Treatment package time predicts cancer-specific survival and distant metastasis in laryngeal cancer

We investigated whether treatment package time was significantly associated with survival outcomes of resectable locally-advanced laryngeal squamous cell carcinoma in patients who consecutively underwent various treatments, including surgery alone and salvage surgery for residual tumor. A total of 100 patients with clinical T3-T4 resectable laryngeal squamous cell carcinoma were enrolled in this study. The treatment package time was calculated in days between the start of any treatment and the end of all treatments, including postoperative radiotherapy and salvage surgery for residual tumors. Using a log-rank test, a treatment package time of ≥68 days showed significantly shorter cancer-specific (P=0.0013) and distant metastasis-free survival (P=0.0017), compared with a treatment package time of <68 days. Multivariate survival analyses of two Cox's hazards proportional models was conducted. In both model-1, which adjusted for cT3/cT4, cN0-1/cN2-3 and total laryngectomy/non-total laryngectomy, and model-2, which adjusted for cT3/cT4, cN0-1/cN2-3 and induction therapy/non-induction therapy, the cancer-specific survival and distant metastasis-free survival, according to treatment package time, were significantly longer with <68 days compared with ≥68 days (P<0.01). The present study demonstrated that a prolonged treatment package time is a prognostic factor for shorter cancer-specific and distant metastasis-free survival after various treatments for resectable locally-advanced laryngeal cancer.