Pure acute monocytic leukemia. A study of 12 cases.

Twelve cases of pure acute monocytic leukemia in adults were studied. They were selected on the basis of the morphology of the blast cells on Romanowsky-stained smears of blood and bone marrow, as well as positivity of the cells for the naphthol ASD acetate esterase reaction specifically inhibited by sodium fluoride. There was no sex predominance. Neoplastic involvement of the skin and/or gingiva was very frequent. The leukemic proliferation in blood and bone marrow consisted of monoblasts, promonocytes and monocytes. The peroxidase reaction was negative or only faintly positive. Serum and urinary lysozyme levels were increased. The blast cells retained their ability to stimulate, in vitro, colony formation by normal bone marrow cells used as targets. All of these characteristics permit specific identification of this type of acute leukemia. The prognosis is grim: only five of 12 patients achieved complete remission, and four of these five had relapses in less than 14 months; the median survival was five months.

[Granulocytic progenitors in bone marrow autografts]. / Apport de l'étude des progéniteurs granulocytaires (CFC) dans les auto-greffes de moelle osseuse.

Granulocytic progenitor cells (CFC) are a better reflection of stem cell pools than precursors. Their total number can be estimated during hematologic steady-state (N = 70 +/- 29 x 10(5) CFC/kg); the amount of marrow necessary to perform a bone marrow transplantation is only 1% of the total pool. CFC are useful but have a mainly qualitative value in evaluating the viability of marrow stored for 24 h at room temperature (92%) or marrow thawed after DMSO cryopreservation (62%). Sequential study of CFC in patients receiving autologous marrow transplantation enables differentiation of engraftment from autologous recovery. In 11 recipients of autologous marrow transplantation, no statistical relation was observed between number of infused CFC and severity of granulocytopenia. Further studies will be necessary to evaluate a better marker of real hematopoietic stem cells.