[Effects of TNM extension and histopathological type of the tumor on long-term survival rates of parotid and submandibular gland cancer].

The effects of TNM extension and histopathological type of the tumor on 5 and 10-year survival rates were analysed in 1,147 cases of parotid cancer and 271 cases of submandibular gland cancer which had been registered from 152 institutes throughout Japan since 1978. Advance of stage decreased the prognosis significantly, and the decrease was more pronounced in submandibular gland cancer. Facial paralysis also decreased the prognosis of parotid cancer significantly. The prognosis was also affected significantly by the histopathological type of the tumor. The 5-year survival rates of adenocarcinoma, epidermoid carcinoma and undifferentiated carcinoma were only about 30% in parotid cancer and about 20% in submandibular gland cancer. In treatment of salivary gland cancer, the therapeutic approach should be individualized in accordance with the tumor extension and its histopathological type. Improvement of accuracy in preoperative diagnosis of salivary gland cancer is of the utmost importance.