The inclusion criteria are: the patients diagnosed with primary laryngeal carcinoma (ICD-10 number: C32.0-C32.9) by microscopic confirmation; the histopathological types revealed only squamous cell neoplasms (Histologic Type ICD-O-3: 8050-8089); the year of diagnosis was between 2004 and 2015; the patients who underwent surgical treatment with or without radiotherapy or chemotherapy. Based on the above inclusion criteria, the exclusion criteria are: the patients with not first primary tumor in the larynx; the patients had developed metastasis by the time of diagnosis; the patients who had missing survival data or survival time less than 3 months.