Elevated chorionic gonadotropic hormone in transgenic mice induces parthenogenetic activation and ovarian teratomas

Both male and female reproductive functions are impacted by altered gonadotrophin secretion and action, which may also influence the development of endocrine tumours. To ascertain if chronic hypersecretion of human chorionic gonadotropin (hCG) contributes to the development of gonadal tumours, double transgenic (TG) mice that overexpress hCGα- and β-subunits were analysed. By the age of two months, ovarian tumours with characteristics of teratomas developed with 100% penetrance. Teratomas were also seen in wild-type ovaries orthotopically transplanted into TG mice, demonstrating an endocrine/paracrine mechanism for the hCG-induced ovarian tumorigenesis. Both in vitro and in vivo experiments showed oocyte parthenogenetic activation in TG females. In addition, ovaries showed reduced ovulatory gene expression, inhibited ERK1/2 phosphorylation, and impaired cumulus cell expansion. Hence, persistently high endocrine hCG activity causes parthenogenetic activation and development of ovarian teratomas, along with altered follicle development and impaired ERK1/2 signalling, offering a novel mechanism associated with the molecular pathogenesis of ovarian teratomas.

Endoscopic Endonasal Transsphenoidal Surgery for Intrasellar Mixed Germ Cell Tumors

A mixed germ cell tumor (MGCT) in the neurohypophysis is very rare, with only a few reported cases1-4 but none with surgical videos. In this report, the endoscopic endonasal transsphenoidal approach for MGCT in the neurohypophysis is presented (Video 1). A 12-year-old girl with ocular pain, fatigue, and nausea presented with gradual onset of quadrant hemianopsia and left oculomotor palsy. Magnetic resonance imaging showed an enhanced mass in the sella turcica with multiple components involving the pituitary gland and stalk. Her endocrinological examination showed decreased levels of pituitary hormones and simultaneously elevated serum levels of alpha-fetoprotein and beta-human chorionic gonadotropin. After pituitary hormone replacement, endoscopic endonasal transsphenoidal surgery was planned. The tumor was strongly adherent to the surrounding structures, and gross total resection was achieved. The histological diagnosis was MGCT with a teratoma component. Postoperatively, her vision and oculomotor palsy improved swiftly, and adjuvant chemotherapy and radiotherapy were administered. In this case, 3-dimensional computer graphics were created from the preoperative computed tomography and magnetic resonance imaging studies. Preoperative simulation with the 3-dimensional computer graphic images and intraoperative verification with indocyanine green images facilitated our understanding of the surrounding anatomy, including the tumor components, pituitary gland, and internal carotid arteries.5 After removal of the tumor, multilayer fascial closure was performed for skull base reconstruction.6 MGCT in the neurohypophysis can be strongly adherent to the surrounding structures, requiring careful dissection and resection under endoscopy. At the last follow-up (8 months after surgery), the tumor was successfully controlled, and the patient had no neurological symptoms with pituitary hormone replacement therapy.

Management of ruptured ovarian teratoma mimicking advanced ovarian cancer

•Chronic chemical peritonitis caused by spontaneous rupture of a mature cystic teratoma may result in prolonged hospitalization and respiratory decline and can mimic a gynecologic malignancy.•Earlier surgical intervention for mature teratoma may prevent morbidity.•Inclusion of a gynecologic oncologist is advised for management discussions and/or surgical back-up.•Complex benign gynecologic surgeries may have some benefit for gynecologic oncologic trainees, which can be used for later oncologic cases.

Unilateral Periorbital Swelling in a Pediatric Patient

Infratemporal fossa (ITF) tumors are rare in children and may present with a variety of symptoms. Teratomas are neoplasms derived from the 3 germ layers and approximately 6% to 10% are within the head and neck. Our study discusses one of the first reported cases of teratoma in the ITF in a pediatric patient. A 3-year-old girl presents with 2 years of recurrent monthly left periorbital swelling accompanied by fevers, skin discoloration, and pain. Prior episodes were treated with antibiotics with incomplete resolution. Imaging revealed a cystic lesion centered in the ITF. She was taken for endoscopic endonasal biopsy of the lesion and had no complications. Pathology revealed a mature teratoma composed primarily of pancreatic tissue. Providers should consider masses such as teratoma in the differential for ITF tumors and periorbital edema unresponsive to typical treatment.

