Varian Medical Systems Inc., of Palo Alto, Calif., continues its recent spending spree, reporting Tuesday that it has signed an agreement to acquire Marlborough, Mass.-based Boston Scientific Corp.'s line of embolic bead products for $90 million. The proposed purchase of the drug-loadable microsphere and bland embolic bead portfolio comes on the heels of Varian's June acquisitions of Austin-based Endocare Inc. and Hangzhou, China-based Alicon, and aims to boost Varian's footprint in the global interventional oncology market.