OBJECTIVE This study aimed to investigate the prevalence and distribution of carcinoma in the liver margin (LM) of resected perihilar cholangiocarcinoma (pCCA) and establish a method for LM examination. BACKGROUND LM is the largest margin in resected pCCA with undefined status and assessment method. METHODS 227 pCCA cases underwent major hepatectomy were divided into a discovery cohort (n=101) assessed using serial whole-mount digital large sections (WDLS) combined with small sections, and a control cohort (n=126) assessed using only small sections. RESULTS The LM R1 resection rate was 38.6% (39/101) in the discovery cohort and 5.6% (7/126) in the control cohort. WDLS identified more LM R1 cases compared to the small section in the discovery cohort (38.6% vs. 5.9%, P<0.001). R0 patients in the discovery cohort had better overall survival and recurrence-free survival than those in the control cohort (both P<0.05). Additionally, 95% of carcinoma was found within 20 mm of the proximal ductal margin (DM). A proximal DM distance of<5 mm was an independent risk factor for LM R1 resection. Patients with which are more likely to experience R1 compared to those with ≥ 5 mm (P<0.001). CONCLUSIONS Positive LM was the significant cause for R1 resection of pCCA and the utilization of WDLS improved the diagnostic accuracy of LM. An examination methodology was established, highlighting the necessity of examining LM within a 20 mm radius around the proximal DM, especially in patients with a proximal DM of<5 mm.

中文翻译：

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肺门周围胆管癌的肝缘状况：一项多中心研究。


目的 探讨已切除的肺门周围胆管癌 （pCCA） 肝缘 （LM） 癌的患病率和分布，并建立 LM 检查方法。背景 LM 是未定义状态和评估方法的切除 pCCA 中的最大切缘。方法 将 227 例接受肝大切除术的 pCCA 病例分为使用连续整体数字大切片 （WDLS） 联合小切片评估的发现队列 （n=101） 和仅使用小切片评估的对照组 （n=126）。结果 发现队列中 LM R1 切除率为 38.6% （39/101），对照组为 5.6% （7/126）。与发现队列中的一小部分相比，WDLS 确定了更多的 LM R1 病例 （38.6% vs. 5.9%，P<0.001）。发现队列中的 R0 患者总生存期和无复发生存期均优于对照组 （均 P<0.05）。此外，95% 的癌症发生在近端导管边缘 （DM） 的 20 mm 范围内。近端 DM 距离 <5 mm 是 LM R1 切除术的独立危险因素。与 ≥ 5 mm 的患者相比，患者更可能经历 R1 （P<0.001）。结论 阳性 LM 是 r1 切除 pCCA 的重要原因，使用 WDLS 提高了 LM 的诊断准确性。建立了一种检查方法，强调了在近端 DM 周围 20 mm 半径内检查 LM 的必要性，尤其是对于近端 DM 为 <5 mm 的患者。