Primary Primitive Neuroectodermal Tumor Research Articles

Uncommon suspect: A case report of a rare renal neoplasm

Primitive neuroectodermal tumors (PNETs) are a group of rare and aggressive malignancies primarily found in children and young patients. Primary renal PNETs are very much uncommon and share clinical and radiological features with renal cell carcinoma (RCC), thus posing a significant diagnostic and therapeutic challenge. This case report presents the clinical, radiological, and pathological findings of a primary renal PNET in an adult female patient, mimicking the radiological appearance of RCC.

Primitive neuroectodermal tumors of the ovary: a multidecade review of the scientific literature.

Primitive neuroectodermal tumor (PNET) is a general term used in scientific literature for a heterogeneous group of small round-cell malignant tumors primarily arising from neural crest cells. These are extremely aggressive neoplasms which usually occur within soft tissue or bone of young adults. Ovarian tumors composed of primitive neuroectodermal elements are extremely rare, with only few case reports in scientific literature. Due to being so exceedingly rare, PNETs are frequently misdiagnosed and there are no standard therapeutic guidelines. Young patients seem to have better prognoses and individualized strategy is recommended. Limited data suggests that various gene deletions as well as amplifications may be crucial factors for tumorigenesis and the aggressive behavior of PNET. In this paper, we performed a brief review of all cases of primary ovarian PNETs published in the scientific literature to date, in regard to their clinical, histopathological, and therapeutic aspects, with the aim to provide a more comprehensive understanding of this exceedingly rare pathology.

Successful Management of Locally Advanced Primitive Neuroectodermal Tumor (PNET) of the Urinary Bladder: a Case Report and Literature Review

Background: Primitive neuroectodermal tumors (PNETs) are highly malignant neoplasms arise from neuroectodermal cells that have cholinergic features. These tumours are closely related to osseous or extraosseous Ewing’s sarcomas, with which they share the same chromosomal abnormality. Over the last few years, PNETs have been increasingly reported to occur in various organs, which may be due to recent progress in immunohistochemical techniques. PNETs arising in the urinary bladder are extremely rare, but more frequent in older adults. Case presentation: A 16 years Moroccan men old, who consults for a total hematuria and dysuria evolving for 2 months in a context of deterioration of the general state. Cyst biopsy was performed. The morphological result in favor of an undifferentiated round cell tumor process infiltrating the bladder muscle, the immu-histochemical study was in favor of a round cell tumor of the Ewing sarcoma/PNET type. Pelvic Magnetic resonance imaging MRI revealed the presence of an endovesical process invading the left antero-inferior pre-vesical fat. We decided, after a multidisciplinary consultation meeting, to start with two cycles of neoadjuvant chemotherapy, then to propose locoregional treatment, either radiotherapy or partial resection. The patient was put on the VAC/IE protocol with a clear regression in tumor size after two cycles. Conclusion: Both clinician and pathologist must be aware of this rare entity during diagnosis and management. Surgery or radiotherapy supported with chemotherapy should be considered an option, especially in advanced disease. Studies of more cases of primary PNET of the urinary bladder with longer follow-up periods are needed to clarify the clinical features and treatment.

Primary spinal peripheral primitive neuroectodermal tumour: a report of 3 cases and review of the literature

Peripheral primitive neuroectodermal tumours (PNETs) are rare and highly malignant tumours in the spine, with a predilection for young adults. There are no standard guidelines for treating these tumours. Surgical resection combined with postoperative radiotherapy and chemotherapy is a common and effective treatment at present. Even so, survival time of patients with these tumours is still very short. In this study, we present three rare cases of thoracic epidural PNETs and review the literature.

Primary primitive neuroectodermal tumour of the kidney in adults: Experience of managing 12 cases with systematic review and pooled analysis of literature.

