A microbeam intraoperative, 10-50 kilovoltage radiation therapy system with multiple simultaneous microfocus X-ray sources and method for image guided, microsecond duration, 100 to 1,000 Gy microbeam radiation therapies with dose rate ranging from 1,000 to 20,000 Gy per second and RBE closer to high LET with minimal toxicity to normal tissue is provided. Dismountable coronal, sagital and transverse half-circle gantry sections are assembled on to a surgical table for mounting the microfocus X-ray sources for intraoperative radiosurgery. A stereotactic breast core biopsy system is adapted for combined breast biopsy, positron emission tomography and computerized tomography with phase-contrast imaging. Cosmetic whole breast preserving electronic brachytherapy is combined with stereotactic core biopsy. The low dose valley regions of the intersecting microbeams at the tumor site are filled with scattered and characteristic radiation from high Z-element that is bound or implanted into the tumor.
