Autopsy data on 1,206 children and adult patients with acute myelocytic leukemia (AML) (585), chronic granulocytic leukemia (CGL) (204), acute lymphocytic leukemia (ALL) (308), and chronic lymphocytic leukemia (CLL) (109) obtained from 1958 to 1982 were reviewed. This analysis has shown that, whereas the proportion of patients with residual AML at any anatomic site decreased significantly and uniformly over the entire study period, significant corresponding decreases in patients with CGL and ALL occurred only since 1976 and 1978, respectively. No significant corresponding decreases were noted in patients with CLL at any time. Significant decreases were also noted over time in the rates of extramedullary site involvement by AML, CGL, and ALL. Whereas the lymphoreticular organs, kidneys, adrenals, and pituitary were most often involved at autopsy by CLL, the testes, leptomeninges, dura mater, uterus, large bowel, and pancreas were most often involved by ALL. In general, patients with AML and CGL showed the lowest relative rates of involvement of the various organs by leukemia during the 24-year period. Whereas patients with AML and ALL showed significant decreases in the rates of involvement of nearly all anatomic sites during the most recent study periods, those with CGL and CLL showed corresponding decreases in only a few organ sites. The lower rates of organ involvement in patients with AML and ALL attest to the more aggressive eradication of leukemic cells by therapeutic regimens in these diseases over time. In particular, the significant decrease in the rate of meningeal involvement by ALL during the most recent period is probably attributable to central nervous system prophylaxis.

DMSO and other cryoprotective agents produce a pronounced increase on the phase transition temperature of phospholipid membranes, indicating an increased stability. The effects of DMSO and other cryoprotective agents, divalent cations, and local anaesthetics on the transition temperature of phospholipid membranes seem to correlate with their effects on the differentiation of Friend leukaemic cells in vitro. These studies suggest that the induction of differentiation by cryoprotective agents may be the result of the interaction of these agents with cell membranes.

Despite hypercellular bone marrows (BM), peripheral cytopenias are the rule in patients with myelodysplastic syndromes (MDS). This study examined the roles played by cell birth and cell death rates in generating this paradox. Cell kinetics from BM biopsies of 35 MDS patients were measured using intravenous infusions of either iododeoxyuridine or bromodeoxyuridine, or both. Degree of apoptosis or programmed cell death (PCD) was estimated using in situ end-labeling of DNA directly from BM biopsies, which were simultaneously double-labeled from proliferation/PCD. MDS were found to be highly proliferative disorders with large numbers of myeloid, erythroid, and megakaryocytic cells synthesizing DNA. Median cycling time (Tc) of myeloblasts was more rapid than that of patients with acute myeloid leukemia (44.1 hr vs. 56.0 hr). Interestingly, most marrow cells of all three lineages in 32 of 34 evaluable cases were undergoing PCD. In 19 of 32 patients, greater than 75% cells were apoptotic. Surprisingly, large numbers of S-phase cells were found to be simultaneously undergoing PCD, as were stromal cells of the BM microenvironment. We conclude that the extensive apoptosis in hematopoietic cells effectively cancels the high birth rate resulting in ineffective hematopoiesis and accounting for deficient bone marrow function.

Leukemia cutis was documented by biopsy in 18 of 877 patients (2%) with acute myelogenous leukemia (AML) seen at Roswell Park Memorial Institute (Buffalo, NY) between 1969 and 1986. French-American-British (FAB) types included four M2, one M3, ten M4, and three M5. Lysozyme was more consistently detectable in skin sections in our cases than Leu-M1, alpha-1-antitrypsin, alpha-1-antichymotrypsin, or chloroacetate esterase activity. Additional extramedullary sites of involvement were present in 16 patients, including meningeal leukemia in six. Two patients had leukemia cutis preceding bone marrow leukemia. Skin was the initial site of relapse in 11 patients, without marrow relapse, occurring as late as 5.5 years after diagnosis. Most patients in this retrospective series were treated with radiation therapy and/or palliative chemotherapy, and did poorly, with prompt bone marrow relapses and serial skin relapses. Long-term disease-free survival was achieved in the one patient whose skin relapse was treated with whole-body electron-beam radiation therapy in conjunction with reinduction and consolidation chemotherapy. Severe skin toxicity was caused by administration of Adriamycin (doxorubicin) 12 days after electron-beam irradiation in one patient, but was not seen when cytosine arabinoside was administered in doses up to 3 g/m2 in conjunction with radiation therapy. This retrospective review suggests that optimal management of AML involving skin might include whole-body electron-beam irradiation in conjunction with induction or reinduction chemotherapy without anthracyclines, followed by consolidation chemotherapy. Additionally, there should be ongoing surveillance for and treatment of extramedullary disease at other sites, including the meninges.

The expression of the MDR1 gene was studied by Northern blot analysis in leukaemic cell specimens obtained from 74 patients with acute myelogenous leukaemia (AML). No relationship was found between MDR1 RNA levels and FAB type of leukaemia or patient age. Transcript levels tended to be highest in the leukaemic cells of patients with a history of toxic exposure or preleukaemia compared with 'standard risk' patients at diagnosis but the differences were not significant (P = 0.07). Patients whose leukaemic cells contained high MDR1 transcript levels were difficult to induce into remission and, if remission was induced, the remissions were short. Hence high levels of MDR1 expression may explain, at least in part, the ineffectiveness of anthracycline antibiotic containing treatment regimens in some patients with AML.