The role of total parotidectomy for metastatic cutaneous squamous cell carcinoma and malignant melanoma

IMPORTANCE: Metastatic cutaneous malignancies of the head and neck, including cutaneous squamous cell carcinoma (cSCC) and malignant melanoma (MM), are aggressive cancers frequently involving the parotid-area lymph nodes (LNs). In such cases, controversy exists about the extent of surgical resection, with many centers choosing not to remove the parotid deep lobe LNs. OBJECTIVES: To determine patterns of intraparotid and neck metastasis, to identify risk factors, and to report outcomes in patients with parotid superficial lobe LN metastasis from cSCC and MM. DESIGN, SETTING, AND PARTICIPANTS: We retrospectively reviewed 65 adults from Mayo Clinic in Minnesota who underwent total parotidectomy and neck dissection formetastatic cSCC (n = 42) orMM(n = 23) involving the parotid superficial lobe. INTERVENTIONS: Total parotidectomy and neck dissection. MAIN OUTCOMES AND MEASURES: The presence and number of parotid deep lobe and neck LNs involved with metastatic disease were assessed. Risk factors associated with metastatic spread to the parotid deep lobe were identified, and patient outcomes are reported. RESULTS: Eleven of 42 patients with cSCC (26%) and 3 of 23 patients withMM(13%) metastatic to the parotid superficial lobe also had parotid deep lobe metastasis. Thirteen of 42 patients with cSCC (31%) and 6 of 23 patients withMM(26%) had positive cervical LN metastasis. Among all patients, 22%(14 of 65) had metastasis to the parotid deep lobe, and 29% (19 of 65) had metastasis to cervical LNs. By univariate analysis, neck metastasis and N2 neck disease were risk factors formetastatic cSCC spread to the parotid deep lobe. Parotid-area local control was excellent in patients with metastatic cSCC (93%[39 of 42]) andMM(100% [23 of 23]). Long-term survival remains poor because distant metastases are common. CONCLUSIONS AND RELEVANCE: Metastatic cSCC andMMto the parotid superficial lobe also involve LNs in the parotid deep lobe and neck in a significant and almost equal number of patients. Parotid deep lobe metastasis from cutaneous malignancies portends a poor prognosis. Therefore, patients with superficial parotid gland metastasis should be considered for management with not only neck dissection and adjuvant therapy but also deep lobe parotidectomy.