Division of Gastroenterology, Tulane University School of Medicine, New Orleans, Louisiana, USA.
Louisiana Tumor Registry, Epidemiology Program, LSU Health Sciences Center School of Public Health, New Orleans, Louisiana, USA.
Am J Gastroenterol. 2015 Jul;110(7):948-55. doi: 10.1038/ajg.2014.417. Epub 2015 Jan 20.
As there are no US population-based studies examining Lynch syndrome (LS) screening frequency by microsatellite instability (MSI) and immunohistochemistry (IHC), we seek to quantitate statewide rates in patients aged ≤50 years using data from a Centers for Disease Control and Prevention-funded Comparative Effectiveness Research (CER) project and identify factors associated with testing. Screening rates in this young, high-risk population may provide a best-case scenario as older patients, potentially deemed lower risk, may undergo testing less frequently. We also seek to determine how frequently MSI/IHC results are available preoperatively, as this may assist with decisions regarding colonic resection extent.
Data from all Louisiana colorectal cancer (CRC) patients aged ≤50 years diagnosed in 2011 were obtained from the Louisiana Tumor Registry CER project. Registry researchers and physicians analyzed data, including pathology and MSI/IHC.
Of the 2,427 statewide all-age CRC patients, there were 274 patients aged ≤50 years, representing health care at 61 distinct facilities. MSI and/or IHC were performed in 23.0% of patients. Testing-associated factors included CRC family history (P<0.0045), urban location (P<0.0370), and care at comprehensive cancer centers (P<0.0020) but not synchronous/metachronous CRC or MSI-like histology. Public hospital screening was disproportionately low (P<0.0217). Of those tested, MSI and/or IHC was abnormal in 21.7%. Of those with abnormal IHC, staining patterns were consistent with LS in 87.5%. MSI/IHC results were available preoperatively in 16.9% of cases.
Despite frequently abnormal MSI/IHC results, LS screening in young, high-risk patients is low. Provider education and disparities in access to specialized services, particularly in underserved populations, are possible contributors. MSI/IHC results are infrequently available preoperatively.
由于美国没有基于人群的研究，通过微卫星不稳定性（MSI）和免疫组织化学（IHC）来检查林奇综合征（LS）的筛查频率，因此我们试图使用疾病控制与预防中心（CDC）资助的一项比较有效性研究（CER）项目的数据，量化全州范围内≤50 岁患者的筛查率，并确定与检测相关的因素。在这个年轻的高危人群中，筛查率可能提供了最佳情况，因为年龄较大的患者，可能被认为风险较低，可能接受的检测频率较低。我们还试图确定 MSI/IHC 结果在术前获得的频率，因为这可能有助于确定结肠切除范围的决策。
从路易斯安那州肿瘤登记处 CER 项目中获取了所有 2011 年诊断为≤50 岁的路易斯安那州结直肠癌（CRC）患者的数据。登记研究人员和医生分析了数据，包括病理学和 MSI/IHC。
在全州所有年龄的 2427 例 CRC 患者中，有 274 例≤50 岁，代表了 61 个不同医疗机构的医疗保健。23.0%的患者进行了 MSI 和/或 IHC 检测。检测相关因素包括 CRC 家族史（P<0.0045）、城市位置（P<0.0370）和综合癌症中心的治疗（P<0.0020），但不包括同步/异时性 CRC 或 MSI 样组织学。公立医院的筛查比例过低（P<0.0217）。在接受检测的患者中，MSI 和/或 IHC 异常率为 21.7%。在 IHC 异常的患者中，染色模式与 LS 一致的比例为 87.5%。16.9%的病例术前获得了 MSI/IHC 结果。
尽管 MSI/IHC 结果经常异常，但年轻高危患者的 LS 筛查率较低。提供者教育和获得专门服务的机会存在差异，特别是在服务不足的人群中，这可能是导致这种情况的原因。MSI/IHC 结果术前很少获得。
