Unusual Imaging Findings Associated with Germ Cell Tumors.

Germ cell tumors, because they contain immature and mature elements, can differentiate into different tissue types. They can exhibit unusual imaging features or manifest in a syndromic fashion. The authors describe these features and assign them to one of the following categories: (a) unusual manifestations of metastatic disease (growing teratoma syndrome, choriocarcinoma syndrome, ossified metastases, and gliomatosis peritonei); (b) autoimmune manifestations (sarcoidlike reaction and paraneoplastic syndromes); (c) endocrine syndromes (sex hormone production, struma ovarii, and struma carcinoid); or (d) miscellaneous conditions (ruptured dermoid cyst, squamous cell carcinoma arising from a mature teratoma, Currarino triad, fetus in fetu, pseudo-Meigs syndrome, and pancreatitis). Rare conditions associated with germ cell tumors demonstrate characteristic imaging findings that can help lead to the appropriate diagnosis and management recommendations. When evaluating for potential metastatic disease, alternative benign diagnoses should be considered (eg, growing teratoma syndrome, ossified metastases, ruptured dermoid cyst, gliomatosis peritonei, and sarcoidlike reaction), which may impact management. Germ cell tumors may also lead to life-threatening complications such as extensive hemorrhage from choriocarcinoma metastases or the rupture of mature teratomas, cases in which timely diagnosis is crucial. Autoimmune and endocrine manifestations such as paraneoplastic encephalitis, autoimmune hemolytic anemia, and hyperthyroidism may occur owing to the presence of germ cell tumors and can create a diagnostic dilemma for clinicians. Knowledge of the syndromic and unusual imaging findings associated with germ cell tumors helps guide appropriate management. ©RSNA, 2019.

Activation of the basal cell carcinoma pathway in a patient with CNS HGNET-BCOR diagnosis: consequences for personalized targeted therapy.

High grade neuroepithelial tumor of the central nervous system with BCOR alteration (CNS HGNET-BCOR) is a recently described new tumor entity with a dismal prognosis. The objective of this study was to identify and validate pathways deregulated in CNS HGNET-BCOR as basis for targeted therapy approaches.We characterized the BCOR alteration in a pediatric patient with CNS HGNET-BCOR diagnosis by Sanger sequencing and demonstrated an elevated BCOR expression by qRT-PCR and western blot. By whole transcriptome sequencing and Ingenuity Pathway Analysis, we identified the activation of the Sonic Hedgehog (SHH) and of the WNT signaling pathway in two different regions of the primary tumor and of one inoculation metastasis compared to normal brain. We validated the activation of the SHH and of the WNT pathway by qRT-PCR analysis of GLI1 and AXIN2 respectively. GLI1 and AXIN2 were upregulated in the primary tumor and in two inoculation metastases compared to normal brain. Mutational analysis of SMO, PTCH1 and SUFU, three key components of the SHH pathway, revealed a Single Nucleotide Polymorphism (SNP) in PTCH1 (rs357564). We tested the effect of the GLI-inhibitor arsenic trioxide (ATO) on a short-term cell culture isolated from the metastasis. ATO was able to reduce the viability of the cells with an IC50 of 1.3 µM.In summary, these results provide functional evidence of altered BCOR expression and homogeneous coactivation of both the SHH and WNT signaling pathways, building the basis for potential novel therapeutic approaches for patients with a CNS HGNET-BCOR diagnosis.

Distant dissemination of mixed low-grade astroblastoma-arteriovenous malformation after initial operation: a case report.

