Defining the Teratoma as a Model for Multi-lineage Human Development.

We propose that the teratoma, a recognized standard for validating pluripotency in stem cells, could be a promising platform for studying human developmental processes. Performing single-cell RNA sequencing (RNA-seq) of 179,632 cells across 23 teratomas from 4 cell lines, we found that teratomas reproducibly contain approximately 20 cell types across all 3 germ layers, that inter-teratoma cell type heterogeneity is comparable with organoid systems, and teratoma gut and brain cell types correspond well to similar fetal cell types. Furthermore, cellular barcoding confirmed that injected stem cells robustly engraft and contribute to all lineages. Using pooled CRISPR-Cas9 knockout screens, we showed that teratomas can enable simultaneous assaying of the effects of genetic perturbations across all germ layers. Additionally, we demonstrated that teratomas can be sculpted molecularly via microRNA (miRNA)-regulated suicide gene expression to enrich for specific tissues. Taken together, teratomas are a promising platform for modeling multi-lineage development, pan-tissue functional genetic screening, and tissue engineering.

A rare germline BMP15 missense mutation causes hereditary ovarian immature teratoma in human.

Ovarian immature teratomas (OITs) are malignant tumors originating from the ovarian germ cells that mainly occur during the first 30 y of a female's life. Early age of onset strongly suggests the presence of susceptibility gene mutations for the disease yet to be discovered. Whole exon sequencing was used to screen pathogenic mutations from pedigrees with OITs. A rare missense germline mutation (C262T) in the first exon of the BMP15 gene was identified. In silico calculation suggested that the mutation could impair the formation of mature peptides. In vitro experiments on cell lines confirmed that the mutation caused an 84.7% reduction in the secretion of mature BMP15. Clinical samples from OIT patients also showed a similar pattern of decrease in the BMP15 expression. In the transgenic mouse model, the spontaneous parthenogenetic activation significantly increased in oocytes carrying the T allele. Remarkably, a mouse carrying the T allele developed the phenotype of OIT. Oocyte-specific RNA sequencing revealed that abnormal activation of the H-Ras/MAPK pathway might contribute to the development of OIT. BMP15 was identified as a pathogenic gene for OIT which improved our understanding of the etiology of OIT and provided a potential biomarker for genetic screening of this disorder.

Malignant ovarian and testicular germ cell tumors: Common characteristics but different prognoses.

Both ovarian and testicular germ cell tumors (GCTs) arise from the primordial germ cell and share many similarities. Both malignancies affect mainly young patients, show remarkable responsiveness to cisplatin-based therapy, and have an excellent prognosis, which also highlights the importance of minimizing long-term side effects. However, certain differences can be noted: The spreading of the disease differs, and the staging system and treatment recommendations are dissimilar. Moreover, the prognosis for ovarian GCTs is significantly inferior to that for testicular cancer, as exemplified in this review comparing the survival in Swedish patients diagnosed with testicular (1995-2022) and ovarian (1990-2018) GCTs. The 5-year overall survival in ovarian GCTs was 85.2%, versus 98.2% for testicular GCTs. How can this be explained? One reason may be the difference in knowledge, experience, and evidence because the incidence rate of testicular cancer is more than 15 times that of ovarian GCTs. Given the rarity of the disease in women and the lack of established guidelines, a comprehensive understanding of the disease and treatment decisions is challenging. The main objective of this review is to derive insights from testicular GCTs (seminoma and non-seminoma) by reviewing etiological, tumor biological, and clinical knowledge, and to thereafter suggest actions for ovarian GCTs based on this. We hypothesize that by adopting specific treatment strategies from testicular GCTs-including de-escalating adjuvant chemotherapy for low-risk patients and implementing more standardized and intensive treatment protocols in cases of relapse-we can improve the prognosis and minimize long-term side effects in ovarian GCT patients.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy to Treat Pseudomyxoma Peritonei of Ovarian Origin: A Retrospective French RENAPE Group Study.

