Correlation between the proportion of Philadelphia chromosome-positive metaphase cells and levels of BCR-ABL mRNA in chronic myeloid leukaemia

✍ Scribed by Feng Lin; Andrew Chase; Julie Bungey; John M. Goldman; Dr. Nicholas C. P. Cross

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 404 KB
• Volume: 13
• Category: Article
• ISSN: 1045-2257
• DOI: 10.1002/gcc.2870130207

✦ Synopsis

Abstract

We have sought to define the relationship between the proportion of marrow metaphases showing the Philadelphia chromosome (Ph) and levels of BCR‐ABL mRNA assessed by quantitative polymerase chain reaction (PCR) in patients with chronic myeloid leukaemia (CML). From a total of 141 patients, 164 PCR assays were performed on peripheral blood samples taken within 2 weeks of a bone marrow specimen analysed by cytogenetics. BCR‐ABL mRNA was quantified in all 106 PCR‐positive samples by competitive PCR; results ranged from < 10 to 3.4 × 10^6^ transcripts/μg RNA. Twenty‐one chronic‐phase patients had a median of 5.0 × 10^5^ BCR‐ABL transcripts/μg RNA; no difference in levels of the fusion mRNA was found between 15 Ph‐positive and six Ph‐negative, BCR‐ABL‐positive patients. Ph‐positive metaphases were not detected in any individual who was PCR negative (n = 58) and in only a single patient who was PCR positive with < 10^3^ BCR‐ABL transcripts/μg RNA (n = 44). Conversely, of 41 samples from patients in haematological remission who had >10^3^ BCR‐ABL transcripts/μg RNA, 30 had at least one Ph‐positive metaphase. The highest level of BCR‐ABL transcripts at which Ph‐positive metaphases were not detected was 1.5 × 10^4^. For the 46 patients who had at least one Ph‐positive metaphase, a good correlation (Spearman coefficient = 0.83, P <0.0001) was found between the percentage of Ph‐positive metaphases and BCR‐ABL transcript levels. We conclude that quantitative PCR for BCR‐ABL is an effective method for monitoring CML patients after bone marrow transplantation and is less invasive than conventional cytogenetic studies of bone marrow. © 1995 Wiley‐Liss, Inc.