A 52-year-old postmenopausal woman from Delhi presents with abdominal distension and pelvic pain for 3 months. Imaging reveals a 10 cm complex ovarian mass with ascites. CA-125 is 850 U/mL. Staging laparotomy with total abdominal hysterectomy, bilateral salpingo-oophorectomy, omentectomy, and peritoneal biopsies is performed. Histopathology confirms high-grade serous ovarian adenocarcinoma with stage IIIC disease (omental involvement). What is the most appropriate next step in management?

Explanation

## Management of Stage IIIC High-Grade Serous Ovarian Cancer **Key Point:** Stage IIIC ovarian cancer with optimal cytoreduction (residual disease <1 cm or complete gross resection) mandates adjuvant platinum-based chemotherapy as the standard of care. ### Rationale for Correct Answer This patient has: - **Stage IIIC disease** (omental involvement beyond the ovary) - **High-grade serous histology** (aggressive, chemosensitive) - **Optimal surgical cytoreduction** (complete gross resection achieved) The standard adjuvant regimen is **carboplatin (AUC 5–6) + paclitaxel (175 mg/m²) every 3 weeks for 6 cycles** [cite:FIGO Guidelines 2019]. Bevacizumab (anti-VEGF monoclonal antibody) is added as maintenance therapy in stage III–IV disease, particularly when residual disease >1 cm or suboptimal cytoreduction, based on GOG-218 and ICON7 trials. Even with optimal cytoreduction, bevacizumab maintenance improves progression-free survival (PFS) in stage III–IV disease. **High-Yield:** Platinum-taxane combination is the backbone of first-line chemotherapy for all epithelial ovarian cancers (EOC) stages IB–IV. Bevacizumab is now standard maintenance in stage III–IV after optimal cytoreduction. ### Why This Is the Next Step 1. **Observation alone** is inadequate—stage IIIC disease has high recurrence risk (>80% without chemotherapy). 2. **Optimal cytoreduction achieved**—no indication for secondary debulking. 3. **Chemotherapy is the proven standard**—improves overall survival (OS) and PFS. 4. **Bevacizumab maintenance** extends PFS by ~4 months in stage III disease (GOG-218). **Clinical Pearl:** In ovarian cancer, the goal of primary surgery is **complete gross resection (CGR)** or residual disease <1 cm. When achieved, adjuvant chemotherapy is the next critical step; no role for immediate re-operation. ### Treatment Algorithm for Stage III EOC (Post-Optimal Cytoreduction) ```mermaid flowchart TD A[Stage III EOC, Optimal Cytoreduction]:::outcome --> B{Residual disease?}:::decision B -->|None or <1 cm| C[Carboplatin + Paclitaxel x6 cycles]:::action C --> D[Bevacizumab maintenance]:::action B -->|>1 cm| E[Neoadjuvant chemotherapy + interval debulking]:::action D --> F[Surveillance: CA-125, imaging, clinical exam]:::action ``` **Mnemonic:** **CART-B** = **C**arboplatin + **A**djuvant **R**egimen **T**axane + **B**evacizumab (for stage III–IV).