Diffuse Pediatric-type High-grade Glioma Arising in an Ovarian Mature Cystic Teratoma

Immature neuroectodermal tissue can be found in the ovary as part of an immature teratoma or as part of a teratoma with malignant neuroectodermal transformation. Such lesions may closely resemble central nervous system tumors, but their biologic similarity is unclear. We describe an 18-yr-old female who presented with abdominal pain caused by an ovarian mass with widespread metastases. Histology showed a primitive, high-grade tumor arising in the background of a mature teratoma. The tumor was SOX10 positive, with focal expression of GFAP, S100, NSE, and synaptophysin. Molecular analysis demonstrated co-amplification of PDGFRA and KIT , alterations common in high-grade gliomas. By whole-genome methylation profiling, it clustered into the "diffuse pediatric-type high-grade glioma, RTK1 subtype, subclass c" group. Despite progressing through 2 lines of chemotherapy with widespread metastatic disease, she achieved an excellent response to chemotherapy directed toward aggressive germ cell tumors. This case emphasizes the importance of immunohistochemical, genomic, and epigenetic analyses to accurately classify these exceedingly rare tumors and determine the optimal therapy.

Conventional and advanced MR imaging findings of primary Ewing sarcoma of the tentorium: a case report with literature review

BACKGROUND

Primary intracranial Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET) is an extremely uncommon tumor. Care should be taken as it can be mistaken for a meningioma radiologically.

CASE DESCRIPTION

This paper reports a case of a 44-year-old male presenting with headache. A magnetic resonance imaging demonstrated a mass involving the tentorium, cerebrum and cerebellum with solid-cystic component. The solid component was hyperintense on T1-weighted images with significant enhancement. There was restriction in diffusion-weighted images and microhemorrhagic signal change in susceptibility weighted images. MR perfusion revealed increased relative cerebral blood volume and mean transit time values. Surgical pathology was reported as ES.

CONCLUSIONS

Intracranial ES/pPNET is a rare tumor that generally arises from the meninges. It must be distinguished from meningioma since it can be mistaken radiologically, because the treatment and prognosis are quite different. Localization and conventional MR signal characteristics of both lesions are similar. Whereas, MR perfusion findings may be helpful in discrimination.

Primitive neuroectodermal tumor of the pancreas

Primitive neuroectodermal tumors (PNETs) are rare small round cell malignancies closely related to Ewing's sarcoma. Involvement of the abdominal cavity, specifically the pancreas, is extremely rare. PNETs affect predominantly children and young adults. The clinical presentation is mostly vague, with a short history of symptoms even in metastatic disease. Findings on imaging studies are nonspecific. The diagnosis can be suggested by the microscopic appearance of the tumor cells, but should be confirmed by histology, immunohistochemistry, fluorescence in situ hybridization, immunoreactivity evaluation of MIC2-protein (CD99) expression, and when possible testing for the chromosome translocation t(11;22) (q24,q12). In adults, the prognosis is poor with no standard treatment. Here, we present a case of pancreatic PNET in a 61-year-old man who presented with persistent abdominal pain and weight loss.

Primary adult primitive neuroectodermal tumor of the bladder: A case report and literature review

RATIONALE

A primary primitive neuroectodermal tumor (PNET) is a rare and highly malignant tumor that often occurs in the central nervous system of children and young adults. This tumor is rarely observed in the bladder.

PATIENT CONCERNS

In this paper, we describe the case of a 64-year-old man with a PNET of the bladder. He experienced dull pain in the lower left abdomen for 5 months (without any obvious inducement), which gradually became aggravated and intolerable.

DIAGNOSES

Partial cystectomy was performed, and a PNET of the bladder, which is extremely rare, was confirmed.

INTERVENTIONS

Following cystectomy, the patient's general postoperative state was poor and he could not tolerate chemotherapy. Thus, he was subjected to pelvic radiotherapy for 2 weeks.

OUTCOMES

His physical condition did not improve significantly after radiotherapy; however, we still plan to continue it. If the patient's physical condition improves, chemotherapy will be considered.

LESSONS

Most cases of PNETs are intravesical or at least mainly endophytic. However, in this case, the mucosal layer was barely involved, and the tumor mainly grew out of the bladder, which is very rare. The present case provides reference for the diagnosis of PNET.

Melanotic Neuroectodermal Tumor of Infancy: A Rare Case Report

A rare case melanotic neuroectodermal tumor of infancy occurring in 2-year-old girl affecting left maxilla is described. Computed tomography showed benign expansile type of lesion affecting left maxilla. The lesion was surgically excised completely. Histopathology confirmed the diagnosis of melanotic neuroectodermal tumor. Four months' follow-up showed no recurrence.

