Analysis of prognostic risk factors and treatment of parotid cancer.

The aim of this study was to investigate the prognostic factors and therapeutic efficacy of parotid cancer (PC). A total of 135 patients with PC who received surgical treatment were recruited between January 1985 and January 2000. There were 47 patients with poorly differentiated PC and 88 with well-differentiated PC. In addition, PC of stage I, II, III and IV were found in 25, 47, 45 and 18 patients, respectively. Elective and therapeutic neck dissection was carried out in 46 and 39 patients, respectively, and 58 patients received post-operative radiotherapy. The Kaplan-Meier method was employed for survival analysis. The 5- and 10-year survival rates were 74.0 and 56.4%, respectively. A significant difference in the survival rates was observed between patients with poorly differentiated PC and those with well-differentiated PC (χ(2)=5.72, P=0.016). Cox regression model analysis revealed that age, stage of PC, pathological grade of PC and post-operative radiotherapy were independent prognostic factors of PC. Early diagnosis, early treatment and post-operative radiotherapy may increase the survival rate of PC patients. Patients with PC should therefore receive neck lymph node dissection, the extent of which depends on the pathological grade of PC.