AIM: In this study, we aimed to investigate the characteristics of metachronous second primary lung cancer (MSPLC) and the differences between primary lung cancer (PLC) and metachronous lung cancer.
MATERIALS AND METHODS: Patients diagnosed with lung cancer between January 2014 and December 2016 were retrospectively studied. MSPLC tumor cases and a new diagnosis of PLC were evaluated. Clinical, radiological, and demographic findings of the two groups, previous histopathologic diagnosis of MSPLC, histopathologic diagnosis of lung cancer in both groups, stages of treatment, and treatment history were recorded. All data were analyzed using the Chi-square, t-test, Kaplan–Meier, and Log-rank method. In all tests, P < 0.05 was considered statistically significant.
RESULTS: There were 53 (16.1%) cases in MSPLC group and 277 (83.9%) cases in the PLC group. There were no statistically significant differences between clinical, radiological, and demographic findings, cancer histopathologies, tumor stages, oncological, and surgical treatment characteristics of the cases (P > 0.05). The most frequent primary cancers were laryngeal carcinoma (11 cases) in the MSPLC group, with higher age (64 and 61, P = 0.01, respectively). Tumor size was smaller (44 mm and 52 mm, respectively) than the PLC group (P = 0.03). All other characteristics of both groups (P > 0.05) and survival were similar (15 months and 17 months, P = 0.87, respectively).
CONCLUSION: Among the lung cancers diagnosed in our clinic, 16% were detected as MSPLC. MSPLC group were older than the PLC group and tumor size is lower than the PLC group. There was no significant difference in treatment options and survival between the two groups.