肾尤文氏肉瘤/原始神经外胚层肿瘤:1例报道并文献复习

肾尤文氏肉瘤/原始神经外胚层肿瘤(Ewing’s sarcoma/primitive neuroectodermal tumor,EWS/PNET)是一种罕见的肾肿瘤,恶性程度高,好发于儿童和青少年。患者多无特征性临床表现,常以腹痛或肉眼血尿而就诊。EWS/PNET临床进展迅速,易早期出现远隔转移并导致死亡,预后差,因此,及时、准确地做出诊断尤为重要。患者一经确诊,需接受包括根治性手术切除、化学治疗及放射治疗在内的综合治疗。遗憾的是,EWS/PNET在超声声像图及其他影像学检查中并无特异性表现。目前,肾EWS/PNET的诊断主要依靠其典型的组织学特点和免疫组织化学分析结果,特征性染色体异常也可作为有力的诊断依据。免疫组织化学分析CD99强阳性是其基本特征,t(11;22)染色体异位发生于大约90%的EWS/PNET病例中。本文报道了1例右肾EWS/PNET患者,患者为青年女性,以突发右侧腹痛为主要临床表现。超声检查时发现右肾下极可见一大的混合回声包块,对集合系统造成挤压导致肾上极扩张、积水。彩色多普勒检测到肿瘤内部存在动脉样血流频谱。患者接受了右肾肿瘤根治性切除术,并同时行右肾静脉和下腔静脉癌栓切除术。术后影像学检查提示,肿瘤未累及其他组织和器官。患者随后接受了共计6个周期的化学治疗。通过该肿瘤的特征性组织学特点和免疫组织化学结果,最终确诊为EWS/PNET。患者目前随访5年无复发征象。EWS/PNET的声像图表现虽无特异性,但超声检查仍是肿瘤初始评估的主要方法,超声引导下细针穿刺活检也具有重要的术前诊断价值。

Renal Ewing's sarcoma/primitive neuroectodermal tumor: a case report and literature review

Ewing's sarcoma/primitive neuroectodermal tumor (EWS/PNET) in the kidney is a rare but high-grade malignant tumor that affects predominantly elder children and adolescents.Patients mostly present with nonspecific symptoms such as abdominal pain and gross hematuria.Since EWS/PNET has a rapid clinical progression with early metastasis and death,it is essential to make an accurate and early diagnosis.Once diagnosed,multimodality treatment,including radical surgery combined with adjuvant chemotherapy,and radiotherapy if necessary,is recommended.Unfortunately,there are no characteristic signsthat have been described in ultrasonography or any other imaging modalities so far.The diagnosis of EWS/PNET is now based on a classical histological and immunohistochemical investigation complemented by a demonstration of specific chromosomal changes.Strong immunoreactivity to CD99 is ubiquitous,and t(11;22) translocation is seen in approximately 90％ of EWS/PNET.Herein,we report a patient with such condition.The patient was a young woman,and she presented with sudden right flank pain clinically.Ultrasonography revealed a large heterogeneous mass in the lower pole of her right kidney.The tumor compressed the renal pelvis and led to upper pole caliectasis.Color Doppler demonstrated blood flow with a pulsatile arterialized waveform within the mass.The patient received radical nephrectomy with right renal vein and vena cava thrombectomy.A search for other sites of tumor involvement yielded negative results.And six cycles of chemotherapy were sequentially performed.The diagnosis of EWS/PNET was confirmed based on primitive small round cell histology and characteristic immunohistochemical results.She was still alive with no evidence of recurrence five years after initial diagnosis.We would like to point out that ultrasound is still a useful method for initial assessment,and ultrasound-guided fine needle aspiration may play an important role in determining preoperative diagnosis.