We present a rare case of low-grade astroblastoma coexisting with an arteriovenous malformation (AVM) underwent surgery two times in a 38-year-old man. After the first surgery, this case was reported as a mixed low-grade astroblastoma and AVM. The lesion was completely resected surgically along with AVM. The patient underwent postoperative radiotherapy. Twenty months later, MRI showed enhanced lesions in suprasellar, pineal region and multiple small lesions in the spinal cord, whereas completely no recurrent lesion at the primary tumor site. So, the patient rationally underwent surgical removal in suprasellar and pineal region. After the second surgery, this case was diagnosed as a high-grade astroblastoma. Cells from the second surgical specimens showed high MIB-1 index and an increased olig-2 index. In addition, it is not common for low-grade astroblastoma metastasis to suprasellar, pineal region and spine with completely no recurrence at the original primary tumor site. Therefore it is difficult to predict tumor behavior and patient's clinical outcome merely based on histologic features. The important issue is whether the AVM was thought to be the cause of poor progress of this tumor. More cases are needed to confirm this. Classification and histogenesis of this tumor is still debated. Lack of clinicopathological correlation makes the prognosis of this tumor unpredictable. Anyway, we should be very discreet to treat the astroblastoma, even for low-grade astroblastoma.

Ovarian immature teratoma with gliomatosis peritonei and pleural glial implant: a case report.

Gliomatosis peritonei is a very rare phenomenon occurring almost exclusively in association with ovarian immature teratoma. It is characterized by numerous benign, mature glial nodules in the omentum and mesentery. The presence of glial tissue outside abdominal cavity is extremely rare in the setting of ovarian immature teratoma. We present a case of ovarian immature teratoma with both gliomatosis peritonei and pleural glial implant in a 4-year-old girl. Glial emboli were present in the pleural implant, suggesting lymphovascular dissemination might be the cause of extra-abdominal glial implantation.

Intraventricular dysembryoplastic neuroepithelial tumor-like neoplasm with disseminated spinal tumor.

Dysembryoplastic neuroepithelial tumor (DNT)- like lesions arise in extracortical locations and behave in a benign fashion similar to that of cortical DNTs. They usually come to attention by symptoms and signs of increased intracranial pressure rather than focal neurological impairment. Here we report a case of 9-year-old boy with a complaint of headache and back pain. A third ventricular mass lesion with disseminated spinal tumor was detected on his magnetic resonance imaging. The presence of floating neurons in a mucinous matrix, oligodendrocyte-like cells (OLCs) aligning axonal columns and vessels, immunohistochemical profile of the neoplasm in addition to the clinical and radiological manifestations of the patient led to the diagnosis of "DNT-like neoplasm of the third ventricle".

Ganglioneuroma of the mandible resulting from metastasis of neuroblastoma.

Neuroblastoma, ganglioneuroblastoma and ganglioneuroma are neuroblastic tumours derived from primordial neural crest tissue. The authors report a rare presentation of a ganglioneuroma of the mandible arising from a metastasis of an adrenal neuroblastoma. The pathogenesis and behaviour of ganglioneuromas is discussed, together with recommendations for their management.

Consecutive histological changes in an astroblastoma that disseminated to the spinal cord after repeated intracranial recurrences: a case report.

A 17-year-old male patient underwent surgery five times (four consecutive intracranial tumor removal surgeries and a final spinal tumor removal surgery). After the third surgery, this case was reported as a low-grade astroblastoma that is characterized by perivascular pseudorosettes consisting of elongated tumor cells arranged around the blood vessels. However, the fourth and fifth surgical specimens demonstrated very interesting histological changes in the astroblastoma. Through the course of relapses, the constituent cells of the astroblastic perivascular rosettes became smaller and rounder, and a multilayered cell arrangement was observed. The nucleus-to-cytoplasm ratio increased, and the compact intervascular cells ultimately lost glial fibrillary acidic protein (GFAP) expression. These undifferentiated cells showed high MIB-1 indices and an increased olig2 index. On the other hand, the cells in all the surgical specimens were positive for certain neuronal markers such as NSE, TUJ1, and nestin. Some astroblastomas may be more immature than the usual astrocytes; however, it is necessary to study more cases to confirm this.

Distribution of p53 alterations in a case of gliomatosis cerebri.