Primitive neuroectodermal tumor (PNET) of the kidney is unusual in adults. These tumours are diagnosed mainly on histopathology and that too sometimes has limitations. With this study, we aimed to review our clinical and histopathological data of patients with renal PNET and reviewing the world literature. In this retrospective study, we reviewed our database from January 2006 to July 2018 to include all the cases of primary PNET of the kidney. We also performed systematic literature search to identify all the relevant series on renal PNET. A total of 12 patients including 5 men and 7 women were managed during the above mentioned period. Out of these 7 patients, 2 patients had metastasis at diagnosis, one had locally advanced disease, 6 underwent radical nephrectomy, 5 patients received adjuvant chemotherapy (two currently receiving) and only 1 patient received adjuvant radiotherapy (RT). On Immunohistochemistry (IHC), CD99 and FLI1 were positive in all the patients. Median survival was 10months. In our review 10 studies were included, 38.6% of the patients had metastatic disease and 10.7% had locally advanced disease at diagnosis. Overall mean survival was 33.75months. CD99 and FLI1 were positive in 94.3% and 78.5%, respectively. PNET remains a pathological diagnosis and IHC has important place in diagnosis of PNET. Locally advanced and metastatic disease is common at diagnosis leading to overall poor survival.

Primary primitive neuroectodermal tumor of the adrenal gland: A unique tumor at an unusual site

Ewing sarcoma/Primitive Neuroectodermal Tumor (ES/PNET) is a malignant small round blue cell tumor of neuroectodermal origin that affects bones and soft tissue in children and young adults. ES/PNET is very uncommon in parenchymal organs. We report a case of primary adrenal PNET in a young female having pregnancy induced persistent hypertension. She underwent right adrenalectomy for a large adrenal mass. On histopathology, it was typical malignant round cell tumor (MRCT). Immunohistochemistry confirmed the diagnosis of ES/PNET with expression of CD99, FLI-1 and NKX2.2. Until now, only 38 cases of primary adrenal ES/PNET have been reported in the English literature with just 5 cases from India. Adrenal ES/PNET can be mistaken with other MRCTs like Non-Hodgkin lymphoma and neuroblastoma. Since the biology, treatment and prognosis of these tumors is entirely different, we emphasize that pathologists must be aware of this possibility and try to differentiate them using ancillary techniques.

Analysis of Clinical, Imaging, and Pathologic Features of 36 Patients with Primary Intraspinal Primitive Neuroectodermal Tumors: A Case Series and Literature Review.

Primary intraspinal primitive neuroectodermal tumors (PNETs) account for ∼0.4% of all intraspinal tumors, but information about these tumors in the medical literature is limited to single case reports. We report four cases of primary intraspinal PNETs and present a systematic literature review of the reported cases. We retrospectively reviewed and analyzed the clinical data of 4 patients with primary intraspinal PNETs who underwent neurosurgical treatment at our clinic between January 2013 and January 2020, and of 32 cases reported in the literature. The female-to-male ratio was 2.6:1. The mean patient age was 21.42 ± 15.76 years (range: 1-60 years), and patients <36 years of age accounted for 83.30% of the study cohort. Progressive limb weakness and numbness were the chief symptoms (accounting for ∼55.6%). The mean complaint duration was 0.89 ± 0.66 months for males and 2.72 ± 3.82 months for females (p = 0.028). Epidural (41.7%) was the most common site, and thoracic (47.3%) was the most frequent location. Most PNETs were peripheral, and magnetic resonance imaging (MRI) appearance was isointense or mildly hypointense on T1-weighted images and hyperintense on T2-weighted images. Homogeneous contrast enhancement was observed. The 1-year survival rate of patients who underwent chemoradiation after total or subtotal lesion resection was better compared with patients who did not undergo chemotherapy, radiotherapy, or total or subtotal resection. The modality of treatment was associated with survival time (p = 0.007). Primary intraspinal PNETs mainly occur in young people with a female preponderance. In patients with a rapid loss of lower limb muscle strength and large intraspinal lesions on MRI, PNETs should be considered. Surgical resection and adjuvant radio chemotherapy are key prognostic factors.

