1. What essential questions does one still need to ask to help make the diagnosis?
2. What is the tentative diagnosis?
3. Can you list at least three differential diagnoses?
4. What features of this condition differentiate it from other conditions in your differential?
5. What is the suitable treatment of this condition?
When A Patient Has An Unusual Growth On A Toe
Recognizing The Signs Of An Acquired Periungual Fibrokeratoma
The diagnosis is acquired periungual fibrokeratoma. This condition presents as solitary, elongated or dome-shaped papules with tall finger-like protrusions and a hyperkeratotic surface. The base may have a characteristic collarette of raised skin.2 Most lesions are small and do not exceed 1.5 cm in length or diameter.
In this case, the patient’s lesion was 1.8 cm in length. In regard to acquired periungual fibrokeratoma, the most common sites of occurrence are fingers and toes. However, lesions on the palms and soles can occur. Often, the lesion emerges from beneath the proximal nail fold with a narrow base and hyperkeratotic tip. The lesions may be multiple and grow on the nail plate, causing longitudinal grooves. Occasionally, acquired digital fibrokeratoma may be pedunculated and the surface may appear warty.3,4
The condition occurs solely in adults and is believed to result from trauma, whether it is due to an injury or due to shoe gear. These lesions are more of a cosmetic issue than a painful growth. Clinically similar lesions in children are more likely to represent rudimentary supernumerary digits.5 The condition is benign and surgical excision is curative. When it comes to periungual lesions arising below proximal nail folds, physicians should excise them with due care so as to not damage the matrix, which may result in permanent nail dystrophy.6