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.

Genetic Profiling of Sebaceous Carcinoma Arising from an Ovarian Mature Teratoma: A Case Report.

Ovarian mature teratomas (OMTs) originate from post-meiotic germ cells. Malignant transformation occurs in approximately 1-2% of OMTs; however, sebaceous carcinoma arising from OMTs is rare. This is the first report of a detailed genomic analysis of sebaceous carcinoma arising from an OMT. A 36-year-old woman underwent evaluation for abdominal tumors and subsequent hysterectomy and salpingo-oophorectomy. Pathologically, a diagnosis of stage IA sebaceous carcinoma arising from an OMT was established. Eight months post-surgery, the patient was alive without recurrence. Immunohistochemically, the tumor was negative for mismatch repair proteins. A nonsense mutation in TP53 (p.R306*) and a deletion in PIK3R1 were identified. Single nucleotide polymorphisms across all chromosomes displayed a high degree of homozygosity, suggestive of uniparental disomy. Herein, the OMT resulting from the endoreduplication of oocytes underwent a malignant transformation to sebaceous carcinoma via TP53 as an early event and PIK3R1 as a late event.

Neuroblastoma Arising in an Immature Teratoma of the Ovary in a 13-Year-Old.

Somatic malignancies arising in mature teratomas are exceedingly rare entities and even more so are those arising in immature teratomas. Here, we present a unique case of a 13-year-old who initially underwent ovarian sparing cystectomy for a 7.7 cm left ovarian mass with a pre-operative diagnosis of mature cystic teratoma. Histologically, all 3 germ cell layers were present and immature neuroepithelial tubules were also identified. Subsequent sections revealed a nodular lesion composed of neuropil, neuroblasts with a spectrum of maturation, and Schwannian-type stroma. The neuroblasts were diffusely positive for PHOX2B. Neuroblastoma arising in an immature teratoma has only been described in the literature once previously in an adult patient.

"Floating ball sign" in the diagnostic imaging of mature ovarian teratomas in children.

The "floating ball sign" (FBS) is a rarely described visual phenomenon found in mature ovarian teratoma imaging. It is characterized by the presence of movable, spherical areas within the cystic component of a tumor. Such visualization is possible both in cross-sectional imaging and ultrasonography. To evaluate the incidence of FBS in the pediatric population with regard to patients' age and tumor size. This is a retrospective study of pediatric patients operated on in a tertiary pediatric surgical center between January 2009 and December 2022 due to mature ovarian teratoma; the medical records were reviewed for the age at diagnosis, recurrences, tumor size, and their characteristics in preoperative imaging. Eighty-three patients (mean age 14, range 0-17) out of 91 met the inclusion criteria for the analysis. Eighty-seven operations on 90 ovaries were performed. Preoperatively 38 patients underwent CT, 13 MRI, and 39 received only the ultrasound examination. The FBS was identified in preoperative imaging diagnostics in 3 (3.3%) girls (14, 16 and 17 years of age). The average largest tumor dimension and volume were 142 mm and 1268 cc in the FBS group, and 73 mm and 252 cc in the remaining group, respectively. FBS tumors usually reach large sizes. Although the sign is rare in children, there are no scientific reports of its occurrence in the first life decade. Color flow mapping and cross-sectional imaging play a pertinent role in distinguishing this uncommon pattern from a malignant mass and enable the selection of an appropriate surgical approach.

Standardizing the surgical management of benign ovarian tumors in children and adolescents: A best practice Delphi consensus statement.

