Uterine PEComa With Lymphangioleiomyomatosis (LAM)-Like Features: A Case Report

Area of Science:

• Gynecologic Pathology
• Oncology
• Medical Genetics

Background:

• Perivascular epithelioid cell tumors (PEComas) are rare uterine mesenchymal neoplasms with uncertain malignant potential.
• PEComas exhibit myogenic and melanocytic differentiation, often presenting diagnostic challenges due to overlapping features with other uterine tumors.
• Accurate differentiation is crucial for appropriate clinical management and prognosis.

Purpose of the Study:

• To report a case of uterine PEComa with lymphangioleiomyomatosis (LAM)-like features.
• To emphasize the diagnostic complexities and the importance of a multi-modal diagnostic approach.
• To highlight the role of immunohistochemistry and molecular testing in diagnosing rare uterine neoplasms.

Main Methods:

• Case presentation of a 58-year-old woman with abnormal uterine bleeding.
• Review of histopathological findings, including morphology and cytologic atypia.
• Application of immunohistochemical stains (HMB45, desmin, Cathepsin K) and genetic testing (TSC1 variant).

Main Results:

• Initial diagnosis was challenging, with initial considerations including leiomyoma and low-grade endometrial stromal sarcoma.
• Immunohistochemistry confirmed PEComa markers (HMB45, desmin, Cathepsin K).
• Identification of a TSC1 variant confirmed the diagnosis of uterine PEComa with LAM-like features.

Conclusions:

• Uterine PEComas require a comprehensive diagnostic strategy combining morphology, immunohistochemistry, and molecular analysis.
• Integrated assessment is vital for distinguishing PEComas from other uterine mesenchymal neoplasms.
• Early and accurate diagnosis facilitates appropriate patient management and monitoring.