Prognostic nomograms for overall and cancer-specific survival in individuals with large cell neuroendocrine...

Large cell neuroendocrine carcinoma (LCNEC) is a rare and aggressive subtype of pulmonary malignancy, for which prognostic assessment remains challenging due to limited predictive models. This study aimed to develop and validate prognostic nomograms for estimating overall survival (OS) and cancer-specific survival (CSS) in individuals diagnosed with LCNEC.

A total of 613 patients confirmed to have LCNEC between 2010 and 2015 were selected from the Surveillance, Epidemiology and End Results (SEER) database. They were further divided into a training cohort and a validation cohort. The discrimination and calibration of the nomogram were evaluated using concordance index (C-index), area under time-dependent receiver operating characteristic curve [time-dependent area under the curve (AUC)], and calibration plots. The calibration curves were constructed to assess the consistency between predicted and observed outcomes. Decision curve analysis (DCA) was performed to evaluate the clinical utility of the nomograms across different probability threshold.

Six variables were selected to establish the nomogram for LCNEC. The C-index (0.732 for the validation cohort) and the time-dependent AUC (>0.7) indicated satisfactory discriminative ability of the nomogram. The calibration plots showed favorable consistency between the prediction of the nomogram and actual observations in both the training and validation cohorts. Furthermore, DCA showed that the nomogram was clinically useful to recognize patients at high risk.

The prognostic nomograms developed in this study incorporate key clinical and pathological variables, including sex, radiotherapy, surgery, T stage, N stage, and brain metastasis status, to provide individualized estimates of OS and CSS in individuals with LCNEC. These models offer a practical tool for risk stratification and may support more personalized treatment planning in clinical practice.