Evaluating response to treatment of chronic lymphocytic leukemia
- Kanti R Rai, MD
Kanti R Rai, MD
- Professor of Medicine and Molecular Medicine
- Hofstra North Shore-LIJ School of Medicine at Hofstra University
- Stephan Stilgenbauer, MD
Stephan Stilgenbauer, MD
- Professor of Medicine
- Ulm University
Chronic lymphocytic leukemia (CLL) is one of the chronic lymphoproliferative disorders (lymphoid neoplasms) characterized by a progressive accumulation of a usually monoclonal population of functionally incompetent lymphocytes. CLL is considered to be identical (ie, one disease with different manifestations) to the mature (peripheral) B cell neoplasm small lymphocytic lymphoma (SLL). The term CLL is used when the disease manifests primarily in the bone marrow and blood, while the term SLL is used when involvement is primarily nodal (ie, absolute B lymphocyte count in the peripheral blood <5000/microL [5 x 109/L]). (See "Classification of the hematopoietic neoplasms" and "Clinical presentation, pathologic features, diagnosis, and differential diagnosis of chronic lymphocytic leukemia".)
Treatment is indicated when there are disease-related symptoms or evidence of progression (ie, "active disease" (table 1)). Except for allogeneic hematopoietic cell transplantation (HCT), treatment options for CLL are not curative. The International Workshop Group on CLL (IWCLL) published a revised version of the guidelines for evaluating disease response that were published in 1996 by the National Cancer Institute Working Group (NCI/WG) (table 2) [1-3]. These efforts in developing standardized criteria for the evaluation of response have also allowed comparison of results from different therapeutic trials.
The response evaluation and criteria will be reviewed here. The initial treatment of CLL/SLL, the treatment of relapsed or refractory disease, and the management of the complications of CLL are discussed separately. (See "Overview of the treatment of chronic lymphocytic leukemia" and "Treatment of relapsed or refractory chronic lymphocytic leukemia" and "Overview of the complications of chronic lymphocytic leukemia".)
Patients should be evaluated before each treatment cycle to determine how their disease is responding to therapy. The specific evaluation performed to assess the response to therapy differs depending upon whether the patient is enrolled in a therapeutic research protocol (clinical trial) or is being treated in general practice :
●For those treated in general practice, response evaluation should always include a history, physical examination, and complete blood count with differential. The history should include questions regarding constitutional symptoms such as unintentional weight loss, fatigue, fevers, and night sweats. The physical examination should pay particular attention to the evaluation of lymphadenopathy, hepatomegaly, and splenomegaly.
Although bone marrow biopsy with absence of CLL infiltrates on histology is required to confirm a complete remission (CR), it is not always recommended in general practice as it may not impact management. Bone marrow evaluation is indicated in patients with cytopenias of uncertain cause.
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- RESPONSE ASSESSMENT
- RESPONSE CRITERIA
- Response categories
- CR categories
- - Complete remission
- - Complete remission with incomplete bone marrow recovery
- - Minimal residual disease
- PR categories
- - Partial remission
- - Nodal response
- - Nodular partial remission
- Progressive disease
- Stable disease
- RELAPSED DISEASE
- REFRACTORY DISEASE
- INFORMATION FOR PATIENTS