Impact of teratoma on survival probabilities of patients with metastatic non-seminomatous germ cell cancer: Results from the IGCCCG Update Consortium

AIMS

To resolve the ongoing controversy surrounding the impact of teratoma (TER) in the primary among patients with metastatic testicular non-seminomatous germ-cell tumours (NSGCT).

PATIENTS AND METHODS

Using the International Germ Cell Cancer Collaborative Group (IGCCCG) Update Consortium database, we compared the survival probabilities of patients with metastatic testicular GCT with TER (TER) or without TER (NTER) in their primaries corrected for known prognostic factors. Progression-free survival (5y-PFS) and overall survival at 5 years (5y-OS) were estimated by the Kaplan-Meier method.

RESULTS

Among 6792 patients with metastatic testicular NSGCT, 3224 (47%) had TER in their primary, and 3568 (53%) did not. In the IGCCCG good prognosis group, the 5y-PFS was 87.8% in TER versus 92.0% in NTER patients (p = 0.0001), the respective 5y-OS were 94.5% versus 96.5% (p = 0.0032). The corresponding figures in the intermediate prognosis group were 5y-PFS 76.9% versus 81.6% (p = 0.0432) in TER and NTER and 5y-OS 90.4% versus 90.9% (p = 0.8514), respectively. In the poor prognosis group, there was no difference, neither in 5y-PFS [54.3% in TER patients versus 55.4% (p = 0.7472) in NTER], nor in 5y-OS [69.4% versus 67.7% (p = 0.3841)]. NSGCT patients with TER had more residual masses (65.3% versus 51.7%, p < 0.0001), and therefore received post-chemotherapy surgery more frequently than NTER patients (46.8% versus 32.0%, p < 0.0001).

CONCLUSION

Teratoma in the primary tumour of patients with metastatic NSGCT negatively impacts on survival in the good and intermediate, but not in the poor IGCCCG prognostic groups.

MRI findings of malignant transformation arising from mature cystic teratoma of the ovary: comparison with benign mature cystic teratoma

OBJECTIVE

This study aimed to evaluate the efficacy of MRI findings to differentiate malignant transformation arising from mature cystic teratoma (MT-MCT) of the ovary from benign mature cystic teratoma (BMCT).

MATERIALS AND METHODS

This study included 11 patients with histopathologically proven MT-MCT and 50 with BMCT. Overall, 7 patients with MT-MCT and all 50 with BMCT underwent unenhanced and contrast-enhanced MRIs and 4 with MT-MCT only underwent unenhanced MRIs. The MRI findings were evaluated and compared between the two diseases.

RESULTS

The median age (55 vs. 38 years, p < 0.01) and maximum diameter (109 vs. 65 mm, p < 0.01) were higher in MT-MCT than in BMCT. Fat component occupancy was lower in MT-MCT than in BMCT (median, 5% vs. 63%, p < 0.01). Only MT-MCT exhibited irregular tumor margins (64%), peritoneal dissemination (18%), and abnormal ascites (27%). The solid components were more commonly observed in MT-MCT than in BMCT (100% vs. 32%, p < 0.01) on contrast-enhanced images. The maximum diameter of solid components in MT-MCT was larger than that in BMCT (median, 61 mm vs. 14 mm, p < 0.01). In MT-MCT, the common configuration of solid components was endophytic or exophytic sessile (85%), whereas in BMCT, it was endophytic papillary (88%).

CONCLUSION

Compared with BMCT, MT-MCT demonstrated a larger maximum diameter, lower occupancy rate of fat components, and sessile solid components. The characteristic configuration of solid components was endophytic or exophytic sessile in MT-MCT and endophytic papillary in BMCT.

