Year: 2005
Type: article
Abstract: The most important factor to consider in planning initial treatment for a patient with relapsed or refractory AML is the length of the first CR. For practical purpose, patients can be divided into those with first CRs /1 year and those with shorter first CRs (or no first CR, i.e. primary refractory). Three types of therapies are available: allogeneic transplant (allotrans), high-dose ara-C-containing regimens (HDAC), and regimens including various drugs other than ara-C and an anthracycline (non a-a). Comparison of M.D. Anderson data (chemotherapy) with IBMTR data (transplant) suggest that the best option is an allotrans, particularly if the patient had a short or no first CR; however, the degree to which the data are influenced by selection bias is unknown. If an allotrans is not feasible, patients with longer 1st CRs should receive HDAC-containing therapy. Our data suggest that such therapy not only produces higher CR rates, but, more importantly, improves survival relative to non a-a regimens; obviously this conclusion could change were a very successful new non a-a regimen to appear. In contrast, the data indicate that, although HDAC also produces higher CR rates than non a-a in patients with shorter first CRs, or who are primary refractory, this higher CR rate is not associated with a survival advantage, probably because the achieved CRs are very brief and because of higher early death rates with HDAC. As a result, such patients are ideal for investigation of new non a-a regimens. The same is true for virtually all second salvage patients (patients who have received initial induction therapy /1 additional therapy to produce a CR). At any time several new non a-a regimens are under investigation at M.D. Anderson. Currently, these include a new anti-fol, new histone acetylase inhibitors, a combination of the latter with decitabine, and other drugs whose mechanism of action is unclear, although they are active in, admittedly very imperfect, model systems. A problem with evaluation of these agents has been a focus on assessing the activity of a given regimen, rather than on assessing whether that regimen is more active than another regimen; this latter question is of more interest to patients. To address this problem it might be a good idea to randomize patients among various protocols, and methods for doing this will be discussed.
Source: Hematology
Author: E. Estey
Institution: The University of Texas MD Anderson Cancer Center
Language: English
Subfield: Hematology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W1990815020