LOS ANGELES--Administration of cisplatin(Drug information on cisplatin) (Platinol) by the intraperitoneal rather than intravenous route to patients with optimally debulked stage III ovarian cancer reduced toxicity and improved survival by about 25%, David S. Alberts, MD, said at the ASCO meeting.
In this Intergroup study of 544 patients, the largest prospective phase III trial ever performed in ovarian cancer, median survival after more than 50 months of follow-up was 51 months on the IP arm vs 41 months on the IV therapy arm, a significant difference.
The IP to IV death hazard ratio was .75. "Thus, at any time during this study and its follow-up, there was a 25% greater likelihood of being alive if the patient was treated with IP therapy," said Dr. Alberts, deputy director, Arizona Cancer Center, Tucson. There were 171 deaths on the IV arm vs 143 on the IP arm.
Patients in the study had less than 2 cm residual tumor after primary surgery (more than 70% had less than 0.5 cm) and were stratified according to degree of residual disease and performance status before randomization.
They then received cisplatin, 100 mg/m², either IV or IP (in 2 liters of saline), plus IV cyclophosphamide(Drug information on cyclophosphamide), 600 mg/m², every 3 weeks for six cycles.
Patients on IP therapy had significantly less grade 3 or 4 neutropenia, which was not unexpected, since the peak plasma level of the drug is dramatically reduced with IP delivery. More IP patients had abdominal pain, but this was well controlled with narcotics.
The IP patients also had a significantly lower incidence of tinnitus and clinical hearing loss (5% clinical hearing loss of grade 2 or greater vs 14% on the IV arm).