Am Fam Physician. 2008;77(10):1449-1450
Author disclosure: Nothing to disclose.
A 64-year-old man presented with a lesion on his right foot. Over the preceding three years, the lesion had slowly increased in size. The patient denied pruritus, pain, bleeding, or ulceration of the lesion.
On physical examination, a pink, fleshy, dome-shaped papule, 9 mm in diameter, was noted at the dorsal base of the right second toe (see accompanying figure). A shave biopsy was performed.
Question
Discussion
The correct answer is C: fibroepithelioma of Pinkus. Pathologic evaluation of the biopsy specimen revealed an intricate, net-like proliferation of thin, branching, anastomosing strands of basaloid cells embedded in a loose, dermal, fibrovascular stroma. This histologic pattern is consistent with fibroepithelioma of Pinkus. Fibroplasia of the dermal stroma and solar elastosis were also noted.
In 1953, Hermann Pinkus originally described the condition as a premalignant fibroepithelial skin tumor that may develop into basal cell carcinoma.1 The lesion usually appears as a flesh- to pink-colored, dome-shaped, sessile papule; however, there has been at least one report of a pigmented lesion.2
Regardless of the pathologic classification, the clinical behavior of fibroepithelioma of Pinkus differs from that of basal cell carcinoma. Classic basal cell carcinoma appears as an erythematous patch (superficial variant) or a pearly, translucent papule with adjacent vascular dilatation (nodular variant). In addition, basal cell carcinoma locally invades surrounding tissue, resulting in bleeding, local extension, and ulceration. In contrast, fibroepithelioma of Pinkus is papular without a pearly appearance and does not lead to telangiectasias. Fibroepithelioma of Pinkus has a much more indolent and less aggressive clinical course.5,6 Basal cell carcinoma typically occurs on sun-exposed areas of the head and neck, whereas fibroepithelioma of Pinkus typically occurs on the trunk.4
Treatment of fibroepithelioma of Pinkus is similar to that of other variants of basal cell carcinoma. Simple excision with 4-mm margins is usually adequate, although Mohs' surgery is an alternative.6 Curettage and electrodesiccation, cryosurgery, and radiation are less favorable treatment modalities.
Acquired digital fibrokeratomas are nodular, isolated, flesh-colored growths that typically occur on the hands and feet. The growths are pedunculated or sessile and have been associated with trauma of the affected area.7
Digital mucinous cysts are mucin collections that appear as soft, pink-white to translucent growths on the dorsal surface of a distal phalanx. They most commonly occur in middle-age and older adults.8
Intradermal nevi may lose pigmentation over time and can transition from brown hues to a light-pink color. Dome-shaped lesions are common, although verrucous, polypoid, or pedunculated lesions also may occur.8
Pyogenic granulomas are acquired vascular lesions of the skin and mucous membranes. The rapidly growing lesions are bright red, glistening, and dome shaped. They are more common in children and young adults and are triggered by trauma or hormonal factors.8
| Condition | Characteristics |
|---|---|
| Acquired digital fibrokeratoma | Isolated, flesh-colored, pedunculated or sessile nodule; collarette of scale surrounding the lesion |
| Digital mucinous cyst | Soft, pink-white to translucent, solitary, dome-shaped nodule |
| Fibroepithelioma of Pinkus | Pink- to flesh-colored, solitary, dome-shaped, sessile papule |
| Intradermal nevus | Brown- to pink-colored lesion; dome-shaped, pedunculated or sessile papule |
| Pyogenic granuloma | Bright red, glistening lesion; eruptive, rapid growth; friable; bleeding and ulceration are common; polypoid nodule or papule |