Acquired Digital Fibrokeratoma

Background

In 1968, Bart et al described 10 cases of an uncommon acquired growth that was located on the fingers. Although it clinically resembled a cutaneous horn or rudimentary supernumerary digit, it had distinct histopathological findings. The authors named this growth acquired digital fibrokeratoma (ADFK). Subsequently, Pinkus reported 28 more cases; however, because the lesions Pinkus described also occurred on the proximal hand, toes, soles, and one in the prepatellar region, he suggested the entity might be more appropriately called acquired acral fibrokeratoma.

Pathophysiology

Despite the fact that most patients deny a history of precedent trauma, the major hypothesis is that subclinical injury contributes to the development of these lesions.

Frequency

United States

Currently, no means of tracking nonmelanoma skin cancer, much less various benign dermatological conditions, is in place in the United States; therefore, the actual incidence of acquired acral fibrokeratoma is unknown. Most cases reported in the literature involve individual case reports presented because of the lesions' unusual size, location, histological features, or association with other conditions. Only a few reports describe a series of patients, with 129 patients being the most reported from any one institution. Therefore, whether this condition is rare or rarely reported remains unknown.

Mortality/Morbidity

ADFKs are benign stationary lesions that are more cosmetically bothersome than they are problematic. However, patients who have been reported to have giant acral digital fibromas on the dorsum or plantar surface of the foot may report some discomfort.

Race

ADFKs have been reported in persons of all races.

Sex

ADFKs seem to have a slight male predominance; however, too few cases have been described to adequately assess the significance of any sexual predilection.

Age

The patients reported with ADFKs range in age from 12-70 years, with most cases occurring in middle-aged adults. Clinically similar lesions that occur in young children are more likely to represent rudimentary supernumerary digits.

Treatment

Surgical Care

Simple excision is curative, recurrence is rare.