Inflammatory Myofibroblastic Tumor of the Breast Mimicking Complex Fibrocystic Changes, With a Novel CSTF3::ALK Fusion.
Michelle Garlin Politis, Mine Yilmaz, Diane Chen et al.
✦ AI-curated · Sources linked
Case in brief
A 38-year-old woman presented with a 7-mm breast lesion classified as BI-RADS 3, initially suspected to be fibrocystic changes. Follow-up ultrasound revealed growth to 10 mm, leading to a core needle biopsy. Histological examination showed a spindle cell lesion with inflammatory infiltrates, and immunohistochemistry was positive for ALK. FISH confirmed an ALK rearrangement, identifying a novel CSTF3::ALK fusion.
What made this case unusual
The case highlights a novel CSTF3::ALK fusion identified through targeted RNA sequencing, contributing to the understanding of genetic alterations in inflammatory myofibroblastic tumors.
Diagnostic / clinical pearl
Clinicians should consider inflammatory myofibroblastic tumor in the differential diagnosis of breast lesions, especially when imaging findings are nonspecific and there is growth over time.
Why it matters
This case emphasizes the importance of molecular testing in confirming diagnoses of atypical breast lesions, which can significantly impact management strategies.