Evolution of Surgical Management of Pineal Region Tumors in the Pediatric Population: A 17-Year Experience at a Single Institution

INTRODUCTION

Pineal region tumors have historically been challenging to treat. Advances in surgical techniques have led to significant changes in care and outcomes for these patients, and this is well demonstrated by our single institution's experience over a 17-year-period in which the evolution of diagnosis, treatment, and outcomes of pineal tumors in pediatric patients will be outlined.

METHODS

We retrospectively collected data on all pediatric patients with pineal region lesions treated with surgery at Children's National Hospital (CNH) from 2005 to 2021. Variables analyzed included presenting symptoms, presence of hydrocephalus, diagnostic and surgical approach, pathology, and adverse events, among others. IRB approval was obtained (IRB: STUDY00000009), and consent was waived due to minimal risk to patients included.

RESULTS

A total of 43 pediatric patients with pineal region tumors were treated during a 17-year period. Most tumors in our series were germinomas (n = 13, 29.5%) followed by pineoblastomas (n = 10, 22.7%). Twenty seven of the 43 patients (62.8%) in our series received a biopsy to establish diagnosis, and 44.4% went on to have surgery for resection. The most common open approach was posterior interhemispheric (PIH, transcallosal) - used for 59.3% of the patients. Gross total resection was achieved in 50%; recurrence occurred in 20.9% and mortality in 11% over a median follow-up of 47 months. Endoscopic third ventriculostomy (ETV) was employed to treat hydrocephalus in 26 of the 38 patients (68.4%) and was significantly more likely to be performed from 2011 to 2021. Most (73%) of the patients who received an ETV also underwent a concurrent endoscopic biopsy. No difference was found in recurrence rate or mortality in patients who underwent resection compared to those who did not, but complications were more frequent with resection. There was disagreement between frozen and final pathology in 18.4% of biopsies.

CONCLUSION

This series describes the evolution of surgical approaches and outcomes over a 17-year-period at a single institution. Complication rates were higher with open resection, reinforcing the safety of pursuing endoscopic biopsy as an initial approach. The most significant changes occurred in the preferential use of ETVs over ventriculoperitoneal shunts. Though there has been a significant evolution in our understanding of and treatment for these tumors, in our series, the outcomes for these patients have not significantly changed over that time.

Simultaneous spine extradural and intradural teratomas in a pediatric patient: A rare presentation with insights in the flawed migration of germ cells theory

Spinal teratomas are infrequent lesions in the pediatric population. These lesions can be extradural, intradural or intramedullary. We present a case of an 8-month-old boy that was assessed for underdevelopment of motor milestones. The neurologic examination revealed hyporeflexia, decreased sensation and flaccid paraplegia. MRI of the spine revealed two simultaneous and independent lesions in the extradural and intradural compartment. A laminectomy was performed for the T4-T7 vertebrae with total resection of both lesions. The histopathological analysis confirmed both lesions to be mature cystic teratomas. At the 1-year follow-up, the patient remained with no recovery of neurological function. A debate takes place regarding the etiology of formation of these lesions in the spine. The simultaneous presentation of two independent lesions in this patient could contribute to define the flawed migration of germ cells theory as the etiology for formation of teratomatous lesions in the spine.

Mature Cystic Oral Teratoma in a Neonate- A Case Report

BACKGROUND

Neonatal oral cavity masses present complex diagnostic and management challenges, often involving respiratory distress. We present a case of a 1-day-old male neonate with an oral cavity mass and respiratory distress, whose antenatal scan revealed polyhydramnios and a nasopalatine cyst.

CASE REPORT

Clinical examination revealed a 5 * 5 cm cystic swelling arising from the right hard palate. CT scans confirmed an intraoral cystic lesion with a complete cleft palate and excluded oropharyngeal/neck extension. Aspiration of cystic fluid facilitated surgical excision, leading to a histopathological diagnosis of mature cystic teratoma. Primary closure of the soft palate defect was performed. Histopathological examination revealed it to be mature cystic teratoma.