An interesting case of 3‘P’s – Primary Pericardial Primitive neuroectodermal tumor in an infant: A case report

Cardiac malignancies presenting in the infancy are rare. Primitive neuroectodermal tumor (PNET), a high-grade malignant tumor is one among them. The most common sites of occurrence of primary PNET are the peripheral nervous system, bone, and deep soft tissues. It is extremely rare in the pericardium. To the best of our knowledge, only three patients with primary PNET of the pericardium have been reported so far in the literature. We report a case of primary PNET of the pericardium in a 11-months-old female child, who was referred to our hospital with complaints of dyspnea and difficulty in feeding of 5 days duration. At presentation, she had massive pericardial effusion with tamponade and an echogenic intrapericardial mass. An emergency pericardiocentesis was done to relieve the tamponade. After stabilization, the Computer tomography (CT) imaging of the chest revealed a soft tissue mass with non-enhancing cystic areas in the pericardium with features suggestive of PNET. After two days, the child had a cardiac arrest and succumbed to death.

Spinal Primitive Neuroectodermal Tumor (PNET) in a 64-year-old Male Treated with Surgery, Radiotherapy, and Chemotherapy: A Case Report

Primitive neuroectodermal tumors (PNETs) are a heterogeneous group of malignant neoplasms found primarily in childhood and early adulthood. In this paper, we described the case of a 64-year-old male with primary spinal PNET, successfully treated with surgery, craniospinal radiotherapy, and concurrent chemotherapy. This is the case of a 64-year-old male who presented with a 2-month history of bilateral lower extremity weakness and numbness associated with urinary and bowel incontinence. Work-up was done, and the spine's plain magnetic resonance imaging (MRI) revealed a heterogeneously enhancing intradural lesion with an extradural component at the right T9/T10 level, causing mild to moderate cord compression. The patient underwent laminectomy and gross total resection of the said tumor. Histology and immunohistochemistry were consistent with a primitive neuroectodermal tumor of the spine. The tumor recurred three months after the surgery, and the patient was then referred for radiation therapy with concurrent chemotherapy. Repeat spinal MRIs with three- to six-month intervals after treatment showed no tumor recurrence as of August 2021. Primary spinal PNETs are rarely found in adults, especially in the elderly. These tumors currently have no recommendations or guidelines regarding their management. Thus, most cases are presently being managed based on studies on children and central nervous system (CNS) PNETs. This paper presented a case of a successfully treated primary spinal PNET in the elderly. The management was primarily based on studies done on that of the pediatric population and CNS PNETs.

Primary primitive neuroectodermal tumor of the kidney: A rare case report and review of literature

Primitive neuroectodermal tumors (PNET) is an aggressive, rapidly progressing and metastatic tumor. It rarely arises from the kidney and has an incidence of less than 1%. These are usually mistaken for a wide variety of other small round cell tumors. Young adults and children are commonly affected and have an aggressive course. These tumors are mistaken for a wide variety of other small round cell tumors. Here is a case of a 52-year-old female, who presented with flank pain and gross hematuria. The contrast-enhanced computerized tomogram (CECT) revealed a renal mass with a tumor thrombus extending to the renal vein, inferior vena cava, and the right side of the heart. The patient underwent radical nephrectomy along with IVC thrombectomy and chemotherapy. The sections from formalin-fixed surgical specimens were paraffin-embedded and stained with H &amp; E stain. Immunohistochemistry (IHC) was performed.Histology revealed small round to oval cells with hyperchromatic nucleus and very scanty cytoplasm. Frequent mitotic figures were noted. Few rosettes were seen at places. Tumor was seen invading the perirenal adipose tissue. The tumor thrombus extended into the right atrium and the right ventricle. IHC evaluation revealed the tumor cells showed a strong positivity for CD99, synaptophysin, neuron-specific enolase, vimentin, and were negative for CD45, pan-cytokeratin, and desmin. Thus, the histological examination and IHC helped in getting a definite diagnosis of PNET involving the kidney. The patient has been undergoing chemotherapy. PNET has an aggressive clinical course with a poor prognosis. Renal PNET bears many similarities to other small round cell tumors; hence it is important to review the histologic features and immunostaining for definitive diagnosis. Due to the rarity of the disease, there is no standard guideline regarding its management. Achieving accurate diagnosis facilitates the prolongation of survival with definitive treatment.

