Implantation metastasis of head and neck cancer after fine needle aspiration biopsy

One possible complication of the aspiration biopsy of malignant tumors is dissemination of tumor cells along the needle track. However, a search of the literature revealed few definite reports of implantation metastases of head and neck tumors after fine needle aspiration biopsy (FNAB). Here we report two cases of skin metastasis of head and neck cancer after FNAB, including a patient with papillary adenocarcinoma of the thyroid and one with adenoid cystic carcinoma of the submandibular gland. Surgical treatment prevented the spread of the tumor in both cases and there have been no evidence of recurrence to date. This report should alert head and neck surgeons to the possibility of implantation metastasis after FNAB.