BACKGROUND: Ovarian pseudomyxoma peritonei (OPMP) are rare, without well-defined therapeutic guidelines. We aimed to evaluate cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) to treat OPMP. METHODS: Patients from the French National Network for Rare Peritoneal Tumors (RENAPE) database with proven OPMP treated by CRS/HIPEC and with histologically normal appendix and digestive endoscopy were retrospectively included. Clinical and follow-up data were collected. Histopathological and immunohistochemical features were reviewed. RESULTS: Fifteen patients with a median age of 56 years were included. The median Peritoneal Cancer Index was 16. Following CRS, the completeness of cytoreduction (CC) score was CC-0 for 9/15 (60%) patients, CC-1 for 5/15 (33.3%) patients, and CC-2 for 1/15 (6.7%) patients. The median tumor size was 22.5 cm. After pathological review and immunohistochemical studies, tumors were classified as Group 1 (mucinous ovarian epithelial neoplasms) in 3/15 (20%) patients; Group 2 (mucinous neoplasm in ovarian teratoma) in 4/15 (26.7%) patients; Group 3 (mucinous neoplasm probably arising in ovarian teratoma) in 5/15 (33.3%) patients; and Group 4 (non-specific group) in 3/15 (20%) patients. Peritoneal lesions were OPMP pM1a/acellular, pM1b/grade 1 (hypocellular) and pM1b/grade 3 (signet-ring cells) in 13/15 (86.7%), 1/15 (6.7%) and 1/15 (6.7%) patients, respectively. Disease-free survival analysis showed a difference (p = 0.0463) between OPMP with teratoma/likely-teratoma origin (groups 2 and 3; 100% at 1, 5, and 10 years), and other groups (groups 1 and 4; 100%, 66.6%, and 50% at 1, 5, and 10 years, respectively). CONCLUSION: These results suggested that a primary therapeutic strategy using complete CRS/HIPEC for patients with OPMP led to favorable long-term outcomes.

Dermoid cyst management and outcomes: a review of over 1000 cases at a single institution.

BACKGROUND: Mature cystic teratomas represent nearly 60% of benign ovarian neoplasms across all age groups. OBJECTIVE: This study aimed to update existing descriptive studies of ovarian teratomas, including the epidemiology, rate of torsion or malignancy, and treatment modalities in a large modern cohort of patients. STUDY DESIGN: This was a retrospective cross-sectional study of all pathology-confirmed cases of ovarian teratoma that underwent surgery at 1 tertiary care institution from 2004 to 2015. Patient demographics, ovarian cyst characteristics, surgical approach and timing, rate of spillage, and surgical complications were examined. RESULTS: A total of 1054 cases of ovarian teratoma were identified during the study period. There were 113 cases (10.7%) of bilateral teratoma. The mean age at diagnosis was 38 years. The average cyst size was 6.26 cm. The overall rate of torsion was 5.6%, with a higher rate of torsion with increasing cyst size. More than 70% of cases were treated with minimally invasive surgery, which was associated with decreased perioperative complications but an increased risk of cyst spillage. Among 394 patients with cyst spillage, only 1 patient developed chemical peritonitis. The malignant transformation rate of mature cystic teratoma in this cohort was 1.1%. This cohort included 100 pregnant women with mature teratoma. Pregnant patients were more likely to have minimally invasive surgery in the first trimester of pregnancy and more likely to undergo laparotomy in the second or third trimester of pregnancy. CONCLUSION: Similar rates of bilaterality, torsion, malignant transformation, and struma ovarii in ovarian teratomas were found in this large modern cohort compared with previous literature. Most cases of ovarian teratoma can be managed laparoscopically, which is associated with a lower surgical complication rate. Despite the increased risk of cyst spillage with a minimally invasive approach, chemical peritonitis is a rare complication.

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.

Variability in Surveillance Strategies Following Resection of Sacrococcygeal Teratoma.

INTRODUCTION: Surveillance following sacrococcygeal teratoma (SCT) resection varies. The purpose of this study was to describe the clinical characteristics and outcomes of patients undergoing SCT resection and examine current institutional practices to detect recurrence. METHODS: A single-institution retrospective review of children who underwent resection of an SCT from January 1, 2010 to December 31, 2020 was performed. Data were summarized and surveillance strategies compared between histopathologic subtypes using nonparametric methods. RESULTS: Thirty six patients (75.0% female) underwent SCT removal at a median age of 8 d. Histopathology revealed 27 mature teratomas (75.0%), eight immature teratomas (22.2%), and one malignant germ cell tumor (2.8%). Median postoperative follow-up was 3.17 y (interquartile range [IQR]: 2.31-4.38 y). Patients had a median of 2.32 clinic visits per year (IQR: 2.00-2.70), alpha-fetoprotein levels were obtained at a median of 2.01 times per year (IQR: 0-1.66), and surveillance imaging was performed at a median of 2.31 times per year (IQR: 0-2.84). Patients with immature teratomas had alpha-fetoprotein laboratories obtained more frequently than patients with mature teratomas (3.10 times/year versus 0.93 times/year, P = 0.001). There was no significant difference in the number of imaging studies obtained between groups. Two patients (5.6%) developed recurrence, which were identified on magnetic resonance imaging at 191 and 104 d postresection, respectively. CONCLUSIONS: Postoperative surveillance practices varied widely. Recurrence was noted in a single malignant case in the first year following resection. Multi-institutional studies are needed to determine the optimal surveillance strategy to detect recurrence of SCT.

