BCR-ABL transcripts may be detected in essential thrombocythemia but lack clinical significance

HELLER PAULA; KORNBLIHTT LAURA I; CUELLO MARÍA T; LARRIPA IRENE; NAJFELD VESNA; MOLINAS FELISA C

BLOOD, THE JOURNAL OF THE AMERICAN SOCIETY OF HEMATOLOGY - PRINT

The American Society of Hematology

Año: 2001 vol. 98 p. 1990 - 1990

0006-4971

According to criteria established by the Polycythemia Vera Study Group (PVSG), the diagnosis of essential thrombocythemia (ET) relies on exclusion of other myeloproliferative disorders and absence of the Philadelfia (Ph) chromosome and/or the bcr-abl rearrangement. Recently, this issue has been questioned based on the finding of this molecular rearrangement in Ph negative ET patients. However, other studies have failed to confirm these results. We analyzed peripheral blood samples of 48 patients with Ph negative ET for expression of bcr-abl transcripts by reverse transcriptase polymerase chain reaction (RT-PCR). Three cases yielded positive results. Interphase FISH analysis of peripheral blood samples in these three positive patients was negative for the bcr-abl fusion. No differences in clinical and laboratory data were found between patients with positive tests compared with the bcr-abl negative group.  None of them developed features of CML nor disease progression on long term follow-up. On the basis of our results and those of other authors, we conclude that the presence of the bcr-abl rearrangement detected by means of PCR in Ph negative ET patients seems not to exclude the diagnosis of ET.