclusions: Surgical treatment of bilateral synchronous multiple primary NSCLC can raise the postoperative survival rate. The highest pT stage and lymph node metastasis are independent factors influencing the patient postoperative RFS, and the highest pT stage is independent factor influencing the postoperative OS, Adequate surgical resection and thorough lymph node dissection should be carried out as far as possible to accurately judge the prognosis.