Although the gold standard for TMB determination is whole-exome sequencing (WES), focused panels, like the Oncopanel All-In-One v2.0, have been evaluated extensively for TMB estimation because of their lower sequencing cost and higher sensitivity. Recent research shows, that panels with a size > 1.5 Mbp are sufficiently suited to determine TMB with a high concordance to WES (Buchhalter et al. 2019, Int J Cancer 144:848–858). Thus, Oncopanel All-In-One 2.0’s size of 3 Mbp provides more precise TMB estimates than other smaller panels.