Prognostic factors in postoperative radiotherapy in salivary gland carcinoma: A single institution experience from Turkey.

BACKGROUND

We reviewed clinical characteristics, treatment outcomes, local and distant failure and prognostic factors in patients with salivary gland carcinoma treated with surgery and postoperative radiotherapy.

MATERIALS AND

METHODS

We retrospectively reviewed 75 patients with salivary gland cancer. 69 (%92) patients had cancer of the parotid gland, 3 (%4) patients had cancer of the submandibular gland and 3 (%4) patients had cancer of the minor salivary gland. 4 patients underwent postoperative chemoradiotherapy and 71 patients underwent postoperative radiotherapy. Median radiotherapy dose was 60Gy (range, 30Gy to 69Gy).

RESULTS

Median age was 59.6±17.9 (13-88) and the female/male ratio was 1/1.7. Median follow-up 52 months (2-228 months). The mean overall survival 69.2±8 (95%confidence interval[CI], 53.4-85.1) months. The 1-,3-,5- and 10- year overall survival rates were 79.8%, 53.2%, 37.4% and 22.8% respectively. The mean disease free survival 79.7±10 (95%CI, 60.1-99.3) months. The 1-,3-,5- and 10- year disaese free survival rates were 72.8%, 51.9%, 44.1% and 30.4% respectively. On multivariate analysis, the OS was significantly better for the female sex (hazard ratio[HR]:3,0;95%CI:1.5-5.6;P=0.001), absence of lymph node involvement ([HR]:3,0;95%CI:1.7-5.3;P=0.0001), lower tumor grade ([HR]:25,7;95%CI:3.3-199.3;P=0.002), negativity of the surgical margin ([HR]:2,3;95%CI:1.3-4.2;P=0.005), absence of lymphovasculer invasion ([HR]:2,6;95%CI:1.5-4.6;P=0.001), absence of extracapsuler extension ([HR]:6,5;95%CI:2.2-19.1;P=0.001), absence of perineural invasion ([HR]:4,8;95%CI:2.6-8.7;P=0.0001) and ≤60Gy radiotherapy dose ([HR]:3,1;95%CI:1.7-5.5;P=0.0001). They observed local recurrens in17 (23%) patients and distant metastasis in 33 (44%) patients.

CONCLUSIONS

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