Primary Pulmonary Primitive Neuroectodermal Tumor: A Case Report and Literature Review

Primitive Neuroectodermal Tumors (PNET) and Ewing Sarcoma (EWS) belong to the same family of malignant, small, round cell neoplasms of soft tissue or bone origin. Common locations for EWS-PNET include chest wall, pelvis, and extremities. EWSPNETs that arise in the lung parenchyma without chest wall involvement are extremely rare in adults. We report a case of EWS-PNET of the lung in an adult and review the distinct clinical, pathological, and molecular features of these tumors.

Primary primitive neuroectodermal tumor of the orbit in an adult: Case report and literature review

Background: Primitive neuroectodermal tumors (PNETs) are malignant soft tissue tumors of neuroepithelial origin with an aggressive nature and associated with early disseminated metastasis, resulting in poor prognosis. It occurs more frequently in men of age &lt; 35 years, and in several parts of the body, such as pulmonary tract, nasal cavity, paranasal sinuses, and/or neck. Orbital location is infrequent and has been reported in less than 20 cases in the English literature so far.&#x0D; Case presentation: In this paper, we report our experience with a 77 year-old man who was referred with a 2.8 cm mass in the superior-anterior quadrant of his left eye for 2 weeks prior to admission, as well as having a 15-kg weight loss during the past six months. The patient developed rapidly progressive visual loss, decreased eye movements, and conjunctivitis within a week. Thus, the patient underwent orbitotomy and the results of histological examination and immunohistochemistry showed an orbital PNET. Metastasis to frontal sinuses and ethmoid sinuses were also discovered. The patient passed away before referral to the oncologist.&#x0D; Conclusion: This report confirms the highly aggressive nature of PNET and reports its rare occurrence in orbital cavity.

Primary Primitive Neuroectodermal Tumor of the Parotid: An Unsuspected Diagnosis

Primitive neuroectodermal tumors (PNETs) are extremely rare tumors. These neoplasms can occur at sites outside of the central nervous system. The head and neck location is unsual. We report a case with primitive neuroectodermal tumor (PNET) of the parotid. We analyze through this observation the clinical, histological and therapeutic characteristics of this entity.

Primary primitive neuroectodermal tumor of the breast: Analysis of clinical outcomes of twenty-one patients.

Primary primitive neuroectodermal tumor of the breast: Analysis of clinical outcomes of twenty-one patients.

Primary pelvic primitive neuroectodermal tumor: A rare tumor in an adult male

Primitive neuroectodermal tumor is a rare tumor involving the genitourinary system. Primary pelvic primitive neuroectodermal tumors are extremely rare in an adult male. We report a case of a young adult with large primary pelvic primitive neuroectodermal tumor.

Metastatic Primitive Neuroectodermal Tumor Arising from Stomach: A Case Report

Gastric primitive neuroectodermal tumor (PNET) is extremely rare and treatment of metastatic gastric PNET is not established. Herein, we report a case of a 54-year-old male who had undergone total gastrectomy with D2 lymph node dissection, distal pancreatectomy, and splenectomy for the curative intent of primary gastric PNET initially and received multimodal treatment including chemotherapy, radiotherapy, and palliative metastasectomy after recurrence and metastasis. He died 5.6 years after first diagnosis and 4.2 years after relapse due to disease progression. Although no effective chemotherapy agents and standard treatments have been determined, multimodality treatment approach applied to this patient has helped to achieve relatively long-term survival. This case report will be helpful to identify the disease progress and prognosis of gastric PNET and to know the effects of various treatment methods.

Second New Primary PNET of Kidney in a Treated Case of Carcinoma Breast: A Case Report

