A phase II trial of irinotecan in patients with advanced or recurrent endometrial cancer and correlation with biomarker analysis

Abstract Objective Chemotherapy for advanced or recurrent endometrial cancer requires further development. Irinotecan hydrochloride (CPT-11) suppresses tumor growth in several endometrial cancer strains. The present study evaluated the anti-tumor activity and toxicity of CPT-11 in patients with advanced or recurrent endometrial cancer. Methods Enrolled patients had advanced endometrial cancer with measurable lesions and received 2 pretreatment regimens. A 90-minute intravenous infusion of CPT-11 (100 mg/m 2 ) was given on days 1, 8, and 15 of a 4-week cycle, aiming for an effect with ≤2 cycles. Treatment was continued until the primary disease worsened or severe toxicity occurred. The primary endpoint was response rate, and the secondary endpoints were progression-free survival, overall survival, and adverse events. Antitumor effect and adverse events were evaluated according to RECIST version 1.1 and NCI-CTC AE version 3.0, respectively. Results Twenty-two patients were registered (11 endometrioid carcinomas and 11 serous carcinomas). The median duration of the treatment-free interval (TFI) was 7.5 months, and the median number of administered cycles per patient was 4. Response rate was 36.4% (complete response: 1 patient, partial response: 7 patients). Clinical benefit rate, including stable disease, was 77.3%. Median progression-free and overall survival was 4.4 and 18.4 months, respectively. Observed adverse events included grade 4 hematotoxicity (neutropenia and thrombocytopenia), and grade 2 or 3 non-hematotoxicity (diarrhea). All adverse events were manageable. Biomarker predictors of therapeutic effectiveness were not observed. Conclusion As a single agent, CPT-11 has anti-tumor activity for advanced or recurrent endometrial cancer and has manageable adverse events.