Surgical management of the facial nerve in the presence of malignancy about the face

Abstract

Approximately 5% of cutaneous squamous carcinomas demonstrate perineural spread (PNS) affecting, most frequently, the facial and trigeminal nerves. Cutaneous cancers demonstrating subclinical (histologic) PNS require postoperative radiotherapy after excision, whereas those cancers with clinical facial nerve invasion require more radical excision, removing nerve and parotid, followed by adjuvant irradiation. Local control rates vary with the extent of PNS—90% for minimal subclinical invasion, 60% for extensive invasion, and 50% when there is nerve dysfunction. Parotid cancers may also invade the facial nerve, and approximately 12 to 15% of patients with parotid malignancy have facial nerve dysfunction at presentation. These patients need radical parotidectomy and adjuvant radiotherapy, but they have a relatively poor prognosis—an approximately 45% chance of 10-year survival when nerve function is abnormal preoperatively. The extent of surgery for parotid cancer should be governed by tumor size and the macroscopic appearance of the facial nerve. Tumors less than 4 cm in diameter can usually be resected by limited parotidectomy, preserving the nerve; however, every effort should be made to achieve clear surgical margins. Adjuvant radiotherapy is recommended for large or high-grade tumors, positive margins, and perineural extension, because it improves local control. However, there may be little impact on survival.