Margin status, local control, and disease-specific survival in surgically resected parotid carcinomas with parapharyngeal extension.

ABSTRACT

BACKGROUND: Resection of parotid carcinomas involving the parapharyngeal space is challenging. How this affects tumor margin control, recurrence, and survival is unclear. METHODS: Patients who underwent resection of parotid carcinomas between 1985 and 2015 at Memorial Sloan Kettering Cancer Center were evaluated for the impact of parapharyngeal extension (PPE) on margin status, local recurrence-free probability (LRFP), and disease-specific survival (DSS). RESULTS: Out of 214 patients in whom preoperative imaging was available for review, 22 (10.3%) had PPE. Matched by histotypes, carcinomas with PPE had comparable margin positivity (p = 0.479), T classification (p = 0.316), pathologic risk (p = 0.936), and adjuvant therapy (p = 0.617) to those without PPE. The 3-year LRFP was 88.9% versus 95.4% (hazard ratio [HR] 2.23 after adjusting for pT classification, p = 0.342) and the 5-year DSS was 74.2% versus 69.5% (adjusted HR 0.45, p = 0.232) in patients with and without PPE. CONCLUSION: PPE does not appear to worsen oncologic outcomes in the resection of parotid carcinomas.