CONCLUSION

This case underscores the intricate interplay between antenatal imaging, clinical assessment, and surgical intervention in managing neonatal oral cavity masses. The successful excision and histopathological confirmation of a mature cystic teratoma highlights the significance of accurate diagnosis and timely intervention. The complexities surrounding neonatal oral cavity masses necessitate a comprehensive approach to optimize patient outcomes.

Imaging features of mucinous carcinoma arising from mature teratoma showing cytokeratin 7+ and cytokeratin 20+ expression profile: A case report

Ovarian mature teratomas are benign, but malignant transformation can occur infrequently, especially in women of advanced age. The tissue that undergoes malignant change is mostly squamous cell carcinoma, although adenocarcinoma has been reported in a small number of cases. The immunostaining results of adenocarcinoma usually show a cytokeratin (CK)7-/CK20+ expression profile, corresponding to lower gastrointestinal tract origin. In this report, we describe a case of mucinous carcinoma arising from an ovarian mature teratoma showing a CK7+/CK20+ profile and discuss its imaging features. A 40-year-old woman presented to her primary care physician with abdominal distension and poor oral intake, and she was referred to our hospital. She had been diagnosed with an ovarian mature teratoma at our institution 3 years earlier. At the current presentation, pelvic magnetic resonance imaging showed a large multilocular cystic mass with adipose tissue extending into the upper abdomen. Densely packed cysts were observed inside the mass, which showed weak contrast enhancement on contrast-enhanced imaging and a mildly high signal on diffusion-weighted imaging. A portion of the cysts also showed abnormal 18F-fluorodeoxyglucose uptake (maximum standardized uptake value, 13.2) on positron emission tomography/computed tomography. The patient was subsequently diagnosed with mucinous carcinoma showing a CK7+/CK20+ profile arising from a mature teratoma by pathologic examination. This mucinous carcinoma arising from a mature teratoma showed a CK7+/CK20+ profile and took the form of densely packed multilocular cysts. In this respect, it was similar to primary ovarian epithelial mucinous carcinoma on both magnetic resonance imaging and pathologic examination despite showing a much higher maximum standardized uptake value than that of primary ovarian mucinous carcinoma. When a large ovarian teratoma contains a large multilocular cyst, the presence of densely packed multilocular cysts should not be missed even in a mass without solid components. Clinicians should consider the possibility of mucinous carcinoma showing a CK7+/CK20+ profile arising from a mature teratoma in such cases.

Infantile fetiform abdominal mass: Teratoma or fetus in fetu? A case report with insights into radiological diagnosis and surgical management

Fetus-in-fetu (FIF) is a rare congenital anomaly in which a malformed parasitic twin develops within the body of a live fetus or child. Abdominal teratoma, a type of germ cell tumor, can be a great imaging mimicker of FIF and vice-versa, as they both can present as a heterogeneous mass with calcifications and a fat component. Radiological differentiation of these 2 entities should be made because of the difference in surgical planning and treatment options. Features such as visualization of distinct bony vertebral elements and encysted cystic components are the specific features of Fetus in fetu [1]. In contrast, the presence of elevated serum markers can help diagnose teratoma. Here, we report a case of a 5-month-old girl presented with progressive distension of the upper abdomen for the last 2 months, noticed by her mother. Her initial imaging with abdominal X-ray and ultrasonography showed the presence of a large heterogenous solid-cystic mass in the upper abdomen with large elongated calcifications. A provisional diagnosis of teratoma vs FIF was considered. CECT abdomen showed clear identification of osseous structures of the axial and appendicular skeleton within a fat density mass, along with an encapsulated cystic component, strongly suggestive of FIF. Her serum tumor markers were within normal limits. The final diagnosis of FIF was confirmed on Laparotomy and postoperative specimens.

Immature Teratoma of Ethmoid Sinus Masquerading as Antrochoanal Polyp: A Rare Case Report with Literature Review

Teratomas are rare neoplasms that arise from totipotent stem cells. Teratomas of the head and neck are extremely rare, constituting about 10% of all cases and usually present in the neonatal period. Extensive literature search has shown that there are only two cases reportedof teratoma of the ethmoid sinus; one as a mature teratoma in a neonate and another was histologically immature teratoma in an adult male (Mwang'ombe et al. in East Afr Med J 79(2):106-107, 2002; Aggarwal et al. in J Postgrad Med 59(2):138-141, 2013). We hereby report the second case of immature teratoma of ethmoid sinus origin in an adult male.

