Clinical and dermoscopic features of eccrine poroma

Bruno Simão dos Santos

 Dermatologic clinic, Rua Miguel de Frias, 40, Niterói - Rio de Janeiro, Brazil

Correspondence Address:
Bruno Simão dos Santos
Dermatologic clinic, Rua Miguel de Frias, 40, Niterói - Rio de Janeiro
Brazil

Sir,

A healthy 44-year-old male patient presented with a 3-year history of a slow growing lesion on the sole [Figure - 1]. Occasional bleeding and mild local pain under pressure were the only symptoms. Dermoscopy showed a pink homogeneous area and an ivory halo around the entire lesion. Multiple round-to-oval reddish structures surrounded by a white halo and dotted vessels were also seen. An incisional biopsy confirmed the clinical diagnosis of eccrine poroma (EP). The lesion was completely excised.

Figure 1: (a and b) Reddish papule with a scaly surface and a clear-cut keratotic border, located on the sole. (c) Polarized light dermoscopy with immersion fluid showing a pink homogeneous area and an ivory halo around the entire lesion. Multiple round-to-oval reddish structures surrounded by a white halo and dotted vessels may also be seen (original magnification, ×10)

Sweat gland tumors represent approximately 1% of primary skin lesions. Eccrine poroma is a benign sweat gland neoplasm that accounts for roughly 10% of sweat gland tumors. ^[1] Clinically, the tumour appears as a single slow-growing, asymptomatic, soft, well-circumscribed papule, plaque, or nodule, pink-to-red in color, with a surface ranging from smooth to verrucous, with occasional ulceration and/or scaling. ^[1],[2] Eccrine poroma commonly develops at the distal extremities, such as the soles, palms, and fingers. However, multiple lesions, pigmented variants, and other anatomical sites of localization, including the head and neck, may also occur. ^[2]

Dermoscopy of eccrine poroma is characterized by a vascular pattern, which may be polymorphous. Glomerular, hairpin vessels and linear irregular vessels, surrounded by a white to pink halo, may be observed. Reddish-white globule-like structures are occasionally seen, mimicking the red lacunae typical of vascular lesions, such as hemangioma or pyogenic granuloma. Milky-red areas, commonly found in melanoma, may also be present. ^[2] Pigmented globule-like structures, comedo-like openings, as well as blue-gray ovoid nests, arborizing vessels, and maple leaf-like structures similar to those of pigmented basal cell carcinomas are also described in pigmented variants of eccrine poroma. ^[3],[4] The dermoscopic findings described in previous reports of eccrine poroma have been summarized by Lallas et al. ^[5]

Eccrine poroma may exhibit polymorphic features that can make diagnosis difficult. The clinical and dermoscopic differential diagnoses include, among others, pyogenic granuloma, hemangioma, seborrheic keratosis, melanocytic nevus, amelanotic melanoma, and basal cell carcinoma. ^[6]

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