EXPERIMENTAL HAEMOPOIETIC REPLACEMENT POSSIBLE USE IN RADIOTHERAPY

Abstract

The use of bone marrow and spleen cell grafts in recovery from radiation injury is discussed. It appears that following massive whole-body radiation in humans, efforts to repopulate marrow by means of homologous bone marrow grafting have been unsuccessful because the immune response between host and donor transplant has not been overcome. It would seem more feasible to extend the range of radio- and chemotherapy by concentrating on autologous bone marrow grafting, making use of recent improvements in very low temperature storage techniques. Mouse experiments show that the radiation doses required to eliminate all leukemic cells may exceed 2000 rad, and that such high doses injure nonhematopoietic tissues, especially intestinal mucosa, so that death results in spite of successful marrow grafting. In the case of human leukemia there is no satisfactory way to determine the degree of sensitivity of the leukemic cells to radiation. Also, there is no generally available means to deliver a uniform whole-body dose to human beings to ensure that leukemic cells in some areas do not survive. However, the principal obstacle to human marrow restoration after lethal irradiation remains the problem of secondary immunologic disease. Efforts to overcome these difficulties are discussed, including the use ofmore » multiple- source irradiation facilities, low-temperature storage of autologous remission marrow, and combined chemo- and radiotherapy. Successful treatment of a case of Hodgkin's disease by such combined therapy, with marrow infusion, is described. (BBB)« less