[Atypical glomus tumor. Report of a case].

The solitary glomus tumor is considered by many authors a benign cutaneous neoplasm which gives rise to severe paroxysmal pains and it is frequently localized in the subungual region. Malignant glomus tumors have not been found in the skin but if in the stomach and duodenum. This study reports a case of 62 year old woman with a painful red nodule of 0.80 cm. in diameter, situated on the dorsal right arm. The duration of illness was unknown. Histopathologic studies showed a dermal tumor characterized by multilobulated masses composed of glomus cells and a high portion of anaplastic, pleomorphic cells. Cytochemical stain showed a myxoid matrix composed of nonsulphated acid mucopolysaccharides in which the tumor mass lies.