Characterizing PML/RARα Isoforms of Acute Promyelocytic Leukemia (APL) in Malay patients.

Aim: Reciprocal translocation between retinoic acid receptor alpha (RARα) gene on chromo- some 17 and promyelocytic leukemia (PML) gene on chromosome 15 is the hallmark for acute promyelocytic leukemia (APL). Three different PML/RARα isoforms have been described; S-form, L-form and V-form. Our aims were to characterize the different types of PML/RARα iso- forms in Malay patients with APL and to determine the outcome of these different types of iso- forms. Materials and methods: RT-PCR analysis was performed on 20 patients recruited from hematology-oncology ward. RT-PCR detected fusion transcript of PML/RARα in all patients. Results and Discussion: Of these patients, 65% (13 patients) exhibited L/V-form, and 35% (7 patients) S-form. Total white blood cell count (TWBC) was higher in L/V-form (25 x 109/l) compared to S-form (2.1 x 109/l) (p < 0.05). Five years survival rate was 100% and 33.3% for L/V-forms and S-forms respectively (p<0.005). Conclusion: We conclude that L/V- forms is the commonest isoform among Malays. They presented at younger age with higher TWBC counts. Although the sample size is small, our preliminary data showed an interestingly longer survival outcome among L/V-forms compared to S-form. PML/RARα isoforms could be used in future as risk stratification feature in patients diagnosed as APL. Further study with more number of patients is required.

Management of patients with hematological malignancies undergoing coronary artery bypass grafting.

The number of patients with a previously diagnosed malignancy who need cardiac surgery is increasing. Patients with hematological malignancies represent only 0.38% of all patients undergoing cardiac surgery. The literature in this subset of patients is limited to only a few retrospective case series, with limited number of patients undergoing emergency cardiac surgery. We describe three cases with hematological malignancies namely chronic myelogenous leukemia, acute promyelocytic leukemia and chronic lymphocytic leukemia presenting for coronary artery bypass grafting (CABG). Two patients were taken up for emergency CABG in view of ongoing ischemia, one of them was on preoperative intra-aortic balloon pump support. No mortality was observed. Two patients needed transfusion of blood products which was guided by thromboelastography. One patient developed superficial sternal wound infection requiring antibiotic therapy.