Gliomatosis cerebri (GC) is a rare neuroepithelial tumor characterized by diffuse infiltration of large parts of the brain. The origin of GC is unknown, and the molecular alterations underlying this tumor have not been determined. Because mutations in the p53 tumor-suppressor gene are frequent in common gliomas, we investigated the distribution of p53 alterations by immunohistochemistry and direct sequencing in a GC case with a disease involving both hemispheres and the basal ganglia. Nuclear accumulation of p53 protein was detected in a single region with features of a high-grade glioma. In the remaining 10 regions, corresponding to low-grade gliomas, no p53 accumulation was seen. In 1 low-grade tumor sample, a pathogenic splice site mutation was detected. These findings suggest that p53 alterations occur in GC, but are no prerequisite of malignant progression. The distribution of p53 alterations demonstrates the existence of topographically different clones in 1 patient.

Leptomeningeal dissemination in children with progressive low-grade neuroepithelial tumors.

Our purpose is to describe the incidence and clinical features of leptomeningeal dissemination (LM) in children with progressive low-grade neuroepithelial tumor (LGN). We have continuously tracked all patients with primary CNS tumors since 1986. Satisfactorily followed data were obtained on 427 of the 588 patients with localized LGN at diagnosis between 1986 and 1998, 177 (42%) of whom developed progressive or recurrent disease. LM was identified in 13/177 (7%). The median age at initial diagnosis was 5 years and at LM diagnosis was 8.5 years. The primary tumor sites were diencephalon (6), brainstem (3), cerebellum (2), cerebrum (1), and spinal cord (1). The histologies were pilocytic astrocytoma (4), ganglioglioma (4), fibrillary astrocytoma (3), mixed glioma (1), and glioneurofibroma (1). Management included chemotherapy (2) or radiotherapy (3) or both (7); 1 patient received only radical resections of symptomatic lesions. The 5-year progression-free survival rates for patients with localized versus LM disease at recurrence were 22% (95% confidence interval [CI], 13%-25%) versus 15% (95% CI, 0.1%-36%), respectively ( P = 0.28). The 5- and 10-year overall survival rates for patients with localized disease versus LM were 87% (95% CI, 82%-92%) and 83% (95% CI, 77%-89%) versus 68% (95% CI, 39%-91%) and 68% (95% CI, 39%-91%), respectively ( P = 0.05). The 7% incidence of LM is a low estimate because patients were not routinely staged at recurrence. Tumors arising from the diencephalon appeared to predispose to LM; no other predisposing features were identified. We strongly urge that for optimum treatment planning all patients with recurrent LGN be staged with an enhanced spine and brain MRI before adjuvant therapy is initiated. The good survival of patients with LGN and LM reflects a more indolent disease than malignant CNS tumors with LM.

Tumor neuroectodérmico primitivo: neuroepitelioma periférico / Primitive neuroectodermal tumor of the chest wall

Presentamos un paciente de sexo masculino, de 29 años de edad, que consultó por tumoración dolorosa de pared toracoabdominal derecha. Los estudios por imágenes sugieren como diagnóstico diferencial: tumor de askin (neuroepitelioma), teniendo en cuenta sus características morfológicas y topográficas. Mediante el estudio anatomopatológico y con inmunohistoquímica se confirmó el diagnóstico de neuroepitelioma primitivo (AU)

Tumor neuroectodérmico primitivo: neuroepitelioma periférico / Primitive neuroectodermal tumor of the chest wall

Presentamos un paciente de sexo masculino, de 29 años de edad, que consultó por tumoración dolorosa de pared toracoabdominal derecha. Los estudios por imágenes sugieren como diagnóstico diferencial: tumor de askin (neuroepitelioma), teniendo en cuenta sus características morfológicas y topográficas. Mediante el estudio anatomopatológico y con inmunohistoquímica se confirmó el diagnóstico de neuroepitelioma primitivo

Parotid gland metastases of two uncommon neoplasms with low metastatic potential.

Oligodendrogliomas are uncommon intracranial glial tumours in which extracranial spread is only rarely reported. Similarly, both intracranial and ocular medulloepitheliomas are also rare, with metastatic spread from the ocular neoplasm being less common than its intracranial counterpart. We report cases of an intracranial oligodendroglioma and an ocular medulloepithelioma both of which metastasised to the parotid gland. To our knowledge these are only the second oligodendroglioma and the third ocular medulloepithelioma to be reported as metastasising to this site.