Cancer-related microangiopathic hemolytic anemia (CR-MAHA) in a metastatic breast cancer patient with a germ-line ATM single nucleotide variant and an ESR1 fusion variant: insights from a case report on early diagnosis and improved outcomes.

Publication Title

Front Oncol

Authors

• Fengting Yan, Swedish Cancer Institute, Seattle, WA, United States.
• Aimee Wu
• Yufei Wang
• Tanya Wahl, Swedish Cancer Institute, Seattle, WA, United States.Follow
• Zirui Wang
• Cesar Gutierrez, Swedish Cancer Institute, Seattle, WA, United States.Follow
• Josiah T Wagner, Providence Institute for Clinical Innovation, Portland, OR, United States.Follow
• Alexa K Dowdell, Providence Institute for Clinical Innovation, Portland, OR, United States.; Earle A Chiles Research Institute, Providence Cancer Institute, Portland, OR, United States.Follow
• Alexandra Q Bartlett, Providence Institute for Clinical Innovation, Portland, OR, United States.; Earle A Chiles Research Institute, Providence Cancer Institute, Portland, OR, United States.Follow
• Christopher Carney
• Daniel Landis, Swedish Cancer Institute, Seattle, WA, United States.Follow
• Brian D. Piening, Providence Institute for Clinical Innovation, Portland, OR, United States.;Earle A Chiles Research Institute, Providence Cancer Institute, Portland, OR, United States.Follow
• Henry G Kaplan, Swedish Cancer Institute, Seattle, WA, United States.Follow

Document Type

Article

Publication Date

1-1-2026

Keywords

ATM; ESR1; cancer-related microangiopathic hemolytic anemia; case report; metastatic breast cancer.; washington; swedish; oregon; chiles

Abstract

Cancer-related microangiopathic hemolytic anemia (CR-MAHA) is a rare and life-threatening paraneoplastic syndrome that carries a poor prognosis if not recognized early. While existing reports primarily focus on clinical outcomes, the underlying molecular changes remain poorly understood. We present a case in which the patient initially presented with back pain and fatigue. Further diagnostic workup confirmed the diagnosis of CR-MAHA, and she was promptly initiated on treatment, resulting in an excellent clinical anti-tumor response and resolution of the hemolytic anemia. Genomic testing revealed a germ-line ATM single nucleotide variant and an ESR1 fusion variant. This case raises important questions regarding potential genomic alterations that may predispose individuals to CR-MAHA and underscores the necessity for further investigation of tumor samples from these patients using both DNA and RNA sequencing.

Area of Special Interest

Cancer

Specialty/Research Institute

Oncology

DOI

10.3389/fonc.2026.1755142