# Recurrent melanoma presenting as a rash: a case report

## TL;DR

A woman with melanoma developed a rash after T-VEC therapy, which was later confirmed as a rare recurrence of the cancer.

## Contribution

This case report highlights an unusual presentation of melanoma recurrence as a rash rather than typical pigmented lesions.

## Key findings

- A spreading erythematous rash on the left leg was found to be recurrent melanoma.
- Skin biopsy confirmed recurrence with SOX10 and Melan-A positivity.
- Imaging suggested multifocal disease recurrence in the left popliteal fossa.

## Abstract

Melanoma is the most aggressive form of common skin cancer and recurrence, while rare, typically presents as pigmented papules or nodules near the primary site. Here, we describe a case of a woman with stage IIIC melanoma undergoing intralesional talimogene laherparepvec (T-VEC) therapy who developed a spreading erythematous rash on her left leg, accompanied by fatigue and leg swelling. Skin biopsy revealed recurrent melanoma, with SOX10 and Melan-A positivity, and imaging showed features concerning for multifocal disease recurrence in the left popliteal fossa. This case highlights an unusual presentation of melanoma recurrence and underscores the importance of biopsy in ­evaluating new skin findings in patients with a history of melanoma.

Melanoma often presents as a brown to black pigmented lesion with changes in size, shape or colour. Our study presents a unique case of recurrent melanoma presenting as a rash following a T-VEC injection.