Primitive Neuroectodermal Tumour (PNET) is a member of small round cell “Blue tumour” family. The overall incidence of PNET is &lt;1%. PNET of kidney is uncommon and was first reported in 1975. Since the first report around 150 cases have been published in medical literature. It exhibits highly aggressive behaviour. It usually affects young adults and has a male predominance of 3:1. Only six cases of PNET of kidney have been reported in older patients and PNET of kidney as a second new primary has rarely been reported, only three cases of renal PNET with history of an earlier or synchronous primary cancer were reported in literature from the USA, Germany and China. Here, the author reported a case of renal PNET in a 48-year-old female who has been treated for right breast cancer by surgery, adjuvant chemotherapy and radiotherapy three years (July 2015) prior to diagnosis of PNET of left kidney. Upon diagnosis, patient underwent left nephrectomy. Postoperatively, patient was started on Ewing’s Family of Tumours (EFT) 2001 protocol. Patient completed induction therapy followed by radiation to tumour bed with concurrent weekly single agent vincristine and was planned for maintenance chemotherapy. After one cycle of maintenance chemotherapy, patient developed severe febrile pancytopenia and was admitted in the ICU, even after aggressive medical line of management, patient could not be revived. Although, the patient tolerated the treatment protocol for breast malignancy well and the primary was under control but after three years, with the diagnosis of a very rare second new primary PNET of left kidney which has a very aggressive nature and poor prognosis, the patient could not tolerate the multimodality treatment which was required.

Primary Primitive Neuroectodermal Tumor of Isthmus Associated with Endometrioid Adenocarcinoma of Uterus Presenting as Cervical Polyp

Primitive neuroectodermal tumor (PNET) of isthmus is a rare entity. Difficulties are encountered in diagnosis, and there is no standard therapy for uterine or cervical PNETs. A 43-year-old nulliparous woman was diagnosed to have abnormal uterine bleeding with severe anemia, and on examination, there was a large necrotic polyp occupying the two-third of vagina. The initial biopsy from the polyp was a necrotic tissue, and the polypectomy specimen after correction of anemia reported as PNET. Staging laparotomy and TAH with BSO were undertaken, and the specimen revealed the origin of polyp from the isthmical part of uterus, and the histopathological examination was reported as endometrial adenocarcinoma grade I with less than 50% of the myometrial invasion, and the parametria, vaginal cuff and cervix were free of tumor. She did not receive any adjuvant therapy and on follow-up of 5 years did not develop any recurrence. PNET of uterus can present as a polyp, and the association of endometrial carcinoma is difficult to diagnose in such cases. Though adjuvant chemotherapy is desirable for PNET to prevent recurrence, stage I disease may achieve cure with surgery alone.

An unusual natural history of a rare bladder tumor: Primitive neuroectodermal tumor.

A primary primitive neuroectodermal tumor (PNET) of the urinary bladder is a very rare bladder tumor. There are few described cases in the literature to date. We presented a 70-year-old man with primary nonmetastatic bladder PNET. The diagnosis was confirmed according to immunohistochemistry evaluation. The patient underwent bladder-sparing protocol using radiotherapy and standard systemic multidrug chemotherapy (vincristine + doxorubicin + cyclophosphamide). At the end of three years of follow-up, we performed radical cystoprostatectomy due to newly diagnosed high-grade transitional cell carcinoma of the bladder at the site far from the primary bladder PNET. In conclusion, multimodal bladder sparing protocol including radiotherapy and standard systemic chemotherapy can be used for the management of primary bladder PNET with acceptable oncological outcomes.

Ovarian primary primitive neuroectodermal tumor: a review of cases at PUMCH and in the published literature

BackgroundThe pathological characteristics, treatment strategies and prognosis of ovarian primary primitive neuroectodermal tumor (PNET) were unclear due to the rarity of PNET. All cases treated at Peking Union Medical College Hospital (PUMCH) between 1975 and 2016 and published in the English literature between 1980 to 2017 were reviewed.ResultsFinally four cases from PUMCH and 15 cases in the literature were included. The median age was 25 years (range 13–79), and the median diameter of the tumors was 13.4 cm (range 5.0–30.0). The most common initial symptoms were abdominal pain, bloating and a pelvic mass. Diagnosis primarily depended on immunohistochemical and fluorescence in situ hybridization data. Treatment consisted of surgery, various chemotherapy regimens and/or radiotherapy. The 5-year overall survival (OS) and progression-free survival (PFS) rates were 15 and 52%, respectively. For patients with OS and PFS > 12 months, the median ages were 21 years (range 13–35) and 17 years (range 13–35), respectively, while for patients with OS < 12 months and PFS < 12 months, the median ages were 48 years (range 14–79) and 25 years (range 18–79), respectively.ConclusionsNo standard therapy for ovarian primary PNET exists, and an individualized strategy is recommended. Young patients seem to have better prognoses.