The role of chemotherapy in advanced solitary fibrous tumors: a retrospective analysis

BACKGROUND: Patients with advanced solitary fibrous tumors (SFTs) have a poor prognosis; treatment options for recurrent disease are particularly limited. Several novel targeted agents have recently shown promise against advanced SFTs, but the relative efficacy of new agents is difficult to assess because data on the efficacy of conventional chemotherapy for SFTs are limited. We thus sought to estimate the efficacy of conventional chemotherapy for SFTs by reviewing data on tumor response to therapy and progression-free survival from SFT patients who received this therapy. METHODS: We retrospectively analyzed the clinical outcomes of 21 patients with grossly measurable, advanced SFTs (unresectable metastatic disease or potentially resectable primary tumors) who received conventional chemotherapy and follow-up at The University of Texas MD Anderson Cancer Center between January 1994 and June 2007. Best tumor response to therapy was assessed using the Response Evaluation Criteria In Solid Tumors 1.1. The Kaplan-Meier method was used to estimate median progression-free survival (PFS) duration. RESULTS: Of 21 patients, 4 received more than 1 regimen of chemotherapy, for a total of 25 treatments. Doxorubicin-based chemotherapy was given in 15 cases (60%), gemcitabine-based therapy in 5 cases (20%), and paclitaxel in 5 cases (20%). First-line chemotherapy was delivered in 18 cases (72%). No patients had a complete or partial response, 16 (89%) had stable disease, and 2 (11%) had disease progression. Five patients (28%) maintained stable disease for at least 6 months after first-line treatment. The median PFS duration was 4.6 months. The median overall survival from diagnosis was 10.3 years. CONCLUSION: Conventional chemotherapy is effective in controlling or stabilizing locally advanced and metastatic SFTs. Our findings can serve as a reference for tumor response and clinical outcomes in the assessment of novel treatments for SFTs.