在个体化胃癌（GC）治疗时代，准确确定组织学亚型变得越来越重要。迄今为止，尚不清楚术前化疗是否会影响组织学亚型。本研究的目的是评估围手术期治疗前后治疗前活检和手术切除标本之间组织学亚型的一致性。组织学亚型集中在仅接受任一手术治疗的患者的配对 GC 活检和手术切除标本中确定（SA ）在荷兰 D1/D2 研究中或在 CRITICS 试验中与术前化疗 (CT) 一起使用。切除标本中确定的组织学亚型被认为是金标准。分析了 GC 的肠道亚型、弥漫性亚型、混合亚型和“其他”GC 亚型的一致性率以及敏感性和特异性。总共分别纳入了 SA 和 CT 队列中治疗的患者的 105 对和 515 对 GC 活检和切除标本。组织学亚型的总体一致性在 SA 中为 72%，在 CT 队列中为 74%，与肠道亚型（70% 和 74%）、混合亚型（21% 和 74%）相比，弥漫型（83% 和 86%）显着更高。 33%）和“其他”亚型（54% 和 54%）。在 SA 队列中，肠道亚型的敏感性和特异性分别为 0.88 和 0.71，弥漫性亚型为 0.67 和 0.93，混合亚型为 0.20 和 0.98，“其他”亚型为 0.50 和 0.93。我们的结果表明，准确测定胃癌活检的组织学亚型不是最理想的，但术前化疗对组织学亚型的影响可以忽略不计。© 2023。作者。

In the era of individualized gastric cancer (GC) treatment, accurate determination of histological subtype becomes increasingly relevant. As yet, it is unclear whether preoperative chemotherapy may affect the histological subtype. The aim of this study was to assess concordance in histological subtype between pretreatment biopsies and surgical resection specimens before and after the introduction of perioperative treatment.Histological subtype was centrally determined in paired GC biopsies and surgical resection specimens of patients treated with either surgery alone (SA) in the Dutch D1/D2 study or with preoperative chemotherapy (CT) in the CRITICS trial. The histological subtype as determined in the resection specimen was considered the gold standard. Concordance rates and sensitivity and specificity of intestinal, diffuse, mixed, and "other" subtypes of GC were analyzed.In total, 105 and 515 pairs of GC biopsies and resection specimens of patients treated in the SA and CT cohorts, respectively, were included. Overall concordance in the histological subtype was 72% in the SA and 74% in the CT cohort and substantially higher in the diffuse subtype (83% and 86%) compared to the intestinal (70% and 74%), mixed (21% and 33%) and "other" subtypes (54% and 54%). In the SA cohort, sensitivities and specificities were 0.88 and 0.71 in the intestinal, 0.67 and 0.93 in the diffuse, 0.20 and 0.98 in the mixed, and 0.50 and 0.93 in the "other" subtypes, respectively.Our results suggest that accurate determination of histological subtype on gastric cancer biopsies is suboptimal but that the impact of preoperative chemotherapy on histological subtype is negligible.© 2023. The Author(s).