横纹肌肉瘤的CT与MRI影像学表现探讨

A study on the diagnosis of rhabdomyosarcoma using CT and MRI

目的探讨横纹肌肉瘤(RMS)的CT及MRI特点,分析不同病理分型之间的影像学表现。方法回顾性分析本院手术病理证实的20例横纹肌肉瘤患者,15例(15/20)有CT检查,12例(12/20)有MRI扫描,其中6例同时具有CT及MRI资料,观察病灶的位置、大小、数目、范围、CT及MR平扫强化程度及均匀度、囊变、坏死、出血、钙化、骨质破坏、转移及围血管征象,并比较不同病理分型间的影像学差异。结果 20例病例中,年龄中位数为24.5岁,均为单发病灶,病变位置在泌尿生殖系统25﹪(5/20),腹腔15﹪(3/20),头颈部45﹪(9/20),四肢5﹪(1/20),躯干10﹪(2/20)。CT平扫密度不均匀占64﹪(9/14),均为不均匀强化,轻度强化占60﹪(6/10),MRI平扫信号不均匀占64﹪(9/12),动态增强曲线均为速升平台型(9/9)。病灶内出现囊变坏死占75﹪(15/20),出血占25﹪(5/20),未见钙化,围血管征象占93﹪(14/15),周围骨质破坏占40﹪(8/20),淋巴结转移占35﹪(7/20),肺内转移及胸膜转移各1例,肺内及肝脏转移有1例。结论 RMS是一种儿童及青少年男性多见,全身软组织均可发病的恶性肿瘤,不同病例分型间影像学表现为囊实性肿块,增强扫描轻中度强化为主,动态增强扫描对病灶诊断有一定指导意义,多种影像学方法结合可以提高诊断的准确性。

Objective To investigate the CT and MRI features of rhabdomyosarcoma（RMS）and analyze the imaging findings of different pathological types. Methods Retrospective analysis was performed on 20 cases of pathologically confirmed rhabdomyosarcoma in our hospital, including 15 cases（15/20）of CT scans, 12 cases（12/20）of MRI scans, 6 cases of which had both CT and MRI data. In this study, the location, size, number, range, enhancement and uniformity in the CT and MR plain scans, cystic degeneration, necrosis, hemorrhage, calcification, bone destruction, metastasis, and perivascular signs were all evaluated and differences between different pathological subtypes were compared. Results Among the 20 cases, the median age was 24.5 years, all were found to have single lesion. The lesion locations included was genitourinary system 25 %5/20）, abdominal cavity and retroperitoneum 15 %3/20）, head and neck area 45 %9/20）, limbs 5 %1/20）, and trunk 10 %2/20）. 64 %9/14）of the lesions showed non-uniformly enhanced; 60 %6/10）showed mild enhancement, 64 %9/12）showed non-uniform signal intensity in MRI plain scan, all of which also had a fastrising plateau type enhancement curve. Cystic necrosis was found within the lesion in 75 %15/20）, hemorrhage found in 25 %5/20）（no calcification）, perivascular signs found in 93 %14/15）, and peripheral bone destruction was found in 40 %8/20）, lymph node metastasis was found in 35 %7/20）, 1 case was found with intra-pulmonary metastasis and pleural metastasis respectively, and 1 case with intra-pulmonary and hepatic metastases. Conclusion RMS is a malignant tumor commonly seen in children and adolescent males. It can be diagnosed as having a solid cystic mass in different types of cases. Mild to moderate enhancement in images is commonly found in the lesion with dynamic contrast enhanced images. Certain guiding significance, combining multiple imaging methods can improve the accuracy of diagnosis.