Impact of microscopic deposits of yolk sac tumor on recurrence of mature sacrococcygeal teratoma.

INTRODUCTION: Sacrococcygeal teratomas (SCT) with malignant histology frequently recur and are treated aggressively, but risk factors and surveillance protocols are less established for mature tumors. In particular, prior studies have not investigated whether microscopic deposits of yolk sac tumor (YST) in otherwise mature teratomas lead to higher recurrence rates. METHODS: We reviewed patients with mature SCTs resected at our institution from 2011 to 2021 and analyzed tumor characteristics, treatment, and outcomes. RESULTS: We identified 56 patients with mature SCT, of which 9 (16%) demonstrated microscopic YST. Following surgery, 7/56 (13%) patients developed local recurrence at a mean of 1.2 ± 0.7 years, while no patients developed metastases. Recurrence was more likely in patients with microscopic YST [5/9 (56%) vs. 2/47 (4%), p = 0.021] and positive margins [6/24 (35%) vs. 1/32 (3.1%), p = 0.030]. A solid tumor component tended to increase recurrence risk as well [6/29 (21%) vs. 1/27 (4%), p = 0.053]. Five patients demonstrated malignant recurrence and were all detected by a rising alpha-fetoprotein (AFP), while two patients demonstrated recurrence of mature teratoma and were detected on surveillance magnetic resonance imaging (MRI). CONCLUSIONS: Microscopic foci of YST may increase recurrence risk for patients with mature SCT. Such patients might benefit from closer postoperative surveillance with serial AFP measurements and MRI.

Growing teratoma syndrome in children and adolescents: Prevalence and surgical outcome.

INTRODUCTION: Patients affected by metastatic germ cell tumors may occasionally experience enlargement of masses with concurrent normalization of tumor markers during or after chemotherapy. This phenomenon is described as growing teratoma syndrome (GTS). The aim of the pre sent study is to assess the prevalence of GTS in the pediatric population and its implications in terms of surgical outcome. PATIENTS AND METHODS: The clinical notes of patients diagnosed with stage III and IV malignant germ cell tumors from January 2010 until December 2020 at our Institution were retrospectively reviewed. The prevalence of GTS, treatment strategies, survival, and outcome were analyzed. RESULTS: Thirty-three patients with high-stage malignant germ cell tumors were diagnosed in our institution in the analyzed period. Nine patients (28%) had radiologic evidence of enlargement of persistent masses with normal markers after chemotherapy; these patients were classified as GTS patients. All nine patients underwent resection of metastatic lymph nodes, and six had surgery on visceral metastases. In six patients, radical excision of all metastatic sites was achieved; five patients are alive and in complete remission, while one died because of peri-operative complications. Out of the three patients who could not achieve radical excision of the metastases, two died of progressive disease, and one is alive with progressive disease. CONCLUSIONS: Patients affected by GTS have a risk of progression of chemotherapy-resistant disease and death. Radical surgical excision is essential to achieve disease control and long-term survival.

Anti-NMDAR encephalitis with delayed ovarian teratoma in a young woman: a case report with 5 years of follow-up.

BACKGROUND: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune disorder with a variety of clinical manifestations. It has been established that anti-NMDAR encephalitis may be related to ovarian teratoma in female patients. However, a considerable number of patients have no obvious evidence of ovarian teratoma during the onset of the disease. CASE: A 25-year-old previously-healthy female experienced a series of acute symptoms within two days, including confusion, disorientation, short-term memory loss, auditory hallucinations, abnormal behavior, refractory status epilepticus, etc. Her brain MRI and abdominal imaging showed no definite abnormality while her electroencephalogram exhibited the presence of low to moderate amplitude sharp, spike, and multi-spike waves. Serum and cerebrospinal fluid tests yielded positive results for anti-NMDAR antibodies. However, an ultrasound scan failed to identify an ovarian teratoma. Consequently, the diagnosis of anti-NMDAR encephalitis without teratoma was made after 4 days onset. After the plasma exchange and immunoglobulin therapy, her neurological symptoms improved and obtained a clinical cure. In the next eight months of follow-up, the patient accidentally touched a lump in the lower abdomen without any symptoms, and abdominal ultrasound and CT scan revealed a left ovarian tumor. Then she underwent left ovarian teratoma resection surgery and histopathology showed a mature cystic teratoma with neural components. The patient continued to receive five years of follow-up, and her condition remained stable without any recurrence, except that there had been a low titer of anti-NMDAR antibody in her serum. CONCLUSION: Our case demonstrated the importance of long-term follow-up for female patients with anti-NMDAR encephalitis, since anti-NMDAR encephalitis-associated ovarian teratomas may develop in a delayed manner, even without any symptoms.

