CT、MRI检查在外周原始神经外胚层肿瘤诊治中的作用

目的：通过对影像学和病理学的分析，旨在提高对外周神经外胚层肿瘤(pPNET)的认识。方法：回顾性分析有完整影像和病理资料的6例pPNET。结果：软组织pPNET的CT表现为大的、边界不清的软组织肿块，密度不均匀伴坏死囊变，不伴钙化，增强后呈不均匀强化。骨pPNET主要表现为较大的溶骨性骨质破坏伴软组织肿块，无新生骨、瘤骨，增强后不均匀强化。MRI在SE序列T1W表现为等肌肉信号，T2W表现为不均匀高信号，增强后强化不均匀，可见类似包膜和分隔样改变。结论：pPNET的影像学表现没有明显特征性。CT和MRI的作用主要用于描述肿瘤内部结构、侵犯范围以及与周围组织、血管神经的关系，同时可以提供肿瘤远处转移的信息，对临床手术可切除性与评价疗效有着非常重要的意义。     

Chemotherapy for medulloblastomas and primitive neuroectodermal tumors

Summary In the past two decades, chemotherapy has proven to be an increasingly more effective modality in the treatment of medulloblastoma. Current evidence suggests that chemotherapy be included as part of standard treatment for all patients with high-risk medulloblastoma. Ongoing multi-centre trials are determining whether chemotherapy should be added to reduced dose radiotherapy as a substitute therapy for standard-dose radiotherapy. The major randomized and non-randomized chemotherapy trials for newly diagnosed patients with medulloblastoma or for patients at recurrence are presented. It is hoped that the addition of chemotherapy will eventually lead to improved survival rates as well as the reduction in the craniospinal radiotherapy dose for patients with medulloblastoma.     

外周性原始神经外胚层肿瘤的诊断及治疗

目的：探讨外周性原始神经外胚层肿瘤（peripheral primitive neuroectodermal tumors,pPNETs）的诊断及治疗。方法：回顾性分析我院收治的5例经病理证实的 pPNETs 患者的诊治过程,并复习文献。结果：本组病例均为软组织,1例位于颈部,1例位于肩部,1例位于腋窝,2例位于胸壁。CT 平扫显示肿物多呈不均匀的等、低密度,所有肿瘤增强后均可见不均匀强化。3例患者行 MRI,显示 T1WI 呈与肌肉类似的混杂信号, T2WI 表现为不均匀的高信号。2例患者行 B 超检查,显示肿物局部低密度影,内可见血流信号,未压迫周围血管。镜下可见肿瘤细胞形成典型的 Homer －Wright 菊形团。免疫组化显示肿瘤均表达 CD99和 VIM,NSE和 Syn 多数阳性,CK 阴性,并且不表达 LCA,部分低表达 S100。结论：pPNETs 是一种少见的小圆细胞恶性肿瘤。CT 及 MRI 检查可评估肿瘤可切除性。B 超可了解肿物的血供及与周围血管的位置关系。pPNETs 的确诊依靠病理及免疫组化,尤其是 Homer －Wright 菊形团及神经内分泌标记物对肿瘤的确诊有重要意义。手术是直接有效的治疗手段,术前新辅助化疗可以减少 pPNETs 局部淋巴结转移。     

Primary peripheral primitive neuroectodermal tumors of the spinal cord: report of two cases and review of the literature

Primary intraspinal peripheral primitive neuroectodermal tumors (pPNETs) are extremely rare tumors with only seven reported cases in the literature. The histopathologic diagnosis of this tumor is complex and has led to a variety of treatment approaches. The distinction between central and peripheral type primary spinal cord PNETs has not always been made in the literature, leading to a paucity of data in this disease. We present here two young patients with primary intraspinal pPNET, their treatment and outcome. The first patient, a 27 year old male, presented with an intradural mass extending from L2 through L5, after multiple relapses, he is currently alive with disease after 72 months, the longest survival yet reported. The second patient, a 16 year old female, presented with an intradural mass at the cauda equina from L2 through L5, and is currently alive with responsive disease at 5 months after initial diagnosis. Here, we discuss the clinical course, the pathology and treatment for this disease and review the literature.     

