Response Criteria

The National Cancer Institute-Working Group (NCI-WG) and the International Workshop on Chronic Lymphocytic Leukemia (IWCLL) independently proposed criteria for assessing response in patients with chronic lympho-cytic leukemia (CLL) (Table 25.1), the NCI proposal having gained wider acceptance and being the one usually employed.12

These criteria have proved to be extremely useful to conduct and compare trials, thereby contributing to progress in CLL therapy. Nevertheless, these proposals were elaborated in an era in which no effective therapy for CLL existed. Today, treatment of CLL is based on purine analogs, particularly fludarabine, along with other agents. This results not only in a high complete remission (CR) rate but also in the disappearance, in many instances, of minimal residual disease (MRD)—a situation difficult to envisage when NCI-WG and IWCLL criteria were proposed.

Because of this, classical response criteria are now somewhat obsolete. For example, according to such criteria, patients with less than 30% lymphocytes in a bone marrow aspirate may be classified as complete responders, provided clinical and laboratory findings return to normal. In addition, patients with lymphoid aggregates in bone marrow biopsy are considered to be in nodular partial response, yet these nodules may

Table 25.1

Chronic lymphocytic leukemia: Response criteria

Response

IWCLL criteria

NCI-WG criteria

0 0

Post a comment