Adenoid cystic carcinoma of the head and neck treated by surgery with or without postoperative radiation therapy: Prognostic features of recurrence

Purpose: This study sought to review a single-institution experience with the management of adenoid cystic carcinoma of the head and neck. Methods and Materials: Between 1960 and 2004, 140 patients with adenoid cystic carcinoma of the head and neck were treated with definitive surgery. Ninety patients (64%) received postoperative radiation to a median dose of 64 Gy (range, 54-71 Gy). Distribution of T stage was: 26% T1, 28% T2, 20% T3, and 26% T4. Seventy-eight patients (56%) had microscopically positive margins. Median follow-up was 66 months (range, 7-267 months). Results: The 5- and 10-year rate estimates of local control were 88% and 77%, respectively. A Cox proportional hazards model identified T4 disease (p = 0.0001), perineural invasion (p = 0.008), omission of postoperative radiation (p = 0.007), and major nerve involvement (p = 0.02) as independent predictors of local recurrence. Radiation dose lower than 60 Gy (p = 0.0004), T4 disease (p = 0.005), and major nerve involvement (p = 0.02) were predictors of local recurrence among those treated with surgery and postoperative radiation. The 10-year overall survival and distant metastasis-free survival were 64% and 66%, respectively. Conclusion: Combined-modality therapy with surgery followed by radiation to doses in excess of 60 Gy should be considered the standard of care for adenoid cystic carcinoma of the head and neck.