The variant form of acute promyelocytic leukaemia (AML-M3) possesses its own characteristic morphology, although usually a few of the cells may have cytoplasmic features of typical AML-M3. In contrast to typical AML-M3, this M3-variant form commonly presents with hyperleucocytosis. As in typical AML-M3, disseminated intravascular coagulopathy (DIVC) occurs in the M3-variant. A boy with this morphological variant of AML-M3 is described. Uncharacteristically, his presenting white blood count was low, and DIVC was present before treatment was started. Six days into intensive chemotherapy his coagulopathy worsened and he subsequently died of intracranial haemorrhage. An alternative approach to the treatment of AML-M3, with the use of retinoids, is discussed.
Intense myelofibrosis is rarely associated with de novo acute myeloid leukaemia (AML) except in acute megakaryoblastic leukaemia (AML-M7) where there is diffuse marrow fibrosis as a consequence of proliferation of neoplastic myeloid cells. AML associated with significant myelofibrosis developing both de novo or secondary to primary (idiopathic) myelofibrosis is characterised by a fulminant course and extremely poor prognosis, primarily due to treatment-resistant disease. The prognostic value of degree of marrow fibrosis in de novo AML has been poorly investigated. We describe a case of extensive myelofibrosis associated with acute erythroblastic leukaemia (AML-M6) that responded to induction therapy of the leukaemia.
Acute promyelocytic leukemia (APL) in pregnancy poses serious danger to both the mother and fetus. Cytotoxic chemotherapy may cause teratogenicity to the fetus. APL is unique because it is usually associated with a coagulopathy that markedly increases the risk for the mother and fetus. A 21 year old lady with APL in her third trimester of pregnancy was treated with oral tretinoin. Tretinoin reversed the coagulopathy and normalised her blood counts without causing cytotoxic damage associated with cancer chemotherapy. Fetal distress occurred at 37 weeks of gestation and an emergency caesarean section was performed without complications and no blood transfusion support was needed as her coagulopathy and thrombocytopenia had resolved. A remission was achieved with only tretinoin induction. She subsequently had consolidation and maintenance chemotherapy. The mother and baby remain well at 4 years from completion of chemotherapy. A total of 10 pregnancies associated with APL have been reported in the current literature. Premature delivery and a fetal arrhythmia were the only complications. Although retinoin is considered teratogenic, its use so far in second and third trimester has been safe.