Le metastasi parotidee: revisione della letteratura e contributo casistico.

Parotid gland is an unusual metastasis site. Metastatic lesions very often represent spread from adjacent regions of lymphatic drainage; nevertheless direct involvement or hematogenous spread can occur. Head and neck cutaneous tumors are the most common primary: in a overlooking of more than 800 cases, cutaneous squamous cell carcinomas and melanomas represent about 80%. Parotid metastasis from extra-cutaneous head and neck tumors and distant primary are uncommon: in our review we found respectively 66 and 87 reports. In our experience, from 1968 to 1991, we observed 38 patients with metastatic involvement of the parotid gland. The primary were located as follows: 24 cutaneous head and neck tumors (15 SCC, 7 melanomas, 2 BCC), 10 extra-cutaneous supra-clavicular tumors (9 carcinomas, 1 adenocarcinoma), 4 distant primary (2 renal cell carcinomas, 2 lung tumors). In 14 patients was performed a parotidectomy, in 10 cases associated to a neck dissection and in 4 cases followed by post-operative radiotherapy. Exclusive radiotherapy and chemotherapy were performed respectively in 14 and 4 cases, in 6 patients the only planned treatment was a symptomatic therapy. After 1, 3 and 5 years follow-up the overall survival was respectively of 71.4%, 30.4% and 11.8%; better results were observed in cutaneous primary (86.3%, 42.8% and 20%). To conclude, parotid metastases represent a not uniform clinical entity. Cutaneous SCC, BCC and melanoma can be successfully treated by surgery and/or radiotherapy. As non-cutaneous secondary parotid tumors have a poor prognosis, treatment must be related to condition of generalized disease.