Patterns of treatment failure in patients with sinonasal squamous cell carcinoma after chemoradiotherapy

To investigate the failure patterns based on precision radiation treatment and to determine the predictive factors of treatment failure for sinonasal squamous cell carcinoma (SNSCC) patients. This was a retrospective study that included 214 cases of treatment failure from 441 consecutive patients. Two experienced radiation oncologists evaluated the tumor volume of cases with local recurrence. The 5-year overall survival (OS), progression-free survival rates (PFS), and distant-metastasis-free survival (DMFS) were estimated. Investigations were performed on the factors that predicted local failure or distant metastasis. 140 (31.7%) patients developed local recurrence, 24 (5.4%) experienced regional failure, and 65 (14.7%) underwent distant metastasis. In-field, marginal, and out-of-field failures occurred in 55.7% (78/140), 33.6% (47/140), and 10.7% (15/140) of patients with local recurrence, respectively. In logistic regression analysis, factors statistically significant for total local failure included treatment mode (p