Angiokeratoma of the Scrotum Differential Diagnoses

Updated: Jun 07, 2022
  • Author: Yoon-Soo (Cindy) Bae, MD; Chief Editor: Dirk M Elston, MD  more...
  • Print

Diagnostic Considerations

Patients with history of genitourinary malignancy and subsequent surgical or radiation therapy may develop angiokeratomas of Fordyce. These lesions may be alarming as potential recurrence [13] or metastatic presentation of the cancer. Performing a biopsy and reassuring patients of the benign nature of these lesions is important.

The most ominous clinical differential diagnosis is malignant melanoma. Angiokeratomas are composed of superficial vessels immediately below the epidermis, and the lesions can appear deeply pigmented or black with intraepidermal hemorrhage or subepidermal thrombosis. From a clinical standpoint, this can simulate the clinical appearance of melanoma. In addition to melanoma, there are cases in which this condition has been mistaken for penile cancer [30] or keratoacanthoma. [35]  If the diagnosis is in doubt, the patient should be referred to a dermatologist to examine the lesion and biopsy, if necessary. In addition, dermoscopy can be useful to distinguish a vascular lesion from a melanocytic neoplasm or other malignancy.

Fordyce angiokeratomas also must be distinguished from angiokeratomas of Fabry disease. Patients with Fabry disease may report lancinating limb pain or a history of renal disease. Routine histology sometimes demonstrates vacuoles within endothelial cells in patients with Fabry disease. Electron microscopy may demonstrate lamellated inclusion bodies within endothelial cells. Fabry disease should be considered when angiokeratomas are present on the shaft, sacrum, or suprapubic areas in addition to the scrotum. Also see angiokeratoma corporis diffusum

Differential Diagnoses