Division of Medical Oncology, Japanese Red Cross Musashino Hospital, 1-26-1, Kyonan-cho, Musashino-shi, Tokyo, 180-8610, Japan.
Division of Breast and Medical Oncology, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa-Shi, Chiba, 277-8577, Japan.
Breast Cancer. 2018 Jan;25(1):118-125. doi: 10.1007/s12282-017-0799-3. Epub 2017 Aug 30.
The degree of pathological response to neoadjuvant chemotherapy (NAC) was correlated with the prognosis in breast cancer. There are few studies published on inter-observer variability in the assessment of pathological responses among pathologists.
We collected 64 surgically resected specimens from patients who had received NAC. Three pathologists assessed the pathological responses and classified them into 7 grades according to grading system of the Japanese Breast Cancer Society. The levels of concordance among pathologists were categorized into 3 classes: full concordance (all pathologists gave the same grade), partial concordance (two of them gave the same grade), and discordance (all three gave different grades). The inter-observer agreement among pathologists was estimated using the percentage concordance and Cohen's kappa statistics.
Full concordance, partial concordance, and discordance were seen in 28 (43%), 33 (52%), and 3 (5%) specimens, respectively. In most of partial concordance specimens (30 out of 33), the pathological response grades differed by only one level. The kappa value was 0.59. The concordance rate with regard to pCR was 97%.
Most of the judgments among pathologists differed within one level, but there is room for improving harmonization in the assessment of pathological responses.
新辅助化疗（NAC）的病理反应程度与乳腺癌的预后相关。在病理学家评估病理反应的观察者间变异性方面，发表的研究较少。
我们收集了 64 例接受 NAC 治疗后手术切除的标本。3 名病理学家根据日本乳腺癌学会的分级系统评估病理反应，并将其分为 7 个等级。将病理学家之间的一致性水平分为 3 类：完全一致（所有病理学家均给出相同的等级）、部分一致（其中 2 位给出相同的等级）和不一致（所有 3 位给出不同的等级）。采用一致性百分比和 Cohen's kappa 统计评估病理学家之间的观察者间一致性。
分别有 28 例（43%）、33 例（52%）和 3 例（5%）标本完全一致、部分一致和不一致。在大多数部分一致的标本（33 例中的 30 例）中，病理反应等级仅相差一级。kappa 值为 0.59。pCR 的一致性率为 97%。
大多数病理学家的判断差异仅为一级，但在评估病理反应方面仍有提高协调性的空间。
