A cause-specific Cox model for second primary tumors in patients with head and neck cancer: A RONCDOC study.

BACKGROUND: The aim of this study was to identify risk factors for the development of second primary tumors (SPTs) in the head and neck region, lungs, and esophagus in patients with head and neck cancer. METHODS: We collected data from 1581 patients. A cause-specific Cox model for the development of an SPT was fitted, accounting for the competing risks residual/recurrent tumor and mortality. RESULTS: Of all patients, 246 (15.6%) developed SPTs. Analysis showed that tobacco and alcohol use, comorbidity, and the oral cavity subsite were risk factors for SPTs. The C-index, the discriminative accuracy, of the model for SPT was 0.65 (95% confidence interval, 0.61-0.68). CONCLUSIONS: Our results show that there is potential to identify patients who have an increased risk to develop an SPT. This might increase their survival chances and quality of life. More research is needed to provide head and neck clinicians with definitive recommendations.

Survival of patients with head and neck cancer with metachronous multiple primary tumors is surprisingly favorable.

BACKGROUND: The objectives of this study are to determine the incidence and survival rate of patients with head and neck squamous cell carcinoma (HNSCC) with multiple primary tumors (MPT) in the HN-region, lung, or esophagus. METHODS: Patient and tumor specific data of 1372 patients with HNSCC were collected from both the national cancer registry and patient records to ensure high-quality double-checked data. RESULTS: The total incidence of MPTs in the HN-region, lung, and esophagus in patients with HNSCC was 11% (149/1372). Patients with lung MPTs and esophageal MPTs had a significant worse 5-year survival than patients with HN-MPTs (29%, 14%, and 67%, respectively, P < 0.001). The 5-year survival rate for synchronous HN MPTs was only 25%, whereas it was surprisingly high for patients with metachronous HN MPT (85%, P < 0.001). CONCLUSIONS: One of 10 patients with HNSCC develop MPTs in the HN-region, lung, or esophagus. The 5-year survival of patients with metachronous HN MPTs was surprisingly favorable.