AIM: No widely agreed consensus protocols exist for the management of benign ovarian tumors (BOT) in children. This presents a substantial risk for suboptimal management. We aimed to generate multispecialty consensus guidance to standardize surgical management and provide a clear follow-up protocol for children with BOTs. METHODS: Prospective two-round confidential e-Delphi consensus survey distributed among multispecialty expert panel; concluded by two semistructured videoconferences. MAIN RESULTS: Consensus was generated on these core outcome sets: preoperative/intraoperative management; follow-up; adolescent gynecology referral. (1) Children with BOTs should receive the same management as other patients with potentially neoplastic lesions: Preoperative discussion at a pediatric oncology multidisciplinary meeting to risk stratify tumors, and management by health professionals with expertise in ovarian-sparing surgery and laparoscopy. (2) Ovarian-sparing surgery for BOTs should be performed wherever possible to maximize fertility preservation. (3) Ovarian masses detected during emergency laparoscopy/laparotomy should be left in situ wherever feasible and investigated appropriately (imaging/tumor markers) before resection. (4) Follow-up should be undertaken for all patients after BOT resection. Patients should be offered referral to adolescent gynecology to discuss fertility implications. CONCLUSION: This best practice Delphi consensus statement emphasizes the importance of managing children with BOTs through a well-defined oncological MDT strategy, in order to optimize risk stratification and allow fertility preservation by ovarian-sparing surgery wherever possible.

Analysing triggers for anti-NMDA-receptor encephalitis including herpes simplex virus encephalitis and ovarian teratoma: results from the Queensland Autoimmune Encephalitis cohort.

BACKGROUND: Anti-N-methyl-D-aspartate-receptor (anti-NMDA-R) encephalitis is a complex autoimmune neuropsychiatric syndrome. Although initially associated with ovarian teratoma, subsequent studies have demonstrated that anti-NMDA-R encephalitis may occur without an identifiable cause or be triggered by viral infection of the central nervous system such as herpes simplex virus encephalitis (HSVE). AIM: To present details from a Queensland cohort analysing triggering events in patients with anti-NMDA-R encephalitis in an Australian context. METHODOLOGY: The authors identified patients with anti-NMDA-R encephalitis diagnosed and managed through public hospitals in Queensland, Australia, between 2010 and the end of 2019. Data collected included demographics, clinical presentation, investigation results, management and outcome measurements. RESULTS: Thirty-one cases of anti-NMDA-R encephalitis were included in the study. Three cases of anti-NMDA-R encephalitis were triggered by prior HSVE, five cases were associated with ovarian teratoma and 23 cases had no identifiable trigger. There were an additional three cases in which anti-NMDA receptor antibodies were present in the context of other disease states but where the patient did not develop anti-NMDA-R encephalitis. Cases triggered by HSVE or associated with ovarian teratoma experienced a more severe disease course compared to cases with no identifiable trigger. All groups responded to immunosuppressive or immunomodulatory therapy. Analysis of clinical characteristics revealed a complex heterogeneous syndrome with some variability between groups. CONCLUSION: In this cohort, the number of cases of anti-NMDA-R encephalitis triggered by HSVE is comparable to those triggered by ovarian teratoma. However, the majority of cases of anti-NMDA-R encephalitis had no identifiable trigger or associated disease process.

Prostatic tissue: an unexpected finding in a mature ovarian teratoma : Case report and systematic literature review.

PURPOSE: Prostatic tissue in an ovarian teratoma is an unusual finding, whose initiation in a 46, XX karyotype tissue is yet to be clarified. We present a case from our files and review the literature for this intriguing finding. METHODS: Unstained histology sections of the ovarian teratoma containing prostatic tissue were evaluated using immunohistochemistry for PSA and androgen receptor. RESULTS: Both PSA and androgen receptor immunostainings were positive in the prostatic tissue. From the literature review, it appears that most of the patients (74%) with similar findings were either pregnant or experiencing a miscarriage, menopausal or infertile at presentation, showing that an imbalanced hormone status is frequently associated with the presence of male structures in ovarian teratomas.

Imaging appearance of ovarian mature teratoma with gliomatosis peritonei.

