Current guidelines for patients with chronic lymphocytic leukemia (CLL) recommend mutation status determination of the clonotypic IGHV gene before treatment initiation to guide the choice of first-line therapy. Currently, commercially available next-generation sequencing (NGS) solutions have technical constraints, as they necessitate at least a 2 × 300 bp sequencing, which restricts their use for routine practice. The cost of the commercial kits also represents an important drawback. We present a new method called Next-CLL, a ready-to-use strategy to evaluate IGHV gene mutation status using any NGS device (including 2 × 150 bp sequencers) in routine diagnostic laboratories. The performance of Next-CLL was validated on genomic DNA and cDNA obtained from 80 patients with CLL at diagnosis. Next-CLL identified a productive clone in 100% of cases, whereas PCR with Sanger sequencing led to a 12.5% failure rate. Next-CLL had 100% concordance with the reference technique for IGHV gene identification and allowed assessment of the IGHV mutation status from the leader sequence, following international guidelines. Comparing a large retrospective series of samples, analyzed by using Sanger sequencing (n = 773) or Next-CLL (n = 352), showed no bias in IGHV usage or mutational status, further validating our strategy in the real-life setting. Next-CLL represents a straightforward workflow for IGHV analysis in routine practice to assess clonal architecture and prognosis of patients with CLL.
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