Cytologic studies of tumors XLVII. Acute myelogenous leukemia with C/G translocation and differential response to PHA of normal and leukemic cells of blood and marrow

Some cytogenetic information obtained in a case of acute myelogenous leukemia associated with C/G translocation is presented here. Cells with a normal chromosome complement were present in PHA-added blood cultures, while blood cultures without PHA showed the occurrence of mitotic cells with C/G translocation at nearly 100 percent frequency. The majority of mitotic cells observed in direct bone marrow aspirates had a normal chromosome pattern. In the bone marrow cultured without PHA, the C/G cells occurred at the frequency of nearly 100 percent during 1 to 3 days in the early phase of the disease. Almost all mitotic cells in skin cultures gave a normal chromosome constitution. The mitotic frequency of the C/G cells showed a gradual decrease following chemotherapy along with the decrease of myeloblasts in the bone marrow. On the basis of the above findings, the C/G cells were interpreted as leukemic cells. The difference in frequency of cells with chromosome breakage was noted before and during chemotherapy, and the frequency was higher in the PHA-added blood cultures than in the non-PHA blood cultures. Some cytogenetic nature of the C/G leukemic cells in in vivo and in vitro conditions, and the effect of PHA on the cell in vitro growth are discussed.