Investigation of Second Primary Lung Malignancy Rates in Laryngeal Cancer Patients

Background: Laryngeal cancer (LC) accounts for 30-40% of head and neck malignancies and is the most common malignancy in the field of otolaryngology. The 5-year survival rate of LC is 70-80% in the early stages of the disease and 50% in the advanced stages. In this respect, its mortality is lower than many other types of cancer, but second primary malignancies (SPM) are significant mortality and morbidity factors for LC patients. The aim of this study is to gauge the SPM rates of LC patients and the changes in these rates according to different parameters. Methods: Five hundred fifty-six LC patients were included in the study, and the records of the patients were analyzed retrospectively. The patients' age and gender, details of smoking and alcohol consumption, localization of the tumor, tumour, node, metastasis stages, histological types, primary treatment options, SPM localizations, SPM's histological types, treatment options for SPM, dates, and causes of death were all determined, and the SPM rate changes according to these parameters were calculated. The overall survival time, disease-free survival time,1 and 5-year survival rates of SPM+ and SPM-patients, and survival rates according to SPM localization were also calculated. Results: The mean age was 59.38 +/- 10.18 (49.2-69.56), and SPM was detected in 49 patients (8.8%). The rate of SPM was significantly lower in glottic tumors (P = .001). Second primary malignancies rates were higher in T3-4 tumors, and there was a statistically significant difference with T3 tumors (P = .016). Significantly more SPM was detected in poorly differentiated tumors (P = .001). Second primary malignancies localization was pulmonary in 38 patients (77.55%). For patients with SPM, 1-year overall survival was 89.6%, and 5-year overall survival was 33.4%. For LC patients without SPM, 1-year overall survival was 89%, and 5-year overall survival was 67.8%. Conclusion: Our study showed that non-glottic LC carries a higher risk of SPM, which is consistent with the literature. In addition, we found that poorly differentiated squamous cell carcinoma of the larynx carries a higher risk of SPM development. No previous study could be located in the literature which shows a correlation between the risk of developing SPM according to the histological type of LC. However, a definite relationship between the parameters and the development of SPM can be determined in the studies carried out, which means that the survival rate can be increased significantly as risky patients can be identified at the primary treatment stage.