儿童腹部非脏器起源横纹肌肉瘤的临床及影像特征

Clinical and imaging features of abdominal rhabdomyosarcoma of non-organ origin in children

目的探讨儿童腹部非脏器起源横纹肌肉瘤（RMS）的临床及影像学特征。方法回顾性分析12例手术、病理证实的腹部原发非脏器起源的RMS患儿的临床及影像学资料。结果12例患儿中，男9例，女3例，年龄（5.47±3.92）岁。临床分期为Ⅲ期~Ⅳ期，病理分型基本均为胚胎性RMS。肿瘤位于盆腔7例，位于腹腔2例，位于腹膜后1例，横跨腹盆腔1例，跨越腹膜后及腹盆腔1例。肿瘤最大14 cm，最小6 cm。灰阶超声表现为不均匀中等回声，彩色多普勒检查显示肿瘤血流信号丰富。CT平扫呈等低密度，增强后肿瘤不均匀强化，延迟扫描强化更明显，周边强化较中心更为显著。结论儿童腹部非脏器起源的RMS可能起源于腹膜组织，好发于〈10岁的儿童，男孩多见，多位于盆腔，病理分型以胚胎性RMS多见。超声和CT检查有一定的特异性。

ObjectiveTo evaluate the clinical and imaging features of abdominal rhabdomyosarcoma of non-organ origin in children.MethodsWe retrospectively analyzed the clinical and imaging features of 12 pediatric patients with abdominal rhabdomyosarcoma confirmed by surgery and pathology at our hospital.ResultsThere were 9 boys and 3 girls, with an average age of （5.47±3.92） years old （range, 1 to 15）. According to Intergroup Rhabdomyosarcoma Study （IRS） staging system, they were of stage Ⅲ to stage Ⅳ, and most were of embryonal type. Tumors of 7 cases were located in the pelvic cavity, 2 cases in the abdominal cavity, 1 in the retroperitoneal space, 1 in both the abdominal and pelvic cavities and 1 across the retroperitoneal space, and abdominal and pelvic cavities. Gray-scale ultrasound showed moderate inhomogeneous echo structure and color Doppler flow imaging showed rich blood flow signals. CT plain scan showed masses of iso- or low-density, and the contrast-enhanced scan showed lesions with inhomogeneous enhancement. The enhancement in delay scan was more obvious and the peripheral enhancement was more significant than central enhancement.ConclusionsChildhood abdominal rhabdomyosarcoma of non-organ origin may arise from the peritoneum, be commonly seen in boys younger than 10 years old, more likely located in the pelvic cavity, and embryonal rhabdomyosarcoma is the most common histological variant seen in childhood. Ultrasound and CT imaging can provide useful information for diagnosis and differential diagnosis of this tumor.