A Phase II Study of Tumor Ablation in Patients with Metastatic Sarcoma Stable on Chemotherapy.

LESSONS LEARNED: Ablation therapy appears to be a reasonably safe and effective approach to obtain a significant treatment-free interval for a subset of patients with limited sites of metastatic disease for which systemic control can be obtained with six cycles of chemotherapy. BACKGROUND: Metastatic sarcoma often becomes resistant to treatment by chemotherapy. There is sometimes prolonged stable disease from active chemotherapy that provides a window of opportunity for an intervention to prolong disease-free survival. MATERIALS AND METHODS: We performed a phase II study in patients with metastatic sarcoma who had been stable on six cycles of chemotherapy who then received ablation therapy to their residual disease. Histologies captured in this study included leiomyosarcoma, malignant peripheral nerve sheath tumor, pleiomorphic rhabdomyosarcoma, and myxoid liposarcoma. Sites ablated included lung metastases and retroperitoneal metastatic deposits. In this study, up to three lesions were ablated in any given interventional radiology session. After ablation, patients were not treated with any further therapy but were followed by surveillance imaging to determine progression-free rate (PFR). RESULTS: Although terminated early because of slow accrual, this study demonstrated a 3-month PFR of 75% for this cohort of eight patients treated with ablation performed after completion of six cycles of chemotherapy with stable disease. Median progression-free survival (PFS) was 19.74 months, and the median overall survival (OS) was not reached. CONCLUSION: Our data are the first prospective study to suggest that ablation therapy in selected patients who are stable on chemotherapy can provide a significant progression-free interval off therapy and warrants further study in a randomized trial.

Phase II study of dacarbazine given with modern prophylactic anti-emetics and growth factor support to patients with metastatic, resistant soft tissue, and bone sarcoma.

Historically, administration of dacarbazine to sarcoma patients was limited by frequent treat-ment-related nausea/vomiting and neutropenia. These toxicities are now largely preventable with contemporary antiemetics and growth factor support. In this single-arm, phase II study, dacarbazine 850 mg/m2 was given on day 1 of each 3-week cycle until disease progression or intolerance with prophylactic serotonin-3 receptor, neurokinin-1 antagonists, corticosteroids, and pegfilgrastim. Coprimary endpoints included clinical benefit rate (CBR), and any grade of nausea/vomiting and/or grade 3-4 neutropenia. With a sample size of 80 patients, >24 patients with clinical benefit would indicate that the CBR exceeds the historical (<20%) [Power 0.80; alpha 0.05]. In addition, we hypothesized that the rates of nausea/vomiting would be 27% and grade 3-4 neutropenia would be 1% (historical: 90% and 36%, respectively) [power 0.95; alpha 0.05]. The CBR was 30% (24 patients: PR-2 and stable-22). The rate of nausea/vomiting was 37.5% (31 patients) and grades 3-4 neutropenia was 10% (8 patients). Median time-to-progression was 8.1 weeks (95% CI 8-9.7) and median overall survival was 35.8 weeks (95% CI 26.2-55.4). PET scans demonstrated no association with response. Modern prophylactic anti-emetics and pegfilgrastim given with dacarbazine reduced the rates of treatment related nausea/vomiting and serious neutropenia.

Interim Analysis of the Phase II Study: Noninferiority Study of Doxorubicin with Upfront Dexrazoxane plus Olaratumab for Advanced or Metastatic Soft-Tissue Sarcoma.

PURPOSE: To report the interim analysis of the phase II single-arm noninferiority trial, testing the upfront use of dexrazoxane with doxorubicin on progression-free survival (PFS) and cardiac function in soft-tissue sarcoma (STS). PATIENTS AND METHODS: Patients with metastatic or unresectable STS who were candidates for first-line treatment with doxorubicin were deemed eligible. An interim analysis was initiated after 33 of 65 patients were enrolled. Using the historical control of 4.6 months PFS for doxorubicin in the front-line setting, we tested whether the addition of dexrazoxane affected the efficacy of doxorubicin in STS. The study was powered so that a decrease of PFS to 3.7 months would be considered noninferior. Secondary aims included cardiac-related mortality, incidence of heart failure/cardiomyopathy, and expansion of cardiac monitoring parameters including three-dimensional echocardiography. Patients were allowed to continue on doxorubicin beyond 600 mg/m2 if they were deriving benefit and were not demonstrating evidence of symptomatic cardiac dysfunction. RESULTS: At interim analysis, upfront use of dexrazoxane with doxorubicin demonstrated a PFS of 8.4 months (95% confidence interval: 5.1-11.2 months). Only 3 patients were removed from study for cardiotoxicity, all on > 600 mg/m2 doxorubicin. No patients required cardiac hospitalization or had new, persistent cardiac dysfunction with left ventricular ejection fraction remaining below 50%. The median administered doxorubicin dose was 450 mg/m2 (interquartile range, 300-750 mg/m2). CONCLUSIONS: At interim analysis, dexrazoxane did not reduce PFS in patients with STS treated with doxorubicin. Involvement of cardio-oncologists is beneficial for the monitoring and safe use of high-dose anthracyclines in STS.See related commentary by Benjamin and Minotti, p. 3809.