Multiple morphologically distinct cutaneous granular cell tumors occurring in a single patient.

Granular cell tumors (GCTs) typically are benign solitary tumors derived from Schwann cells. The tongue and skin are the most common sites of involvement; however, lesions also can develop in viscera such as the gastrointestinal tract. Multiple cutaneous GCTs in a single patient have been reported, with the lesions being described as subcutaneous papules, nodules, or verrucous nodules. We report the case of a patient who presented with several simultaneously occurring cutaneous GCTs with morphologically distinct clinical appearances ranging from subcutaneous nodules with no overlying epidermal alteration to exophytic moist nodules with eroded surfaces. Histopathology of several lesions was diagnostic of GCTs. This case illustrates the highly varied clinical presentation and morphology of cutaneous GCTs, even those occurring in a single patient. In addition to mimicking other benign neoplasms, GCTs may mimic other disease processes, including malignant lesions, infections, and inflammatory disorders. Skin biopsy generally is required for definitive diagnosis.