Abstract
The case of a 70-year-old woman with a poorly differentiated thyroid carcinoma and cutaneous needle tract implantation is reported. A fine-needle aspiration (FNA) biopsy for a thyroid nodule measuring about 2 cm in diameter with egg-shell calcification was performed, and the cytology was equivalent to class II. Three years after the FNA, the patient became aware of a cutaneous nodule in the left side of her neck. She regarded it as a senile wart. Three months later, a follow-up CT of the thyroid nodule showed mild growth, and on the same day, physical examination detected the cutaneous nodule measuring about 3 mm at the FNA needle insertion site of her neck. Left hemi-thyroidectomy and resection of the cutaneous nodule were performed. Both nodules showed the same histology, poorly differentiated thyroid carcinoma. The patient is well with no sign of recurrence 3 years after the operation. This appears to be the first case report of simultaneous resection of the primary lesion and cutaneous FNA needle tract implantation of poorly differentiated thyroid carcinoma in Japan. During follow-up of negative cytology of FNA of thyroid nodules, inspection and palpation of the FNA needle insertion site are important.
