Pathology Department, University Hospital of Saint-Etienne, Saint-Etienne, France.
Pathology Department, University Hospital of Saint-Etienne, Saint-Etienne, France.
Pathol Res Pract. 2022 Sep;237:154042. doi: 10.1016/j.prp.2022.154042. Epub 2022 Jul 27.
PD-L1 immunohistochemical expression is used as an important theranostic marker in various malignancies, including head and neck squamous cell carcinoma (HNSCC) where the combined positive score (CPS) guides treatment decisions. Despite indirect evidence that there is loss of antigenicity for archived tissues, there is no direct comparison between PD-L1 expression of the same tissue upon arrival and after its storage.
We compared the immunohistochemical expression of PD-L1 (22C3) in 106 HNSCC upon their arrival and after their storage (interval ranging from 20 to 48 months, mean 30.8 months). The evaluation was performed by two different pathologists' groups.
We found a statistically significant decrease in the PD-L1 tumor proportional score (TPS), immune cells expression (IC) and CPS between the initial and the newly stained slides.
This is the first study comparing PD-L1 expression between a tissue and "himself" later in time, highlighting an important decrease in expression by tumor and immune cells, and suggesting that an immediate rather than a retrospective assay of PD-L1 expression should be preferable in the routine practice.
Data are available upon reasonable request.
PD-L1 免疫组化表达被用作各种恶性肿瘤的重要治疗标志物，包括头颈部鳞状细胞癌（HNSCC），其中联合阳性评分（CPS）指导治疗决策。尽管有间接证据表明存档组织的抗原性丧失，但对于同一组织在到达后和储存后的 PD-L1 表达，尚无直接比较。
我们比较了 106 例 HNSCC 组织在到达后和储存后（间隔 20 至 48 个月，平均 30.8 个月）的 PD-L1（22C3）免疫组化表达。评估由两名不同的病理学家小组进行。
我们发现初始和新染色切片之间 PD-L1 肿瘤比例评分（TPS）、免疫细胞表达（IC）和 CPS 存在统计学显著降低。
这是第一项比较组织与其自身在不同时间点 PD-L1 表达的研究，突出了肿瘤和免疫细胞表达的重要降低，表明在常规实践中，应更倾向于立即而不是回顾性检测 PD-L1 表达。
数据可应合理要求提供。
