Abstract
The fine structure of the leukemic cells from seven cases of acute promy-elocytic leukemia was described, and compared with that of the promyelocytes from acute myeloblastic leukemia and the leukemic cells from monocytic leuke-mia.
The fibrin-like structure, which has never been reported, was seen in the rough-surfaced endoplasmic reticulum of the leukemic cells.
The common features of the leukemic cells of this type included well de-veloped rough-surfaced endoplasmic reticulum, lysosomes and Golgi apparatus, large mitochondria and fibrillar formation near the nucleus.
