A case report of thyroid myofibroblastic sarcoma.

RATIONALE: High-grade myofibroblastic sarcoma (HGMS) is a rare mesenchymal tumor with a high recurrence and metastatic rate. Few cases of high-grade myofibroblastic sarcomas have been reported. Herein, we report the first case of HGMS originating from the thyroid.

DIAGNOSIS AND PATIENT CONCERNS: Based on the findings of thyroid, pathological examination, and immunohistochemical staining, grade III myofibroblastic sarcoma (MS) was diagnosed. Meanwhile, systemic imaging revealed multiple metastases in the scalp, lung, bone, liver, spleen, pancreas.

INTERVENTIONS AND OUTCOME: The patient had not received any treatment and expired 28 days after admission.

LESSONS: HGMS of thyroid shows high invasiveness and metastatic potential, often leading to rapid disease progression and poor survival outcomes. Early diagnosis and intervention guided by clinical evaluation, pathological findings, and imaging are essential to improve patient prognosis.