Adult primary pulmonary primitive neuroectodermal tumor: Molecular features and translational opportunities

Primitive neuroectodermal tumors (PNET) arising directly from the lung are very rare but particularly aggressive neoplasms. We report a case of a 31-y-old man with primary pulmonary neuroectodermal tumor. We review the clinical as well as pathological features. As typical for these tumors, the diagnosis was initially delayed in our patient and prognosis was poor despite aggressive surgical resection, postoperative chemotherapy and local irradiation. Recent biological insights have revealed unique chromosomal translocations crucial to the pathogenesis of these tumors, most notably the EWS-FLI-1 translocation. We provide an overview of the molecular features of the Ewing Sarcoma Family of Tumors (ESFT) including PNET and their potential implications for therapeutic targeting.     

Cerebral primitive neuroectodermal tumors in childhood

A series of 17 infants and children with cerebral primitive neuroectodermal tumors (PNETs) detected by computed tomography is presented. The pertinent literature is reviewed. Because of ongoing nosological difficulty, we include in this series only those tumors which are located in the cerebral hemisphere, and are composed of predominantly undifferentiated neuroepithelial tumor with or without glial or neuronal differentiation. The prognosis of the patients with cerebral PNETs remains poor despite treatment including surgical resection, radiation therapy and/or chemotherapy. Only two patients had a long term survival more than 4 years in this series. The histological features and the extent of surgical resection did not influence the patients survival. Nevertheless, visible total resection afforded better control of local disease of the primary site, but remote metastases along the cerebrospinal fluid pathway were frequent at relapse. The patients with crebral PNETs appear to be best treated with radical gross total resection, postoperative radiation therapy including irradiation to the neuraxis and aggressive chemotherapy.     

外周性原始神经外胚层瘤的临床病理及免疫组织化学特征

目的:探讨外周性原始神经外胚层瘤(peripheral primitive neuroectodrmaltumour,pPNET)的临床病理及免疫组织化学特征。方法:对8例pPNET进行组织形态学观察和组化及免疫组化染色,并复习病史。结果:8例pPNET患者临床表现为进行性增大的局部肿块及其继发症状。影像学检查显示病变为密度增高的软组织影或溶骨性骨组织破坏。光镜下,瘤细胞为形态均一的小圆形或卵圆形,被纤维结缔组织所分隔成实性片状或巢状。部分病例可见典型Homer-Wright菊形团及/或菊形团排列趋势,1例伴明显神经细胞分化。免疫组化:8例pPNET中,CD99、Syn和NSE 3种标记阳性率较高,分别为7/8、6/8及7/8,Vim和CgA分别为5/8。Syn和NSE 2项阳性6例,CD99和Syn或NSE 2项阳性7例,3项均阳性6例。结论:pPNET是一种好发于青少年、形态原始和少见的高度恶性肿瘤,CD99、NSE及Syn的联合表达有助于pPNET的诊断和鉴别诊断。     

Supratentorial primitive neuroectodermal tumors: a Canadian pediatric brain tumor consortium report

Introduction Supratentorial primitive neuroectodermal tumors (SPNET) are rare tumors accounting for only 2.5% of childhood brain tumors. The purpose of this study was to describe the range of treatment regimens used to treat pediatric SPNET in Canada and to identify prognostic factors for overall survival in this population. Methods This study was a retrospective clinical analysis of SPNET patients treated over the last 10 years in Canada. A questionnaire was developed and distributed to all institutions in Canada who treat pediatric patients. Data were collected for patients <19 years of age who were diagnosed and treated for SPNET between 1995 and 2005. Results Data were obtained for 48 eligible patients. The stages of patients for whom complete data were provided were 80, 3, and 16% for metastatic stage M0, M1, and M2/3, respectively. The best responses to therapy included complete response in 44%, partial response in 8%, still on therapy in 2%, progressive disease in 31%, toxic death in 2%, and no therapy given in 12%. The 4-year survival was 37.7 ± 7.6%. The factors associated with an increase in survival were the use of radiation therapy and chemotherapy, and age >2 years. Overall survival was not affected by metastatic disease at diagnosis, tumor site, or degree of initial resection. Conclusions Survival is poor in SPNET patients but highest in those who received chemotherapy and radiation therapy. Further studies are needed to improve the survival of these patients.     

