A 52-year-old woman undergoes staging laparotomy for epithelial ovarian cancer. Intraoperatively, she is found to have a 6 cm left ovarian mass with 200 mL of clear ascites, omental involvement, and a single 2 cm peritoneal implant on the pelvic sidewall. The surgeon achieves complete cytoreduction with no residual disease >1 cm. Postoperatively, she receives 6 cycles of carboplatin (AUC 5) and paclitaxel (175 mg/m²). At 18 months post-treatment, CA-125 rises from 8 U/mL to 45 U/mL, and imaging shows a 3 cm pelvic mass. What is the most appropriate next step?

Explanation

## Clinical Context: Platinum-Sensitive Recurrence This patient has **platinum-sensitive recurrent ovarian cancer** (PSROC): - Initial complete response to platinum-based chemotherapy - Recurrence >6 months after completing first-line therapy (18 months in this case) - Biochemical and radiological evidence of recurrence (elevated CA-125, new pelvic mass) **Key Point:** Platinum-sensitive recurrence is defined as recurrence ≥6 months after the last platinum dose. These patients benefit from re-challenge with platinum-based chemotherapy. ## Treatment of Platinum-Sensitive Recurrent Ovarian Cancer | Feature | Platinum-Sensitive | Platinum-Resistant | |---------|-------------------|-------------------| | Time to recurrence | ≥6 months | <6 months | | First-line therapy | Platinum-based chemotherapy | Platinum-based chemotherapy | | **Standard re-treatment** | **Carboplatin + paclitaxel ± bevacizumab** | Non-platinum agents (topotecan, liposomal doxorubicin, gemcitabine) ± bevacizumab | | Prognosis | Better (median OS 12–24 months) | Worse (median OS 6–12 months) | | Surgical debulking | Consider if optimal resection feasible | Generally not recommended | **High-Yield:** The standard of care for PSROC is **re-induction chemotherapy with carboplatin + paclitaxel**, with the addition of bevacizumab improving progression-free survival (AURELIA trial, GOG-213 trial). ## Management Algorithm for Recurrent Ovarian Cancer ```mermaid flowchart TD A[Recurrent ovarian cancer]:::outcome --> B{Time since last platinum?}:::decision B -->|≥6 months<br/>Platinum-sensitive| C[Carboplatin + Paclitaxel<br/>± Bevacizumab]:::action B -->|<6 months<br/>Platinum-resistant| D[Non-platinum agents:<br/>Topotecan, liposomal doxorubicin,<br/>gemcitabine ± Bevacizumab]:::action C --> E{Optimal debulking<br/>possible?}:::decision E -->|Yes| F[Consider interval<br/>debulking surgery]:::action E -->|No| G[Chemotherapy alone]:::action D --> H[Palliative chemotherapy<br/>or clinical trial]:::action ``` **Clinical Pearl:** Bevacizumab (anti-VEGF monoclonal antibody) is now standard in PSROC when combined with chemotherapy. It improves PFS by ~4 months and is particularly beneficial in patients with ascites or high tumor burden. **Warning:** Observation alone or bevacizumab monotherapy is not appropriate for PSROC. Platinum-sensitive disease should be re-challenged with platinum-based therapy, as these patients retain chemosensitivity. ## Evidence Base - **AURELIA trial**: Bevacizumab + chemotherapy vs. chemotherapy alone in recurrent ovarian cancer → improved PFS with combination - **GOG-213 trial**: Bevacizumab + chemotherapy + maintenance bevacizumab in PSROC → improved PFS and OS [cite:Williams Gynecology 4e Ch 32; NCCN Ovarian Cancer Guidelines 2023]