摘要目的:探讨食管基底细胞型异型增生的临床病理特征。方法:收集2009—2019年解放军联勤保障部队第九八九医院平顶山医疗区食管基底细胞型异型增生71例，收集临床病理资料，观察组织形态学特征和免疫表型，并结合文献进行探讨。结果:患者男女比例为1.6∶1.0，中位年龄65岁（范围48~81岁）。肿瘤位于食管上段4例（5.6%）、中段54例（76.1%）、下段13例（18.3%）。肿瘤中位最大径12.0 mm（范围3~42 mm），巴黎分型0~Ⅱb型占42.3%（30/71）。内镜下病变色泽发红及黏膜微血管异常。组织学上，肿瘤细胞小，核质比高，类似于基底细胞，细胞形态一致。结构异型性表现为肿瘤细胞密集，排列紊乱，基底层细胞极性丧失，无正常鳞状上皮的成熟分化梯度。10例肿瘤仅仅局限于上皮层的下部分，肿瘤细胞体积更小，形态更温和，常见上皮突向固有膜浅层生长；61例肿瘤至少局部波及了上皮层的全层。31例肿瘤伴浅表浸润性癌，癌的类型包括经典型鳞状细胞癌、基底样鳞状细胞癌、小细胞神经内分泌癌、鳞状细胞癌伴皮脂腺样癌和腺/导管上皮样癌分化。免疫组织化学染色显示肿瘤p53蛋白的突变型表达率为41.5%（17/41）。Ki-67异常分布模式41例（100.0%）。原病理诊断为低级别异型增生18例和不典型性上皮细胞12例，高级别异型增生及浅表浸润性癌41例。结论:基底细胞型异型增生具有独特的形态学特征，代表了食管鳞状上皮异型增生细胞形态学谱系中的一种肿瘤亚型。基底细胞型肿瘤细胞，尤其是仅分布在上皮层下半部分的肿瘤细胞，可能是食管癌发生的最早期阶段的肿瘤干细胞，具有多向分化潜能。当肿瘤仅局限于鳞状上皮层的下半部分时，它不符合当前WHO分类定义的食管鳞状上皮异型增生的诊断标准。

abstractsObjective:To investigate the clinicpathological features of basal cell type dysplasia of the esophagus.Methods:The clinicopathological data of 71 cases of basal cell type dysplasia of esophagus were collected at the People′s Liberation Army Joint Logistics Support Force 989 Hospital, from 2009 to 2019, and the histomorphologic characteristics and immunophenotype were evaluated. The relevant literature was reviewed.Results:The ratio of male to female patients was 1.6∶1.0, and the median age was 65 years (range 48-81 years). The tumors were located in the upper segment of the esophagus in four cases (5.6%), the middle segment in 54 cases (76.1%), and the lower segment in 13 cases (18.3%).The median maximal tumor diameter was 12.0 mm (range 3-42 mm). According to Paris Classification, 0-Ⅱb accounted for 42.3% (30/71) of the cases. Under endoscope, the lesions were reddish with abnormal mucosal microvessels. Histologically, the neoplastic cells were small, with a high nuclear-cytoplasmic ratio, similar to basal cells, and uniform in morphology. The structural atypia was characterized by dense and disordered tumor cells, loss of basal cell polarity, and absence of normal squamous differentiation gradient. In 10 cases, the tumors were confined to the lower part of the epithelium. The tumor cells were smaller and more uniform in shape, and extend to the superficial lamina propria. Sixty-one tumors involved at least the entire layer of the upper cortex. There were 31 cases of neoplasms with superficial invasive carcinoma. The types of neoplasms included typical squamous cell carcinoma, basaloid squamous cell carcinoma, small cell neuroendocrine carcinoma, squamous cell carcinoma with sebaceous adenoid carcinoma, and differentiation of glandular/ductal epithelioid carcinoma. Immunohistochemical staining showed that the mutant expression rate of p53 protein was 41.5% (17/41). All 41 cases (100.0%) showed abnormal distribution pattern of Ki-67. According to the initial pathologic diagnosis, there were 18 cases of low grade dysplasia, 12 cases of atypical epithelial cells, and 41 cases of high grade dysplasia and superficially invasive carcinoma.Conclusions:Basal cell type dysplasia has unique morphologic characteristics and represents a tumor subtype in the morphologic lineage of esophageal squamous dysplasia. Tumor cells of basal cell type dysplasia, especially those distributed only in the lower part of the stratified squamous epithelium, may be tumor stem cells at the earliest stage of esophageal carcinogenesis and have multidirectional differentiation potential. When the tumor is confined to the lower part of the stratified squamous epithelium, it does not meet the diagnostic criteria for esophageal squamous dysplasia as defined by the current WHO classification.