• Ewing sarcoma
• metastasis
• pancreas
• primitive neuroectodermal tumor

• pPNET
• peripheral primitive neuro-ectodermal tumor
• ulnar nerve

• liver tumor
• peripheral primtive neuroectodermal tumor
• pnet
• ppnet
• primitive neuroectodermal tumor

• ewing sarcoma
• influencing factor
• peripheral primitive neuroectodermal neoplasms
• primitive neuroectodermal tumor
• prognosis
• survival
• therapy

• Humans
• Neoplasms, Germ Cell and Embryonal
• Neuroectodermal Tumors, Primitive/therapy
• Neuroectodermal Tumors, Primitive, Peripheral
• Prognosis
• Retrospective Studies
• Sarcoma, Ewing/pathology

• Ewing sarcoma
• Focal hepatic lesion
• Primitive neuroectodermal tumor

The insulin and insulin-like growth factor-1 (IGF-1) receptors are important for the growth and development of embryonic tissues. To directly define their roles in the maintenance of pluripotency and differentiation of stem cells, we knocked out both receptors in induced pluripotent stem cells (iPSCs). iPSCs lacking both insulin and IGF-1 receptors (double knockout, DKO) exhibited preserved pluripotency potential despite decreased expression of transcription factors Lin28a and Tbx3 compared to control iPSCs. While embryoid body and teratoma assays revealed an intact ability of DKO iPSCs to form all three germ layers, the latter were composed of primitive neuroectodermal tumor-like cells in the DKO group. RNA-seq analyses of control vs DKO iPSCs revealed differential regulation of pluripotency, developmental, E2F1, and apoptosis pathways. Signaling analyses pointed to downregulation of the AKT/mTOR pathway and upregulation of the STAT3 pathway in DKO iPSCs in the basal state and following stimulation with insulin/IGF-1. Directed differentiation toward the three lineages was dysregulated in DKO iPSCs, with significant downregulation of key markers (Cebpα, Fas, Pparγ, and Fsp27) in adipocytes and transcription factors (Ngn3, Isl1, Pax6, and Neurod1) in pancreatic endocrine progenitors. Furthermore, differentiated pancreatic endocrine progenitor cells from DKO iPSCs showed increased apoptosis. We conclude that insulin and insulin-like growth factor-1 receptors are indispensable for normal lineage development and perturbations in the function and signaling of these receptors leads to upregulation of alternative compensatory pathways to maintain pluripotency.

•

Insulin and IGF-1 receptor signaling regulate the expression of pluripotency genes Lin28 and Tbx3.

• Apoptosis
• Insulin/IGF-1 receptors
• Lineage development
• Pluripotency
• Signaling

• Neuroectodermal tumours
• diagnosis
• hospital
• male

• PNET
• incidence
• outcome
• primitive neuroectodermal tumor
• treatment

Peripheral Primitive NeuroEctodermal Tumors (pPNETs) are rare highly malignant tumors; originating from the neuroectoderm. Although PNETs may arise in various locations (most commonly in the extremities), very few cases have been reported in the pelvis. There is still poor evidence about the management of these tumors in the literature.

We present a rare case of pelvic PNET in a 20-year-old male. The patient presented with symptoms mimicking a lumbar disk hernia, which delayed the diagnosis. He was managed with a combination of a debulking procedure, adjuvant chemotherapy, radiotherapy; and has been in remission for 2 years upon follow-up.

This case highlights the importance of diagnosing such aggressive tumors as early as possible (as prognosis may vary significantly), and the challenge in the management of PNETs due to poor evidence.

•

Primitive NeuroEctodermal Tumors (PNET) are highly malignant tumors that generally manifest in the extremities.

• Case report
• ES, Ewing Sarcoma
• PNET, Primitive NeuroEctodermal Tumors
• Primitive neuroectodermal tumors
• Surgical oncology
• pPNET, Peripheral Primitive NeuroEctodermal Tumors

• Double barrel sigmoidostomy
• Primitive neuroectodermal tumor
• Prostate
• Total pelvic exenteration

Primitive neuroectodermal tumors (PNET, previously referred to as peripheral neuroepithelioma) are rare malignant tumors with various degrees of differentiation belonging to the Ewing’s family of sarcomas. They are classified as round cell tumors arising from soft tissues. In rare instances, PNETs may arise from solid organs containing neuroendocrine cells of kidney, bladder, heart, lungs, parotid glands and pancreas. Most cases occur in the second decade of life with a slight preponderance in males. PNET of the pancreas is an aggressive tumor with multiple recurrences and a relatively poor prognosis. These tumors should be considered in the differential diagnosis, especially in a diagnosed pancreatic tumor in individuals less than 35 years of age. Due to the nature of the tumor, surgery with subsequent chemoradiation are widely accepted modalities despite the poor prognosis. In this article, we review 25 cases of extraosseous Ewing’s sarcoma (ES) of the pancreas which to the best of our knowledge, enlists most cases reported in the literature thus far. 

