Effect of radiologist experience on the risk of false-positive results in breast cancer screening programs.

OBJECTIVES: To evaluate the effect of radiologist experience on the risk of false-positive results in population-based breast cancer screening programmes. METHODS: We evaluated 1,440,384 single-read screening mammograms, corresponding to 471,112 women aged 45-69 years participating in four Spanish programmes between 1990 and 2006. The mammograms were interpreted by 72 radiologists. RESULTS: The overall percentage of false-positive results was 5.85% and that for false-positives resulting in an invasive procedure was 0.38%. Both the risk of false-positives overall and of false-positives leading to an invasive procedure significantly decreased (p < 0.001) with greater reading volume in the previous year: OR 0.77 and OR 0.78, respectively, for a reading volume 500-1,999 mammograms and OR 0.59 and OR 0.60 for a reading volume of >14,999 mammograms with respect to the reference category (<500). The risk of both categories of false-positives was also significantly reduced (p < 0.001) as radiologists' years of experience increased: OR 0.96 and OR 0.84, respectively, for 1 year's experience and OR 0.72 and OR 0.73, respectively, for more than 4 years' experience with regard to the category of <1 year's experience. CONCLUSION: Radiologist experience is a determining factor in the risk of a false-positive result in breast cancer screening.

Advantage of high-resolution melting curve analysis over conformation-sensitive gel electrophoresis for mutational screening of BRCA1 and BRCA2 genes.

BACKGROUND: Mutation screening of BRCA1 and BRCA2 (BRCAs) genes is a time-consuming and costly procedure that demands faster and cheaper alternative methods for routine diagnostics. The present study is aimed at comparing the results obtained with screening mutations methods, conformation sensitive gel electrophoresis (CSGE) and high-resolution melting analysis (HRMA), for BRCAs attending to their specificity, sensitivity, reliability and cost-efficiency. METHODS: We included 52 DNA samples of index patients from high-risk families. The mutational screening was performed by CSGE according to the Ganguly (1993) method and HRMA according to a modified De Leeneer (2008) method. The assays were performed in 384 well plates in the LightCycler 480 (Roche). All PCR products showing altered patterns were confirmed by sequencing. RESULTS: The results obtained with the mutational study of BRCAs genes showed that HRMA exhibited higher sensitivity than CSGE as it was able to detect a wide mutational spectra of genetic variants in a larger number of samples. Aditionally, the combination of HRMA with hybiridization probes in a second step of the assay allows the specific confirmation of mutations. Furthermore, HRMA use less time, allowing the reduction of analysis time. CONCLUSIONS: HRMA offers clear advantages over CSGE for the mutation screening of BRCAs genes as it has greater sensitivity and higher efficiency and it is less time-consuming.