摘要
目的探讨伴有淋巴样间质的微结节型胸腺瘤(MNT)的临床病理学特点。方法对4例伴有淋巴样间质的微结节型胸腺瘤进行组织学观察和免疫组化染色,观察其临床影像学特点,并复习相关文献。结果 4例中,男女各2例,发病年龄52~69岁,平均61岁。CT均提示纵隔内胸腺区不规则软组织密度影,密度较均匀。肉眼观察:肿物最大径2~6 cm,切面实性,灰白、灰黄色,质地中等。镜下见肿瘤大部分包膜完整,境界清楚,只有1例一小处似有包膜侵犯;高倍镜下显示上皮样肿瘤细胞呈结节状分布,结节呈多发性散在或局部融合,细胞形态温和,呈短梭形或卵圆形,胞质粉染,细胞核卵圆形,核仁不明显,未见明显核异型及核分裂象。间质内可见丰富的淋巴细胞,部分区域可见初级淋巴滤泡或伴有生发中心的次级淋巴滤泡。免疫组化:结节内肿瘤细胞CK5/6、CK19、CD57和p63均(+),EMA(-);上皮细胞巢内可见个别CD3、Td T阳性的T淋巴细胞;淋巴间质内淋巴滤泡主要为CD20阳性的B淋巴细胞,CD3和CD5阳性的T淋巴细胞分布在淋巴滤泡间区,非生发中心区域尤其是套区bcl-2(+);Ki-67增殖指数在上皮性结节中低表达,在未成熟的淋巴细胞中高表达;并发现langerhans细胞标记物CD1α和Langerin在上皮细胞巢内散在星状分布。结论 MNT非常罕见,肿瘤细胞p63和CK5/6弥漫(+),推测MNT可能来源于胸腺髓质上皮细胞;另外本文主要强调MNT中langerhans细胞的增生及其特有的组织病理学特征,从而更好、更全面地了解这种罕见的肿瘤。
Objective To study the clinipathological features of micronodular thymoma with lymphoid stroma. Methods Four cases of micronodular thymoma with lymphoid stroma were studied by histology,immunohistochemistry and clinical imaging. Results There were 2 males and 2 females with ranging in age from 52 to 69 years（ mean 61 years old）.Computed tomography（ CT） all showed an irregular soft tissue density in thymic area,and the density was uniform. The tumors measured 2. 0 cm to 6. 0 cm in greatest dimension（ median,3. 375 cm）. They mostly appeared to be well circumscribed and encapsulated,only one case seemed to have a capsule violation in a small place. The cut surface of the tumors was light tan and solid,and this texture was medium. Microscopically,MNT was characterized by multiple,discrete or focally confluent nodules of epithelioid tumor cells separated by abundant lymphoid stroma with prominent germinal centers. The epithelial nodules were composed of slender or plump spindle cells with bland looking oval nuclei and inconspicuous nuleoli. Cell atypia and mitotic activity were absent or minimal. Immunohistochemical studies showed that strong positivity of the spindle epithelial tumor cells for CK5/6,CK19,CD57 and P63. Stains for EMA were negative in the spindle tumor cells. Individual CD3,TDT-positive T cells were visible in epithelial cell nests. Many lymphocytes in the stroma,including germinal centres,were positive for CD20. In contrast,many lymphocytes positive for CD3 and CD5 were even dispersed in the stroma. BCL-2 immunoreactivity was also detected in many lymphocytes in the stroma,especially in the mantle zone of lymphoid follicles. Ki-67 showed low expression in epithelial nodules,whereas high expression in lymphocytes areas. And we found that some CD1α ＋,langerin ＋ Langerhans cells were scarced within epithelial cell micronodules in a star-like pattern. Conclusions MNT is a very rare tumor but can be diagnosed with a characteristic morphology and immunoreactivity to p63 and CK5/6. We specul
出处
《诊断病理学杂志》
2017年第11期818-823,共6页
Chinese Journal of Diagnostic Pathology
基金
国家自然科学基金(81660393)
