Varian Medical Systems Inc. and Proxima Therapeutics Inc. this week solidified an alliance to increase access to high-dose-rate (HDR) radiation therapy equipment for hospitals interested in offering partial breast irradiation to patients with early-stage breast cancer.

Under the terms of the agreement, Proxima will become the exclusive third-party representative for Varian's recently FDA-cleared MammoSource HDR brachytherapy afterloader, developed specifically to work with Proxima's MammoSite device for treating breast cancer with localized HDR brachytherapy. Varian's MammoSource afterloader will be made available to treatment centers on a fee-for-use basis, subject to minimums.

According to Varian, the MammoSource afterloader is more affordable than traditional HDR afterloaders, which incorporate up to 24 channels for delivering more complex forms of brachytherapy. Varian developed the MammoSource HDR afterloader to deliver radiation through a single channel, consistent with MammoSite's single balloon catheter design. MammoSource is powered by Varian's BrachyVision software, HDR brachytherapy treatment planning system.