Assessing the risk to develop a growing teratoma syndrome based on molecular and epigenetic subtyping as well as novel secreted biomarkers

In germ cell tumors (GCT), a growing teratoma during chemotherapy with decreasing tumor markers was defined as 'growing teratoma syndrome' (GTS) by Logothetis et al. in 1982. So far, its pathogenesis and specific treatment options remain elusive. We aimed at updating the GTS definition based on molecular and epigenetic features as well as identifying circulating biomarkers. We selected 50 GTS patients for clinical characterization and subsequently 12 samples were molecularly analyzed. We further included 7 longitudinal samples of 2 GTS patients. Teratomas (TER) showing no features of GTS served as controls. GTS were stratified based on growth rates into a slow (<0.5 cm/month), medium (0.5-1.5) and rapid (>1.5) group. By analyzing DNA methylation, microRNA expression and the secretome, we identified putative epigenetic and secreted biomarkers for the GTS subgroups. We found that proteins enriched in the GTS groups compared to TER were involved in proliferation, DNA replication and the cell cycle, while proteins interacting with the immune system were depleted. Additionally, GTSrapid seem to interact more strongly with the surrounding microenvironment than GTSslow. Expression of pluripotency- and yolk-sac tumor-associated genes in GTS and formation of a yolk-sac tumor or somatic-type malignancy in the longitudinal GTS samples, pointed at an additional occult non-seminomatous component after chemotherapy. Thus, updating the Logothetis GTS definition is necessary, which we propose as follows: The GTS describes a continuously growing teratoma that might harbor occult non-seminomatous components considerably reduced during therapy but outgrowing over time again.

Occipital dermal sinus associated with infectious teratoma in an adult patient affected by Klippel-Feil syndrome: Rare case report and literature review

Background

The Klippel-Feil syndrome (KFS) is a rare congenital anomaly characterized by the fusion of cervical vertebrae, which may be associated with other malformations, such as dermoid tumors and teratoma. Some theories explain the embryology of these associations. Another condition that may be present is the dermal sinus (DS), communication between intracranial tumors and the subcutaneous tissue, and predisposing infections. This case report aims to describe an association between these three pathologies as well as correlate them from the literature. This report was based on medical records retrospectively reviewed associated with the systematic bibliographical consultation using indexed databases based on inclusion and exclusion methods.

Case Description

An adult male patient, 24 years old, was admitted to our service, presenting fever and meningeal irritation as initial symptoms. In the patient's clinical history, he was diagnosed with an occipital DS in his childhood, which was previously instructed to be operated on by another neurosurgical team, but the patient chose not to perform the procedure. The magnetic resonance imaging investigation showed a DS associated with a cerebellar infected mass with 2 cm on its main diameter. The patient was treated with preoperative antibiotic therapy and underwent gross total surgical resection of the tumor as well as DS correction, confirmed in the histopathological examination as a teratoma. After surgery, further computed tomography scan analysis showed the presence of cervical vertebrae fusion, compatible with KFS diagnosis.

Conclusion

The association between KFS, cerebellar teratoma, and DS has not yet been described in the literature, with only the association of the first two being extremely rare.

Non-invasive differential diagnosis of teratomas from other intracranial germ cell tumours using MRI-based fractal and radiomic analyses

OBJECTIVES

The histologic subtype of intracranial germ cell tumours (IGCTs) is an important factor in deciding the treatment strategy, especially for teratomas. In this study, we aimed to non-invasively diagnose teratomas based on fractal and radiomic features.

