Prognostic value of a three-grade classification in primary epithelial parotid carcinoma: result of a histological review from a 20-year experience of total parotidectomy with neck dissection in a single institution

Abstract

Background: The tumour grading of primary parotid cancers (PPCs) remains controversial.

Methods: A 20-year standardised single centre treatment has been assessed retrospectively. The histological review of 155 consecutively treated parotid malignancies identified 96 suitable cases for univariate and multivariate survival analyses.

Results: Treatment involved total parotidectomy, neck dissection and post-operative radiotherapy in, respectively, 91.7%, 83.3% and 70.4% of cases. The 5-year overall survival, disease-specific and recurrence-free survival rates were 79.4%, 83.5% and 70.8%, respectively. Univariate analysis confirmed the classical prognostic factors, i.e. age>60 years, male gender, facial palsy, hardness of the tumour, clinical stage, tumour grade, facial nerve invasion and lymph node metastases. Multivariate analysis identified a three-grade classification just after the clinical stage as the most important prognostic factor.

Conclusion: This study identifies the prognostic significance of intermediate grade tumours.