Primitive neuroectodermal tumors

The primitive neuroectodermal tumors (PNETs) of Hart and Earle constitute an important fraction of pediatric brain tumors that are clinically characterized by their aggressive behavior. In 1983, Rorke expanded the term “PNET” to include all small cell embryonal neoplasms of neuroectodermal origin, regardless of the location of the tumor. More recently, Dehner also proposed the terms “central” and “peripheral” PNETs, and the provocative concept of “PNET” has now come to encompass a diverse group of tumors in both the central and peripheral nervous systems. The acronym “PNET” has thus become a confusing and controversial term in the diagnosis and classification of pediatric embryonal tumors. We reviewed ten papers concerning the various aspects of PNETs.     

Primitive neuroectodermal tumor of the kidney: A rare entity

Primitive neuroectodermal tumor (PNET) is usually aggressive and rapidlyprogressing and metastasizing tumor. Occurrence of the this type of tumorin the kidney is considered as unusual, and few cases have been reportedso far. We present a PNET arising from the kidney in a 23-year-old femalepatient.     

卵巢原始神经外胚层肿瘤1例

正患者女,26岁,1个月前无明显诱因出现恶心、呕吐及频繁嗳气,呕吐物为胃内容物,伴下腹胀、尿频、便秘。近半个月出现间断下腹坠痛3次,每次持续约1h。生命体征平稳,体质量减轻20余斤。体格检查:盆腔可触及实性包块,上界达脐部,有轻压痛。血清肿瘤标记物:CA125 258.10 U/ml,CEA、CA199、AFP正常。MR检查:子宫上方见大小约17.7cm×10.4cm×14.6cm肿块,T1WI呈等及稍低信号,T2WI呈大部     

输尿管原始神经外胚叶肿瘤1例

正患者女,44岁,因"无痛性肉眼血尿3个月"入院。专科查体未见明显异常。尿常规红细胞计数1 184/μl(参考范围0～10/μl)。超声:右侧输尿管膀胱壁内段增粗呈稍低回声,直径约0.8cm,边界清晰,于膀胱三角区呈结节状凸入膀胱,右侧输尿管稍扩张;CDFI示病变内血流信号丰富。MRI:右侧输尿管壁内段壁增厚,末端呈结节状凸入膀胱,约0.9cm×1.5cm,右侧输尿管稍扩张,直径约0.9cm;T2-频率选择反转恢复衰减序列(spectral attenuated inversion recovery,SPAIR)图像示病变呈     

外周性原始神经外胚层瘤一例

正患者女,20岁,因发现颈项部无痛性肿物3年入院。患者于3年前无意中发现未予重视,近半年自觉肿物迅速增大来诊。查体:心、肺、腹部未见明显异常,颈软,皮肤色泽正常,无湿疹、溃疡、瘘管,气管居中。颈项部偏右侧可见5.0 cm×6.0 cm×4.0 cm大小肿物,质韧,边界清楚,表面无红肿破溃,活动度尚可,颈部未触及肿大淋巴结。入院后完善化验及检查未见明显异常,超声检查提示:后颈部距皮下0.4 cm可见范围约4.9 cm×5.2 cm×3.3 cm低回声团,边界尚清晰,形态欠规整,内回声不均匀,CDFI示其内及周边可见血流信号。于2017年9月21日在局麻下行颈部肿物切除术,术中见肿物无明显边界,伴胶冻状液体流出,快速冰冻提示恶性肿     

Papillary cystic neoplasm of the pancreas: report of two cases of a surgically curable tumor

This is a report of two cases of papillary cystic neoplasm of the pancreas, a recently described, relatively benign tumor of the pancreas that occurs predominantly in young women. The clinical presentation, radiographic features, and gross and microscopic pathologic findings along with immunohistochemical and electron microscopic studies are described. A brief review of the literature is cited and surgical significance is discussed.     

Epidermoid tumors of the 4th ventricle: report of seven cases

Epidermoid tumors occur very rarely in the 4th ventricle. We discuss the history, clinical course, and the surgical results for seven patients. One patient had a remittal of symptoms, probably due to the emergence of the tumor from the 4th ventricle into the cisterna magna. Total removal of the capsule was possible only in the youngest patient. At present, four patients (mean follow-up, 6 years) enjoy good general and neurological health.     

Central pancreatectomy for neoplasm of mid pancreas — a report of four cases

Central pancreatectomy (CP) originally done for pancreatic trauma and focal pancreatitis is recently being performed for benign and low grade malignant neoplasm of mid pancreas. It offers the advantage of conserving pancreatic tissue and preserving gastroduodenal-biliary anatomy, important for maintenance of endocrine and exocrine pancreatic function. We reviewed our database between Jan. 2005 and June 2007. Four patients (2 males and 2 females) in the age range of 12 to 55 years underwent CP for a mass in the mid pancreas. Two were known diabetic. Histology reported solid variant of serous cystadenoma (1), solid pseudopapillary tumor (1), focal pancreatitis (1) and ductal adenocarcinoma (1). Postoperatively one patient had transient pancreatic fistula which was managed conservatively. There was no mortality. On follow-up (7 to 43 months) none of the patients required enzyme supplements and diabetes did not worsen. Patient with ductal adenocarcinoma progressed within 7 months. CP may be a viable option for mid pancreatic lesions of benign or low grade malignant potential.     

Solid pseudopapillary tumour of pancreas: A rare neoplasm

Solid pseudopapillary tumour (SPT) is the rare tumour of pancreas with unknown aetiology and good prognosis. Occurs predominantly in young women of reproductive age group. Not many cases have been reported from India. We report a case of a young woman who presented with persistent back pain having large tumour of body of pancreas treated successfully by left pancreatectomy.     

