[Tumor seeding to the neck through percutaneous applicators of interstitial high-dose-rate brachytherapy for cancer of the tongue: a case report].

We report the case of a 46-year-old woman with cancer of the tongue. She underwent interstitial high-dose-rate brachytherapy of 50 Gy in 10 fractions for 5 days following telecobalt therapy of 20 Gy in 10 fractions for 2 weeks. Seven applicators were percutaneously implanted into the tongue. Radical neck dissection was carried out because a tumor rapidly developed on the neck 2.5 months after the treatment. Pathological examination revealed tumor seeding to the soft tissue of the neck where applicators were placed. To the best of our knowledge, there have been no reports presenting tumor seeding through percutaneous applicators of interstitial brachytherapy for head and neck tumor.