目的 :提高对原发性膀胱恶性淋巴瘤的早期诊断。方法 :通过免疫组化方法对 4例原发性膀胱恶性淋巴瘤进行病理分型 ,并对其临床表现、诊断、治疗及预后进行讨论。结果 :临床主要表现 :血尿、排尿困难、尿频。膀胱镜检查可见片状或半球形规则或不规则突起 ,表面粘膜常光滑。4例经免疫组化检查均为B细胞淋巴瘤 ,其中低度恶性粘膜相关淋巴瘤 3例 (CD2 0 + /CD10 - /CD5 - ) ,滤泡中心细胞淋巴瘤 1例 (CD2 0 + /CD10 + )。 4例患者存活期为 3 7年。结论 :膀胱恶性淋巴瘤主要为B细胞型 ,且以低度恶性粘膜相关淋巴瘤多见。膀胱镜检查粘膜大多光滑 ,隆起不明显时容易漏诊。明确诊断依靠病理活检 ,治疗采用手术切除 ,辅以放化疗 ,大部分患者预后好 Objective: To improve the early diagnosis of primary bladder malignant lymphoma. Methods: Four cases of primary malignant lymphoma of bladder were classified by immunohistochemistry and their clinical manifestations, diagnosis, treatment and prognosis were discussed. Results: The main clinical manifestations: hematuria, dysuria, frequent urination. Cystoscopy showed flaky or hemispherical rules or irregular protrusions, the surface mucosa often smooth. All the 4 cases were classified as B cell lymphoma by immunohistochemistry, including 3 cases of low grade mucosa - associated lymphoma (CD20 + / CD10 - / CD5 -), 1 case of follicular center cell lymphoma (CD20 + CD10 +). Four patients had a survival of 37 years. Conclusions: Bladder malignant lymphoma is mainly B cell type, and is more common in low grade mucosa-associated lymphoma. Most cystoscopy mucosa is smooth, easy to miss when the bulge is not obvious. Clear diagnosis rely on biopsy, the treatment of surgical resection, supplemented by radiotherapy and chemotherapy, most patients with good prognosis