Kinetics of 111In-labelled leukaemic cells in blast crisis of chronic myelocytic leukaemia.

: The distribution within the body of autologous leukaemic cells labelled with 111In oxine was studied in 4 patients with blast crisis of chronic myelocytic leukaemia (CML) by means of serial samples and gamma camera imaging. Leukaemic cells of the blood initially entered the spleen and liver, and the major site of localization was the former rather than the latter. A portion of leukaemic cells, which rapidly entered the liver, left temporarily 3 h after reinjection. Leukaemic cells entered the spleen maximally at 3 or 24 h and then continued to leave gradually or rapidly up to 48 h. The majority of leukaemic cells in acute myelocytic leukaemia did not leave the spleen for up to 48 h. It is suggested that the destruction of sinusoidal structures of the spleen due to marked infiltration of leukaemic cells in CML impairs the effects of filtration in endothelial cells of sinusoids and facilitates the entry of leukaemic cells into sinusoids from splenic cords.