Survival advantage of radiotherapy and nomogram for patients with pulmonary neuroendocrine neoplasms: a propensity score-matched Surveillance, Epidemiology, and End Results database study

Background: The standard treatment for pulmonary neuroendocrine neoplasms (pNENs) is surgery in the early stage and is generally determined according to the histologic type and stage. Radiotherapy (RT) is a treatment option for locally advanced or unresectable lung cancers. The aim of this study was to determine the prognostic value of RT in patients with pNENs using data from the Surveillance, Epidemiology, and End Results database. Methods: We used propensity score matching analysis to balance differences in variables between the RT and no-RT groups. Univariate and multivariate Cox proportional hazards regression analyses were used to evaluate the factors related to overall survival and cancer-specific survival (CSS). A novel nomogram was constructed, and the results were evaluated using the concordance index. Results: A total of 7,470 cases were identified between 2000 and 2019, among whom 1,429 were placed in the RT group and propensity-score matched with those in the no-RT group at a 1:1 ratio. Age, sex, marital status, disease extension, surgery, and RT were identified as independent prognostic factors of outcome. There was no significant difference in overall or CSS between RT and no-RT patients in the surgery group (P=0.22 and P=0.72, respectively). However, RT was associated with survival benefit in the no-surgery group. According to the concordance index, the nomogram could accurately predict the prognosis of patients with pNENs. Conclusions: Our findings indicate that RT may provide a survival benefit for patients with pNENs, particularly for those who did not undergo surgery. The nomogram produced in this study may be a used to predict the prognosis of this patient group.