After cytoreductive surgery for ovarian cancer, is a single‑infusion normothermic intraperitoneal chemotherapy (NIPEC) regimen preferable to the traditional multi‑infusion NIPEC schedule?

Single-Infusion NIPEC vs Traditional Multi-Infusion NIPEC Post-CRS in Ovarian Cancer

For stage III optimally debulked ovarian cancer after cytoreductive surgery, traditional multi-infusion intraperitoneal chemotherapy (6 cycles of IV paclitaxel day 1, IP cisplatin day 2, and IP paclitaxel day 8) remains the evidence-based standard when IP therapy is chosen, though single-infusion normothermic IP chemotherapy shows promise as an emerging alternative with lower toxicity.

Current Guideline-Based Standard

The established IP chemotherapy regimen consists of 1, 2:

• Paclitaxel 135 mg/m² IV continuous infusion over 24 hours on day 1
• Cisplatin 75-100 mg/m² IP on day 2 (after IV paclitaxel)
• Paclitaxel 60 mg/m² IP on day 8
• Repeated every 3 weeks for 6 cycles (Category 1 recommendation)

This traditional protocol demonstrated a 16-month survival advantage in GOG-172 (65.6 vs 49.7 months, P=0.03) 1. However, only 42% of patients completed all 6 cycles due to significant toxicity including leukopenia, infection, fatigue, renal toxicity, abdominal discomfort, catheter complications, and neurotoxicity 1.

The Case for Single-Infusion NIPEC

Evidence Supporting Single-Dose Approach

A recent prospective randomized study 3 evaluated single-dose normothermic IP chemotherapy administered for 24 hours post-CRS in 87 stage III patients:

Key findings:

• Disease-free survival: 28 months in IP chemotherapy groups vs 15 months in saline control (statistically significant)
• Cytology conversion: Post-IP samples showed 100% negative cytology in combination cisplatin+paclitaxel group
• Minimal morbidity: No major complications reported
• Comparable outcomes to HIPEC without the complexity and risks

Practical Advantages

Single-infusion NIPEC offers 3, 4:

• Simpler administration (one 24-hour infusion vs 6 multi-week cycles)
• Lower cumulative toxicity burden
• Reduced catheter-related complications
• Fewer treatment discontinuations
• Addresses microscopic peritoneal residue immediately post-surgery

Critical Context: The Evolving IP Landscape

Why Traditional IP Therapy Lost Favor

Despite survival benefits, multi-cycle IP chemotherapy never became standard of care because 5, 6:

• Greater toxicity compared to IV regimens
• Difficulty completing treatment (58% discontinuation rate in early studies)
• Catheter complications requiring additional procedures
• GOG-252 trial failure: Using lower cisplatin dose (75 mg/m²) with bevacizumab showed no PFS/OS improvement over IV therapy 2
• Most institutions consider it experimental, recommending use only in clinical trials 5

HIPEC as Alternative

Hyperthermic IP chemotherapy (HIPEC) has emerged as a competing single-administration approach 7, 8:

• OVHIPEC-1 trial: Showed PFS and OS benefit when added to interval cytoreductive surgery
• Administered intraoperatively (60-90 minutes at 41-43°C)
• However, concerns remain about imbalanced prognostic factors and lack of stratification for BRCA/HRD status 6
• Not considered standard therapy outside clinical trials 6

Clinical Decision Algorithm

When to Consider IP Therapy (Any Form)

Mandatory criteria 1, 2:

1. Stage III disease with <1 cm residual disease after optimal cytoreduction (ideally R0 resection)
2. Normal renal function at baseline
3. Good performance status to tolerate toxicity
4. No pre-existing neuropathy
5. High-grade serous, grade 2-3 endometrioid, or clear cell histology

Choosing Between Approaches

Traditional 6-cycle IP/IV regimen:

• Use when patient can tolerate aggressive therapy
• Requires experienced nursing care and close monitoring
• Mandatory IV hydration before/after each cycle
• Monitor for myelosuppression, renal toxicity, electrolyte imbalances
• Consider lower cisplatin dose (75 mg/m²) to reduce toxicity 1

Single-infusion NIPEC:

• Consider for patients who may not tolerate 6 cycles
• Addresses immediate microscopic disease burden
• Requires validation in larger prospective trials 3
• Currently investigational but shows promising DFS benefit

Standard IV therapy (carboplatin AUC 5-6 + paclitaxel 175 mg/m²):

• Remains the default for most patients 9, 6
• Less toxic, more convenient
• Addition of bevacizumab maintenance for high-risk patients (stage III with macroscopic residual or stage IV) 6

Critical Pitfalls to Avoid

1. Do not use IP therapy in patients with >1 cm residual disease—no survival benefit demonstrated 1

2. Do not assume HIPEC is standard—despite positive trials, it remains investigational due to methodological concerns 6

3. Ensure adequate hydration protocols with any IP cisplatin regimen—renal toxicity is preventable with proper fluid management 1, 2

4. Have low threshold to switch to IV therapy if catheter complications or intolerable toxicity develops 1

5. Do not use IP therapy after NACT/interval debulking unless in clinical trial—insufficient efficacy data despite feasibility studies 10

Bottom Line Recommendation

For optimally debulked stage III ovarian cancer, standard IV carboplatin/paclitaxel ± bevacizumab remains first-line therapy for most patients. If pursuing IP therapy, the traditional 6-cycle regimen has the strongest evidence base 1, though single-infusion NIPEC represents a promising lower-toxicity alternative that warrants consideration in appropriately selected patients, ideally within clinical trials 3. The choice depends on institutional expertise, patient tolerance for toxicity, and ability to complete multi-cycle therapy. HIPEC should only be offered in specialized centers within research protocols 6.