2012 Volume 61 Issue 2 Pages 192-196
Glomus tumor is usually benign, but some rare cases show malignant features such as relapse and metastasis. We experienced one case with repeated relapse and metastasis for about 25 years.
The subject was a 64-year-old male whose left kidney lesion was assumed to start at age 38. Metastatic lesions of the left buttock and in both lungs were found simultaneously at 53 and treated surgically. At 64, the tumor on his left buttock recurred. Embolization was performed on feeding vessels before surgery, and radiation therapy (50 Gy/25 fr) of the residual tumor after surgery. It is uncertain if the lesion occurring at 38 was malignant, but the present recurring lesion was malignant according to Folpe's criteria.
Malignant glomus tumor is very rare, and standard diagnosis and treatment have yet to be established. Pathological findings, location, and size are thus important for deciding appropriate therapy. The tumor in this case is assumed to have gradually become malignant, and requires continuous careful observation over a long time.
