多基因面板测试通过下一代测序（MGP-NGS）能够检测出与特定癌症表型无关的基因中的胚系致病性或可能致病性变异（PVs/LPVs）。基于MGP-NGS的机会性遗传筛查在具有遗传性癌症怀疑的患者中揭示了这些偶然发现（IFs）。根据加泰罗尼亚卫生服务指南，对符合进行遗传检测的临床标准的患者进行了MGP-NGS检测。根据美国医学遗传学和基因组学学院 - 分子病理学协会指南以及英国癌症变异解释小组指南对变异进行了分类。在进行MGP-NGS的817名患者中，发现了10例（1.22%）IFs。患者癌症诊断的平均年龄为49.4±9.5岁。三例IFs（30.0%）在PMS2中检测到，两例（20.0%）在ATM和TP53中检测到，一例（10.0%）在MSH6、NTHL1和VHL中检测到。七例（70.0%）IFs为单核苷酸替换，两例（20.0%）为缺失，一例（10.0%）为复制。三例（30.0%）IF位于内含子区域，三例（30.3%）为无义变异，两例（20.0%）为移码变异，两例（20.0%）为错义变异。六例（60.0%）IF被分类为PVs，四例（40.0%）被分类为LPVs。机会性遗传筛查在我们的队列中提高了1.22%的诊断产量。大多数已鉴定的IFs存在于临床可操作的基因中（n=7，70.0%），为这些家庭提供了加入癌症早期检测计划以及继发性癌症预防的机会。IFs可以有助于对无症状个体的诊断和早期癌症的管理。© 作者（或其雇主）2023。根据CC BY-NC许可进行再使用。不进行商业再使用。由BMJ出版。

Multigene panel testing by next-generation sequencing (MGP-NGS) enables the detection of germline pathogenic or likely pathogenic variants (PVs/LPVs) in genes beyond those associated with a certain cancer phenotype. Opportunistic genetic screening based on MGP-NGS in patients with suspicion of hereditary cancer reveals these incidental findings (IFs).MGP-NGS was performed in patients who fulfilled the clinical criteria to undergo genetic testing according to the Catalan Health Service guidelines. Variants were classified following the American College of Medical Genetics and Genomics-Association for Molecular Pathology guidelines and the Cancer Variant Interpretation Group UK guidelines.IFs were identified in 10 (1.22%) of the 817 patients who underwent MGP-NGS. The mean age at cancer diagnosis was 49.4±9.5 years. Three IFs (30.0%) were detected in PMS2, two (20.0%) in ATM and TP53 and one (10.0%) in MSH6, NTHL1 and VHL. Seven (70.0%) IFs were single-nucleotide substitutions, two (20.0%) were deletions and one (10.0%) was a duplication. Three (30.0) IFs were located in intronic regions, three (30.3%) were nonsense, two (20.0%) were frameshift and two (20.0%) were missense variations. Six (60.0%) IFs were classified as PVs and four (40.0%) as LPVs.Opportunistic genetic screening increased the diagnostic yield by 1.22% in our cohort. Most of the identified IFs were present in clinically actionable genes (n=7; 70.0%), providing these families with an opportunity to join cancer early detection programmes, as well as secondary cancer prevention. IFs might facilitate the diagnosis of asymptomatic individuals and the early management of cancer once it develops.© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.