# Low-Powered View, High-Powered Mind: A Case Report of Morpheaform Basal Cell Carcinoma Mistaken for Metastatic Breast Carcinoma

## TL;DR

A rare skin cancer was misdiagnosed as a more severe breast cancer, highlighting the need for accurate diagnosis to avoid harmful treatments.

## Contribution

This case report highlights diagnostic challenges between morpheaform BCC and metastatic breast carcinoma using immunohistochemistry.

## Key findings

- A 77-year-old patient with MBCC was initially misdiagnosed with metastatic breast carcinoma.
- Overlap in immunohistochemistry stains can lead to diagnostic confusion between these two malignancies.
- Combining clinical expertise with laboratory medicine is crucial for accurate diagnosis and treatment.

## Abstract

Basal cell carcinoma (BCC) is one of the most common skin malignancies worldwide. Morpheaform basal cell carcinoma (MBCC) is a rare aggressive subtype of BCC that presents with unique histologic features. Both are treated surgically and have an excellent survival rate. Metastatic breast carcinoma, on the other hand, has a poor survival rate along with a more burdensome therapeutic route including chemotherapy. Due to an overlap in common immunohistochemistry stains, there is a possibility of confusing the diagnosis of BCC with metastatic breast carcinoma resulting in potential patient harm. Therefore, a timely and accurate diagnosis distinguishing these malignancies is essential. We report a near-miss event in which a 77-year-old female with MBCC was mistakenly diagnosed with metastatic breast carcinoma. We discuss the details of these stains, characteristic features of MBCC, and treatment options and emphasize the importance of combining laboratory medicine with clinical expertise to improve patient outcomes.