MATERIALS AND METHODS

This retrospective study included 330 IGCT patients, including a discovery set (n = 296) and an independent validation set (n = 34). Fractal and radiomic features were extracted from T1-weighted, T2-weighted, and post-contrast T1-weighted images. Five classifiers, including logistic regression, random forests, support vector machines, K-nearest neighbours, and XGBoost, were compared for our task. Based on the optimal classifier, we compared the performance of clinical, fractal, and radiomic models and the model combining these features in predicting teratomas.

RESULTS

Among the diagnostic models, the fractal and radiomic models performed better than the clinical model. The final model that combined all the features showed the best performance, with an area under the curve, precision, sensitivity, and specificity of 0.946 [95% confidence interval (CI): 0.882-0.994], 95.65% (95% CI: 88.64-100%), 88.00% (95% CI: 77.78-96.36%), and 91.67% (95% CI: 78.26-100%), respectively, in the test set of the discovery set, and 0.944 (95% CI: 0.855-1.000), 85.71% (95% CI: 68.18-100%), 94.74% (95% CI: 83.33-100%), and 80.00% (95% CI: 58.33-100%), respectively, in the independent validation set. SHapley Additive exPlanations indicated that two fractal features, two radiomic features, and age were the top five features highly associated with the presence of teratomas.

CONCLUSION

The predictive model including image and clinical features could help guide treatment strategies for IGCTs.

CLINICAL RELEVANCE STATEMENT

Our machine learning model including image and clinical features can non-invasively predict teratoma components, which could help guide treatment strategies for intracranial germ cell tumours (IGCT).

KEY POINTS

• Fractals and radiomics can quantitatively evaluate imaging characteristics of intracranial germ cell tumours. • Model combing imaging and clinical features had the best predictive performance. • The diagnostic model could guide treatment strategies for intracranial germ cell tumours.

Primary testicular teratoid Wilms tumor in a 40-year-old male with retroperitoneal lymph node involvement: A case report

We report a 40-year-old male presenting with right testicular pain. Following right orchiectomy demonstrating pT1bS0N0M0 teratoma with extensive necrosis, the patient opted for surveillance. With new retroperitoneal lymphadenopathy, the patient underwent a robotic-assisted laparoscopic retroperitoneal lymph node. After final pathology demonstrated extensive necrosis, the initial orchiectomy specimen was re-reviewed which revealed 60/40 ratio of non-seminomatous teratoma to nephroblastoma. Adult presentation of testicular nephroblastoma is exceedingly rare and such reports contribute to the understanding of adult teratoid Wilms tumor pathogenesis. This case emphasizes the need for comprehensive diagnostic approaches and further research into the pathophysiology of extrarenal teratoid Wilms tumors.

Prolonged survival after thoracic metastasectomy in patients with nonseminomatous testicular cancer

INTRODUCTION

Almost 20 % of patients with Non-Seminomatous Germinative Cell Tumors (NSGCT) will require intrathoracic metastasectomy after chemotherapy. The authors aim to determine their long-term survival rates.

METHODS

Retrospective study including patients with NSGCT and intrathoracic metastasis after systemic therapy from January 2011 to June 2022. Treatment outcomes and overall survival were analyzed with the Kaplan-Meier method.

RESULTS

Thirty-seven male patients were included with a median age of 31.8 years. Six presented with synchronous mediastinum and lung metastasis, nine had only lung, and 22 had mediastinal metastasis. Over half had retroperitoneal lymph node metastasis. Twenty-two had dissimilar pathologies, with a discordance rate of 62 %. Teratoma and embryonal carcinoma were the prevalent primary tumor types, 40.5 % each, while teratoma was predominant (70.3 %) in the metastasis group. Thoracotomy was the main surgical approach (39.2 %) followed by VATS (37.2 %), cervico-sternotomy (9.8 %), sternotomy (5.8 %), and clamshell (3.9 %). Lung resection was performed in 40.5 % of cases. Overall, 10-year survival rates were 94.3 % with no surgical-related mortality.

CONCLUSION

Multimodality treatment with systemic therapy followed by radical surgery offers a high cure rate to patients with intrathoracic metastatic testicular germ cell tumors.

