A 52-year-old postmenopausal woman from Delhi presents with progressive abdominal distension and mild discomfort for 3 months. She reports early satiety and occasional nausea. On examination, she has a palpable suprapubic mass and mild ascites. CA-125 is markedly elevated at 680 U/mL. CT abdomen shows a 12 cm left ovarian mass with peritoneal nodules and ascites. Diagnostic laparoscopy reveals tumor deposits on the omentum and peritoneal surfaces. Histology confirms high-grade serous adenocarcinoma. After staging laparotomy, she is found to have tumor confined to the left ovary with omental involvement but no distant metastases. What is her FIGO stage?

Explanation

## FIGO Staging of Ovarian Cancer — Stage IIIC ### Clinical Interpretation This patient has: - Primary tumor confined to the left ovary (Stage I criterion) - **Omental involvement** (metastatic disease beyond the ovary) - **Peritoneal nodules** (peritoneal metastases) - No distant metastases (excludes Stage IV) The presence of **peritoneal metastases and/or omental involvement** automatically elevates the stage from Stage I to **Stage III**. ### FIGO 2014 Staging Hierarchy | Stage | Criteria | |-------|----------| | **IA** | Tumor limited to one ovary; intact capsule; no surface involvement; no malignant ascites | | **IB** | Tumor limited to both ovaries; intact capsules; no surface involvement; no malignant ascites | | **IC** | Stage IA or IB with: (1) surface involvement, OR (2) ruptured capsule, OR (3) malignant ascites/peritoneal washings | | **IIIA** | Microscopic peritoneal metastases beyond pelvis | | **IIIB** | Macroscopic peritoneal metastases ≤2 cm beyond pelvis | | **IIIC** | Macroscopic peritoneal metastases >2 cm beyond pelvis OR positive retroperitoneal lymph nodes | | **IV** | Distant metastases (pleural effusion with positive cytology, liver/splenic parenchymal involvement, brain) | ### Key Distinction: IIIB vs IIIC **Key Point:** The size of peritoneal metastases determines whether a patient is IIIB or IIIC. - **IIIB:** Macroscopic peritoneal nodules ≤2 cm - **IIIC:** Macroscopic peritoneal nodules **>2 cm** OR retroperitoneal lymph node involvement This patient's omental involvement (a macroscopic deposit typically >2 cm) and peritoneal nodules place her in **Stage IIIC**. ### Prognostic Significance **High-Yield:** Stage IIIC ovarian cancer has a 5-year survival of approximately 30–40% with optimal cytoreduction and platinum-based chemotherapy, compared to >90% for Stage IA disease. **Clinical Pearl:** Omental involvement is one of the most common sites of peritoneal metastasis in ovarian cancer and is a hallmark of Stage III disease. The presence of ascites with elevated CA-125 further supports advanced-stage disease. ### Management Implications 1. **Optimal cytoreduction** is the primary surgical goal (residual tumor <1 cm) 2. **Neoadjuvant chemotherapy** (platinum + paclitaxel) followed by interval debulking may be considered if not optimally cytoreducible upfront 3. **Adjuvant platinum-based chemotherapy** (6 cycles of carboplatin + paclitaxel) is standard 4. **PARP inhibitor maintenance** (olaparib, niraparib) is now standard of care for Stage III/IV ovarian cancer post-chemotherapy [cite:FIGO Staging 2014, Gynecologic Oncology]