• ewing’s sarcoma
• extraosseous
• pancreas
• primitive neuroectodermal tumor

• neuroectodermal tumors
• peripheral
• primitive
• prognostic factors

Adrenal primitive neuroectodermal tumor (PNET) is an extremely rare malignant tumor with poor prognosis and of neural crest origin. Herein, we report a case of adrenal PNET and summarized its clinical and pathological characteristics on the basis of 16 patients reported recently.

A female patient aged 25 years presented with right lumbago for 12 mo, and pre-operative computed tomography showed a huge right adrenal mass. She received tumorectomy, and post-operative pathological examination showed adrenal PNET. After surgery, she underwent adjuvant chemotherapy and was followed up 31 mo after surgery. She received brachytherapy for right paracolic and hepatic metastases. She was alive and followed up for 60 mo. In available studies, only 57.14% (4/7) and 44.44% (4/9) were positive for the expression of neuron-specific enolase and synaptophysin, respectively, although CD99 expression was found in all the patients (100%; 10/10).

It is concluded that adrenal PNET is very rare and highly malignant, and histology is a golden standard in its diagnosis. Surgery and adjuvant therapy is the main treatment.

• Primitive neuroectodermal tumor
• Adrenal gland
• Case report

• Primitive neuroectodermal tumor
• Sarcoma
• Scrotum

To characterize the imaging and clinicopathological features of primitive neuroectodermal tumors (PNETs) arising in intra-abdominal and retroperitoneal regions.

Eighteen patients with histopathologically proven intra-abdominal and retroperitoneal PNET were enrolled; computed tomography was performed for all cases, and magnetic resonance imaging was performed for a single case. Typical computed tomography and magnetic resonance imaging findings, including morphology, texture and enhancement features, as well as clinicopathological characteristics and prognosis data were retrospectively analyzed.

Of eighteen PNET patients, fifteen were male and three were female, with a median age of 36 years (range, 2–65 years). The onset of symptoms was most often nonspecific and insidious. The mean tumor diameter was 7.2 cm (range, 3.0–12.1 cm), with necrosis in fifteen cases, cystic changes in eight, partition structure in five, calcification in five, hemorrhage in two, and mural nodules in one. Contrast enhanced computed tomography showed multiple tiny feeding arteries within the masses in six cases, resulting in a crab-like appearance, and mild ring enhancement pattern in five cases. Eleven cases showed surrounding invasion and metastasis. Of the eighteen PNET cases, nine cases showed smooth, well-defined margins, and nine cases had irregular, ill-defined margins. A median survival was 10.0±1.6 months. However, chemotherapy had efficacy on patients even those with advanced disease.

Primary intra-abdominal and retroperitoneal PNETs are rare, and imaging features documented here may help the diagnosis of this severe disease. Notably, two signs present in retroperitoneal PNET tumors, including a mild ring enhancement pattern and a crab-like appearance of the tiny feeding arteries, may have the potential to help us improve the ability to make a relatively reliable diagnosis.

A peripheral primitive neuroectodermal tumor (pPNET) is a small round cell tumor occurring mostly in children or young adults and categorized into the Ewing sarcoma family of tumors. pPNETs originating from the pancreas are especially rare, and only 25 cases have been reported in the literature. We report a case of a 22-year-old man who had a giant expansive tumor located in the uncinate process of the pancreas, 80 mm in diameter resulting in obstruction in the duodenum. The patient underwent a pancreaticoduodenectomy. The histological examination showed that the pancreatic tumor was composed of atypical small round cells. Immunohistochemical findings were positive for CD99. An Ewing sarcoma breakpoint region 1 gene 22q12 rearrangement was proven by a two-color fluorescence in situ hybridization assay. We diagnosed the tumor as a pPNET of the pancreas, which, according to the literature, is highly aggressive with poor prognosis. A multidisciplinary approach to treat these neoplasms should improve the prognoses.

• Ewing’s sarcoma
• FISH
• Pancreas
• Peripheral primitive neuroectodermal tumor
• Small round cell tumor
• Young adult