[A malignant mixed mesodermal tumor of the ovary]

Area of Science:

• Gynecologic Oncology
• Pathology
• Surgical Oncology

Background:

• Malignant mixed mesodermal tumors (MMMTs) are rare and aggressive neoplasms.
• Primary ovarian MMMTs are exceptionally uncommon, particularly in postmenopausal women.

Observation:

• A 75-year-old woman presented with abdominal fullness and pain.
• Laparotomy revealed a large right ovarian tumor, ascites, omental masses, and peritoneal carcinomatosis.
• Microscopic examination showed a complex tumor with adenocarcinoma, adenosquamous carcinoma, and serous cystadenocarcinoma components.

Findings:

• The tumor demonstrated heterologous stromal differentiation, including immature striated muscle (rhabdomyoblasts), bone, cartilage, and undifferentiated spindle cells.
• Immunohistochemistry confirmed epithelial elements (cytokeratin, EMA, CEA) and mesenchymal components (vimentin, desmin, actin, myosin, myoglobin, S-100 protein).
• The diverse cellular components and aggressive nature were highlighted by specific immunohistochemical markers.

Implications:

• This case underscores the importance of comprehensive histopathological and immunohistochemical evaluation for diagnosing rare ovarian tumors.
• Understanding the diverse differentiation pathways in MMMTs is crucial for accurate diagnosis and potentially guiding treatment strategies.
• The aggressive behavior observed highlights the need for early detection and effective management of such rare gynecologic malignancies.