血尿表现的前列腺原始神经外胚层瘤1例并文献复习

目的:探讨前列腺原始神经外胚层瘤临床表现、病理学特点、诊断标准及治疗与预后,以提高对本病的诊疗水平。方法:回顾性分析我院前列腺原始神经外胚层瘤1例及总结文献检索所得前列腺PNET病例12例的临床表现、病理结果及治疗与预后。结果:病例中最短生存期为术后一个月死于肺转移。最长生存期为随访至12个月。我院病例术后4月复查盆腔肿瘤复发。结论:外周PNET十分罕见,前列腺PNET更罕见。对于排尿困难和血尿的青年患者如诊断不明确应考虑本病可能。超声、CT、MRI可发现该疾病但无特异性,病理可诊断。早期诊断、积极治疗对预后影响大,对于晚期患者化疗效果明显。     

儿童原始神经外胚叶肿瘤的临床特征(附4例临床报告及文献复习)

目的 探讨儿童大脑神经外胚叶肿瘤的临床特点及治疗方法。方法 对我院1999年1月至2003年1月收治的4例小儿大脑神经外胚叶肿瘤的临床资料进行回顾性分析。结果 4例病人1例位于额叶，2例位于顶叶，1例位于颞叶。OT显示为高或等密度影，MRI为短TI长T2信号，增强后均匀强化，肿瘤有明显界线。4例均在显微镜下全切，病理诊断：原始神经外胚叶肿瘤。术后均行放疗。术后8个月～18个月复发。结论 小儿大脑原始神经外胚叶肿瘤为高度恶性的肿瘤，预后差手术加放疗能延长生存时间。     

Ewing sarcoma/primitive neuroectodermal tumor of the ureter:A case report and literature review

Ewing sarcoma/primary neuroectodermal tumors are rare,invasive,and small round blue cell tumors.There are few reports of its occurrence in the urinary system.Here,we present the first middle-aged female patient whose Ewing sarcoma primary site was in the ureter.The main clinical manifestation was intermittent hematuria.She was in good health after complete surgical resection and adjuvant radiotherapy.To date,there has been no recurrence or metastasis.Accurate early diagnosis and appropriate treatment can help prolong survival.18F-fluorodeoxyglucose positron emission tomography/computed tomography is expected to be an effective means of evaluating treatment effects and detecting metastasis and recurrence.In this article,besides introducing a case of Ewing sarcoma/primitive neuroectodermal tumor of the ureter,we review the literature to discuss the current status of diagnosis and treatment.     

High-dose chemotherapy with autologous stem cell rescue for children with high risk and recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors

