# Management of Glycogen-Rich Clear Cell Carcinoma of the Breast: A Case Report

## TL;DR

A 75-year-old woman with a rare breast cancer called glycogen-rich clear cell carcinoma is described, highlighting the diagnostic challenges and treatment approach.

## Contribution

This case emphasizes the importance of excisional biopsy and multidisciplinary discussions in managing rare breast cancers like GRCC.

## Key findings

- GRCC was diagnosed after initial discordant biopsy results and subsequent MRI-guided biopsy.
- Multidisciplinary discussion led to a treatment plan involving radiation, hormonal, and chemotherapy.
- The case underscores the diagnostic challenges and management complexities of rare breast tumors.

## Abstract

This case report presents an asymptomatic 75-year-old female with a screening mammogram revealing a left-sided breast lesion, ultimately diagnosed as glycogen-rich clear cell carcinoma (GRCC) following a comprehensive evaluation and histopathological confirmation. Initial ultrasound-guided biopsy suggested a papillary neoplasm, which was discordant, and was followed by a magnetic resonance imaging (MRI)-guided biopsy showing fibrocystic changes throughout and a complex sclerosing lesion with flat epithelial atypia. We proceeded with a lumpectomy without a sentinel lymph node biopsy. Final pathology revealed findings consistent with GRCC. A multidisciplinary discussion recommended forgoing axillary surgery and proceeding with radiation, hormonal therapy, and chemotherapy. This case highlights the challenges of diagnosing rare cancers, such as GRCC, and the importance of excisional biopsy in the diagnostic process. We also emphasize the importance of multidisciplinary tumor board discussions regarding rare lesions, such as GRCC, to help guide disease management and follow-up.