Aneurysmal bone cyst can present as subungual mass

(HealthDay)—In a case report published online April 23 in the Journal of Cutaneous Pathology, a subungual aneurysmal bone cyst is described in a 39-year-old male patient.

Cornelia Sigrid Lissi Müller, M.D., from Saarland University Medical School in Germany, and colleagues document the case of a 39-year-old male presenting for evaluation of a newly-developed, rapidly-growing, subungual mass of the first toe of the right foot.

The researchers identified a cavernous uplift on preoperative X-ray of the toe, with demineralization of the distal part of the toe and erosion of the cortical bone. Prominent swelling of the adjacent soft parts was also seen. There were no radiologic signs of malignancy. Extirpation of the entire lesion was planned after removal of the nail plate based on the clinical diagnosis of subungual glomus tumor. A sanguinary tumor presented during surgery, which passed over the subungual area into the underlying bone, with no clinical demarcations. Surgery was stopped and a large tumor replacing the distal phalangeal bone was revealed on computed tomography and magnetic resonance imaging. A coordinated image-guided amputation of the distal part of the distal phalanx was performed due to complete destruction of the bone and critical soft parts.

"We describe this rare entity to encourage clinicians to establish the diagnosis by biopsy of a tissue swelling of unclear origin and duration that does not resolve after a short time," the authors write.