Introduction
Despite effective local therapy with surgery and radiation (RT), approximately 50% of patients with high grade soft tissue sarcoma (STS) will relapse and die of disease. Since experimental data suggest a significant synergistic effect when anti-angiogenic targeted therapies, such as sorafenib, are combined with RT, we chose to evaluate preoperative combined modality sorafenib and conformal RT in a Phase I/II trial among patients with extremity STS amenable to treatment with curative intent.
Methods
For the Phase I trial, eight patients with intermediate or high grade STS > 5 cm in maximal dimension or low grade STS > 8 cm in maximal dimension received concomitant sorafenib (dose escalation cohort 1:200 bid, cohort 2:200/400 daily) and preoperative RT (50 Gy in 25 fractions). Sorafenib was continued during entire period of RT as tolerated. Surgical resection was completed four to six weeks following completion of neoadjuvant sorafenib/RT. Three sorafenib dose levels were planned. Primary endpoints of the Phase I trial were maximal tolerated dose and dose-limiting toxicity (DLT).
Results
Eight patients were enrolled in the Phase I (5 female, median age 44, 3 high grade pleomorphic, 2 myxoid/round cell liposarcoma, 3 other). Median tumor size was 16 cm (range 8–29), and all tumors were located in the lower extremity. Two of 5 patients treated at dose level 2 developed DLT consisting of grade 3 rash not tolerating drug reintroduction. Other grade 3 side effects included anemia, perirectal abscess, and SVT. Radiation toxicity (grade 1 or 2 dermatitis, N=8) and post-surgical complications (3 grade 3 wound complications) were comparable to historical controls and other series of preoperative RT monotherapy. Complete pathologic reponse (≥ 95% tumor necrosis) was observed in 3 patients (38%).
Conclusion
Neoadjuvant sorafenib in combination with RT is tolerable and appears to demonstrate activity in locally advanced extremity STS. Further study to determine efficacy at dose level 1 is warranted. (NCT#00805727, ClinicalTrials.gov)