RRSS Evaluate Completeness Liver Cancer Reporting Under New Clinical Guidelines

肝细胞癌（HCC）是儿童和成人中最常见的原发性肝癌，占所有肝癌的90%。它是全球癌症相关死亡的第三大原因，并且在过去几十年中，HCC的发病率在美国和欧洲一直在上升。在美国，肝癌是亚裔美国人中发病率最高的十大最常见癌症之一。慢性感染B型肝炎病毒（HBV）或丙型肝炎病毒（HCV）是迄今为止肝癌最重要的危险因素。 直到2005年美国肝病研究协会（AASLD）发布了肝细胞癌管理实践指南，美国才出现了HCC诊断、分期和治疗的临床实践指南。该指南建议使用超声、CT扫描和MRI诊断具有典型特征的HCC。如果影像学检查显示出HCC的典型特征，则认为活检是不必要的。只有当影像学上的血管轮廓不是HCC的特征时，才建议进行活检。在其2009年的立场文件中，AASLD重申了其对肝活检在诊断和治疗HCC中的作用的立场。根据这些实践指南，近年来许多肝癌患者要么没有病理报告，要么没有住院治疗，这损害了基于人群的癌症登记系统中肝癌报告的完整性，该系统严重依赖这些手段进行常规病例发现。 在加州，肝细胞癌的监测尤为重要，因为那里有大量的亚洲/太平洋岛民，他们患这种癌症的风险很高。最近发表的一项对加州癌症趋势的分析显示，虽然亚洲/太平洋岛民的发病率最高，但1988年至2005年期间，所有种族/民族和性别群体的肝癌发病率都有所增加。如果HCC是未确诊的，并且由于最近诊断实践的变化，未确诊的病例正在增加，那么我们可能低估了问题的严重性。加州也是亚裔美国人癌症意识、研究和培训网络（AANCART）的所在地。目前的一个AANCART项目是在高危人群中增加对B型肝炎的筛查。如果HCC不完全确定，则对这种干预的评估存在风险。 鉴于这些肝癌临床指南是相当新的，并且它们是建议而不是要求，它们对肝癌报告完整性的影响在癌症登记报告中可能还不明显。早期的HCC评估报告称，2000年至2007年诊断的909例HCC病例中有51例（6%）被具有统一记录的医院和SEER登记处遗漏。大多数被医院登记处遗漏的HCC病例都通过放射学确诊。科学家们最近对2009年肝移植计划中的60例HCC患者与注册数据库进行了有限的联系。他们在这个数据库中没有发现24例（40%）病例的记录。较高比例的缺失病例可能是因为之前研究中的医院登记员可以访问其患者的统一病历，而本研究中的登记员主要依赖病理报告进行病例发现。PHI将进一步调查这些和其他潜在的缺失HCC病例，并确定当前肝癌登记研究病例发现和病例报告机制的系统性不足之处，与肝癌的新兴临床实践模式有关。

Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer in both children and adults, accounting for 90% of all liver cancers. It is the third leading cause of cancer-related mortality worldwide and the incidence of HCC has been rising in the United States and Europe over the past decades. In the U.S., liver cancer is among the top 10 most common cancers with the highest incidence rates among Asian Americans. Chronic infection with hepatitis B virus (HBV) or hepatitis C virus (HCV) is by far the most important risk factor for liver cancer. Clinical practice guidelines for the diagnosis, staging and treatment of HCC did not exist in the U.S. until the 2005 publication of the practice guideline for the management of hepatocellular carcinoma developed by the American Association for the Study of Liver Diseases (AASLD). The guideline recommended the use of ultrasound, CT scan, and MRI for the diagnosis of HCC with typical features. Biopsy is considered unnecessary if the imaging tests show typical features of HCC. Biopsy is recommended only when the vascular profile on imaging is not characteristic of HCC. In its 2009 position paper, the AASLD reaffirmed its stance on the role of liver biopsy in diagnosing and treating HCC. Under these practice guidelines, many liver cancer patients in recent years either do not have pathology reports or are not hospitalized for treatment, which jeopardizes completeness of liver cancer reporting in the population-based cancer registry system that heavily relies on these means for routine case-finding. Surveillance for HCC is of particular importance in California which has a large Asian/Pacific Islander population at high risk for this cancer. A recent published analysis of cancer trends in California showed while incidence rates were highest among Asian/Pacific Islanders, there was an increase of liver cancer in all race/ethnicity and gender groups between 1988 and 2005. If HCC is under ascertained, and if that under ascertainment is increasing because of recent changes in diagnostic practice, then we may be underestimating the magnitude of the problem. California also is the home of the Asian American Network for Cancer Awareness, Research and Training (AANCART). A current AANCART project is to increase screening for Hepatitis B in high risk populations. Evaluation of this intervention is at risk if HCC is incompletely ascertained. Given that these clinical guidelines for liver cancer are rather recent and that they are recommendations rather than requirements, their impact on the completeness of liver cancer reporting may have not yet been obvious in cancer registry reports. An earlier evaluation of HCC reported that 51 out of 909 (6%) of HCC cases diagnosed between 2000 and 2007 were missed by both the hospital which had a unified record and the SEER registries. Most of the HCC cases missed by the hospital registry were diagnostically confirmed by radiology. Scientists recently conducted a limited linkage of 60 HCC patients seen in 2009 at the Liver Transplant Program with the registry database. They found no records in this database for 24 (40%) of these cases. The higher proportion of missing cases is likely because the hospital registrars in the previous study has access to the unified medical records for their patients, registrars in this study depend primarily on pathology reports for casefinding. PHI will further investigate these and other potential missing HCC cases and identify systematic inadequacies in the current registry case-finding and case-reporting mechanisms for liver cancer, in relation to the emerging clinical practice patterns of liver cancer.