Late Breaking Abstract - Surgical Outcomes of Synchronous Multiple Primary Lung Cancers With More Than Three Lesions

<bold>Background:</bold> Surgery remains the mainstay of treatment for synchronous multiple primary lung cancers (SMPLC). We summarized and analyzed the clinical characteristics and surgical outcomes of patients with ≥ 3 lesions who underwent surgical resection. <bold>Methods:</bold> Clinical characteristics and survival outcomes of SMPLC patients with ≥ 3 lesions who underwent surgical resection in West China hospital, Sichuan University from January 2009 to December 2018 were retrospectively reviewed. <bold>Results:</bold> One hundred and three patients were included. The majority were female (78.6%, 81/103) and never-smokers (85.4%, 88/103). A total of 367 tumors were resected, 80.7%(296/397) were GGN lesions and 19.3%(71/397) were solid lesions. There were 360(98.1%) LUAD and 7(1.9%) LUSC tumors, respectively. Sixty-five and 38 patients respectively underwent single-stage and two-stage surgical resection. The surgical procedure was mainly lobar combined with sublobar resection (53.4%) and multi-sublobar resection (44.7%), and no severe postoperative complications or deaths occurred. The 1,3 and 5-year OS rate were 100.0%, 96.1% and 93.5%, respectively. There were no significant differences in survival prognosis between patients received single-stage and two-stage surgery (p=0.867). Cox logistic regression analysis showed that presence of smoking history and presence of lymph node metastasis were independent risk factors for survival prognosis. <bold>Conclusion:</bold> For SMPLC with ≥ 3 lesions, radical surgery can yield satisfactory prognosis. One-stage surgery may be safe and feasible. Smoking history and lymph node metastasis can help to predict the prognosis of patients with SMPLC after surgery.