Gliomatosis peritonei (GP), almost exclusively linked to mature or immature ovarian teratoma, is a very rare disease. To the best of our knowledge, reports on the complete clinical course and imaging features of ovarian mature teratoma with GP are extremely rare. We present a case of ovarian mature teratoma with GP in a 9-year-old girl admitted to the emergency department for a 2-month history of a large abdominal mass found accidentally. Carcinoembryonic antigen and cancer antigen 125 levels were elevated. CT scans suggested a large mass with mild enhancement, and an immature teratoma derived from the left ovary with ascites was diagnosed by ultrasound. Subsequently, left ovarian tumor resection and omentectomy were performed, and a solid cystic mass accompanied by massive ascites and numerous white to grayish nodules was identified on the left ovary. The pathology results revealed a mature teratoma with GP. The patient had good postoperative recovery, and her serum tumor marker levels decreased to normal at the 3-month follow-up.

Single nucleotide polymorphism array and cytogenetic analyses of ovarian teratomas in children.

Teratomas are the most common tumors in the ovary during childhood. Previous studies suggested that they may be derived from germ cells at any developmental stage from premeiotic oogonia through meiotic oocytes to post-meiotic ova. The majority of mature teratomas reveal normal karyotypes and immature teratomas show higher frequency of chromosomal abnormalities. We analyzed fresh tissue samples from 25 primary ovarian teratomas and three extraovarian deposits using whole genome single nucleotide polymorphism (SNP) array and karyotype. SNP array detected five patterns of copy neutral loss of heterozygosity (CN-LOH): failure of meiosis I (type I) in 12 tumors, failure of meiosis II (type II) in six tumors, endoreduplication of a haploid ovum (type III) in two tumors, premeiotic error (type IV) in four tumors, and both meiotic I and meiotic II errors in one tumor (type V). Three tumors with type I error had a single chromosome showing meiotic II error, and two tumors with type II error had a single chromosome showing premature sister-chromatid separation in meiosis I. Lack of recombination in multiple chromosomes in meiosis I were common, chromosomes 17, 7, 8, 21, and 22 were most commonly involved. Abnormal karyotypes were observed in four teratomas including +3, del(3q), +7, +8, +12, and i(18q). The extraovarian deposits revealed the same CN-LOH pattern as the primary teratoma. In summary, SNP array reveals the origin of ovarian teratoma and we propose a new mechanism that consecutive meiotic I and II errors occur frequently in ovarian teratomas.

[Ovarian teratoma in children. Clinical case and review of the literature]. / Tératome ovarien chez l'enfant. Revue de la littérature à propos d'un cas clinique.

Summmary : Teratomas are the most common histologic type of germ cell tumors in pediatrics. There are two types of teratomas, mature, benign and immature, malignant. Initial diagnosis is essential for optimal management. This work, based on a clinical case, aims to review the clinical, radiological, biological and histological characteristics allowing them to be differentiated.

Les tératomes sont le type histologique le plus fréquent des tumeurs germinales en pédiatrie. Il existe deux types de tératomes, matures, bénins et immatures, malins. Le diagnostic initial est primordial pour une prise en charge optimale. Ce travail, basé sur un cas clinique, a pour but de reprendre les caractéristiques cliniques, radiologiques, biologiques et histologiques permettant de les différencier.

Successful surgical management of massive ovarian teratoma in a rhesus macaque (Macaca mulatta).

A 5 years-old Rhesus macaque was presented with abdominal enlargement. The clinical, radiographic and ultrasonographic findings suggested that a massive mass occupying the whole of the abdomen. The mass was surgically removed, and histopathology confirmed ovarian teratoma. The macaque recovered uneventfully; however, the management to avoid self-mutilation of skin sutures was challenging.

Successful treatment with immunoadsorption therapy in four patients with severe and refractory anti-N-methyl-D-aspartate receptor encephalitis.

