Abstract:
An asymptomatic 75-year-old man who underwent transverse colon cancer surgery two years previously presented with retroperitoneal fibrosis (RPF) around the ventral sacral and right external iliac artery and vein on abdominal computed tomography (CT) during a routine surveillance visit. We assumed cancer recurrence or immunoglobulin G4 (IgG4)-related disease (RD), but although generic tumor markers and IgG4 levels were normal, soluble interleukin 2 receptor (sIL-2R) was elevated at 569 U/mL (reference: 122-496 U/mL). No diagnosis was made at this time, and the patient was followed up. He subsequently developed edema of both lower extremities. Abdominal enhanced CT showed an enlarged RPF without invasion of surrounding organs and with a delayed contrast effect, and positron emission tomography-CT showed fluorodeoxyglucose accumulation in the same area but a lower standardized uptake value (SUV) than at the time of transverse colon cancer diagnosis. Although generic tumor markers and IgG4 levels remained within the reference range, sIL-2R was further elevated to 1100 U/mL. An open biopsy and histopathology showed a high IgG4/IgG-positive cell ratio and infiltration of IgG4-positive plasma cells. The patient was finally diagnosed with IgG4-RD RPF. In cases of RPF after colorectal cancer surgery, the combined findings of elevated sIL-2R, lack of infiltration into surrounding organs, and lower SUV values than at the cancer site could provide useful information to aid the diagnosis of IgG4-RD RPF.
摘要:
一名无症状的75岁男子,两年前接受了横结肠癌手术,在常规监测访视期间,腹部计算机断层扫描(CT)显示腹侧骶骨和右髂外动脉和静脉周围腹膜后纤维化(RPF)。我们假设癌症复发或免疫球蛋白G4(IgG4)相关疾病(RD),但尽管肿瘤标志物和IgG4水平正常,可溶性白细胞介素2受体(sIL-2R)升高至569U/mL(参考:122-496U/mL)。目前还没有诊断,对病人进行了随访。他随后出现了下肢水肿。腹部增强CT显示RPF增大,未侵犯周围器官,并有延迟的对比效果,和正电子发射断层扫描-CT显示氟脱氧葡萄糖在同一区域积累,但标准化摄取值(SUV)低于横结肠癌诊断时。尽管通用肿瘤标志物和IgG4水平仍在参考范围内,sIL-2R进一步升高至1100U/mL。开放活检和组织病理学显示高IgG4/IgG阳性细胞比率和IgG4阳性浆细胞浸润。患者最终被诊断为IgG4-RDRPF。在结直肠癌手术后RPF的情况下,sIL-2R升高的综合发现,缺乏对周围器官的渗透,低于癌症部位的SUV值可以提供有用的信息来帮助诊断IgG4-RDRPF。