Department of Pathology, Zhongshan Hospital, Fudan University, Shanghai, China.
Department of Pathology, Henan Cancer Hospital, Zhenghou, Henan, China.
Diagn Pathol. 2022 Jun 28;17(1):54. doi: 10.1186/s13000-022-01230-7.
Former single center studies indicated that HER2 assessment with two primary tumor blocks (dual block HER2 assessment) could be an efficient and practical approach to overcome the adverse impact of heterogeneity and acquire a HER2 positive rate in gastric cancer (GC). This multicenter prospective clinical trial (NCT02843412) was launched to verify its value and generality.
A total of 3806 participants with primary GCs have been enrolled from 8 hospitals in China. Two primary tumor blocks were selected and recorded as block 1 and block 2 after histological evaluation. An HER2 (4B5) rabbit monoclonal antibody was used for the immunohistochemistry (IHC) analysis.
In total patients, HER2 IHC positive (3+) rate with dual block assessment (9.4%) was higher than that with single block assessment (block 1: 7.8%, block 2: 7.8%) (P < 0.001). Compared with single-block assessment, dual-block assessment increased the positive rate by approximate 20%. Similarly, HER2 equivocal (2+) rate was increased in dual block assessment (25.8%), which was higher than that in single block assessment (block 1: 20.3%, block 2: 20.9%) (P < 0.001). Conversely, dual block assessment demonstrated a lower HER2 negative (0/1+) rate (64.8%) than single block assessment (block1: 71.9%, block 2: 71.3%) (P < 0.001). These findings were also confirmed in individual hospitals.
Dual block HER2 assessment effectively increased HER2 IHC positive rate in resected specimens of GC. We recommended dual block HER2 assessment be promoted in routine clinical practice in GC.
ClinicalTrials.gov, NCT02843412 . Registered 1 July 2016 - Retrospectively registered.
以前的单中心研究表明，使用两个原发性肿瘤块进行 HER2 评估（双块 HER2 评估）可以是一种有效且实用的方法，可以克服异质性的不利影响，并获得胃癌（GC）的 HER2 阳性率。这项多中心前瞻性临床试验（NCT02843412）旨在验证其价值和普遍性。
从中国的 8 家医院共招募了 3806 名原发性 GC 患者。在组织学评估后，选择并记录两个原发性肿瘤块作为块 1 和块 2。使用 HER2（4B5）兔单克隆抗体进行免疫组织化学（IHC）分析。
在所有患者中，双块评估的 HER2 IHC 阳性（3+）率（9.4%）高于单块评估的 HER2 IHC 阳性（3+）率（块 1：7.8%，块 2：7.8%）（P<0.001）。与单块评估相比，双块评估使阳性率增加了约 20%。同样，双块评估的 HER2 不确定（2+）率也有所增加（25.8%），高于单块评估的 HER2 不确定（2+）率（块 1：20.3%，块 2：20.9%）（P<0.001）。相反，双块评估的 HER2 阴性（0/1+）率（64.8%）低于单块评估（块 1：71.9%，块 2：71.3%）（P<0.001）。这些发现也在各个医院得到了证实。
双块 HER2 评估有效地提高了 GC 切除标本中 HER2 IHC 阳性率。我们建议在 GC 的常规临床实践中推广双块 HER2 评估。
ClinicalTrials.gov，NCT02843412。2016 年 7 月 1 日注册-回顾性注册。
