Clinical benefit and tolerability of adjuvant intraperitoneal chemotherapy in patients who have or have not received neoadjuvant chemotherapy for advanced ovarian cancer

BACKGROUND: Adjuvant chemotherapy using intraperitoneal (IP) treatment has demonstrated survival benefit over intravenous (IV) therapy alone in patients treated with upfront debulking surgery for advanced stage ovarian cancer. Neoadjuvant chemotherapy followed by interim surgery and adjuvant chemotherapy has similar outcome in survival as compared to upfront surgery followed by adjuvant IV chemotherapy. IP chemotherapy has not been widely adopted in clinical practice for a number of reasons. Whether IP chemotherapy delivered in the patients who received neoadjuvant chemotherapy can be well tolerated or confers any clinical benefit has not been well studied. AIM: To evaluate the experience of adjuvant IP chemotherapy in the community cancer clinic setting, and the clinical benefit and tolerability of incorporating IP chemotherapy in patients who received neoadjuvant treatment. METHODS: We retrospectively evaluated toxicities and outcomes of patients with stage III and IV ovarian cancer diagnosed at our institution between 07/2007 and 07/2015 who received intraperitoneal chemotherapy after cytoreductive surgery (group 1) or after neoadjuvant chemotherapy followed by interim surgery (group 2). RESULTS: Thirty eight patients were treated with IP chemotherapy, median age was 54 years old (range 38.6 to 71 years). In group 1 (n = 25), 12 (48%) of the patients completed 4 or more cycle of IP treatment after upfront debulking surgery; while in group 2 (n = 13), 8 (61.5%) of the patients completed all 3 cycles of the assigned IP chemotherapy after receiving neoadjuvant IV chemotherapy followed by surgery, and 2 (15.4%) more patients tolerated more than 3 cycles. In those patients who did not get planned IP chemotherapy, most of them were treated with substitutional IV chemotherapy, and the completion rate for 6 cycles of IV + IP was 92%. Abdominal pain, (64% in group 1 and 38% in group 2), vomiting, (36% in group 1 and 30.8% in group 2), dehydration (16% in group 1 and 15.4% in group 2), and hypomagnesemia (12% in group 1 and 15.4% in group 2) were the most common adverse effects in all patients, while patients who have received neoadjuvant chemotherapy were more likely to get hypokalemia, fatigue and renal insufficiency. Progression free survival (PFS) was 26.5 mo (95% CI 14.9, 38.0) in group 1 and 27.6 mo (95% CI 13.1, 42.1) in group 2. The overall survival was 100.2 mo (95% CI 67.9, 132.5) for group 1 and 68.2 mo (95% CI 32.2, 104.0) for group 2. For the entire cohort, PFS was 26.5 mo (95% CI 15.9, 37.0) and OS was 78.8 mo (95% CI 52.3, 105.4). CONCLUSION: The use of IP/IV chemotherapy can be safely administrated in the community cancer clinic setting. The use of IP/IV chemotherapy in patients who have received neoadjuvant chemotherapy followed by surgery is feasible and tolerable. Despite various modification of the IP regimen, incorporation of IP chemotherapy in the adjuvant setting appears to be associated with improved PFS and overall survival.