Prognostic Factors and Clinical Outcome in Parotid Gland Tumors: a Single Institution Experience from the Eastern Black Sea Region of Turkey

Abstract

Purpose: To review clinical characteristics, treatment outcomes and prognostic factors in patients with parotid gland tumors treated with surgery and postoperative radiotherapy.

Materials and methods: We retrospectively reviewed 69 patients with parotid gland tumors, with a median follow-up of 52 months (range, 2-228 months). and a median radiotherapy dose of 60Gy (range, 30-69 Gy).

Results: There were 24 (35%) females and 45 (65%) males, at a ratio of 1/1.9. Median age at presentation was 58.9±17.2 (range 13-88) years. The most common histology was adenoid cystic carcinoma (33%) and mucoepidermoid carcinoma (28%). The mean overall survival (OS) was 65.3±8 (95% confidence interval [CI], 49.6-81.1) months and the median overall survival was 40.0 ± 7 (95% CI, 26.2-53.7) months. The -1, -3, -5 and -10 year OS rates were 78%, 52.4%, 35.3% and 19.6% respectively. The mean disease free survival (DFS) was 79.2±10 (95% CI, 59.3-97.1) months and the median disease free survival was 38±13 (95% CI, 7.05-88.7) months. The -1,-3,-5 and -10 year DFS rates were 71.9%, 50.1%, 43.7% and 30.1% respectively. On univariate analysis, the OS was significantly better with female sex (p<0.005), < 50 age (p<0.021), T stage (p<0.0001), absence of lymph node involvement (p<0.0001), lower tumor grade (p<0.0001), absence of lymphovascular invasion (p<0.002), absence of perineural invasion (p<0.0001), absence of extracapsuler extension (p<0.0001), surgical margin negativity (p<0.006), ≤60 Gy radiotherapy dose (p<0.0001) and absence of distant metastasis (p<0.027).

Conclusions: Employing existing standards of postoperative radiotherapy is a possible treatment that was found to be mainly effective in patients with parotid gland carcinomas.