Testicular Radiomics To Predict Pathology At Time of Postchemotherapy Retroperitoneal Lymph Node Dissection for Nonseminomatous Germ Cell Tumor

INTRODUCTION

Testicular germ cell tumors are the most common malignancy in young adult males. Patients with metastatic disease receive standard of care chemotherapy followed by retroperitoneal lymph node dissection for residual masses >1cm. However, there is a need for better preoperative tools to discern which patients will have persistent disease after chemotherapy given low rates of metastatic germ cell tumor after chemotherapy. The purpose of this study was to use radiomics to predict which patients would have viable germ cell tumor or teratoma after chemotherapy at time of retroperitoneal lymph node dissection.

PATIENTS AND METHODS

Patients with nonseminomatous germ cell tumor undergoing postchemotherapy retroperitoneal lymph node dissection (PC-RPLND) between 2008 and 2019 were queried from our institutional database. Patients were included if prechemotherapy computed tomography (CT) scan and postchemotherapy imaging were available. Semiqualitative and quantitative features of residual masses and nodal regions of interest and radiomic feature extractions were performed by 2 board certified radiologists. Radiomic feature analysis was used to extract first order, shape, and second order statistics from each region of interest. Post-RPLND pathology was compared to the radiomic analysis using multiple t-tests.

RESULTS

45 patients underwent PC-RPLND at our institution, with the majority (28 patients) having stage III disease. 24 (53%) patients had teratoma on RPLND pathology, while 2 (4%) had viable germ cell tumor. After chemotherapy, 78%, 53%, and 33% of patients had cystic regions, fat stranding, and local infiltration present on imaging. After radiomic analysis, first order statistics mean, median, 90th percentile, and root mean squares were significant. Strong correlations were observed between these 4 features;a lower signal was associated with positive pathology at RPND.

CONCLUSIONS

Testicular radiomics is an emerging tool that may help predict persistent disease after chemotherapy.

Anti-N-methyl-D-aspartate receptor-associated encephalitis: A review of clinicopathologic hallmarks and multimodal imaging manifestations

Anti-N-methyl-D-aspartate receptor-associated encephalitis (NMDARE) is a rare immune-mediated neuroinflammatory condition characterized by the rapid onset of neuropsychiatric symptoms and autonomic dysfunction. The mechanism of pathogenesis remains incompletely understood, but is thought to be related to antibodies targeting the GluN1 subunit of the NMDA receptor with resultant downstream dysregulation of dopaminergic pathways. Young adults are most frequently affected; the median age at diagnosis is 21 years. There is a strong female predilection with a female sex predominance of 4:1. NMDARE often develops as a paraneoplastic process and is most commonly associated with ovarian teratoma. However, NMDARE has also been described in patients with small cell lung cancer, clear cell renal carcinoma, and other benign and malignant neoplasms. Diagnosis is based on correlation of the clinical presentation, electroencephalography, laboratory studies, and imaging. Computed tomography, positron emission tomography, and magnetic resonance imaging are essential to identify an underlying tumor, exclude clinicopathologic mimics, and predict the likelihood of long-term functional impairment. Nuclear imaging may be of value for prognostication and to assess the response to therapy. Treatment may involve high-dose corticosteroids, intravenous immunoglobulin, and plasma exchange. Herein, we review the hallmark clinicopathologic features and imaging findings of this rare but potentially devastating condition and summarize diagnostic criteria, treatment regimens, and proposed pathogenetic mechanisms.

Mature cystic teratoma overlapping with giant serous cystadenoma of the ovary: A case report

Ovarian lesions represent a diagnostic challenge for the radiologist and should be approached according to the patient's age, menstrual cycle, and imaging characteristics. These lesions can be cystic, mixed, or solid-predominant structures. Generally, the occurrence of benign lesions surpasses that of malignant ones at a ratio of 3:1. However, within infantile and juvenile age groups, this becomes an infrequent occurrence, making up only about 5% of ovarian tumor cases. This case report sheds light on a unique scenario involving a pediatric patient who harbored 2 benign tumors simultaneously: a mature cystic teratoma and a serous cystadenoma.

