الفهرس 
coverEnglishOnly 14 pages are availabe for public view
 |  | from | 210 |  |  |
| | | from | 210 | | |
Abstract
We investigated whether detection of minimal residual. disease MRD) in peripheral blood stem cells (PBSC) by using tyrosine ydroxylase (TH) expression could predict outcome of patients withadvanced neuroblastoma.<Patients and methods: Quantitative real time polymerase chain reaction<was performed for the detection of tumor contamination using TH<messenger ribonucleic acid (mRNA) and correlated to clinical parameters<and outcome in 20 high-risk neuroblastoma patients, while another 20<patients had unknown expression of TH.<Results: We studied a total of 20 samples of high risk neuroblastoma<patients for TH and GAPDH expression. All cases were negative for TH<expression and positive for GAPDH ensuring good quality and quantity<of the tested cDNA. The 24-month overall survival (OS) for the whole<group of patients was 64.7%, while the 12-month disease-free survival<(DFS) was 55.5%. We did not find any significant correlation between<different prognostic factors (age, stage, MYCN amplification,<resectability, status before HSCT, radiation therapy) and TH mRNA<expression except for the viability of PBSCs (p-value of 0.008). Marginal<significance was found in OS among patients with negative TH (57.2%)as compared to patients in whom MRD by TH was not done (70%) with P<0.104. However, there was no statistical significance in DFS amongboth groups (P = 0.384).<Conclusion: Our results obtained in a small cohort of homogeneously<treated high-risk patients suggest that all 20 cases were negative for TH<expression. This indicates a need to increase sample size in a long-term<clinical outcome study to clarify the importance of TH mRNA<contamination in PBSC.<Keywords: neuroblastoma, minimal residual disease, peripheral blood.