Abstract:

Background and purpose: Multiple primary lung cancers (MPLC) is a rare entity, but recently there has been a gradual increase in the number of patients diagnosed with MPLC. The aim of this study is to investigate the diagnosis, treatment and prognosis of MPLC through analyzing the clinical data. Methods: Forty-one patients were diagnosed MPLC by Martini-Melamed criteria. Their clinicopathological data were retrospectively reviewed. Results: There were 3 patients with triple primary lung cancer and 38 patients with double primary lung cancer. There were 13 patients with synchronous MPLC, 26 patients with metachronous MPLC, 2 patients with synchronous and metachronous MPLC. Of 85 lesions, the surgical procedures were mainly lobectomy (78.8%, 67/85). Lesions (41.2%, 35/85) were frequently in right upper lobe. Pathological type was mainly adenocarcinoma (70.6%, 60/85), followed by squamous cell carcinoma (17.6%, 15/85). Of 60 adenocarcinoma specimens, the papillary predominant subtype was more common (50%, 30/60). Eighty percent (68/85) of the lesions were stage I. As to the initial cancer and repeated cancer, patients who shared the same pathological type (68.3%, 28/41) were more than the different (31.7%, 13/41), of which adenocarcinoma-adenocarcinoma was most common(82.1%, 23/28). Lesions located in contralateral lobes were in 37 patients (90.2%), and located in ipsilateral different lobes were in 4 patients (9.8%). The 2-year overall survival (OS) of them was 87.8%. Survival analysis showed that the prognosis of patients with same pathological type was better than patients with different pathological type (P=0.037), the prognosis of patients with no lymph node metastasis was better than patients with N1, N2 metastasis (P=0.02). Conclusion: Lesions in patients with multiple primary lung cancers are more frequently in the right upper lobes. The pathology type is mainly adenocarcinoma, of which the papillary predominant subtype was most common. Early diagnosis improves continuously, active treatment with operation can achieve better prognosis.

Key words: Multiple primary lung cancers, Triple primary lung cancer, Double primary lung cancer, Adenocarcinoma, Overall survival