【摘要】 目的分析弥漫大B细胞淋巴瘤（DLBCL）¹⁸F-FDG PET/CT显像特征,并探讨¹⁸F-FDG PET/CT对DLBCL的诊断价值。方法 48例经病理确诊为弥漫大B细胞淋巴瘤的患者化疗前均行¹⁸F-FDG PET/CT全身显像。采用Fisher确切概率法比较PET/CT融合图像及同机CT图像诊断淋巴结和结外组织、器官受累的敏感性。结果DLBCL肿大淋巴结在PET/CT融合图像表现为单个或多个类圆形软组织密度结节影,部分淋巴结内见钙化点,边界清楚,部分肿大淋巴结相互融合成形状不规则的肿块时,边界欠清楚;累及的结外组织器官大多数结构改变较为隐秘或无明显改变;病灶摄取¹⁸F-FDG明显增高,呈结节样或团块样放射性浓聚;淋巴结或结外受累病灶内部出现坏死时,坏死部位形成圆圈样的¹⁸F-FDG摄取增高灶。PET/CT融合图像与同机CT图像诊断DLBCL淋巴结受累敏感性分别为94.85%、82.35%;诊断结外组织器官受累敏感性分别为95.23%、21.43%,两者比较P均<0.05。结论DLBCL¹⁸F-FDG PET/CT显像典型的影像特征是:淋巴结显示为单个或多个类圆形软组织密度结节影并摄取¹⁸F-FDG明显增高,肿大的淋巴结相互融合或呈融合趋势,部分形成不规则的肿块,少数肿大淋巴结内可见钙化点;受累结外组织器官出现或不出现结构改变,但摄取¹⁸F-FDG明显升高。PET/CT融合图像较同机CT图像诊断DLBCL累及的淋巴结或结外组织器官更加敏感,但仍存在一定的假阳性和假阴性。更多还原

【Abstract】 Objective To analyze the imaging features of¹⁸F-FDG PET/CT in diffuse large B-cell lymphoma（ DLBCL） and to discuss its value in diagnosis of DLBCL. Methods Forty-eight cases of patients with DLBCL confirmed by pathology underwent whole-body¹⁸F-FDG PET/CT scan before chemotherapy. We compared the sensitivity of PET/CT fusion image and CT image in diagnosis of lymph nodes,extranodal tissues and organ involvements by the Fisher’s exact probability test. Results Enlarged lymph nodes of DLBCL in PET/CT fusion images manifested as single or multiple rounded soft tissue density nodular images,part of the lymph nodes calcified,border was clear,and part of the boundary was less clear when the enlarged lymph nodes fused into irregular-shaped lump; most of the involved tissues and organs’ structural changes were relatively hidden or not significant; lesion uptake of¹⁸F-FDG was significantly higher,which showed nodular or mass sample radioactive concentration. When the necrosis was found in lymph nodes or extranodal involvements,necrosis would form a circular-like¹⁸F-FDG uptake increased foci. The diagnosis sensitivity of PET/CT fusion image and CT image to DLBCL lymph node involvements was 94. 85% and 94. 85%,which was 95. 23% and 21. 43% to extranodal involvements,and significant difference was found between these two groups（ all P < 0. 05）. Conclusions The typical characteristics of¹⁸F-FDG PET/CT imaging of DLBCL are: lymph nodes display as single or multiple round soft tissue density nodular images and uptake¹⁸F-FDG obviously increases,the enlarged lymph nodes can fuse or show fusion trend,and part of them form irregular-shaped lump,and calcification can be found within a few of the lymph nodes. The uptake18 FFDG obviously increase when the involved tissues and organs had or not had structural changes. Using PET/CT fusion images diagnosing lymph nodes and organs involved is more sensitive than CT,but there are still some false positives and false negatives.更多还原