Secondary malignant tumors of the parotid gland: not a secondary problem!

PURPOSE To present the clinical features of patients with parotid gland metastasis, and compare the results with previously published series. Most of the relevant literature arises from case reports, while there are only few series reported, as secondary neoplastic lesions of the parotid gland are uncommon. METHODS The medical records of patients with parotid gland metastasis, treated at the ENT Department of the University Hospital of Ferrara, between January 1st 1965 and December 31th 2014, were retrospectively reviewed. Fine needle aspiration cytology (FNAC) and biopsy results were compared. Localization of the primary tumor was searched in all cases. Lymphomatous lesions have been excluded from the study. RESULTS A total of 66 patients with parotid gland metastasis were evaluated. There were 53 males and 13 females with mean age 68.2 ± 13.5 years. Histopathologic analysis of the lesions revealed that 47 (71.2%) were parotid gland metastasis from cutaneous head and neck tumors, 8 (12.1%) from the upper aero-digestive tract, 7 (12.1%) from locations out of facial-cervical region, 1 from a conjunctival melanoma, while in 3 (4.5%) cases the primary tumor origin remained unknown. FNAC results were compared with the final histopathologic diagnosis, showing an overall concordance of 71.9%. CONCLUSION The present study is one of the largest series of parotid gland metastasis available so far. During the diagnostic work-up of a parotid tumor, the possibility of a metastasis should also be considered. FNAC can be a useful tool for the preoperative assessment of parotid lesions.