Primary leiomyosarcoma of the thyroid gland with prior malignancy and radiotherapy: A case report and review of literature

BACKGROUND: Leiomyosarcoma (LMS) of the thyroid gland is a rarely presented tumor that offers poor prognosis. To the best of the authors’ knowledge, there currently exist only 28 known cases described in the literature (limited to English). CASE SUMMARY: Herein a case is reported of a 60-year-old female patient who had an LMS of the thyroid, which was accompanied by periodic dysphonia and breathing disorder as well as the feeling of pressure in the chest and neck. At the time the disease was diagnosed, no metastases were detected. Prior to the diagnosis, the patient experienced a uterine adenocarcinoma that had been treated by surgical procedure and radiotherapy. For the LMS, a total thyroidectomy was performed, followed by radiotherapy. Since metastases were also discovered in the lungs, sternum, and femur, chemotherapy was administered as well. Immunohistochemically, the tumor cells in the thyroid indicated positively for alpha smooth muscle actin, calponin, and H-caldesmon, but were negative for CD34, p63, estrogen receptor, progesterone receptor, and Epstein-Barr virus. CONCLUSION: Although the etiology of the LMS is as of yet unknown, prior malignancy and radiation should be considered as risk factors.