儿童型滤泡性淋巴瘤八例临床病理及分子遗传学特征

摘要

Objective To investigate the clinical presentation pathological diagnostic features and molecular genetics of paediatric?type follicular lymphoma (PTFL). Methods Eight cases of PTFL at Fujian Cancer Hospital between January 2003 and May 2018 were analyzed by hematoxylin?eosin stain, immunohistochemistry, polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH). The relevant literature review was performed. Results All patients were male with age ranging from 12 to 27 years (median age of 18 years and average age of 19 years). Clinical manifestations included painless lymph adenopathy, primarily involving head and neck lymph nodes (6/8). According to Ann Arbor stage, there were 7 patients at stage ⅠA and 1 patient at stage ⅡA. Histologically, the structure of the lymph nodes was effaced with pushing borders visible at the tumor periphery. The lesions consisted of expanding, irregular follicles that were arranged in back to back fashion along with thinning or disappearing sleeves. The starry sky phenomenon in the follicle was prominent with loss of polarity. Under high power magnification, the follicles were composed of uniform, medium?sized blastic cells in 5 cases or centroblast in 3 cases. The neoplastic cells were positive for B cell markers and germinal center markers primarily confined to the germinal center. Bcl?2 was negative in 7 cases and 1 case showed weak bcl?2 staining. MUM1 was negative in all cases. Ki?67 demonstrated a high proliferation index of great than 70% in 7 of 8 cases. Eight cases showed Ig clonal rearrangement. No bcl?2, bcl?6, and IRF4/MUM1 gene rearrangements by FISH were detected in all cases. One patient was treated with 6 cycles of CHOP after surgical resection. Other patients underwent only simple surgical resection. All patients were alive upon clinical follow?up. Conclusion PTFL is a rare subtype of B cell lymphoma with unique clinical and pathological features. It should be distinguished from reactive follicular hyperplasia, nodal marginal lymphoma in children, large B?cell lymphoma with IRF4 rearrangement and usual follicular lymphoma.%目的 探讨儿童型滤泡性淋巴瘤(paediatric?type follicular lymphoma,PTFL)的临床病理特点及分子遗传学特征.方法 收集福建省肿瘤医院病理科2003年1月至2018年5月诊断的8例PTFL石蜡标本,采用HE染色、免疫组织化学、聚合酶链反应(PCR)及荧光原位杂交的方法,观察组织学、免疫表型及分子遗传学特征,并结合文献进行复习.结果 8例PTFL患者均为男性,年龄12～27岁,中位年龄18岁.临床主要表现为头颈部无痛性淋巴结肿大(6/8).Ann Arbor分期,其中7例ⅠA期,1例ⅡA期.低倍镜下,淋巴结结构破坏,周边见推挤性边缘,滤泡膨大扩张、不规则,排列紧密,背靠背,套区变薄或消失,星空现象显著,极性消失.高倍镜下,滤泡内以单一中等大小的母细胞为主(5/8),部分以中心母细胞为主(3/8).肿瘤细胞表达全B细胞标志物及生发中心标志物CD10、bcl?6,且多局限于生发中心.bcl?2通常阴性(7/8),少数病例局灶弱阳性(1/8),MUM1阴性.Ki?67阳性指数高,多数大于70%(7/8).Ig基因重排均阳性.bcl?2、bcl?6、IRF4/MUM1基因分离均阴性.7例单纯手术切除淋巴结,1例术后行6个周期CHOP(环磷酰胺、长春新碱、吡柔比星、地塞米松)方案治疗.目前8例患者均无病生存.结论 PTFL是一种少见并具有独特的临床病理和分子遗传学特征的B细胞淋巴瘤,应与反应性滤泡增生、儿童淋巴结边缘区淋巴瘤、伴IRF4重排的大B细胞淋巴瘤以及滤泡性淋巴瘤等鉴别,避免漏诊、误诊和过度治疗.