Report of the Korean Association of External Quality Assessment Service on Next-Generation Sequencing Analysis for Somatic Variants (2018–2020)

초록

Next-generation sequencing is widely used to detect a variety of genetic defects in many disorders. The detection of somatic variants in patients with cancer, including hematologic malignancy, is important for diagnosis, treatment, and prognosis. However, due to the complicated process, accurate and reliable detection of somatic variants by next-generation sequencing remains challenging. We investigated the proficiency tests conducted by the Korean Association of External Quality Assessment Service from 2018 to 2020 and their effects on the analytical performance of clinical laboratories. During the 3-year study period, six rounds of proficiency tests were conducted. In each round, the participating laboratories were required to report Tier I/ II somatic variants detected from electronic data and a DNA specimen. The analytical performance was evaluated by calculating the acceptance rate for each genomic position investigated. The possible causes of ‘nonevaluable’ and ‘unacceptable’ variants were also explored. Among the six rounds of proficiency tests, the acceptance rates for all tested variants were above 80% and acceptance rates of 100% were identified in more than half of the variants in the target regions. Issues of variant classification and falsenegative variants were addressed through the analysis of ‘non-evaluable’ variants. The significant causes of ‘unacceptable’ variants were identified as wrong protein or nucleotide numbering. In conclusion, the proficiency tests demonstrated the good analytical performance of the participating clinical laboratories. Although the findings identified some problems awaiting solutions, the proficiency tests may help clinical laboratories to improve their performance in detecting somatic variants by next-generation sequencing.

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