Growth velocity of fetal sacrococcygeal teratoma as predictor of perinatal morbidity and mortality: multicenter study.

OBJECTIVE: To identify prenatal predictors of poor perinatal outcome in fetuses with isolated sacrococcygeal teratoma (SCT). METHODS: This was a retrospective study of fetuses with isolated (non-syndromic) SCT managed at one of five pediatric surgery and/or fetal medicine centers between January 2007 and December 2017. The primary outcome was the occurrence of poor perinatal outcome, defined as prenatal death (including termination), or neonatal death or severe compromise (hemorrhagic shock). Data regarding prenatal diagnosis (sonographic features both at referral and at the last ultrasound examination before pregnancy outcome, assessment of SCT growth velocity), perinatal complications and outcome, and neonatal course were analyzed to determine prenatal SCT characteristics associated with adverse perinatal outcome. RESULTS: Fifty-five fetuses were included, diagnosed with isolated SCT at a median gestational age of 22 (interquartile range, 18-23) weeks. There was a poor perinatal outcome in 31% (n = 17) of these cases, including intrauterine fetal demise (4%, n = 2), pregnancy termination (13%, n = 7) and neonatal severe compromise (15%, n = 8), leading to neonatal death in five cases. The overall survival rate after prenatal diagnosis of isolated SCT was 75% (n = 41 of 55). Earlier gestational age at diagnosis (P = 0.02), large tumor volume at referral (P < 0.001), presence of one or more hemodynamic complications (P = 0.02), fast tumor growth velocity (P < 0.001) and high tumor grade (highest tumor grade ≥ 3) (P = 0.049) were associated with poor perinatal outcome on univariate analysis. On stepwise logistic regression analysis, tumor growth velocity was the only remaining independent factor associated with poor perinatal outcome (odds ratio (OR) (per 1-mm/week increase), 1.48 (95% CI, 1.22-1.97), P = 0.001). The best predictive cut-off of tumor growth velocity for poor perinatal outcome was 7 mm/week (OR, 25.7 (95% CI, 5.6-191.3), P < 0.001), yielding a sensitivity of 88% and a specificity of 77%. CONCLUSIONS: Approximately 30% of fetuses with a diagnosis of isolated SCT have poor perinatal outcome. Tumor growth velocity ≥ 7 mm/week appears to be an appropriate discriminative cut-off for poor perinatal outcome. These results could help to inform prenatal management and counseling of parents with an affected pregnancy. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

A rare case of retroperitoneal teratoma with evidence of papillary thyroid carcinoma: a case report.

BACKGROUND: Teratomas are germ cell tumors composed of somatic tissues from up to three germ layers. Primary retroperitoneal teratomas usually develop during childhood and are uncommon in adults and in the retroperitoneal space. While there are only a few cases of retroperitoneal thyroid tissue, we report a unique case of a retroperitoneal papillary thyroid carcinoma. CASE PRESENTATION: A 41-year-old woman presented in our institution due to intermitted unspecific abdominal pain. Magnetic resonance imaging detected a multi-cystic solid retroperitoneal mass ventral to the psoas muscle and the left iliac artery. After surgical removal of the retroperitoneal mass, histology sections of the specimen indicated evidence of papillary thyroid carcinoma cells. A staging computed tomography scan of the body showed no further manifestations. To reduce the risk of recurrence, total thyroidectomy was performed followed by radioiodine therapy with lifelong hormone substitution. CONCLUSIONS: Primary retroperitoneal teratoma with evidence of papillary thyroid carcinoma is a rare condition. Preoperative diagnosis is difficult due to its non-specific clinical manifestation and lack of specific radiologic findings. Histopathology analysis is necessary for diagnosis. Although surgery is considered the first line treatment, there is still discussion about the extent of resection and the need for total thyroidectomy with adjuvant radioiodine therapy.

