Paclitaxel an effective therapy for metastatic angiosarcoma of the breast

Results of a French study confirmed the safety and efficacy of weekly paclitaxel therapy for patients with metastatic or unresectable angiosarcoma and expanded the number of tumor types for which this therapy has been studied to include angiosarcoma of the breast.

“Soft tissue sarcomas need to be considered now as a very heterogeneous group of diseases,” Nicolas Penel, MD, PhD, of the University Lille in France, told HemOnc Today. “Angiosarcomas are very rare and are particularly sensitive to weekly paclitaxel.”

Thirty patients with metastatic or unresectable angiosarcoma received an 80 mg/m² dose of paclitaxel during a four-week cycle via 60-minute IV infusions on days one, eight and 15 for a maximum of six cycles.

The researchers observed a PFS rate of 74% among patients following the second cycle of paclitaxil therapy and a 45% PFS rate after the fourth cycle, data indicated.

OS rates were 56% at six months, 38% at 12 months and 21% at 18 months. Three patients with locally advanced breast angiosarcomas underwent curative-intent surgery following a partial response to the therapy after the second cycle, and two experienced a complete histologic response.

Anemia and fatigue were among the most frequently reported toxicities; however, six patients experienced grade-3 toxicity, one experienced a grade-4 toxicity and one patient died after an episode of thrombocytopenia.

“From a pragmatic point of view, we now have two different effective treatments for this aggressive and rare disease: doxorubicin and now weekly paclitaxel,” Penel said.

Another phase-2 French trial to evaluate sorafenib (Nexavar, Bayer) for this indication is ongoing, according to Penel. The researchers also are planning a biological analysis to determine predictive factors for response to weekly paclitaxel, Penel said. – by Nicole Blazek

J Clin Oncol. 2008; 26:5269-5274.

We reported single-agent weekly paclitaxel was active in patients with angiosarcoma of the scalp and face in the journal Cancer in 1999. In fact, this was the first report showing activity of this drug in angiosarcoma. We’ve been advocating paclitaxel therapy since that time at Memorial Sloan-Kettering Cancer Center, as have other medical oncologists who treat angiosarcoma, based on that original publication. This is generally accepted practice, at least among sarcoma specialists in the United States. This study does now confirm its use in breast cancer patients with angiosarcoma, as well as in the head and neck cancer patients that we first reported.

– Gary K. Schwartz, MD

Chief, Melanoma and Sarcoma Service

Memorial Sloan-Kettering Cancer Center