Major salivary gland tumors: treatment results and prognostic factors

A retrospective review of 133 patients with major salivary gland carcinomas treated between 1955 and 1981 is presented. The majority of cases (104) originated in the parotid gland. The most common histological type was mucoepidermoid carcinoma (39 cases). Tumor-free interval was longest for patients with acinic cell and mucoepidermoid carcinomas. In contrast, adenoid cystic carcinoma was poorly controlled, regardless of the form of treatment. Initial control of primary major salivary gland tumors was inversely related to the presence of disease at the surgical margins. In cases with microscopic or gross disease at the surgical margins, postoperative radiation therapy controlled the tumor locally in 18 of 26 patients (69%). Postoperative radiation therapy was generally used only in cases with high-grade histologies, advanced stages, or positive surgical margins. Of the patients treated with surgery alone, 53% achieved local control, as compared to 75% of the group which received postoperative radiation therapy. Although the difference was not statistically significant, we would have expected the combined therapy group to have a lower control rate due to more advanced disease. There was a low salvage rate (22%) and a high incidence of distant metastasis (60%) in recurrent cases. The data indicates that complete surgical resection results in the best local control, with or without adjuvant radiation. When the surgical margin is inadequate and re-excision not possible, adjuvant radiation therapy appears to have a role to optimize local control and survival.