Method of assembly and whole body, patient positioning and repositioning support for use in radiation beam therapy systems

A whole-body patient positioning and repositioning support for fixedly securing a patient in an original position during radiation treatment and for repositioning the patient to the same original position for subsequent radiation treatments. The support includes a foamed-in-place mold within a disposable plastic shell carrying a grid of radio-opaque members for generating a patient registration grid on X-rays for use in the evaluation and adjusting of the position of the patient to the original position using a sheet or straps between the patient and the mold.