There is still no optimal treatment for patients with severe anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis refractory to first-line therapy (including intravenous methylprednisolone [IVMP] and intravenous immunoglobulin [IVIG]). A small study has shown that immunoadsorption (IA) is effective in treating anti-NMDAR encephalitis. However, the effectiveness and safety of IA in the treatment of patients with refractory and severe anti-NMDAR encephalitis is not fully known. Four patients with severe anti-NMDAR encephalitis are reported, which were refractory to the first-line immunotherapy including IVMP and IVIG. Immunoadsorption is performed during the fulminant stage of disease, and the effectiveness and safety of IA are assessed. The modified Rankin Scale (mRS) is used to assess neurological conditions before and after IA. Four patients with the most severe form of anti-NMDAR encephalitis (two with teratoma and two with unknown origin) did not respond to one or more rounds of IVMP plus IVIG. They all required intensive care unit (ICU) support including long-term mechanical ventilation, and thus developed ICU-related complications. Gradual and steady improvement was observed after IA treatment. Except for mild hypotension in patient 1, no other adverse events were observed during IA. Two patients had good early overall recovery on discharge. The other two patients had a good outcome with mRS of 2 at the 12-month follow-up. This small case series suggests that IA may be an effective treatment option to accelerate the recovery of patients with severe and refractory anti-NMDAR encephalitis.

Surgical management of ovarian teratomas in childhood: a multicentric study on 110 cases and a literature review.

AIM OF THE STUDY: To compare a multicentric surgical experience on ovarian teratomas in childhood with the current management trends. DESIGN: A retrospective multicentric pediatric ovarian teratomas surgically treated between January 2000 and August 2020 at four Italian institutions. PubMed database was used to search for Reviews and Systematic Reviews published between January 2010 and August 2020: 15 manuscripts reported 3633 ovarian neoplasms in pediatric age, 1219 (33,5%) of which were ovarian teratomas. RESULTS: A hundred-ten patients with a mean age at diagnosis of 11.8 years were enrolled. Mature cystic teratomas accounted for the 90% of the masses. At surgery, 78 were oophorectomies and 32 were ovary sparing surgeries. Laparoscopy occurred in 16.3% of the surgeries.As regarding the current management trends, the mean age at diagnosis was 11.9 years and 80.5% of the cases were represented by mature teratomas. Of 430 procedures, 331 were oophorectomies while 99 were ovary sparing surgeries and laparoscopy was performed in 23.8% of cases. CONCLUSIONS: Ovary-sparing surgery with laparoscopic approach is increasingly offered as standard treatment for benign masses that fit the criteria for mature teratomas, in the attempt to achieve the best compromise between the preservation of fertility and the prevention of recurrences. Awareness should be raised among pediatric surgeons to reduce unnecessary radical surgery.

Research progress in teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis: The gynecological perspective.

AIM: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is one of the autoimmune encephalitis, which often occurs in children and young adults, especially in young women. In addition to viral infection, teratoma is an important causative factor. Anti-NMDAR encephalitis is well known to neurologist. However, this is less well known to gynecologists, who may have a decisive role in etiological management. Therefore, from the perspective of gynecologists, we provide an overview of the relationship between the encephalitis and ovarian teratoma, the clinical features and treatment of this disease, and prognosis of pregnant women with this encephalitis. METHODS: We searched the PubMed database using the search terms in various combinations "teratoma," "dermoid cyst," "ovary," "ovarian," "anti-NMDAR encephalitis," and "N-methyl-D-aspartate receptor." RESULTS: According to the current literature, the mechanism of anti-NMDAR encephalitis is probably due to the ectopic expression of the NMDAR in the teratomas tissue. The disease has a high mortality rate if not treated promptly and effectively. An important way to improve patients' outcome is to remove the ovarian tumor in time. Pregnant women are also at risk of developing anti-NMDAR encephalitis during pregnancy. The fetal outcome is usually better in patients with mid- to late-pregnancy onset than in early pregnancy, and patients are often able to maintain their pregnancies into late pregnancy. CONCLUSION: Young women with sudden onset of abnormal psychiatric behavior should be actively screened for ovarian tumors and, if confirmed to be teratoma-associated anti-NMDAR encephalitis, should undergo gynecologic surgery as early as possible, which can help improve their prognosis.

Ovarian teratoma-associated anti-NMDAR encephalitis: a single-institute series of six patients from China.