Current treatment for high risk and recurrent medulloblastoma (MB) and supratentorial primitive neuroectodermal tumors (stPNET) has a very poor prognosis in children. High dose chemotherapy (HDCT) and autologous stem cell rescue have improved survival rates. We present 19 patients (thirteen classified in the high risk group and six patients with recurrent disease) that received HDCT and autologous stem cell rescue.In the high risk group [Med Pediatr Oncol 38 (2002) 83], all patients underwent neurosurgical debulking. Standard chemotherapy was prescribed in 10 patients. Radiotherapy was given to 4 patients (all older than 4years old). In the recurrence disease group [Childs Nerv Syst 15 (1999) 498], five patients underwent surgery. Radiotherapy was given to those who were not previously irradiated. The HDCT in twelve patients consisted of busulfan 4mg/kg/day, orally over 4days in 6-hourly divided doses and melphalan at a dose of 140mg/m²/day by intravenous infusion over 5min on day –1. Three patients additionally received thiotepa 250mg/m²/day intravenously over 2days and four patients additionally received topotecan 2mg/m²/day over 5days by intravenous infusion over 30min. The other seven patients received busulfan and thiotepa at the same doses.Patients stem cells were mobilized with granulocyte colony-stimulating factor at a dose of 12g/kg twice daily subcutaneously for four consecutive days. Cryopreserved peripheral blood progenitor cells were re-infused 48h after completion of chemotherapy. With a median follow-up of 34months (range 5–93) eight complete responses and one partial response were observed. Three patients died of treatment-related toxicities (15%). The 2 year event-free survival was 37.67±14% in all patients and 57±15% for the high risk group.Therefore we conclude that HDCT may improve survival rates in patients with high risk/recurrent MB and stPNET despite treatment toxicity.     

Cerebral primitive neuroectodermal tumor in an adult,with spinal cord metastasis after 18-year dormancy

A cerebral primitive neuroectodermal tumor in a 40-year-old man recurred as a metastasis to the spinal cord after an 18-year dormant period. The metastatic tumor showed features of neuronal differentiation. The clinical course and pathologic findings are discussed.     

原始神经外胚层肿瘤化疗相关因素的研究

目的评价原始神经外胚层肿瘤患者化疗的客观疗效,分析影响预后的因素。方法总结2000年3月～2008年9月我院收治的23例接受化疗的原始神经外胚层肿瘤患者的临床特点及化疗效果,用COX生存模型回顾性分析年龄、性别、是否手术、是否放疗、是否有远处转移、CD99的表达强度及是否接受新辅助化疗对其生存预后的影响。结果23例患者中女性11例,男性12例,中位年龄27岁,化疗后CR0例,PR11例,客观有效率55％,有效率与CD99表达强度不相关（P=0．843）,中位生存期为12个月。年龄（P=0．024）、远处转移（P=0．032）和放疗（P=0．044）对死亡风险有显著性影响,CD99表达强度在模型中P值为0．067。结论本组研究中原始神经外胚层肿瘤患者男女比例相当,多为年轻患者,化疗有效率较高,但生存期不长。接受放疗、年龄小、无远处转移、CD99表达强度低的患者死亡的风险小,CD99表达强度越高死亡的风险越大。     

原始神经外胚层瘤的诊断和治疗

原始神经外胚层瘤是一类好发于儿童及青少年的高度恶性肿瘤,发病率呈上升趋势,其早期诊断率较低,治疗效果欠佳。随着逆转录PCR、荧光原位杂交技术等分子生物学技术应用于病理诊断领域,磁共振、正电子发射型计算机断层显像(PET) -CT等应用于影像学诊断领域;靶向治疗、多学科综合治疗理念在治疗中的贯彻,原始神经外胚层瘤的发病机...     

Cytogenetic and histopathologic studies of congenital supratentorial primitive neuroectodermal tumors: A case report

Primitive neuroectodermal tumors (PNET) represent about 25% of primary central nervous system tumors in childhood, but congenital PNETs are rare. Cytogenetic studies and studies on molecular pathology have identified several genetic alterations in medulloblastoma, but molecular investigations on supratentorial PNETs are infrequent. We present a male newborn with a large congenital PNET of the right cerebral hemisphere and the molecular analysis of the tumor. Tumor tissue was investigated by routine histology and immunohistochemistry. Fluorescence in-situ hybridization was carried out on native tumor tissue to investigate deletions on chromosome 17p and to analyze c-Myc or N-Myc amplifications. Histologic examination revealed a primitive neuroectodermal tumor with massive extension covering almost the entire right hemisphere. Genetic analysis of the native tumor tissue of our patient excluded a deletion of chromosome 17p. An amplification of the c-Myc or N-Myc oncogene was absent using fluorescence in-situ hybridization. Despite unremarkable genetic analysis in our case prognosis was poor, suggesting that there are additional, yet unknown constitutional genetic aberrations in the pathogenesis of congenital supratentorial PNET.     

