High-Dosage Chemotherapy Several new and exciting programs for high-dosage chemotherapy are now being tested in major cancer centers. The hope is that greatly increased dosages may cure some malignancies that may not be curable with standard dosages. Various supportive measures may be used with these programs to decrease the toxic effects of the higher dosages, although in some cases, it is known that increased dosages may be given without the need for additional measures.
A very aggressive supportive measure is removing early blood-forming cells— called stem cells—from the body before very high dosage chemotherapy is given. These stem cells are preserved, then reinjected to re-establish normal blood production and blood counts. This procedure used to be called bone marrow transplantation. A more appropriate term is bone marrow protection.
In cases of heart, liver or lung transplants or in the case of bone marrow transplanted to patients with acute leukemia, the transplanted tissue takes over and replaces the diseased tissue or cancer-affected normal organ. In the case of high-dosage chemotherapy, the early blood-forming cells do not replace any diseased tissue. The anticancer treatment is the chemotherapy, not the removal and reinjection of early blood cells .
With special equipment, stem cells can now be removed from veins. Although bone marrow may also be collected as a backup, many high-dosage chemotherapy programs depend primarily on stem cell protection. Research is determining the role of high-dosage chemotherapy with stem cell protection in treating several potentially curable malignancies. ( See also Bone Marrow Transplantation .)
