Abstract: | Twenty-six patients with acute myeloid leukemia, acute lymphoid leukemia and chronic granulocytic leukemia in blast crisis were studied by means of multiple biopsies during a polychemotherapeutic or autologous bone marrow transplant protocol. Following chemotherapy, 3 main phases were observed: leukemic cellular depletion, stromal bone marrow reconstruction, and bone marrow hemopoietic restoration. Following intensive chemotherapy (in 2 patients after cyclophosphamide and total body irradiation) and autologous bone marrow transplantation, the 3 phases appeared to be shorter. A focal or diffuse increase in marrow fibrosis was a common finding in leukemia. An effective antileukemic therapy resulted in a decrease in fibrosis, whereas in some cases a further increase was a precocious sign of leukemia relapse. |