探讨结直肠癌大胆管转移的病理特征及其与术后复发的关系。

回顾性分析2016年1月至2020年10月在中山大学孙逸仙纪念医院诊治的5例影像学检查发现大胆管内占位且经术后病理证实结直肠癌大胆管内转移患者临床资料。患者均签署知情同意书，符合医学伦理学规定。其中男4例，女1例；年龄48~59岁，中位年龄54岁。5例原发病灶均为左半结直肠，均同时合并肝实质转移灶，其中多发结节4例，单发结节1例。采用HE染色和免疫组化方法检测CK7、CK20和CDX2蛋白的表达。观察患者的病理特征、诊治及预后情况。

同期555例结直肠癌肝转移患者，大胆管转移发生率0.9%（5/555）。根据患者转移灶部位采用肝切除或病灶切除。病理学检查发现肝转移灶分化程度与原发灶相同，其中中度分化4例，低分化1例；扩张的大胆管内肿物填充，胆管转移灶组织形态与肝实质转移癌相同。胆管转移灶生长方式包括管腔内息肉状生长、癌细胞沿着胆管基底膜生长、肝外胆管孤立转移3种。免疫组化染色显示转移灶癌细胞CK20、CDX2均阳性，CK7阴性；残留胆管上皮CK7阳性，CK20、CDX2均阴性。术后3例复发，复发时间为术后8~32个月。

结直肠癌大胆管转移具有独特的病理形态和生物学行为，可沿胆管树连续性或非连续性播散。明确诊断,解剖性肝胆管切除,彻底清除受累肝胆管，以及术后密切监测，是改善预后的有效手段。

To investigate the pathological features and effect of colorectal cancer with large bile duct metastases on postoperative recurrence.

Clinical data of 5 patients who were detected with space-occupying masses in the large bile ducts by imaging examination and pathologically diagnosed with colorectal cancer and large bile duct metastases admitted to Sun Yat-sen Memorial Hospital of Sun Yat-sen University from January 2016 to October 2020 were retrospectively analyzed. The informed consents of all patients were obtained and the local ethical committee approval was received. Among them, 4 patients were male and 1 female, aged from 48 to 59 years, with a median age of 54 years. Primary lesions were located in the left colorectum in 5 patients, complicated with liver parenchymal metastases, including 4 cases of multiple nodules and 1 case of single nodule. The expression levels of CK7, CK20 and CDX2 proteins were measured by HE staining and immunohistochemistry. Pathological features, diagnosis and treatments, and clinical prognosis of the patients were observed.

Among 555 patients with liver metastases from colorectal cancer, the incidence rate of large duct metastasis was 0.9%(5/555). Liver resection or lesion resection was performed according to the location of metastatic lesions. Pathological examination showed that the degree of differentiation of liver metastases was the same to that of primary lesions, including 4 cases of moderately-differentiation and 1 case of lowly-differentiation. The dilated large bile duct was filled with masses, and the histological morphology of bile duct metastases was the same as that of liver parenchymal metastases. The growth patterns of bile duct metastases consisted of intraductal polypoid growth, cancer cell growth along with the bile duct basement membrane and isolated extrahepatic bile duct metastasis. Immunohistochemical staining demonstrated that CK20 and CDX2 in the metastatic cancer cells were positive, whereas CK7 negative. The residual bile duct epithelium was positive for CK7, whereas negative for CK20 and CDX2. 3 cases recurred between postoperative 8 and 32 months.

Large bile duct metastasis from colorectal cancer is manifested with typical pathological morphology and biological behavior, which can spread along with the biliary tree in a continuous or discontinuous pattern. Definite diagnosis, anatomical resection of hepatobiliary ducts, complete removal of the involved bile ducts, and intimate postoperative monitoring are effective approaches to improve the patients' prognosis.