A tissue positioning system for contouring a patient tissue volume includes an axially displaceable interface having a surface configured to engage a breast or other tissue volume. A low pressure source applies a partial low pressure to the surface of the displaceable interface to secure the tissue volume to the surface, and the axially displaceable interface is biased to pull and contour the tissue volume when the tissue volume is secured to the surface. The axially displaceable interface is typically mounted on a telescoping support and the biasing is provided by the same low pressure used to secure the tissue volume.
