BCOR Internal Tandem Duplication Associated Uterine Sarcoma: Expanding the Clinicopathologic Spectrum

Area of Science:

• Gynecologic Oncology
• Pathology
• Molecular Diagnostics

Background:

• High-grade endometrial stromal sarcoma diagnosis is evolving with molecular insights.
• BCOR internal tandem duplications (ITD) are recently identified genetic alterations in a subset of these tumors.

Observation:

• A case of HG-ESS with BCOR ITD in a young female patient presenting with menorrhagia.
• Histopathological findings revealed a spindle cell neoplasm with specific cytologic and mitotic features.
• Immunohistochemistry showed diffuse cyclin D1 positivity, focal CD10 positivity, and negativity for other markers.

Findings:

• BCOR ITD was confirmed via polymerase chain reaction and Sanger sequencing.
• The tumor exhibited characteristic features including young patient age, uniform nuclear morphology, and strong cyclin D1 expression.

Implications:

• Recognizing these clinical and molecular features can guide the diagnosis of BCOR ITD-positive uterine sarcoma.
• Accurate molecular diagnosis is crucial for appropriate patient prognostication and management of this rare sarcoma.