# A Large Mass over the Foot due to the Coexistence of an Eccrine Poroma and a Poroid Hidradenoma: A Case Report

## TL;DR

A rare case of a foot tumor combining two benign skin growths is reported, with successful surgical treatment and no recurrence.

## Contribution

The coexistence of eccrine poroma and poroid hidradenoma in a single lesion is documented for the first time.

## Key findings

- The tumor was located on the foot and exhibited features of both eccrine poroma and poroid hidradenoma.
- Surgical excision successfully treated the lesion with no recurrence observed during follow-up.
- The case highlights the importance of histopathological analysis for accurate diagnosis of rare skin tumors.

## Abstract

Eccrine poroma and poroid hidradenoma are uncommon benign poroid neoplasms derived from eccrine sweat glands. There are four types of poroid neoplasms according to the position within the skin layer: hidroacanthoma simplex, eccrine poroma, dermal duct tumor, and poroid hidradenoma. Poroid neoplasms usually arise as slow-growing solitary lesions and can present different clinical presentations, such as a foot mass, an ulceration lesion, a solid cyst, a bleeding lesion or suspected melanoma. Extremities are the most common sites, especially hands and feet. However, the coexistence of these two tumors in a single lesion is extremely rare. Surgical excision represents the main treatment and can be curative, preventing malignant changes and recurrence. We describe a rare solitary tumor over the foot with clinical and histopathological features of an association of an eccrine poroma and a poroid hidradenoma that was surgically treated with no recurrence at the midterm follow-up.

Level of Evidence
 IV, Case Report.

O poroma écrino e o hidradenoma poroide são neoplasias poroides benignas raras, derivadas das glândulas sudoríparas écrinas. Existem quatro tipos de neoplasias poroides, conforme a posição na camada da pele, sendo denominadas hidroacantoma simples, poroma écrino, tumor do ducto dérmico e hidradenoma poroide. As neoplasias poroides geralmente surgem como uma lesão solitária, com crescimento lento, podendo apresentar diferentes apresentações clínicas, como massa sobre o pé, lesão ulcerada, cisto sólido, lesão hemorrágica ou suspeita de melanoma. As extremidades são os sítios mais comuns, especialmente as mãos e os pés. No entanto, a coexistência desses dois tumores em uma única lesão é extremamente rara. A excisão cirúrgica representa o principal tratamento, podendo ser curativa, prevenindo assim as alterações malignas e as recidivas. Descrevemos um raro tumor solitário no pé com características clínicas e histopatológicas de uma associação de poroma écrino e hidradenoma poroide tratado cirurgicamente sem recidiva no acompanhamento de médio prazo.

Nível de Evidência
 IV, Relato de Caso.