Eccrine Poroma: Pathogenesis, New Diagnostic Tools and Association with Porocarcinoma—A Review

Abstract

Eccrine poroma (EP) is a relatively rare benign adnexal neoplasm that usually affects elderly patients. Its pathogenesis is still under investigation, but recent gene studies have revealed gene fusions as key incidences resulting in oncogenetic pathways. It often presents as a solitary, firm papule, mostly asymptomatic, located on the soles or palms. Due to its clinical and dermoscopic variability, it is characterized as the great imitator. We performed a literature review, aiming to summarize current data on the pathogenetic mechanisms, new dermoscopic features, and novel diagnostic tools that may aid in early diagnosis and proper management of this rare adnexal tumor. Furthermore, we reviewed the possible pathogenetic associations between EP and its malignant counterpart, namely eccrine porocarcinoma. This systematic approach may aid in understanding the pathogenetic mechanisms and how to use novel histopathologic markers and imaging methods to overcome the diagnostic dilemma of this rare tumor.

Navigating Head and Neck Porocarcinoma: Systematic Review with Special Emphasis on Surgical Safety Margins

“…Histopathological diagnosis of the suspected EPC lesion from a biopsy sample is further complicated due to a display of squamous differentiation, which could lead to misinterpretation, particularly in differentiating between EPC, basal, or squamous cell carcinomas. Due to this reason, it is believed that the prevalence of EPC may be underestimated [41].…”

“…This is because EPC cells could also display squamous differentiation, a factor that may introduce further confusion and potentially lead to misinterpretation, particularly in differentiating between EPC, basal, or squamous cell carcinomas. Due to this reason, it is believed that the prevalence of EPC may be underestimated [41].…”

“…In general, WLE is understood to involve the margin ranging from 1 to 2 centimetres (10 to 20 mm) or more around the tumour. Considering that the average size of EPC lesions in the H&N region is 30.1 mm [41], there is a notable risk that surgical excision with margins of 10 mm and more may lead to severe deformities or necessitate extensive reconstructions. Therefore, it is of outmost importance to note the significance of minimal surgical margins for the tumours located in the H&N areas.…”

Eyelid Eccrine Poroma: A Case Report and Literature Review

“…Ultraviolet radiation does not seem to be a key pathognomonic factor in poroma development, nor a pathogenic factor, evolving primarily in the deep dermis which is less affected by ultraviolet radiation [ 15 ]. On the other hand, several correlations have been found between long-term radiation exposure and the development of poroma [ 16 ]. We describe the case of a 23-year-old male (the youngest described at the time of surgery), with a lesion on the upper eyelid of the right eye and aspect of molluscum contagiosum, and we analyze all cases of eyelid poromas published in the literature.…”

Pigmented Poroma of the Lower Eyelid: A Case Report and Literature Review

“…Ultraviolet radiation does not seem to be a key pathogenic factor in poroma development. Merkel cell polyomavirus (MCPyV) infection, existing malignancies, and organ transplantation history are important risk factors [ 9 , 13 ].…”