[Low-grade astrocytoma within a retroperitoneal teratoma: Case report]

Teratomas are neoplasms originate from germ cells and can undergo malignant transformation, the World Health Organization (WHO) classified them as teratoma with somatic-type malignancy which is uncommon and sarcomas are the histological type with the highest incidence. It is important to identify this type of tumors because influences the prognosis and survival of the patient. We present the case of a 5-month-old male, who began his condition at one month-old with constipation and increase of the abdominal circumference, imaging studies revealed an abdominal lesion, he was treated with chemotherapy and surgery. The histopathological report was immature teratoma, grade 1, with a focus of nervous tissue showing characteristics of low-grade astrocytoma.

PET/CT Examination of Teratomas after Stem Cell Transplantation for a Spinal Cord Injury: A Case Report

BACKGROUND

In clinical practice, stem cell transplantation has become an effective method for treating spinal cord nerve injury. Up to now, there has been no report on teratoma caused by transplanted stem cell's abnormal differentiation in the clinic, especially in the analysis of imaging manifestations. Therefore, this article aims to analyze the PET/CT imaging manifestations of teratoma caused by stem cell transplantation to improve the imaging diagnosing capability.

CASE PRESENTATION

A patient with a spinal cord injury who had received a stem cell transplant was examined by PET/CT on September 10th, 2020. The PET/CT images of the lesion showed irregular mixed low density on the right side of the erector spinae muscle area at the level of the cervical 3-5 vertebral body, with a maximum cross-section of 9.1×3.9 cm. The 18F-FDG metabolism of the lesion was increased, and the maximum standard uptake value (SUVmax) was 10.7. The boundary was unclear with the third cervical vertebra and cervical 3 and 4-level vertebral plates. Based on the patient's medical history, the lesion was diagnosed as an abnormal proliferative tumor, which was consistent with the pathological examination results.

CONCLUSION

To date, there have been no clinical reports on teratomas caused by stem cell transplantation for spinal cord injury at home or abroad. This case report enhances the knowledge of the diagnosis and treatment methods of this type of disease and confirms the diagnostic value of PET/CT examination.

[Ovarian masses in infants and children]

BACKGROUND

Abnormalities of the ovary are frequently seen on ultrasound examination, sometimes symptomatic, but are more commonly asymptomatic.

PURPOSE

Presentation of the most important entities of ovarian masses and their imaging features in infants and children. Discussion of criteria for differentiation between benign and potentially malignant masses.

MATERIALS AND METHODS

Review of current literature and presentation of image examples.

RESULTS

The most common lesions are ovarian cysts in infants, which usually do not require therapy. Because of the risk of torsion, surgery should be discussed for lesions with a size of 5 cm or more. Benign teratomas represent three-quarters of all solid tumors of the infantile ovary. Malignant masses are rare. The task of imaging is to assess the potential risk of malignancy, also using imaging scores.

CONCLUSIONS

Imaging plays a crucial role for therapeutic considerations. Depending on the potential risk, ovarian-sparing surgery is preferred to preserve fertility, as long as the oncologic risk is reasonable.

Anesthetic Care During Exploratory Laparotomy and Excision of a Fetus-in-Fetu With a Combined General-Regional Anesthetic Technique Using a Caudal Epidural Catheter

Fetus-in-fetu (FIF) is a rare, congenital anomaly involving the presence of one of a pair of twins within the body of the other. It is postulated that this pathology occurs during embryogenesis of a diamniotic-monochorionic twin pregnancy with unequal division of the blastocele, which results in monozygotic, monochorionic, and diamniotic twins of unequal sizes. Presentation as an abdominal mass during the neonatal period or infancy is most common, although late diagnosis during the adult years may also occur. We report a 1-day-old, full-term female neonate who presented for exploratory laparotomy and excision of a FIF. We present the use of a combined general-regional technique using caudal epidural anesthesia. The etiology, presentation, appropriate workup, and treatment of FIF are presented. Previous anecdotal reports of anesthetic care for excision of FIF are reviewed.