Development a predictive nomogram for spontaneous pleurodesis in patients with non-small cell lung cancer and malignant pleural effusion

Background: Indwelling pleural catheter (IPC) insertion is associated with fewer subsequent procedures and higher rates of spontaneous pleurodesis (SP) in patients with malignant pleural effusion (MPE). However, long-term pleural drains may cause psychological and physical distress. Additionally, only a portion of patients can benefit from IPC insertion and ultimately have them removed. The nomogram reflects the influence of different factors on outcome visually, enabling clinics to assess the optimal population. Thus, the objective of this study was to develop and validate a novel nomogram to predict successful SP in non-small cell lung cancer (NSCLC) patients with MPE treated with IPC. Methods: We reviewed data on the use of IPC insertion for MPE in patients with NSCLC and allocated them randomly to development (60%) and validation (40%) sets. A static and dynamic nomogram was developed based on multivariate logistic regression to evaluate SP occurrence in the development set. Receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and Nelson-Aalen cumulative risk curves were used to validate the predictive accuracy of the nomogram. Results: In total, 331 patients (development set: n=199; validation set: n=132) were selected for this study. Medical thoracoscopy, septated effusion, and effusion volume were the strongest predictors of SP. Other predictors included gender, systemic treatment, and serum neutrophil-to-lymphocyte ratio. The prediction nomogram was demonstrated good predictive ability in the development and validation sets (area under the curve: 0.745 and 0.720, respectively). The DCA indicated that the model had a certain clinical application value. Nelson-Aalen cumulative risk curves showed that the more favorable group received successful SP than did the less favorable group (P<0.001). Conclusions: We developed an accurate and practicable nomogram for successfully predicting SP. These results may benefit clinicians in optimizing treatment decisions, improving the probability of SP, and relieving the long-term discomfort caused by IPC.