Despite all effort and use of more effective treatment protocols, chronic lymphocytic leukemia remains an incurable disease (the only potentially curative method is allogeneic hematopoietic stem cell transplantation). Although complete clinical remission is reached in many patients following treatment, conventional chemotherapy rarely leads to the decrease of tumor cell burden bellow the limits of sensitivity of modern methods, i.e. to minimal residual disease negativity.
The persistence of residual tumor cells, undetectable by standard techniques (cytology, histology, conventional flow cytometry), underlies the relapses of the disease. The use of new treatment strategies - application of monoclonal antibodies, chemoimmunotherapy, hematopoetic stem cell transplants - made it possible to improve the treatment response in terms of diminishing the number of tumor cells detectable by modern methods with high sensitivity.
Current knowledge suggests that minimal residual disease negativity might confer better prognosis and eradication of minimal residual disease is becoming the end-point of clinical studies. The paper summarizes the current view on the assessment of minimal residual disease in chronic lymfocytic leukemia and its possible use in daily clinical practice.