Background: Metastatic malignant melanomas to the uterus are extremely rare; to our knowledge, no more than 13 cases
have been reported to date.
Case Report: A 44-years-old multigravida woman presented with a black and irregular surface mass at medial aspect of left
thigh. There was also an enlarged left groin node. Wide excision with lymph node dissection revealed malignant melanoma. Further examination found a huge pelvic mass with left deep vein thrombosis consequent by pressure effect. Chest and complete abdominal computed tomography revealed an enlarged, fibroid uterus with pressure effect at left common iliac vein. A total abdominal hysterectomy and bilateral adnexectomy were performed. Intra-operative finding was scattered hyperpigment spots at surface of the uterus and its tumor. Histopathological report showed metastatic malignant melanoma involving myometrium and uterine serosa. Diagnosis of stage IV malignant melanoma (uterine metastasis) was achieved. The patient was counseled about her diagnosis, stage, prognosis and further treatment.
Conclusion: Uterine metastatic malignant melanoma was a rare condition. This report represents the first case of a cutaneous malignant melanoma involving a uterine leiomyoma in Thailand.

Keywords: Malignant Melanoma, Uterine Metastasis