Teratoma combined with struma ovarii and sarcomatoid carcinoma: a case report and review of the literature.

This is a rare case of struma ovarii combined with sarcomatoid carcinoma. Because struma ovarii and ovarian sarcomatoid carcinoma have an extremely low incidence, this may be the first case of a combined occurrence of both. Therefore, this report describes its clinical manifestations, diagnosis, and treatment, analyzes the pathogenesis, and summarizes the previous literature in the hope that it can be helpful to other tumor-related medical personnel and provide material support for the formation of guidelines for this disease.

Central nervous tissue in ovarian mature teratoma: A neuropathological study of 101 resected tumors.

Ovarian mature teratomas frequently contain central nervous system (CNS) tissue that often exhibits a variety of neuropathologic alterations. The author systematically examined the changes seen in CNS tissue from a series of 251 cases of resected ovarian mature teratomas. A total of 101 (40.2%) samples contained CNS tissue in varying amounts. The principal pathologic findings in the CNS tissue from ovarian mature teratomas were as follows: (i) CNS tissue tended to form a relatively thin, undulating, plate-like structure that comprised the walls or septa of cystic tumors; (ii) most neurons were small or medium sized, and no CD34-positive "ramifying cells" were observed; (iii) cytoplasmic processes of some astrocytes closely surrounded the walls of capillaries, suggesting formation of a blood-brain barrier; (iv) some ependymal cells exhibited a columnar shape and showed a pseudostratified arrangement, and these cells extended thick basal cytoplasmic processes into the neuropil; (v) a few choroid plexus epithelial cells showed melanin deposition, tubular transformation, or oncocytic changes; (vi) hamartoma-like hyperplasia of arachnoid cells was noted beneath skin tissue; (vii) some CNS tissue showed formation of cerebral cortical structures exhibiting "gyration" with incompletely layered structures, and disruption of the glia limitans with spillage of cortical tissue into the "subarachnoid" space was also observed; and (viii) in the well-formed cerebellar cortex, dendrites of Purkinje cells exhibited varied dysmorphic changes. These neuropathologic observations should lead to a deeper understanding of the pathogenesis of various lesions in the brain.

Nasal immature teratoma in an elderly patient: Clinicopathological and epigenetic analogies with central nervous system counterparts, alongside genomic divergences.

Germ cell tumors (GCTs) are categorized as gonadal or extra-gonadal, based on the origin. Extra-gonadal GCTs predominantly manifest within the central nervous system (CNS), mediastinum, retroperitoneum, and sacrococcygeal region. These malignancies are most frequently diagnosed in the pediatric, adolescent, and young adult demographics. Incidences of GCT within the nasal cavity are notably scarce, with only six cases documented. This report details the case of a 70-year-old man who presented with a left nasal mass ultimately diagnosed as immature teratoma. A remarkable aspect of this case was the detection of SMARCA4 (BRG1) loss through immunohistochemical analysis. In addition, methylation profiling aligned this case with CNS GCTs, specifically those classified as non-germinomatous GCTs. This molecular characterization informed a tailored therapeutic strategy incorporating carboplatin and etoposide, alongside localized irradiation. This individualized treatment regimen achieved favorable outcomes, with the patient remaining recurrence free for over three years. This highlights the need for precise therapeutic approaches in the management of extragonadal GCTs, particularly those arising in atypical anatomical locations. The present case accentuates the significance of thorough diagnostic evaluations and customized treatment plans for rare GCT presentations. Further empirical and clinical investigations are warranted to enhance our understanding of and refine therapeutic protocols for such exceptional cases.

Laparoscopic-assisted Fertility-sparing Surgery for Growing Teratoma Syndrome of the Ovary: Experience from a Tertiary Center.