Epididymal melanotic neuroectodermal tumor of infancy: A rare cause of scrotal mass in an infant

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, benign neoplasm of neural crest origin more commonly seen in the craniofacial region. We report a case of MNTI of the epididymis in a 6-month-old male child with emphasis on the sonographic appearance which has not been previously described. In this case, the mass was inseparable from the testicle and therefore the differential diagnosis considered both extratesticular and intratesticular masses. MNTI should be added to the differential diagnosis of scrotal masses, particularly if they present in a child younger than 12 months of age.

Cervicomedullary primitive neuroectodermal tumor of the spine: Case report

Background

Intramedullary primitive neuroectodermal tumors (PNETs) are tumors found rarely in the cervical region, with only five such cases described in the literature. The available literature contains only one report regarding cervicomedullary junction PNET.

Case Description

The authors present a case report of a 45-year-old male patient who had undergone urgent hospitalization owing to progressive tetraparesis and subtle impairment of respiratory function. He underwent magnetic resonance imaging, which showed an extensive enhancing cervical intramedullary tumor extending from C5 to the bulbar region. Since he developed severe impairment of respiratory function, he required tracheostomy. He then underwent microsurgery 2 days after his admission, and a partial tumor resection was performed. The pathological diagnosis of PNET of the cervicomedullary junction (CMJ) was made. He had slight worsening of strength after surgery with subsequent deterioration over the next 3 weeks. The tumor displayed aggressive growth; thus, radiotherapy was indicated. Unfortunately, he developed severe febrile neutropenia and died after 2 weeks of radiotherapy. Given the rarity of the condition, we wish to review the epidemiology, pathophysiology, and treatment options of his population.

Conclusion

Intramedullary PNETs of the cervical spine and CMJ are exceedingly rare in adults; treatment of such patients remains a challenge, despite the modern neurosurgical armamentarium that is available.

Expression of neural cell adhesion molecule L1 (CD171) in neuroectodermal and other tumors: An immunohistochemical study of 5155 tumors and critical evaluation of CD171 prognostic value in gastrointestinal stromal tumors

The neural cell adhesion molecule L1 (CD171) is a multidomain type 1 membrane glycoprotein of the immunoglobulin superfamily important in the nervous system development, kidney morphogenesis, and maintenance of the immune system. Recent studies reported CD171 expression being associated with adverse clinical outcome in different types of cancer and there has been a growing interest in targeting this cell membrane molecule on neoplastic cells by chimeric antigen receptor redirected T lymphocytes or specific antibodies. Nevertheless, conflicting results regarding the prognostic value of CD171 expression in renal cell carcinomas and gastrointestinal stromal tumors were published. In this study, CD171 expression was immunohistochemically analyzed in 5155 epithelial, mesenchymal, melanocytic, and lymphohematopoietic tumors to assess its utility in diagnostic pathology and to pinpoint potential targets for CD171-targeting therapy. A newly developed anti-CD171 rabbit monoclonal antibody, clone 014, was selected from the panel of commercially available CD171 antibodies. Immunohistochemistry was performed using Leica Bond Max automation and multitumor blocks containing up to 60 tumor samples. CD171 was constitutively and strongly expressed in neuroectodermal tumors such as schwannoma, neuroblastoma, and paraganglioma, whereas other mesenchymal tumors including schwannoma mimics showed only rarely CD171 positivity. Frequent CD171-expression was also detected in ovarian serous carcinoma, malignant mesothelioma, and testicular embryonal carcinoma. CD171 immunohistochemistry may have some role in immunophenotypic differential diagnosis of neurogenic tumors and pinpointing potential candidates for anti-CD171 therapy. Though, because of its rare expression and lack of predictive value, CD171 is neither a diagnostic nor prognostic marker for gastrointestinal stromal tumors.

Extraosseous Ewing's Sarcoma of the Pancreas: An Uncommon but Treatable Disease

Extraosseous Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is a rare but aggressive and malignant tumor, and has been reported in various sites such as the lungs, biliary tract, kidney, prostate, stomach, esophagus, oral cavity, salivary glands, urinary bladder, uterus, cervix, gonads, and vagina. However, the pancreas is considered to be an extremely uncommon site and only a handful of cases have been published to date. We present here another case of a pancreatic ES/PNET. Our case intensifies the importance to recognize this rare type of tumor in the pancreas as there is a broad spectrum of tumors with a similar morphology that includes sheets of small, round blue cells. As observed in our present case, this problem is markedly challenged when the tumor site of origin is uncertain.

Primitive Neuroectodermal Tumor of Nasal Cavity on 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography

Primitive neuroectodermal tumor is a malignant small round cell tumor of presumed neural crest origin, usually affecting the bony structures of the nasal cavity and its clinical and radiological features may be confused with those of infection and malignancy. I report a case with primitive neuroectodermal tumor of the nasal cavity showing increased tracer uptake on ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography mimicking an another primary malignancy in a 17-year-old boy.

