Analysis of risk factors and construction of a nomogram prediction model for early hemoptysis following 125I seed implantation in patients with advanced lung cancer

PURPOSE: I) seed implantation in patients with advanced lung cancer and to develop a nomogram-based prediction model. METHODS: I seed implantation at the Second Hospital of Tianjin Medical University between August 2023 and May 2025. Patients were divided into a hemoptysis group (n = 31) and a non-hemoptysis group (n = 102) based on the occurrence of postoperative hemoptysis. Clinical characteristics were compared between groups. Binary logistic regression was used to identify independent risk factors, and a nomogram prediction model was constructed. Model performance was evaluated using receiver operating characteristic (ROC) analysis, calibration curves, and decision curve analysis (DCA). RESULTS: Of the 133 enrolled patients, 31 (23.3%) developed postoperative hemoptysis. Logistic regression analysis identified right hilar lesion location [odds ratio (OR): 10.831, 95% confidence interval (CI): 2.537-46.232], history of chemotherapy (OR: 3.138, 95% CI: 1.160-8.488), and intrathoracic bleeding (OR: 2.666, 95% CI: 1.016-6.993) as independent risk factors. Prothrombin time (PT) showed a negative correlation in the multivariate analysis (OR: 0.507, 95% CI: 0.280-0.918). However, as both sets of values fall within the normal range and the difference is minimal, the clinical significance is limited, and the results should be interpreted with caution. The nomogram demonstrated good discriminative ability, with an area under the ROC curve of 0.830 (95% CI: 0.753-0.907). At a cutoff probability of 0.155, the model achieved a sensitivity of 93.5% and a specificity of 65.7%. Calibration analysis showed good agreement between predicted and observed outcomes, and DCA indicated significant net clinical benefit across a threshold probability range of 0.02-0.70. CONCLUSIONS: I seed implantation in advanced lung cancer. The proposed nomogram demonstrates favorable predictive performance and may help identify patients at high risk early, guiding preventive strategies. CLINICAL SIGNIFICANCE: This nomogram enables early post-procedural identification of high-risk patients, particularly those with right hilar lesions, and its high sensitivity supports its use as a screening tool to guide preventive hemostatic strategies.