ABSTRACT

Aim: To determine the frequency and evaluate the expression of CD79a and PAX5 in precursor B lymphoblastic leukemia.

Study design: Cross sectional study

Setting of study and duration: Lahore General Hospital and Chughtai’s Lahore lab. and the study duration was one year i.e., from 11st July 2015 to 31st June 2016.

Methods: A total of 56 cases were included in the studyafter fulfilling the inclusion criteria. Suitable cases were identified by as per our selection criteria. Paraffin embedded trephine blocks were provided for immunohistochemistry by the Haematology Department of Lahore general hospital, and Chugtai’s Lahore lab. Immunohistochemistry was done for PAX5 and CD79a and results were noted. Data entry and analysis was done by using SPSS 20. Quantitative variables were presented by using mean±SD. Qualitative variables were presented by using Frequency table and percentages.

Results: Median age was 6. Mean age at presentation was 6.78 year. Out of 56 cases 31(55.36%) were males and 25(44.64%) were female.Mean age of male patients was 6.51±3.02 ranging from 2 and 13 years. Mean age of female patients was 7.12±3.64 years ranging from 2 and 14 years. A total of 56 cases were studied. Out of these 49(87.5%) were found positive for CD79a. Twelve point five percent (n=7) showed negative results. The expression of CD79a was cytoplasmic. Sensitivity of CD79a is calculated to be 87.5%. While positive predictive value and diagnostic accuracy is 100% and 87.5% respectively.

Conclusion: It is concluded that PAX5 may prove to be a better diagnostic marker in the evaluation of B cell acute lymphoblastic leukemia cases. Therefore it should be included in antibody panel along with routinely used pan B cell markers such as CD19, CD20 and CD79a. PAX5 showed positivity even in those cases which were negative for CD79a and it gave better sensitivity than CD79a. Therefore, the addition of PAX5 in the antibody panel along with other pan B cell markers can lead to more accurate diagnosis.

Keywords: PAX5 ,CD79a, B lymphoblastic leukemia