1
Introduction
The parotid gland harbors 85% of all salivary gland neoplasms. Though the majority of tumors are benign, complete surgical resection remains the mainstay of treatment. Along with adequate tumor removal, facial nerve preservation is a critical objective. Given the significant negative effects on quality of life following facial nerve sacrifice , every effort should be made to spare the nerve until conclusive evidence mandates its removal. Here we share observations from a case where facial nerve sacrifice was considered, but ultimately deferred due to lack of definitive intraoperative pathologic diagnosis.
2
Case report
A 71-year-old female with a history of diabetes, hypertension, and dementia presented with 6 weeks of left parotid swelling and tenderness. She had a previous parotidectomy in 2009 for a 1.1 cm lesion. On MRI, the 2009 lesion was ovoid and well-defined, with intermediate signal intensity on T1 and slight hyperintensity on T2. Imaging characteristics were not entirely consistent with the most likely diagnosis, pleomorphic adenoma, as these are usually brightly hyperintense on T2 sequences . Low-grade mucoepidermoid carcinoma and Warthin’s tumor were also considered. In the operating room, a 1 cm lymph node was removed from within the left deep parotid lobe, thought to be consistent with the imaging location. Final pathology revealed a benign lymph node. The patient was lost to follow-up.
The patient returned in 2016 with parotid swelling and tenderness. MRI revealed a 3.5 cm left-sided deep lobe parotid mass ( Fig. 1 ). The lesion was mobile and non-tender, without evidence of cervical lymphadenopathy. House-Brackmann score was 1/6 bilaterally. Fine needle aspiration (FNA) revealed cells suspicious for high-grade mucoepidermoid carcinoma. She was consented for revision parotidectomy with possible facial nerve sacrifice; however, she and her family were explicit about the desire to not sacrifice facial function. Intraoperative findings revealed the facial nerve to be densely adherent to the mass, preventing dissection. Frozen section analysis of a superior lymph node and tissue overlying the facial nerve was read as highly suspicious for myoepithelial carcinoma, but still inconclusive. The mass was incised for additional frozen analysis, which was also inconclusive. A permanent specimen was removed from inside the mass. As the mass could not be definitively identified as malignant, the decision was made to wait for permanent section results and forego tumor resection because facial nerve sacrifice would be necessary. Permanent pathology provided a final diagnosis of an infarcted Warthin’s tumor, eliminating the need for further surgical intervention.
