Postoperative radiation therapy for major salivary gland malignancies.

Between 1966 and 1982 there have been 46 patients treated with surgery plus post-operative radiation therapy for malignant tumors of salivary gland origin. The indication(s) for radiotherapy included positive margins (42%), advanced local tumor (37%), positive nodes (33%), or high grade histology (48%). Overall actuarial local control at 5 years was 73%, being 100% for T1, 83% for T2, 80% for T3, and 43% for T4. Actuarial survival at 5 years was 80% for T1, 83% for T2, 60% for T3, and 48% for T4. Patients with positive nodes (N+) did worse than those with negative nodes (No), with locoregional control and survival at 5 years being 58% vs. 83%, (P = 0.025) and 38% vs. 80% (P = less than .01), respectively. We found no need for contralateral neck treatment even for those with positive nodes. Also, to date, none of eight patients with adenoid cystic histology has failed locally, as opposed to three of eight failures in patients treated with surgery alone. We believe that post-operative irradiation provides excellent locoregional control for appropriate patients with malignant tumors of major salivary glands.