直肠淋巴瘤与腺癌形成的碰撞瘤临床病理观察

目的介绍直肠碰撞瘤的组织学特点和临床表现,以提高对本病的认识。方法报道1例直肠淋巴瘤与腺癌碰撞瘤,进行组织学及免疫组化标记研究,并复习相关文献。结果患者女性,89岁。主要表现为低位性肠梗阻。在结直肠切除标本中,同一肿瘤内可见中分化管状腺癌和弥漫性大B细胞性淋巴瘤呈浸润性生长,两种成分界限清楚,彼此靠近,互相融合,形成碰撞瘤。腺癌表达上皮性标记物,而淋巴瘤表达B细胞抗体,PAX-5两者均呈(+)。结论肠道碰撞瘤十分罕见。直肠淋巴瘤与腺癌的碰撞瘤,代表了两种独立成分彼此碰撞。临床需要提高认识,识别这类罕见肿瘤,并根据不同成分制定合适的治疗方案。

Rectal lymphoma and adenocarcinoma(collision tumor):a clinicopathological analysis

Objective To introduce the histopathological and clinical features of collision tumor of the rectum,and to improve the understanding of this disease.Methods A case of rectal lymphoma and adenocarcinoma collision tumor was observed by using HE and immunohistochemistry with review of the related literatures.Results A 89-year-old woman presented with low-set bowel obstruction.The colorectal resection specimen contained a moderately differentiated tubular adenocarcinoma.The adenocarcinoma was in continuity with a diffuse infiltrate consisting of diffuse large B-cell lymphoma cells.Though coexistent,the two tumor phenotypes respected their boundaries with no diffuse intermingling or transition between them.The adenocarcinoma strongly expressed the epithelial markers,the lymphoma revealed positivity with antibodies to B cell,and both tumors contained PAX-5 positive cells.Conclusion Collision tumors of the intestinal tract are rare.To the best of our knowledge,this is the fourth case reported of a rectum collision tumor composed of adenocarcinoma and lymphoma,representing an example of two independent tumors in a unique one-on-another collision.Our report highlights the need for pathologists,surgeons,and oncologists to be aware of the rare possibility of collisions tumors.Clinical awareness and recognition of such tumors are important as they will dictate appropriate treatment strategies dependent on the individual biological aggressiveness of each of the tumor components.