Metastases from carcinomas of the pancreas simulating primary mucinous tumors of the ovary. A report of seven cases

We report seven patients with mucinous tumors of the ovary that we interpreted as metastases from adenocarcinomas of the exocrine pancreas. The ovarian metastases closely resembled primary mucinous tumors of the ovary. The patients' ages ranged from 29 to 87 years (average, 63 years). The ovarian and pancreatic tumors were discovered synchronously in five patients. In two patients, the pancreatic tumor preceded the ovarian tumor by 9 months and 8.5 years, respectively. In four patients, the clinical presentation simulated primary ovarian cancer. The ovarian tumors were typically large, multiloculated cystic neoplasms. Six of them were bilateral; the status of the opposite ovary is not known in one case. Microscopically, they manifested varying degrees of differentiation, usually containing foci resembling mucinous cystadenoma, mucinous tumor of borderline malignancy, and well-differentiated mucinous cystadenocarcinoma. The primary pancreatic tumors were typical ductal adenocarcinomas in six patients and mucinous cystadenocarcinoma in the seventh. Features pointing toward the metastatic nature of the ovarian tumors included bilaterality, surface desmoplastic implants, and extraovarian spread. The possibility of metastases should be strongly considered whenever evaluating mucinous ovarian tumors, especially those that are bilateral or have other unusual features. The pancreas is an important source of metastatic tumors that simulate primary ovarian mucinous cystadenocarcinomas and borderline tumors.     

Primitive neuroectodermal tumors of childhood. An approach to therapy

Primitive neuroectodermal tumors are found in the cerebrum of children and young adults. The are clinically highly malignant and have rapid course from diagnosis to death. Their microscopic pathology reveals 90% to 95% nondifferentiation, frequent mitoses, and small dark cells with no observable cytoplasm. This paper discusses the treatment of three children with this tumor with a combination of surgery irradiation, and combination chemotherapy. The results of this approach are compared with previous reports in the literature. The average survival in this series is 24 months versus approximately 8 months reported in the literature.     

Primitive neuroectodermal tumor of the thumb metacarpal bone: a case report and literature review

A 27-year-old otherwise healthy patient was diagnosed with a primitive neuroectodermal tumor of the thumb metacarpal bone of the left hand. Based on a common chromosomal translocation this tumor shows a close relationship to Ewing's sarcoma. Its occurrence in the extremities is uncommon and involvement of the hand is extremely rare. The treatment consisted of neo- and adjuvant chemotherapy and marginal resection of the affected thumb metacarpal bone including periosseous soft tissue and reconstruction of the thumb by an intercalated segmental index pollicization.     

Peripheral primitive neuroectodermal tumors arising in the pancreas: the first case report in Asia and a review of the 14 total reported cases in the world

Objective

To discuss the diagnosis and treatment of peripheral primitive neuroectodermal tumors of the pancreas based on our case and all the cases in the world.

Methods

The first case of peripheral primitive neuroectodermal tumors of the pancreas in Asia was preliminarily reported by our group in 2006. The patient underwent three operations for the primary tumor and recurrences over 41 months prior to the patient’s death in November 2007. All 14 reported cases of pancreatic PNETs in the world were analyzed. The corresponding literatures on its diagnosis and treatment of were reviewed.

Results

A 13 year-old female patient was diagnosed with pancreatic PNETs by the clinical, microscopic, immunohistochemical features, and cytogenetic analysis after the resection of the tumor located in the uncinate process of the pancreas at PUMC Hospital. During the follow-up course, radiotherapy and chemotherapy were given after the first operation. Two additional operations were performed 10 months and 25 months after the first one, respectively, because of tumor recurrence. The patient died 41 months after the initial diagnosis with the recurrence and metastasis that were not suitable for a further surgery. Primitive neuroectodermal tumors of the pancreas are extremely rare. A review of the world’s literature on this tumor identified fourteen cases with a mean survival time of 12 months (ranging from 6 to 50 months). These patients often have no specific clinical symptoms, but most do present with abdominal pain and/or jaundice. The diagnosis is established by small round tumor cells seen on light microscopy, immunohistochemical features of positive P30/32^MIC2 with at least two positive neuronal markers., and cytogenetic analysis showing characteristic translocation of t[11;22][q24;q12]. Since pancreatic PNETs are highly aggressive, early diagnosis, immediate surgical resection and re-resection if possible, early radiotherapy and chemotherapy and close follow-up are required.

Conclusions

Peripheral primitive neuroectodermal tumors can arise in pancreas. The diagnosis and treatment should be made as early as possible, aggressive surgeries for the primary and recurrences may help to improve the prognosis.Key Words: Peripheral primitive neuroectodermal tumors, pancreatic tumor, small round cell tumors, Ewing’s sarcoma     

Synchronous solid pseudopapillary neoplasm and intraductal papillary mucinous neoplasm of the pancreas: report of a case

Solid pseudopapillary neoplasm (SPN) of the pancreas, most commonly found in young female subjects, is a rare neoplasm with low potential for malignancy. We report an unusual case of a 66-year-old male patient who had a simultaneous malignant SPN and an intraductal papillary mucinous adenoma (IPMA) of the pancreas. The patient was admitted to our department for the evaluation of the main solid tumor with calcification and small multilocular cystic lesions apart from the main tumor in the pancreatic head. We performed pylorus-preserving pancreaticoduodenectomy to treat the calcified tumor and multilocular cystic lesions. The diagnosis of malignant SPN was confirmed on the basis of histological invasion to the adjacent structures. The separate cystic lesions were diagnosed as a branch-type IPMA. The synchronous occurrence of IPMA and SPN in the present case did not demonstrate that there were tumors maintained through the common abnormal Wnt signaling pathway by immunohistochemical study. To our knowledge, this is the first known case of synchronous SPN and IPMA of the pancreas.