PURPOSE: Ovarian teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis is a rare disease with uncertain etiology and pathogenesis. The disorder is severe and rare with a great impact on young adults. This study aimed to improve the awareness of the disease from experience in our single center. METHODS: Between July 2012 and December 2019, six patients with ovarian teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis were enrolled in Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University. All patients' data like manifestations, laboratory and radiological data, treatment, and follow-up were reviewed. RESULTS: Typical psychotic symptoms, memory, and consciousness disorders accompanied by seizures were observed in all patients from this study. All six patients showed positive signals in serum and cerebrospinal fluid samples for N-methyl-D-aspartate receptor and received immunotherapy. Three patients underwent unilateral oophorocystectomy and the other three underwent unilateral oophorectomy through minimally invasive surgeries, including laparoscopic and single-port laparoscopic surgeries. The median follow-up time 24.5 months (range from 6 to 93 months). No death occurred. Two patients had recurrent psychotic symptoms while the left four patients had no mental symptoms or tumor recurrence during postoperative follow-up. CONCLUSIONS: For patients with clinical manifestations of unexplained acute psychiatric symptoms accompanied by seizures, memory, and consciousness disorders, the possibility of anti-N-methyl-D-aspartate receptor encephalitis should be considered. To confirm the diagnosis, examinations of anti-N-methyl-D-aspartate receptor antibodies need to be completed as early as possible. Immunotherapy and tumor location should be given in time once the diagnosis is defined. We recommended removing the tumor as soon as possible without concerning whether the patient is in the acute phase or not. The surgical procedure should be decided based on pathology, age, fertility desire, and patients' requirements and it should be ensured that tumors are completely removed during operation. Postoperative follow-up is particularly important.

Distinctive pattern of left-right asymmetry of ovarian benign teratomas in Chinese population: a 12-year-long cross-sectional study.

PURPOSE: Given the lack of research on the left-right asymmetry of ovarian teratoma among Chinese patients, this study aimed to determine the lateral distribution and related clinical characteristics of Chinese ovarian teratoma patients treated at a single center. METHODS: We conducted a cross-sectional study of surgical patients pathologically diagnosed with ovarian teratomas in the gynecology inpatient department of the International Peace Maternity and Child Health Hospital in Shanghai between July 2006 and July 2018. RESULTS: Of the 4417 patients with ovarian teratoma, 3835 were finally analyzed. There were 2030 (53.24%) cases of right-sided benign ovarian teratoma versus 1783 (46.76%) cases of left-sided benign teratoma (P < 0.001). The recurrence rate of benign ovarian teratoma was 4.2%; recurrence occurred more often on the left side (left vs. right = 55 vs. 45%, P = 0.033). Compared with the right-sided ovarian teratoma patients, left-sided ones had significantly high recurrence risk (OR 1.430; 95% CI 1.03-1.99). The rate of ovarian torsion in patients with ovarian mature cystic teratomas (MCTs) during intrauterine pregnancy was 3.17 versus 1.72% in non-pregnant MCT patients (P = 0.049). For those MCT patients with intrauterine pregnancy, ovarian torsion occurs more often on the right side (left vs. right = 16.67 vs. 83.33%, P = 0.028). CONCLUSION: This study confirms a distinctive right-side dominance of benign ovarian teratomas. Compared with the right side, recurrent ovarian teratomas occur more often on the left side, requiring close follow-up. Intrauterine pregnancy may increase the risk of ovarian torsion, particularly on the right side, in MCT patients.

The Association of Ovarian Teratoma and Anti-N-Methyl-D-Aspartate Receptor Encephalitis: An Updated Integrative Review.

Ovarian teratomas are by far the most common ovarian germ cell tumor. Most teratomas are benign unless a somatic transformation occurs. The designation of teratoma refers to a neoplasm that differentiates toward somatic-type cell populations. Recent research shows a striking association between ovarian teratomas and anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis, a rare and understudied paraneoplastic neurological syndrome (PNS). Among teratomas, mature teratomas are thought to have a greater relevance with those neurological impairments. PNS is described as a neurologic deficit triggered by an underlying remote tumor, whereas anti-NMDAR encephalitis is characterized by a complex neuropsychiatric syndrome and the presence of autoantibodies in cerebral spinal fluid against the GluN1 subunit of the NMDAR. This review aims to summarize recent reports on the association between anti-NMDAR encephalitis and ovarian teratoma. In particular, the molecular pathway of pathogenesis and the updated mechanism and disease models would be discussed. We hope to provide an in-depth review of this issue and, therefore, to better understand its epidemiology, diagnostic approach, and treatment strategies.

