Metastatic Malignancies to the Ovaries: Often Hiding in Plain Sight

Area of Science:

• Gynecologic Pathology
• Oncology
• Diagnostic Pathology

Background:

• Metastatic neoplasms account for 5% to 30% of ovarian malignancies.
• Various primary sites, including colorectal, breast, and stomach, can metastasize to the ovary.

Purpose of the Study:

• To outline features distinguishing primary ovarian neoplasms from metastatic lesions.
• To discuss immunohistochemical markers for identifying the primary tumor site.

Main Methods:

• Literature review and analysis of author practice cases.
• Evaluation of clinical, radiologic, laboratory, gross, and histologic findings.
• Application of immunohistochemical stains (e.g., CK7, CK20, SATB2, PAX8, WT1).

Main Results:

• Clinical history, radiology (absence of ascites), and lab tests (CA 125, CEA) offer clues.
• Gross features like bilaterality and multinodular growth suggest metastasis.
• Histologic patterns (infiltrative, mucin, signet rings) and immunohistochemistry aid in site determination.

Conclusions:

• A combination of clinical, imaging, laboratory, gross, and microscopic features is essential for accurate diagnosis.
• Immunohistochemistry plays a vital role in pinpointing the primary tumor origin.
• Correctly differentiating primary from metastatic ovarian tumors is critical for patient prognosis and therapeutic management.