A rare case of rib chondrosarcoma with purely mesenchymal cells metastases to thyroid.

Metastasis to the thyroid gland is uncommon. The most common malignant tumors that metastasize to the thyroid gland include renal cell carcinoma, colorectal cancer, lung cancer, and breast cancer. Metastasis of chondrosarcoma to thyroid is extremely rare.We describe a rare case of rib chondrosarcoma metastases to the thyroid gland. We reviewed patient characteristics, histological presentations, treatments, time of recurrence on chondrosarcoma, and metastasis situation. Additionally, we review all English articles reporting cases of chondrosarcoma metastasis to the thyroid gland that have been published in Embase, PubMed, and ISI WEB of Science databases (1981-2023) in this paper.Only 7 cases of chondrosarcoma metastasis to the thyroid have been reported, including one report written in French. (Otmany et al. in Médecine Du Maghreb 53-54, 2001). We found that most patients are female adults, with compression signs or pain, most of whose metastases occurred after several years, and whom have poor prognoses. The main examinations are CT and ultrasound, the primary treatment is surgery, and the major pathological characteristic is coexistence of chondrocytes and mesenchymal cells.The case we describe here is the first report of mesenchymal chondrosarcoma metastasis to the thyroid gland with only pure mesenchymal cells and no chondrocytes. Moreover, these rare cases highlight the necessary of communication between radiologists, histopathologists, and clinicians. It is meaningful to acquaint previous malignant tumor for diagnosing the metastases to the thyroid gland.