Melanotic primitive neuroectodermal (neuroepithelial) tumor of medulla

A 69-year-old man had a melanotic primitive neuroectodermal tumor of the medulla displaying various neuroepithelial elements including undifferentiated neuroepithelial cells forming Homer Wright's rosettes as well as neoplastic neuroglia resembling those seen in medulloblastoma. The neuroglial tumor cells were verified by demonstrating glial fibrillary acidic protein (GFAP) in the cells. These findings support the concept that the primitive neuroectodermal tumor and medulloblastoma are similar neoplasms. They have been described by such diverse names as melanotic medulloblastomas and progonomas. Review of 18 reported cases of intracranial melanotic primitive neuroectodermal tumors, including the present one, reveals that they have common pathologic features, are most frequent in the cerebellum and fourth ventricle, often metastasize widely within the neuraxis or even systemically, occur more frequently in children than adults, and strike males more often than females.     

椎管内原始神经外胚层肿瘤1例

原始神经外胚层肿瘤(primitive neuroectodermal tumor,PNET)临床少见,临床及影像学表现无特异性,极易误诊误治,为提高对本病的认识,我科近来收治1例,报道如下并结合文献复习. 1临床资料 患者,女,20岁.于1.5个月前无明显诱因出现双下肢酸软感,以右侧为甚,双下肢活动正常.当时未予注意,未行检查.近1个月来上述症状加重,出现右脚跛行,自觉右下肢无力伴双下肢麻木感,并出现腰背部疼痛,疼痛呈持续性,有针刺感,无放射他处,活动后加重.曾在我院门诊行腰部X线片检查未发现异常.     

外周型原始神经外胚层肿瘤的CT和MRI影像学表现

目的 探讨外周型原始神经外胚层肿瘤(pPNETs)的CT和MRI表现,以提高pPNETs诊断的准确性.方法 9例经手术病理证实的pPNETs患者中,4例术前经螺旋CT或多排螺旋CT平扫或增强扫描;6例经自旋回波T1WI、快速自旋回波T2WI和屏气扰相梯度回波T1WI 3个序列平扫,动态增强采用屏气快速多层面扰相位梯度重聚成像T1WI快速扫描序列.将CT和MRI表现与手术病理结果进行对照分析.结果 pPNETs位于肌肉6例,盆腔2例,胸腔1例.肿瘤呈椭圆形4例,不规则形5例.肿瘤直径7.4～18.3 cm,平均11.6 cm,境界不清.2例病灶信号和密度均匀,无明显坏死和囊变;7例病灶有明显的坏死和囊变,其中位于胸腔和盆腔的3例肿瘤均可见显著坏死和囊变.CT平扫肿瘤密度与邻近肌肉相仿,增强扫描呈中等程度以上的强化,双期增强呈进行性持续强化,强化不均匀.MRI T1WI序列肿瘤实体成分呈不均匀等信号或略低信号,T2WI呈不均匀略高信号或高信号,MRI增强强化程度较CT强化显著,强化更不均匀.位于肌肉的6个病灶均位于神经路径,可见明显软组织肿块包绕骨骼,3例骨骼破坏轻微,2例骨骼破坏明显,直径与软组织肿块相仿,1例骨骼破坏直径超过软组织肿块.骨质破坏位于骨髓腔,为溶骨性骨质破坏,无肿瘤成骨,无明显骨膜反应.结论 pPNETs多见于儿童或青少年,多位于四肢、躯干的神经路径上,肿瘤体积较大,边缘不规则,境界很不清楚,强化显著且不均匀;位于胸、腹、盆腔的肿瘤坏死和囊变显著,位于四肢的肿瘤包绕骨骼,或坏死和囊变,或密度、信号相对均匀.pPNETs不仅具有神经源性肿瘤坏死和囊变及明显强化的特征,还具有小细胞恶性肿瘤浸润生长的特征.