Occult prostate cancer detected by hyoid bone metastasis after resection of thyroglossal duct cyst.

Metastatic carcinoma involving the hyoid bone has rarely been mentioned in the literature. The most frequent malignant lesion involving the hyoid bone metastasized from the larynx, followed by the vallecula and pyriform sinus. The authors report a unique case of occult prostate cancer that presented with an anterior midline neck mass diagnosed as a thyroglossal duct cyst. Two foci of metastatic carcinoma lesions in the hyoid bone were detected after Sistrunk's operation and occult prostate cancer was confirmed by immunohistochemical staining of prostate-specific antigen. Prostate cancer with metastasis to hyoid bone has not been described previously in the literature. The authors report this case which raises important pathological considerations for diagnosis. The unique presentation also reiterates the importance of prostate cancer bone metastasis.