# Cutaneous Squamous Cell Carcinoma as a Metastasis From Invasive Breast Cancer: A Case Report

## TL;DR

A 73-year-old woman was diagnosed with skin cancer that had spread from breast cancer, and it responded well to chemotherapy.

## Contribution

This case highlights the importance of accurate diagnosis of cutaneous metastasis from breast cancer.

## Key findings

- The patient's skin lesion was diagnosed as a metastasis from breast cancer, not a primary skin cancer.
- Timely diagnosis and chemotherapy led to a positive response in the patient's condition.
- Cutaneous metastasis from breast cancer can have a good prognosis with early treatment.

## Abstract

Cutaneous squamous cell carcinoma (cSCC) is a non-melanoma (keratinocyte) skin cancer. cSCC can occur as primary cSCC, second primary cancer (SPC), or metastasis. Histopathology and genetic or molecular studies are used to differentiate SPC from metastasis. Cutaneous metastasis (CM) is often misdiagnosed as a benign skin lesion. However, with early diagnosis and timely treatment, CM from breast cancer carries a good prognosis. Although surgery is the first-line treatment for cSCC, metastatic lesions respond well to chemotherapy and immunotherapy. Here, we present the case of a 73-year-old woman who presented to a dermatologist with a localized skin lesion. After detailed radiological and histopathological investigations, she was diagnosed with cSCC metastasis from breast cancer. With timely diagnosis, her CM responded well to chemotherapy.