# A rare case of extra-digital glomus tumor of the thigh

## TL;DR

This paper reports a rare case of a glomus tumor in the thigh, highlighting the importance of considering this diagnosis for painful subcutaneous lesions to avoid misdiagnosis.

## Contribution

The paper presents a rare case of an extra-digital glomus tumor in the thigh and emphasizes its diagnostic challenges.

## Key findings

- Glomus tumors in the thigh are exceptionally rare and often misdiagnosed due to atypical symptoms.
- Surgical excision is the effective treatment for glomus tumors, providing immediate pain relief.
- Early clinical suspicion and imaging can prevent delayed diagnosis and treatment.

## Abstract

Glomus tumors are rare benign tumors arising from glomus bodies that are responsible for thermoregulatory control. Their typical location is the subungual area of the digits, and extra-digital glomus tumors are very rare, leading to misdiagnosis and delayed treatment due to the absence of typical symptoms.

Here, we report the case of a 49 years old male patient with a long history of localized right thigh pain who was found to have an extra-digital glomus tumor of the thigh after surgical excision.

A comprehensive physical examination, detailed medical history, in depth imaging and early surgical excision upon clinical suspicion may prevent delayed or incorrect diagnosis. The treatment of glomus tumor is surgical excision providing immediate relief from pain, however if the lesion is not palpable, it can be easily missed or confusing with other diagnoses such as schwannoma, neuroma or arteriovenous malformation.

Glomus tumors of the thigh represent an exceptional location for extra digital glomus tumors. The aim of this report was to make the surgical community more aware of this entity to prevent delayed treatment and misdiagnosis. Glomus tumor should be kept in mind in the differential diagnosis of all painful subcutaneous lesions.

•Glomus tumors are benign neoplasms containing cells from the glomus apparatus which is responsible for thermoregulatory control. It is a rare tumors accounting for only 1-2% of all soft tissue tumors that usually presents as a painful subcutaneous nodule formation located on the subungual area of the digits.•Extra-digital glomus tumors are a very rare presentation and the location in the thigh is exceptional with only a few cases reported in the literature.•The treatment of glomus tumor is surgical excision providing immediate relief from pain, however if the lesion is not palpable, it can be easily missed or confusing with other diagnoses such as schwannoma, neuroma or arteriovenous malformation.•Glomus tumor should be kept in mind in the differential diagnosis of all painful subcutaneous lesions.

Glomus tumors are benign neoplasms containing cells from the glomus apparatus which is responsible for thermoregulatory control. It is a rare tumors accounting for only 1-2% of all soft tissue tumors that usually presents as a painful subcutaneous nodule formation located on the subungual area of the digits.

Extra-digital glomus tumors are a very rare presentation and the location in the thigh is exceptional with only a few cases reported in the literature.

The treatment of glomus tumor is surgical excision providing immediate relief from pain, however if the lesion is not palpable, it can be easily missed or confusing with other diagnoses such as schwannoma, neuroma or arteriovenous malformation.

Glomus tumor should be kept in mind in the differential diagnosis of all painful subcutaneous lesions.