Molecular analysis of PDGFRA and PDGFRB genes by rapid single-strand conformation polymorphism (SSCP) in patients with core-binding factor leukaemias with KIT or FLT3 mutation.

BACKGROUND: Mutations involving KIT and FLT3 genes, encoding tyrosine kinase (TK) membrane receptors, are detected in core-binding factor leukaemia (CBFL) patients. PDFGRA and PDGFRB encode class III TK receptors and are involved both in physiological processes and in the pathogenesis of haematological and solid tumours. The aim of this study was to investigate if PDGFR mutations are involved in CBFL. PATIENTS AND METHODS: In order to detect PDGFR mutations in CBFL, 35 patients without KIT or FLT3 mutations patients were screened by rapid and sensitive single-strand conformation polymorphism (SSCP) analysis. Sequence analysis was performed in polymerase chain reaction (PCR) products showing altered mobility in SSCP analysis in order to determine the nucleotide changes. RESULTS: Three types of single-nucleotide polymorphism (SNP) were detected in the PDGFRA gene (exon 12, exon 13 and exon 18) while no mutation of PDGFRB was detected in the tested CBFLs. CONCLUSION: These data showed that no pathogenic mutations in PDGFRA and PDGFRB were detected in the context of CBFL without KIT and FLT3 mutations. Thus, PDGFR genes do not seem to be involved in CBFL and future studies are needed to establish the genetic causes of the disease in these particular patients.

Prospective monocentric study of non-tunnelled central venous catheter-related complications in hematological patients.

Indwelling central venous catheters (CVCs) are used in the management of hematologic patients. However, insertion and maintenance of CVCs are susceptible to complications. Study design and methods data concerning 388 consecutive catheterisations, performed in oncohematologic patients between April 2003 and December 2004, were prospectively collected. At insertion thrombocytopenia was present in 109 cases (28.1%) and neutropenia in 67 (17.3%). Hemorrhage after CVC insertion occurred in five thrombocytopenic patients (1.3%). The median duration of catheterisation was 18.8 days (range 1-89), longer in the 7-French CVCs utilised in leukemic patients (24.3 days) and shorter in 12-French CVCs (11 days), used for PBSC harvesting. Deep venous thrombosis was diagnosed in 13 cases (3.3%). Ninety-two catheterisations (12.6/1000 days-catheter) were complicated by infections: 19 local infections (4.8%) and 73 (18.8%) bacteraemias of which 45 (11.6%) were catheter-related, mainly due to Gram positive germs (32/45, 71.1%). The frequency of catheter-related bacteraemia was 7.2 events/1000 days-catheter. Thirteen CVCs were removed due to thrombosis, 15 due to infections, 20 due to malfunction, the remaining 333 at patients discharge. At univariate analysis high-dose chemotherapy (p = 0.013), 7-Fr lumen (p = 0.023), acute myeloid leukemia (AML) (p = 0.001), duration of neutropenia >10 days and length of catheterisation were significantly correlated to infection. Multivariate analysis confirmed the duration of catheterisation, AML and high-dose chemotherapy as risk factors. Even though hematological in-patients are at increased risk for bleeding and infections, non-tunnelled CVCs offer a safe venous access also in patients affected by severe thrombocytopenia and prolonged neutropenia.