Aberrant T-cell antigen expression in B lymphoblastic leukaemia

作者：Hussein Shafinaz; Gill Kamraan Z; Sireci Anthony N; Colovai Adriana I; Small Tania; Emmons Foxwell N; Murty Vundavalli V; Bhagat Govind; Alobeid Bachir^*

来源：British Journal of Haematology, 2011, 155(4): 449-456.

DOI：10.1111/j.1365-2141.2011.08870.x

• B lymphoblastic leukaemia
• acute lymphoblastic leukaemia
• T-cell antigen
• NK cell antigen

B lymphoblastic leukaemia (B-ALL) cells are characterized by the expression of various B-cell antigens. Expression of T/Natural Killer-cell antigens, however, has rarely been reported in B-ALL (TAg+ B-ALL), and the significance of this aberrant antigen expression is unclear. We thus analysed the frequency of TAg+ B-ALL at our institution and investigated its significance in the context of immunophenotypes, cytogenetic/molecular findings, and prognosis. We reviewed 134 consecutive cases of B-ALL and found 18 cases (13.4%) of TAg+ B-ALL. The most common aberrant T-cell antigens expressed were CD2, CD5, and CD7 at equivalent rates (each in six cases), CD4 (two cases), and CD56 (three cases). Adverse cytogenetic abnormalities were seen in a significantly larger proportion of the TAg+ cases (72.2%) than the TAg- cases (32.2%; P = 0 003). Multivariate Cox-regression analysis showed that the risk of relapse over time was higher in the TAg+ cases, independent of high risk status (based on age and white blood cell count) and the presence of adverse cytogenetic abnormalities (hazard ratio = 2 256, P = 0 065). These findings suggest that T-cell antigen expression in B-ALL may be an independent predictor of poor prognosis, and a useful marker to identify patients at increased risk for relapse and for harbouring adverse cytogenetic abnormalities.

• 出版日期2011-11