STUDY OBJECTIVE: The main objective is to evaluate the feasibility of laparoscopic fertility-sparing surgery in women with growing teratoma syndrome. DESIGN: Retrospective cohort study. SETTING: Chinese tertiary university hospital. PATIENTS: Patients with growing teratoma syndrome who underwent fertility-sparing surgery between January 2015 and August 2023. INTERVENTIONS: Baseline characteristics and surgical outcomes were evaluated, including clinical information, surgical procedures, operative time, intraoperative blood loss, complications, length of hospital stay, and follow-up information. MEASUREMENT AND MAIN RESULTS: Twenty-six patients with ovarian growing teratoma syndrome underwent fertility-sparing surgery: 12 had laparoscopic surgery and 14 underwent laparotomic surgery. In the laparoscopic group, the median age of the patients during initial management of immature teratoma or mixed malignant ovarian germ cell tumor was 14.0 years (interquartile range, 13.0-24.5 years). Eleven patients were nulliparous. The primary ovarian tumor was pure immature teratoma in 10 patients and mixed ovarian germ cell tumor in 2 patients. Complete laparoscopic tumor resection was achieved in 11 patients. Patients in the laparoscopic group had shorter median operative time (76.5 vs 180.0 minutes, p = .001), lower estimated blood loss (20.0 vs 400.0 mL, p <.001), and decreased postoperative hospital stay (2.0 vs 7.0 days, p <.001) compared with laparotomic surgery. There was no conversion to laparotomy and no perioperative complications. Histologic examination confirmed mature teratoma in all cases. During a median follow-up of 21.9 months (interquartile range, 7.6-44.9 months), 11 patients were alive without disease and 1 was alive with disease. One pregnancy was achieved postoperatively. CONCLUSION: Laparoscopic fertility-sparing surgery may represent a feasible option in well-selected patients with ovarian growing teratoma syndrome. Surgery should be performed in gynecologic oncology centers by experienced staff trained in endoscopic procedures. More research and long-time follow-up are needed to determine the oncologic outcomes and safety of laparoscopic surgery in this population.

Pediatric mediastinal lymphatic malformation: misdiagnosis analysis and literature review.

OBJECTIVES: Mediastinal cystic lymphatic malformation (MCLM) in children is prone to misdiagnosis as cystic teratoma. We compared the clinical and radiologic features between the two diseases and performed a cross-comparison with previous research on adult cases. This study aims to identify characteristic pediatric manifestations to improve diagnostic accuracy. METHODS: A retrospective study of clinical and radiologic data was conducted on 12 MCLM and 20 cases of cystic teratomas confirmed by pathology or intervention biopsy. Clinical characters and radiology features (mass location and morphology, density, component, secondary complication) were recorded and compared. We reviewed clinical studies on MCLM published in the past decades, analyzing radiological differences and comparing pediatric MCLM cases at our hospital with those in the literature. RESULTS: Group comparison in pediatrics between MCLM and cystic teratomas: There were significant age differences (p = 0.036), shape (p = 0.003), CT difference value (p < 0.001), CT difference ratio (p < 0.001), calcification (p < 0.001), fat (p < 0.001), and typing (p < 0.001) between the two diseases. An analysis of literature data on MCLM cases involved 16 studies. CONCLUSION: The absence of internal fat or irregular morphology, along with a minimal CT difference value, may suggest the diagnosis of MCLM. In pediatric cases, anterior mediastinal diseases tend to extend toward the neck, and the presence of the thymus can complicate the component analysis, thereby increasing the risk of misdiagnosis. Clinical diagnosis and differential diagnosis of pediatric MCLM rely heavily on imaging evaluation.

Congenital orbital teratoma: a rare case with intracranial extension.

INTRODUCTION: Teratoma is the most common congenital tumor, but the orbital location is rare. It is composed of tissues from ectoderm, mesoderm, and endoderm. CLINICAL PRESENTATION: Congenital orbital teratoma commonly presents as unilateral proptosis, with rapid growth, leading to exposure keratopathy. DIAGNOSIS: Prenatal ultrasound may detect the orbital mass, computed tomography (CT) scans, and magnetic resonance (MR) imaging are better in demonstrating multilocular cystic and solid mass, without bone erosion. Laboratory tests should include alfa-fetoprotein (AFP) and B-human chorionic gonadotropin (B-HCG), and histopathologically, it contains all three germ cell layers components. The management is surgical removal of the lesion, the mature teratoma has a benign behavior, and the immature has a poor prognostic. We describe a rare case of congenital orbital teratoma with intracranial extension of the lesion, in which was treated with orbital exenteration. After surgery, AFP levels decreased, the middle face displacement has improved and development milestones were appropriate.

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.

Vasospasm and subsequent stroke from paraneoplastic syndrome in a pediatric patient with an intracranial mature teratoma: a case report.

Teratomas account for 18-20% of all intracranial germ cell tumors and mostly occur in the pineal region with only a few cases of pediatric sellar and suprasellar teratomas described in the literature. Here, we present a case of a child with an intracranial mature teratoma with pancreatic features causing vasospasm and subsequent stroke, found to be positive for CDKN2A-an independent variant associated with malignancy and small vessel disease leading to stroke.