Department of Pathology, Hallym University Kangnam Sacred Heart Hospital, Seoul, Korea.
Department of Pathology, Seoul National University Bundang Hospital, Seongnam, Korea.
J Gynecol Oncol. 2022 Mar;33(2):e15. doi: 10.3802/jgo.2022.33.e15. Epub 2021 Dec 6.
We evaluated droplet digital polymerase chain reaction (ddPCR) method for detecting mutations in endometrial cancer (EC) and guiding its molecular classification.
We reviewed 240 EC specimens from our hospital database. A ddPCR assay was used to identify mutations at 5 known hotspots (P286R, S297F, V411L, A456P, and S459F). Expressions of p53 and mismatch repair proteins were identified using immunohistochemistry.
The ddPCR assay identified mutations in 10.8% of patients. The most common mutation was V411L (61.54%), followed by P286R (23.07%), S459F (7.69%), S297F (3.85%), and A456P (3.85%). Eight/one cases had positive ddPCR but negative Sanger sequencing/next-generation sequencing, respectively. Molecular classification revealed -mutated subtype as significantly more common for tumors with a high International Federation of Gynecology and Obstetrics (FIGO) grade, deep myometrial invasion, lymphovascular space invasion, advanced stage, and high/advanced risk groups; the mutated group was more frequent in the low stage and low/intermediate risk group. Survival analyses revealed the poorest outcomes for -mutated EC, while mismatch repair-deficient and no specific molecular profile ECs had similar progression-free survival (PFS) outcomes, and -mutated ECs had the best PFS outcome (p<0.001). When only intermediate, high-intermediate, and high-risk groups were analyzed for subgroups, molecular classification still showed differences both in PFS (p=0.003) and overall survival (p=0.017).
Hotspot mutations can be detected using the ddPCR assay. We suggest simultaneously evaluating mutation status using ddPCR and p53/mismatch repair protein expressions using immunohistochemistry, which can rapidly and accurately determine the molecular subtype of EC.
评估液滴数字聚合酶链反应（ddPCR）方法检测子宫内膜癌（EC）突变并指导其分子分类。
我们回顾了我院数据库中 240 例 EC 标本。使用 ddPCR 检测鉴定 5 个已知热点（P286R、S297F、V411L、A456P 和 S459F）的突变。使用免疫组织化学法鉴定 p53 和错配修复蛋白的表达。
ddPCR 检测鉴定出 10.8%的患者存在突变。最常见的突变是 V411L（61.54%），其次是 P286R（23.07%）、S459F（7.69%）、S297F（3.85%）和 A456P（3.85%）。分别有 8/1 例的 ddPCR 阳性而 Sanger 测序/下一代测序阴性。分子分类显示 -突变亚型在国际妇产科联合会（FIGO）分级高、肌层浸润深、脉管侵犯、晚期和高危/高级别组的肿瘤中更为常见；而 突变组在低分期和低/中危组中更为常见。生存分析显示 -突变 EC 的预后最差，而错配修复缺陷和无特定分子谱 EC 的无进展生存期（PFS）相似，而 -突变 EC 的 PFS 最佳（p<0.001）。当仅对中危、中高危和高危组进行亚组分析时，分子分类在 PFS（p=0.003）和总生存期（p=0.017）方面仍存在差异。
ddPCR 检测可检测热点突变。我们建议同时使用 ddPCR 评估 突变状态，并使用免疫组织化学法评估 p53/错配修复蛋白表达，这可以快速准确地确定 EC 的分子亚型。