Late onset of primary pulmonary primitive neuroectodermal tumor: a case report

Lungs are one of most metastatic areas for primitive neuroectodermal tumor (PNET), however primary pulmonary PNET is extremely rare. Here we present a case of a 58-year-old male patient with a tumor in the right lung that originated from the lung but not from chest wall. Patient was diagnosed with PNET following histological and immunohistochemical examination of CT-guided percutaneous tru-cut needle biopsy and no distant metastasis were detected in PET-CT scan. As advised recently in published literature, surgical resection following neoadjuvant chemotherapy protocol is preferred in the treatment of our patient as it has better success of complete resection leading to higher 5-year survival rates. Although primary pulmonary PNET is uncommon, it should be taken into account and complete surgical resection should be aimed as treatment to achieve higher survival rates.

Melanotic schwannoma of the L5 root

Melanotic neoplasm of the central nervous system is rare and the majority of them are metastatic. Melanotic schwannoma (MS) is an unusual variant of nerve sheath neoplasm accounting for less than 1% of primary nerve sheath tumors. A case involving a 36-year-old man with MS at the L5 root is presented. Surgery, differential diagnosis, radiology, histology, and treatment of this rare entity are discussed.

Ectopic sphenoid sinus pituitary adenoma (ESSPA) with normal anterior pituitary gland: a clinicopathologic and immunophenotypic study of 32 cases with a comprehensive review of the english literature

Ectopic sphenoid sinus pituitary adenoma (ESSPA) may arise from a remnant of Rathke's pouch. These tumors are frequently misdiagnosed as other neuroendocrine or epithelial neoplasms which may develop in this site (olfactory neuroblastoma, neuroendocrine carcinoma, sinonasal undifferentiated carcinoma, paraganglioma, melanoma). Thirty-two patients with ESSPA identified in patients with normal pituitary glands (intact sella turcica) were retrospectively retrieved from the consultation files of the authors' institutions. Clinical records were reviewed with follow-up obtained. An immunohistochemical panel was performed on available material. Sixteen males and 16 females, aged 2-84 years (mean, 57.1 years), presented with chronic sinusitis, headache, obstructive symptoms, and visual field defects, although several were asymptomatic (n = 6). By definition, the tumors were centered within the sphenoid sinus and demonstrated, by imaging studies or intraoperative examination, a normal sella turcica without a concurrent pituitary adenoma. A subset of tumors showed extension into the nasal cavity (n = 5) or nasopharynx (n = 9). Mean tumor size was 3.4 cm. The majority of tumors were beneath an intact respiratory epithelium (n = 22), arranged in many different patterns (solid, packets, organoid, pseudorosette-rosette, pseudopapillary, single file, glandular, trabecular, insular). Bone involvement was frequently seen (n = 21). Secretions were present (n = 16). Necrosis was noted in 8 tumors. The tumors showed a variable cellularity, with polygonal, plasmacytoid, granular, and oncocytic tumor cells. Severe pleomorphism was uncommon (n = 5). A delicate, salt-and-pepper chromatin distribution was seen. In addition, there were intranuclear cytoplasmic inclusions (n = 25) and multinucleated tumor cells (n = 18). Mitotic figures were infrequent, with a mean of 1 per 10 HPFs and a <1% proliferation index (Ki-67). There was a vascularized to sclerotic or calcified stroma. Immunohistochemistry highlighted the endocrine nature of the tumors, with synaptophysin (97%), CD56 (91%), NSE (76%) and chromogranin (71%); while pan-cytokeratin was positive in 79%, frequently with a dot-like Golgi accentuation (50%). Reactivity with pituitary hormones included 48% reactive for 2 or more hormones (plurihormonal), and 33% reactive for a single hormone, with prolactin seen most frequently (59%); 19% of cases were non-reactive. The principle differential diagnosis includes olfactory neuroblastoma, neuroendocrine carcinoma, melanoma, and meningioma. All patients were treated with surgery. No patients died from disease, although one patient died with persistent disease (0.8 months). Surgery is curative in the majority of cases, although recurrence/persistence was seen in 4 patients (13.8%). In conclusion, ESSPAs are rare, affecting middle aged patients with non-specific symptoms, showing characteristic light microscopy and immunohistochemical features of their intrasellar counterparts. When encountering a tumor within the sphenoid sinus, ectopic pituitary adenoma must be considered, and pertinent imaging, clinical, and immunohistochemical evaluation undertaken to exclude tumors within the differential diagnosis. This will result in accurate classification, helping to prevent the potentially untoward side effects or complications of incorrect therapy.

Primary primitive neuroectodermal tumor: An unusual cause of right ventricular intracavitary obstruction in a child

A six-year-old boy presented with a brief history suggestive of right heart failure. Investigations revealed a mass filling almost the entire right ventricle. Palliative resection of the mass was done. The operative specimen revealed a primary primitive neuroectodermal tumor of the heart, the first of its kind reported in the pediatric age group.