The clinical and analytical follow-up of patients with MDS depends primarily on their individual prognosis, based on the IPSS scoring system, and the approach chosen for their treatment. Physicians should also consider that the therapy of patients with MDS is always investigational, as no therapy outside of stem cell transplantation is curative. Whenever possible, patients should be included in well-designed clinical trials aimed at evaluating new therapeutic interventions and conducted according to the standards of good clinical practice. In all cases, follow-up evaluations must include serial physical examination; blood analyses, including whole blood counts, and blood biochemistry; and BM aspirates and biopsies. A careful morphologic review of peripheral blood and BM slides is mandatory to evaluate the cellularity, the percentage of blast cells, and the presence and degree of dysplasia of the different hematopoietic cell lines, which may signal the progression to a more advanced morphologic MDS subtype or the occurrence of AML transformation.

Periodic cytogenetic studies are also required to assess the appearance of new chromosomal abnormali-

ties and the evolution of the malignant clone. In addition to conventional cytogenetics, the use of fluorescence in situ hybridization techniques is strongly recommended, because these highly sensitive tests can detect hidden chromosomal aberrations that influence the outcome.63 For this purpose, the use of probes for ruling out numerical and/or structural abnormalities of chromosomes 5, 7, 8, 11 and 20 should be considered. As stated previously, the frequency of invasive techniques should depend on the prognosis, type of therapy, and good clinical judgment. Performing a BM aspirate and biopsy annually seems appropriate for low-risk patients with stable blood cell counts who are not enrolled in a clinical trial. In all instances, a sudden deterioration of cytopenias or the appearance or increase of blasts in the blood should prompt a complete BM evaluation. For patients included in clinical trials, the timing of BM examinations will be determined by the trial specifications. Obviously, in patients undergoing intensive chemotherapy, BM aspirates with or without a core biopsy should be performed after each cycle of treatment. The international consensus criteria for evaluating responses must be strictly adhered to in all cases.

0 0

Post a comment