Centre for Colorectal Disease, St Vincent's University Hospital, Elm Park, Merrion Rd, Dublin 4, Ireland.
Department of Medical Oncology, St Vincent's University Hospital, Elm Park, Merrion Rd, Dublin 4, Ireland.
Fam Cancer. 2024 Nov 15;24(1):2. doi: 10.1007/s10689-024-00427-7.
Colorectal cancer (CRC) is a common cancer in Ireland. Of all CRCs, 2-4% are attributable to Lynch Syndrome (LS), the most common CRC predisposition syndrome. LS is caused by constitutional pathogenic variants (PVs) affecting mismatch repair (MMR) genes with resultant MMR protein deficiency (dMMR). Screening of all CRCs with MMR immunohistochemistry (IHC) testing is advocated to increase the detection of LS. However, successful implementation requires appropriate downstream management. In Ireland the traditional pathway involves referral to cancer genetics services to assess eligibility for genetic testing. Cancer genetics services in Ireland face many challenges in providing uniform access to timely healthcare with current wait times for assessment in excess of 1 year. An increasingly adopted pathway is that of mainstreaming, whereby genetic testing is managed locally by a multidisciplinary team member. Our institution therefore implemented an Advanced Nurse Practitioner (ANP)-led service with responsibility for the LS Diagnostic Pathway and mainstream genetic testing. Data was extracted from a prospectively maintained database of all newly diagnosed CRC patients discussed at our institutions CRC multidisciplinary meeting (MDM) between January 1st, 2023, and May 31st, 2024. MMR IHC testing was performed in 97.9% of the 385 patients diagnosed with CRC. The median time from histological confirmation of CRC to the availability of the MMR IHC report was 6 days. All 51 patients (100%) who required sequential tumor testing underwent BRAF V600 ± MLH1 promoter methylation testing. Additionally, 100% of the 14 patients eligible for mainstream genetic testing were referred to the ANP-led genetics service. The median time from the initial MDM discussion to the initiation of genetic testing was 69 days, while the median time from testing to the availability of results was 19 days. Patients received their results within a median of 21 days. MMR IHC testing increases the detection of LS through identification of dMMR tumours. Successful downstream delivery of clinical services, however, requires appropriate subsequent management, in a resource-limited environment. Our institutional experience demonstrates the feasibility, efficiency, and effectiveness of an ANP-led mainstreaming model of care for hereditary colorectal cancer.
结直肠癌（CRC）是爱尔兰常见的癌症。在所有 CRC 中，有 2-4%归因于林奇综合征（LS），这是最常见的 CRC 易患综合征。LS 是由影响错配修复（MMR）基因的致病变异（PV）引起的，导致 MMR 蛋白缺乏（dMMR）。提倡对所有 CRC 进行 MMR 免疫组织化学（IHC）检测筛查，以增加 LS 的检出率。然而，成功实施需要适当的下游管理。在爱尔兰，传统途径是将其转介至癌症遗传学服务机构，以评估是否有资格进行基因检测。爱尔兰的癌症遗传学服务机构在提供及时的医疗保健方面面临许多挑战，目前评估的等待时间超过 1 年。越来越多的途径是主流化，即由多学科团队成员管理遗传检测。因此，我们机构实施了由高级执业护士（ANP）领导的服务，负责 LS 诊断途径和主流遗传检测。数据从我们机构 CRC 多学科会议（MDM）讨论的所有新诊断 CRC 患者的前瞻性维护数据库中提取，时间范围为 2023 年 1 月 1 日至 2024 年 5 月 31 日。在诊断为 CRC 的 385 名患者中，有 97.9%进行了 MMR IHC 检测。从组织学确认 CRC 到获得 MMR IHC 报告的中位时间为 6 天。所有需要进行后续肿瘤检测的 51 名患者（100%）均进行了 BRAF V600±MLH1 启动子甲基化检测。此外，有 14 名符合主流基因检测条件的患者（100%）均被转介至由 ANP 领导的遗传学服务机构。从最初的 MDM 讨论到开始基因检测的中位时间为 69 天，而从检测到获得结果的中位时间为 19 天。患者在中位时间 21 天内收到了检测结果。MMR IHC 检测通过识别 dMMR 肿瘤增加了 LS 的检出率。然而，在资源有限的环境中，成功提供临床服务的下游交付需要适当的后续管理。我们机构的经验证明了由 ANP 领导的遗传性结直肠癌主流化护理模式的可行性、效率和有效性。
