A 52-year-old postmenopausal woman presents with progressive abdominal distension and pelvic pain. Transvaginal ultrasound reveals a 6 cm complex cystic and solid ovarian mass with internal septations. Serum CA-125 is elevated at 185 U/mL. Which investigation is most appropriate to confirm the diagnosis and assess resectability before surgical intervention?

Explanation

## Investigation of Choice for Epithelial Ovarian Cancer Staging **Key Point:** CT abdomen/pelvis with IV contrast is the standard imaging modality for initial staging and assessment of resectability in suspected epithelial ovarian cancer. ### Why CT is the Gold Standard 1. **Comprehensive assessment** — evaluates the primary tumor, ascites, peritoneal involvement, omental caking, and distant metastases in a single study 2. **Resectability assessment** — determines feasibility of optimal cytoreduction by identifying: - Diaphragmatic involvement - Hepatic metastases - Peritoneal carcinomatosis extent - Bowel involvement 3. **Rapid and reproducible** — faster than MRI, widely available, and standardized for oncologic staging 4. **Cost-effective** — compared to MRI or PET, with superior sensitivity for detecting peritoneal disease ### Role of Other Investigations | Investigation | Role | Limitation | |---|---|---| | **Transvaginal ultrasound** | Initial characterization of adnexal mass | Limited assessment of peritoneal disease and distant spread | | **MRI pelvis** | Better soft tissue characterization, problem-solving | Not first-line; reserved for specific indications (e.g., distinguishing endometriosis) | | **Diagnostic laparoscopy** | Tissue diagnosis and staging | Invasive; not routine; may miss upper abdominal disease | | **PET-CT** | Metastatic disease detection | Not standard for initial staging; reserved for recurrent disease | **Clinical Pearl:** The combination of elevated CA-125, complex ovarian mass on ultrasound, and postmenopausal status is highly suspicious for epithelial ovarian cancer. CT staging is mandatory before surgical planning to determine if optimal cytoreduction is achievable. **High-Yield:** CT abdomen/pelvis is part of the standard preoperative workup (along with CA-125, CBC, renal/hepatic function) and should be completed BEFORE surgery to guide the surgical team on extent of disease and feasibility of complete resection. [cite:Robbins 10e Ch 24]