同源重组缺陷 (HRD) 测试用于确定聚 ADP-核糖聚合酶抑制剂对上皮性卵巢癌且无种系/体细胞 BRCA1/2 改变的患者的适用性。 Myriad MyChoice CDx 报告基因组不稳定性评分 (GIS)，以量化 HRD 水平，阳性评分定义为 ≥42。作者试图定义与获得不确定的 HRD 测试结果相关的因素。GIS 是在其机构中检索的 2020 年 4 月至 2023 年 8 月期间接受 HRD 测试、无种系/体细胞 BRCA1/2 有害改变的上皮性卵巢癌患者。临床数据为从医疗记录中提取。在确定的 477 份 HRD 测试结果中，57 份 (12%) 没有结论。高级别浆液性卵巢癌的 GIS 高于其他组织学类型（中位数 29 比 21，p < .001）。大多数 HRD 病例的组织学级别为高级别浆液性；没有透明细胞或子宫内膜样组织学病例 HRD 阳性。在单变量分析中，间隔时间与初次细胞减灭术、其他标本来源与手术标本以及化疗暴露是不确定 HRD 测试的危险因素。在多变量分析中，化疗暴露和组织来源与不确定的测试结果相关，手术标本比其他来源（活检、细胞学等）更有可能产生结论性结果。年龄、分期、自我报告的种族和组织学与不确定的结果无关。与其他来源的上皮性卵巢癌组织采集相比，手术组织更有可能产生结论性的 HRD 测试结果。如果可行，在开始新辅助化疗前进行腹腔镜活检可能会增加获得可解释的 HRD 测试结果的可能性。© 2024 美国癌症协会。

Homologous recombination deficiency (HRD) testing is used to determine the appropriateness of poly ADP-ribose polymerase inhibitors for patients with epithelial ovarian cancer and no germline/somatic BRCA1/2 alterations. Myriad MyChoice CDx reports a genomic instability score (GIS) to quantify the level of HRD, with a positive score defined as ≥42. The authors sought to define factors associated with obtaining an inconclusive HRD test result.GIS was retrieved for patients at their institution with epithelial ovarian cancer without germline/somatic BRCA1/2 deleterious alterations who underwent HRD testing from April 2020-August 2023. Clinical data were abstracted from the medical record.Of 477 HRD test results identified, 57 (12%) were inconclusive. High-grade serous ovarian cancers had higher GIS than other histologic types (median 29 vs. 21, p < .001). Most HRD cases were of high-grade serous histology; no cases with clear cell or endometrioid histology were HRD-positive. On univariate analysis, interval versus primary cytoreductive surgery, other specimen sources versus surgical specimens, and chemotherapy exposure were risk factors for inconclusive HRD testing. On multivariable analysis, chemotherapy exposure, and tissue source were associated with an inconclusive test result, with surgical specimens more likely to yield a conclusive result than other sources (biopsy, cytology, other). Age, stage, self-reported race, and histology were not associated with an inconclusive result.Surgical tissue was more likely to yield a conclusive HRD test result versus other sources of epithelial ovarian cancer tissue acquisition. When feasible, laparoscopic biopsy before initiation of neoadjuvant chemotherapy may increase the likelihood of obtaining interpretable HRD test results.© 2024 American Cancer Society.