Pretreatment cytogenetic abnormalities as a prognostic factor in adult acute lymphoblastic leukemia

Introduction: Acute lymphoblastic leukemia (ALL) is a malignant proliferation of lymphoid cells blocked at an early stage of differentiation. Prognostic features such as age, WBCs, immunophenotyping, cytogenetic and molecular aberrations significantly influence response to therapy and survival. So far, the karyotype of the ALL blasts is the most important independent prognostic factor.Objective: This study aimed to assess the influence of pre-treatment cytogenetic abnormalities as a predictive of induction success and thier impact on disease free survival and overall survival of adult ALL.Subject and methods: Thirty adult patients with acute lymphoblastic leukemia were included in our study with median age of 25 years (range from 15-61), 17 patients (56.6%) were male and 13 patients (43.4%) were females with male to female ratio 1.3:1, the mean WBC count was 36.56±38.22 x 103/μL ranging from 1.5 x 103/ μL to 150 x 103/ μL. All patients were subjected to complete medical history, thorough physical examination, routine laboratory investigations and cytogenetic analysis using G banding technique.They were classified according to their cytogenetic abnormalities into one of the two groups, the favorable group includes 19 patients (63.33%) and the unfavorable include 11 patients (36.66%) .All patients were treated with ALL protocol and response were evaluated after 2 and 4 weeks from the beginning of induction phase with follow up for 1 year.Result: Complete response (CR) was observed in 23 patient (76.66%), no response was observed in 7 patients (23.78%).18 patients (94.7%) out of 19 patients with favorable cytogenetic abnormalities achieved CR.5 patient (45%) out of 11 patients with unfavorable cytogenetic abnormalities achieved CR.There was statistically significant association between response and cytogenetics.Disease free survival (DFS) of the whole group at 1 year was (70%), while overall survival (OS) was (55%).Both DFS rate and OS rate were significantly affected by immunophenotyping, cytogenetics and time to achieve CR.Conclusion and Recommendations:- Pretreatment cytogenetic abnormalities are the most important independent prognostic factor which significantly influence response to induction therapy and survival in adult patients with acute lymphoblastic leukemia.Both DFS rate and OS rate were significantly affected by immunophenotyping, cytogenetics and time to achieve CR.Further studies on a larger number of patients, with a long follow-up, using more advanced techniques are recommended to:Evaluate different cytogenetic abnormalities and their molecular bases which contribute to understand the pathogenesis and prognosis of ALL.And to help in prediction of the response to standard induction, choosing the post remission therapy and finding new target therapies.