What is the management approach for ovarian cancer with peritoneal carcinomatosis?

Management of Ovarian Cancer with Peritoneal Carcinomatosis

Primary Treatment Strategy

Maximal cytoreductive surgery followed by platinum-taxane chemotherapy is the cornerstone of management for ovarian cancer with peritoneal carcinomatosis, with the goal of achieving complete resection of all visible disease. 1

Surgical Management

Primary cytoreductive surgery should be performed by a gynecologic oncologist (Category 1 recommendation) and must include:

• Total abdominal hysterectomy and bilateral salpingo-oophorectomy 1
• Complete omentectomy (removal of all involved omentum) 1
• Aspiration of ascites or peritoneal washings for cytologic examination 1
• Bilateral pelvic and para-aortic lymph node dissection (especially for stage IIIB disease with tumor nodules ≤2 cm outside pelvis) 1
• Resection of all visible disease with maximal effort to achieve no residual disease 1

Extended cytoreductive procedures that may be necessary include: 1

• Radical pelvic dissection
• Bowel resection
• Diaphragm or peritoneal surface stripping
• Splenectomy
• Partial hepatectomy
• Cholecystectomy
• Partial gastrectomy or cystectomy
• Ureteroneocystostomy
• Distal pancreatectomy

Optimal cytoreduction is defined as residual disease <1 cm, though complete resection of all gross disease should be the primary goal. 1

Neoadjuvant Chemotherapy Option

Neoadjuvant chemotherapy followed by interval debulking surgery may be considered for: 1

• Patients with bulky stage III-IV disease who are not surgical candidates
• Patients with high perioperative risk
• Patients with low likelihood of achieving optimal cytoreduction at primary surgery

Important caveat: The EORTC trial showed equivalent median overall survival (29-30 months) between neoadjuvant chemotherapy with interval debulking versus primary debulking, but with fewer complications in the neoadjuvant group. However, these survival outcomes were inferior to U.S. trials reporting 50-month median survival with primary debulking. 1 Pathologic diagnosis must be confirmed (FNA, biopsy, or paracentesis) before initiating neoadjuvant chemotherapy. 1

Interval Debulking Surgery

If initial maximal cytoreduction was not performed, interval debulking surgery should be considered in patients responding to chemotherapy or showing stable disease. 1 IDS should ideally be performed after 3 cycles of chemotherapy, followed by 3 additional cycles. 1

Systemic Chemotherapy

Standard First-Line Regimen

The recommended standard chemotherapy for advanced ovarian carcinoma (stages IIb-IIIc and IV) is: 1

• Carboplatin AUC 5-7.5 plus paclitaxel 175 mg/m² over 3 hours every 3 weeks for 6 cycles 1

Intraperitoneal Chemotherapy

Patients with low-volume residual disease after surgical cytoreduction are potential candidates for intraperitoneal therapy. 1 Consider placement of an intraperitoneal catheter at initial surgery in these patients. 1

Platinum-Resistant Recurrent Disease

For platinum-resistant recurrent epithelial ovarian cancer with peritoneal carcinomatosis, bevacizumab is FDA-approved: 2

• 10 mg/kg intravenously every 2 weeks in combination with paclitaxel, pegylated liposomal doxorubicin, or topotecan (weekly) 2
• 15 mg/kg intravenously every 3 weeks in combination with topotecan (every 3 weeks) 2
• Indicated for patients who received no more than 2 prior chemotherapy regimens 2

Response Monitoring

CA-125 levels should be performed prior to each cycle of chemotherapy, as they accurately correlate with tumor response and survival. 1

CT scan imaging strategy: 1

• Repeat CT after cycle 6 for patients with abnormal baseline CT (unless CA-125 indicates non-response, warranting earlier imaging)
• Interim CT after 3 cycles should be considered for CA-125 negative patients or when interval debulking surgery is being considered
• Patients with normal baseline CT do not need further CT scans unless clinical or biochemical progression occurs

Current data do not support maintenance/consolidation treatment beyond 6 cycles. 1 However, patients with partial response or elevated CA-125 after 6 cycles but continuing evidence of response may receive 3 additional cycles of the same chemotherapy. 1

Emerging Approaches for Recurrent Disease

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is an emerging minimally invasive approach for platinum-resistant recurrent ovarian cancer with peritoneal carcinomatosis. 3 Early results show median overall survival of 15.13 months with approximately 20% of patients becoming candidates for secondary cytoreductive surgery, though larger randomized trials are needed. 3

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC) has shown promising results in selected patients with peritoneal carcinomatosis, achieving 5-year survival of 16.7% with acceptable morbidity when optimal cytoreduction (CC score 0-1) is achieved. 4

Critical Pitfalls to Avoid

• Do not delay treatment for genetic counseling referral, as delay is associated with poorer outcomes 5
• All patients should undergo genetic risk evaluation and BRCA1/2 testing to inform maintenance therapy options 5
• Up to 40% of patients may be understaged when comprehensive staging is not performed 5
• "Second-look" surgery following completion of chemotherapy in patients in complete remission should only be undertaken as part of a clinical trial, as there is no evidence for survival benefit 1

Follow-up Schedule

Surveillance should include: 1

• History and physical examination including pelvic examination every 3 months for 2 years
• Every 4 months during year 3
• Every 6 months during years 4-5 or until progression