Comparative genomic hybridization and amplotyping by arbitrarily primed PCR in stage A B-CLL

Cytogenetic analysis is useful in the diagnosis and to assess prognosis of B-cell chronic lymphocytic leukemia (B-CLL). However, successful cytogeneti cs by standard techniques has been hindered by the low in vitro mitotic act ivity of the malignant B-cell population. Fluorescence in situ hybridizatio n (FISH) has become a useful tool, but it does not provide an overall view of the aberrations. To overcome this hurdle, two DNA-based techniques have been tested in the present study: comparative genomic hybridization (CGH) a nd amplotyping by arbitrarily primed PCR (AP-PCR). Comparative genomic hybr idization resolution depends upon the 400-bands of the human standard karyo type. AP-PCR allows detection of allelic losses and gains in tumor cells by PCR fingerprinting, thus its resolution is at the molecular level. Both te chniques were performed in 23 patients with stage A B-CLL at diagnosis. The results were compared with FISH. The sensitivity of AP-PCR was greater tha n CGH (62% vs 43%). The use of CGH combined with AP-PCR allowed to detect g enetic abnormalities in 79% (15/19) of patients in whom G-banding wa,, not informative. providing a global view of the aberrations in a sole experimen t. This study shows that combining these two methods with FISH, makes possi ble a more precise genetic characterization of patients with B-CLL. (C) 200 1 Elsevier Science Inc. All rights reserved.