Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden.
Department of Pathology and Molecular Medicine, Wellington School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand.
Histopathology. 2018 Jul;73(1):8-18. doi: 10.1111/his.13471. Epub 2018 Mar 5.
Despite efforts to standardise grading of prostate cancer, even among experts there is still a considerable variation in grading practices. In this study we describe the use of Pathology Imagebase, a novel reference image library, for setting an international standard in prostate cancer grading.
The International Society of Urological Pathology (ISUP) recently launched a reference image database supervised by experts. A panel of 24 international experts in prostate pathology reviewed independently microphotographs of 90 cases of prostate needle biopsies with cancer. A linear weighted kappa of 0.67 (95% confidence interval = 0.62-0.72) and consensus was reached in 50 cases. The interobserver weighted kappa varied from 0.48 to 0.89. The highest level of agreement was seen for Gleason score (GS) 3 + 3 = 6 (ISUP grade 1), while higher grades and particularly GS 4 + 3 = 7 (ISUP grade 3) showed considerable disagreement. Once a two-thirds majority was reached, images were moved automatically into a public database available for all ISUP members at www.isupweb.org. Non-members are able to access a limited number of cases.
It is anticipated that the database will assist pathologists to calibrate their grading and, hence, decrease interobserver variability. It will also help to identify instances where definitions of grades need to be clarified.
尽管人们努力使前列腺癌分级标准化，但即使在专家之间，分级实践仍存在相当大的差异。在这项研究中，我们描述了使用 Pathology Imagebase，一种新的参考图像库，为前列腺癌分级制定国际标准。
国际泌尿病理学会（ISUP）最近推出了一个由专家监督的参考图像数据库。一个由 24 名国际前列腺病理专家组成的小组独立地对 90 例前列腺针吸活检癌症的显微照片进行了审查。50 例达成了线性加权κ值为 0.67（95%置信区间= 0.62-0.72）和共识。观察者间加权κ值从 0.48 到 0.89 不等。在 GS 3 + 3 = 6（ISUP 分级 1）方面达成了最高水平的共识，而较高的分级，特别是 GS 4 + 3 = 7（ISUP 分级 3）则存在相当大的分歧。一旦达到三分之二的多数，图像将自动移动到公共数据库中，所有 ISUP 成员都可以在 www.isupweb.org 上访问。非成员可以访问有限数量的病例。
预计该数据库将有助于病理学家校准其分级，从而减少观察者间的变异性。它还将有助于确定需要澄清等级定义的情况。
