'Eruptive syringoma': a misnomer for a reactive eccrine gland ductal proliferation?

Syringomas have traditionally been categorized as benign neoplasms of the eccrine gland ductal epithelium. However, the variety of clinical presentations reported in the literature and some cases recently observed by the authors cast doubt upon the neoplastic nature of eruptive syringomas. Our goal is to challenge the traditional notion that eruptive syringomas are neoplastic lesions.

We observed two patients who presented with an eczematous process, which resolved leaving residual lesions. Biopsies of the late lesions showed features of eccrine syringoma. Yet a biopsy obtained from an incipient lesion in one of the cases showed a lymphocytic inflammatory reaction of the superficial portion of the eccrine duct resulting in tortuous hyperplastic changes.

Based on our observations, some of the so-called 'eruptive syringoma' may represent a hyperplastic response of the eccrine duct to an inflammatory reaction rather than a true adnexal neoplasm. We proposed the term 'syringomatous dermatitis' for such cases.