Background: Acute leukemia is classified as lymphoid or myeloid depends on antigen expression. Knowledge about acute biphenotopic leukemia (BAL) is limited; both in terms of clinical and biological presentation and also in regard to treatment outcome. Hereby we are completing the work done by our group which looked at the laboratory features of BAL by reviewing the clinical presentation and response to different chemotherapy protocols used at our institute for treatment of patients with BAL to estimate over all survival.

Methods: Out of 478 adult patients with acute leukemia, we analyzed 15(3.1%) cases classified as BAL according to EGIL score system. Clinical data were collected retrospectively and analyzed. Five different chemotherapy protocols had been used. Six(40%) patients had received VCEPM (Vincristine 1.4mg/m2 x 4 doses, Cyclophosphamide 600mg/ m2 , Etoposide 100mg m2 daily for 5 doses, Prednisone 60mg/m2 for28 days). Four (27%)cases had received 1423 KFSH protocol (Cyclophosphamide 1200mg/m 2 x 1 dose, Daunorubicin 45mg/m2 for 3 doses, Vincristine 1.4mg/m2 once every week x 4 doses, Prednisone 60mg/m2 for 21 days, L-Asparaginase 6000 iu/m 2 every 3 days x 6 doses). Standard ICE protocol was used for induction in 3 cases and in 2 patients modified St Jude protocol (Vincristine 1.5mg/m 2 once every week x 4 doses, Daunomycin 25mg/m2 once every week x 2 doses, Prednisone 40mg/m 2 daily for 25 dose, L-Asparaginase 10000u/m 2 every 3 days for 6 doses, Etoposide 300mg/m 2 every 4 days x 3 doses and Cytarapin 300mg/m 2 every 4 days x 3 doses).

Results: We had 11 males and 4 females with mean WBC count on presentation of 74.7 x 109/L.Chromosomal karyotype was done for all except one, 4(29%) were normal and 8(53%) had complex karyotype Of all patients with BAL leukemia, 4(27%), 8(53%) and 10(67%) had hepatomegaly,splenomegaly and lymphadenopathy respectively. Initial evaluation done on D14 post chemotherapy revealed evidence of residual leukemia (> 5% blasts) in 1 out of 6 patients treated with VCEPM and 7 out of the other 9 patients received different other protocols. Out of the eight patients with residual leukemia, 4 had received salvage chemotherapy with FA (Fludarabine 30mg/ m2, Cytarabine2mg/ m2 x 5doses) and 2 had received MEC (Mitoxantrone 6mg/ m2 , Etopside 80mg/ m2, Cytarabine1mg/ m 2 x 6 doses) and one received modified St Jude while one underwent for SCT. ALL except one had achieved CR. Total of 10(66%) underwent SCT in CR. Although there were 9 (60%) died during the follow up, the OS at two years was (50%).

Conclusion: Adult BAL is an aggressive disease that is associated with complex karyotype with poor response to single lineage treatment. The use of hybrid drugs (VCEPM like) that are effective for lymphoid and myeloid leukemia improve the respond.

Author notes

Disclosure: No relevant conflicts of interest to declare.