One important contribution during this period was the discovery of a means that allowed the administration of previously lethal doses of chemotherapy. The patients bone marrow was first harvested, the chemotherapy administered, and the harvested marrow then returned to patient a few days later. This approach, termed autologous bone marrow transplantation, was initially thought to be of benefit to a wide group of patients, including those with advanced breast cancer. However, rigorous studies have failed to confirm this benefit, and autologous transplantation is no longer widely used for solid tumors. The proven curative benefits of high doses of chemotherapy afforded by autologous bone marrow rescue are limited to both Hodgkins and selected non-Hodgkin's lymphoma patients who have failed therapy with conventional combination chemotherapy. Autologous transplantation continues to be used as a component of therapy for a number of other hematologic malignancies.