中文摘要：

食管碰撞瘤是指两个独立肿瘤的相互碰撞，很罕见。碰撞瘤的病理生物学机制仍不清楚。临床症状、内镜检查及影像学检测均缺乏特异性，术前诊断困难。详尽的病理学检查对于作出准确的诊断、进行针对性的治疗并获得较好的预后至关重要。近年来，有关食管碰撞瘤的病例报道逐渐增多，为提高对本病的认识，其临床病理特征有待进一步总结。

英文摘要：

Esophageal collision tumor is an extremely rare tumor which defined as the two distinct primary neoplasms. The pathobiological mechanism of collision tumors is yet to be understood. Clinical symptoms, endoscopic examination and imaging are all lack of specificity. Diagnosing a collision tumor prior to surgery is difficult. Careful pathological examination is crucial for accurately diagnosing the neoplasms in a collision tumor and ensuring appropriate management and a favorable prognosis. Esophageal collision tumors have been increasingly reported in recent years. With the aim of improving the knowledge level of eso- phageal collision tumor, the clinical and pathological features of this tumor is needed to be summarized.