泌尿系统原发性原始神经外胚层瘤临床病理分析

目的 探讨泌尿系统原发性原始神经外胚层瘤(primitive neuroectodermal tumor,PNET)的临床病理特征、免疫学表型、治疗方法及预后.方法 回顾性分析3例泌尿系统原发性PNET患者资料.3例均为男性,年龄分别为29、32和75岁.2例原发于肾脏,1例原发于膀胱.2例肾肿瘤大小分别为7.7 cm×6.2 cm和12.6 cm×9.4 cm,影像学检查提示肿瘤边界尚清,内部回声欠均匀.膀胱肿瘤大小为10.0 cm×10.0 cm,影像学检查提示膀胱壁不规则增厚,其内密度不均匀.2例肾肿瘤行肿瘤根治术,膀胱肿瘤行血块取出术及肿瘤活检术.结果 光镜下,瘤细胞为形态一致的小圆形或卵圆形,被纤维结缔组织分隔成实性片状或巢状,并形成假菊形团或Homer-Wright菊形团,核分裂象多见.免疫组化标记:3例肿瘤CD99、突触素和波形蛋白均为阳性.1例肾肿瘤Ki67阳性率＜5%,另1例80%阳性.3例病理诊断均为PNET.例1肾肿瘤患者未行化疗,于术后14个月复发死亡;例2肾肿瘤及例3膀胱肿瘤患者术后予以化疗,分别于术后4、6个月死亡.结论泌尿系统原发性PNET是一种少见的高度恶性软组织肿瘤,诊断主要依据病理形态学特征及免疫组化标记.目前治疗方法主要是手术加放、化疗.

Abstract：

Objective To explore the clinico-pathological features, immunophenotype, treatment and prognosis of urologic primary primitive neuroectodermal tumor (PNET). Methods The clinical data of 3 patients with urologic PNET were analyzed retrospectively. All patients were male, aged 29, 32 and 75 years respectively. Two of the lesions were located in the kidney, and the third was located in the bladder. The sizes of renal tumors were 7.7 cm×6.2 cm and 12.6 cm×9.4 cm respectively. Imaging examinations revealed a well-defined mass with inhomogeneous echo inside. The size of bladder tumor was 10.0 cm×10.0 cm. CT scan demonstrated irregular thickening of the bladder wall, and the density of the wall was inhomogeneous. In the 2 cases of renal PNET radical surgery was performed, while an emergency palliative surgery to remove a blood clot and biopsy were performed in the bladder PNET case. Results In light microscope, the tumors were characterized by uniform small round or oval cells and nest-like or dense sheet structures surrounded by sparse fibrovascular stroma. Homer-Wright rosettes or pseudorosettes were observed, as well as mitoses. Immunohistochemical study revealed that all cases showed positive staining for CD99, synaptophysin and vimentin. One of the renal tumor cells showed positive for CD56, and the other renal tumor and urocystic tumor cells were focally positive for chromogranin A. Additionally, in 1 of the cases of renal tumor there was a high positive rate of 80% for Ki67 staining while the other case showed less than 5%. All 3 cases were eventually diagnosed as PNET. The first renal tumor case was not treated with radiotherapy and chemotherapy postoperatively, and the patient died of recurrence 14 months after surgery. Both the second renal tumor case and the bladder tumor case underwent chemotherapy postoperatively, and they died 4 and 6 months after surgery respectively. Conclusions The urologic primary PNET is a very rare, highly malignant soft tissue tumor, and the diagnosis must be based on pathologic findings and immunohistochemical phenotypes. The multimodal treatment for urologic primary PNET consists of surgery, chemotherapy and radiotherapy.

Clinical pathologic analysis of urologic primary primitive neuroectodermal tumor

Objective To explore the clinico-pathological features, immunophenotype, treatment and prognosis of urologic primary primitive neuroectodermal tumor (PNET). Methods The clinical data of 3 patients with urologic PNET were analyzed retrospectively. All patients were male, aged 29, 32 and 75 years respectively. Two of the lesions were located in the kidney, and the third was located in the bladder. The sizes of renal tumors were 7.7 cm×6.2 cm and 12.6 cm×9.4 cm respectively. Imaging examinations revealed a well-defined mass with inhomogeneous echo inside. The size of bladder tumor was 10.0 cm×10.0 cm. CT scan demonstrated irregular thickening of the bladder wall, and the density of the wall was inhomogeneous. In the 2 cases of renal PNET radical surgery was performed, while an emergency palliative surgery to remove a blood clot and biopsy were performed in the bladder PNET case. Results In light microscope, the tumors were characterized by uniform small round or oval cells and nest-like or dense sheet structures surrounded by sparse fibrovascular stroma. Homer-Wright rosettes or pseudorosettes were observed, as well as mitoses. Immunohistochemical study revealed that all cases showed positive staining for CD99, synaptophysin and vimentin. One of the renal tumor cells showed positive for CD56, and the other renal tumor and urocystic tumor cells were focally positive for chromogranin A. Additionally, in 1 of the cases of renal tumor there was a high positive rate of 80% for Ki67 staining while the other case showed less than 5%. All 3 cases were eventually diagnosed as PNET. The first renal tumor case was not treated with radiotherapy and chemotherapy postoperatively, and the patient died of recurrence 14 months after surgery. Both the second renal tumor case and the bladder tumor case underwent chemotherapy postoperatively, and they died 4 and 6 months after surgery respectively. Conclusions The urologic primary PNET is a very rare, highly malignant soft tissue tumor, and the diagnosis must be based on pathologic findings and immunohistochemical phenotypes. The multimodal treatment for urologic primary PNET consists of surgery, chemotherapy and radiotherapy.