Eccrine spiradenoma

Introduction

Eccrine spiradenoma an uncommon condition, appears mainly in young adults. It is one among the painful tumours of the skin and has characteristic histopathological findings.

Case Report

A 25-year-old woman presented with history of small painful hyperpigmented plaques over right elbow for past 10 years. It started as a small papule which slowly expanded. The surgical excision of the lesion was attempted six years ago with recurrence and presently has developed satellite lesions all around the site of excision. Examination revealed 8 x 5 cm sized surgical scar over the right elbow region along with five hyperpigmented and indurated annular plaques of varying sizes with central atrophy and peripheral rim of hyperpigmented papules [Figure - 1]. One small hyperpigmented papule was present over right forearm. All of these lesions were tender on firm pressure. Routine haematological and biochemical investigations were normal. Mantoux test was negative. Biopsy of the lesion in H & E section showed a non encapsulated deeply basophilic tumour mass in the dermis. In higher magnification, the epithelial cells in the tumour masses were found to be of 2 types the first type being small with dark nuclei at the periphery and the second type with large and pale staining nuclei located more towards the centre. The latter are seen to have been arranged around a small ductal lumina [Figure - 2], the features which prompted the diagnosis of eccrine spiradenoma. Enzyme studies could not be carried our on account of lack of facilities.

Discussion

The clinical appearance of the plaque with central atrophy and peripheral extension led to the diagnosis of various conditions like lupus vulgaris, atypical mycobacterial infection and annular sarcoidosis. But the presence of pain excluded the above possibilities and histopathology confirmed the diagnosis of tumour in the direction of both dermal duct and the secretary segment of the eccrine sweat gland, although the clinical appearance of the tumour was atypical showing annular distribution of small papules with central atrophy.

Eccrine spiradenoma is usually solitary benign tumour or rarely may be numerous small nodules and occasionally distributed in zosteriform pattern and appears as firm rounded, often tender bluish dermal nodule-aptly called as blue balls in the dermis.[1] The painful tumours of skin are limited and they are often remembered with acronym BLEND AN EGG which includes blue rubber bleb naevus, leiomyoma, eccrine spiradenoma, neuroma, dermatofibroma, angiolipoma, neurilemmoma, endometrioma, glomangiorna and granular cell tumour.[1] Eccrine spiradenoma is usually a benign tumour. But malignant transformation has been reported.[2] Though enzyme histochemical studies show enzymes of eccrine origin, sometimes it is not as strong as in syringoma or eccrine poroma.[3] Treatment is surgical excision. Recurrences have been reported as also was observed in our case.