Autoimmune anti-N-methyl-D-aspartate receptor encephalitis - paraneoplastic syndrome of ovarian teratoma.

OBJECTIVE: Case presentation and subsequent dia-gnostic and therapeutic procedure of autoimmune encephalitis caused by the presence of ovarian teratoma. CASE REPORT: We describe the case of a young woman with symptoms of an acute psychotic attack unresponsive to antipsychotic treatment. Anti-N-methyl-D-aspartate receptor encephalitis was dia-gnosed within the interdisciplinary cooperation at the University Hospital in Olomouc. CONCLUSION: This type of rare and potentially fatal paraneoplastic limbic encephalitis occurs predominantly in young women. Due to the high variability of neuropsychiatric symptoms, the dia-gnosis of the disease is very difficult, and therefore patients are often primarily incorrectly treated for other neurological or psychiatric diseases. The most prognostically important part is early dia-gnosis and adequate therapy.

Single-cell transcriptional profiling identifies a cluster of potential metastasis-associated UBE2C+ cells in immature ovarian teratoma.

To dissect the disease heterogeneity and identify the underlying cellular and molecular events related to metastasis of immature ovarian teratoma in children, single-cell RNA sequencing was performed for a 2-year-old patient with liver metastases from immature ovarian teratoma. A total of 5976 cells were obtained for further analysis, with a median unique molecular identifier count of 6011 per cell and a median number of 1741 genes detected per cell. Fourteen clusters were recognized, with the main lineages comprising epithelial cells, macrophages, fibroblasts, glial cells, and dendritic cells. Ten subclusters of epithelial cells were further defined, originating from the urinary tract, esophagus, bronchus, lung, skin, and gastrointestinal tract. An undefined UBE2C + population in an active state of proliferation was also identified and its biological processes were related to meiosis and maturation of oocytes. Pseudotime analysis revealed different distributions of epithelial cells in the development trajectory. In conclusion, a cluster of UBE2C + epithelial cells in an active state of proliferation was identified in an immature ovarian teratoma in a child, and may contribute to metastasis by regulating epithelial-mesenchymal transition. These findings help toward understanding the origin of the malignant behaviors, offer a potential biomarker for early determination of the tumor nature, and provide new ideas for the therapy of immature ovarian teratoma in children.

HLA-A and HLA-DRB1 may play a unique role in ovarian teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis.

BACKGROUND: Ovarian teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis (NMDAR-E) is a severe autoimmune neurological disorder, and the influence of teratoma-induced autoantibodies on the pathogenesis remains unclear. METHODS: Ovarian teratoma tissues were collected from teratoma patients with and without NMDAR-E. Proteins were extracted and then analyzed using iTRAQ-coupled LC-MS/MS, which was followed by bioinformatics analysis. Candidate proteins were verified by Western blotting and immunohistochemistry. RESULTS: In total, 36 differentially expressed proteins (DEPs) were identified between the control group and NMDAR-E group, and the bioinformatics analysis revealed that the DEPs were mainly involved in immune-related pathways, especially HLA-A and HLA-DRB1. The western blotting results for HLA-A and HLA-DRB1 were consistent with the results of the iTRAQ analysis. Additionally, the immunohistochemical data revealed that the aggregation of HLA-A (+) and HLA-DRB1 (+) cells was more apparent in the teratoma tissues of NMDAR-E patients compared with that in the tissues of controls. CONCLUSION: Our investigation indicated that HLA-A and HLA-DRB1 might be involved in mediating ovarian teratoma-associated NMDAR-E. These findings provide new insights into the pathophysiological mechanisms and provide information for the functional exploration of proteins in the future.