Anti-metabolic glutamate receptor 5 encephalitis with gangliocytoma: a case and review of the literature.

BACKGROUND: There are very limited reports on anti-metabolic glutamate receptor5 (mGluR5) encephalitis, especially lacking of pediatric research. The disease was mostly accompanied by tumors, mainly Hodgkin's lymphoma. No reports of other tumors, such as gangliocytoma have been reported to associate with anti-mGluR5 encephalitis so far. CASE PRESENTATION AND LITERATURE REVIEWS: We reported a case of a 12-year-old boy with anti-mGluR5 encephalitis complicated with gangliocytoma. The patient suffered from mental disorders including auditory hallucination, and sleep disorders. His cranial magnetic resonance imaging (MRI) showed an abnormality in the right insular lobe. Autoimmune encephalitis antibodies testing was positive for mGluR5 IgG antibody both in cerebrospinal fluid and serum (1:3.2, 1:100 respectively). Abdominal CT indicated a mass in left retroperitoneal confirmed with gangliocytoma via pathology. The patient underwent resection of gangliocytoma. After first-line immunotherapy (glucocorticoid, gamma globulin), his condition was improved. Furthermore, we provide a summary of 6 pediatric cases of Anti-mGluR5 encephalitis. Most of them complicated with Hodgkin's lymphoma, except the case currently reported comorbid with gangliocytoma. The curative effect is satisfactory. CONCLUSIONS: We report the first patient with anti-mGlur5 encephalitis complicated with gangliocytoma. It suggests that in addition to paying attention to the common lymphoma associated with anti-mGlur5 encephalitis, we should also screen the possibility of other tumors for early detection of the cause, active treatment and prevention of recurrence.

Composite paraganglioma-ganglioneuroma with atypical catecholamine profile and phenylethanolamine N-methyltransferase expression: a case report and literature review.

Pheochromocytomas and paragangliomas (PPGLs) are rare tumors that secrete catecholamines and arise from the adrenal medulla or extra-adrenal sympathetic ganglia. These tumors secrete adrenaline and noradrenaline, but paragangliomas usually produce only noradrenaline because of the lack of phenylethanolamine N-methyltransferase (PNMT) expression. Composite paragangliomas, which are complex tumors consisting of multiple types of neuroblastic cells, are extremely rare. We present the case of a 46-year-old woman with an atypical catecholamine profile who was preoperatively diagnosed with pheochromocytoma. However, postoperative pathology revealed that the patient had an extra-adrenal paraganglioma accompanied by a ganglioneuroma, which led to the diagnosis of a composite tumor. Interestingly, PNMT is expressed in both paragangliomas and ganglioneuromas. In addition, we reviewed reported composite paragangliomas and compared their clinical features with those of composite pheochromocytomas. We also discuss various aspects of the etiology of composite paragangliomas and the mechanism by which PNMT is expressed in tumors.

Neuropil-like islands are a possible pathogenetic link between glioblastoma and gangliocytoma/ganglioglioma in a case of synchronous bilateral brain tumors.

Neuropil-like islands (NIs) are a histologic hallmark of glioneuronal tumors with neuropil-like islands (GTNIs), but GTNIs are presently not considered a homogeneous entity. The essence of GTNI is likely its glial component, and NIs are now considered aberrant neuronal differentiation or metaplasia. The case we report herein is a 41-year-old woman who was synchronously affected by two brain tumors: one was a glioblastoma (glioblastoma multiforme, GBM), of isocitrate dehydrogenase (IDH)-wild type, with NIs in the left parietal lobe, and the other was histologically a composite gangliocytoma (GC)/anaplastic ganglioglioma (GG) with NIs in the right medial temporal lobe. While both tumors were genetically wild type for IDH, histone H3, and v-raf murine sarcoma viral oncogene homolog B1 (BRAF), the former tumor, but not the latter, was mutated for telomerase reverse transcriptase promoter gene (TERT). A recent systematic study using DNA methylation profiling and next-generation sequencing showed that anaplastic GG separate into other WHO tumor types, including IDH-wild-type GBM. It suggested a diagnostic scheme where an anaplastic GG is likely an IDH-wild-type GBM if it is a BRAF wild type, IDH wild type, and TERT promoter mutant tumor. The likely scenario in this patient is that the GBM results from the progression of GC/anaplastic GG due to the superimposed TERT promoter mutation and the propagation of newly generated GBM cells in the contralateral hemisphere. A systematic analysis using DNA methylation profiling and next-generation sequencing was not available in this study, but the common presence of NIs histologically noted in the two tumors could support this scenario. Although a sufficient volume of molecular and genetic testing is sine qua non for the accurate understanding of brain tumors, the importance of histologic observation cannot be overemphasized.

Esophageal ganglioneuromatosis; a rare cause of intractable esophageal stenosis: a case report.

BACKGROUND: Ganglioneuromatosis is a rare type of benign neurogenic tumor that usually affects the sites of the major sympathetic ganglia in the retroperitoneum and the posterior mediastinum. Affection of the gastrointestinal tract is rare, and involvement of the esophagus is exceptional. To the best of our knowledge, only 4 cases of esophageal ganglioneuromatosis in adults were reported in the literature. No cases have been reported in the pediatric age group. CASE PRESENTATION: An 11-year-old boy presented with dysphagia due to severe esophageal stenosis caused by esophageal ganglioneuromatosis. CONCLUSIONS: Despite its rarity, the present case implies that ganglioneuromatosis should be considered in children with idiopathic esophageal stenosis.

Successful endoscopic approach for peripheral neuroblastic tumors in children.

BACKGROUND: Recently, reports of endoscopic approaches for neuroblastoma, ganglioneuroblastoma, and ganglioneuroma (peripheral neuroblastic tumor; PNTs) have been increasing. This study aimed to clarify the indications for endoscopic surgery for PNTs. METHODS: Pediatric patients who underwent endoscopic surgery for PNTs at our institution were included in this study. Image-defined risk factors (IDRFs) were analyzed using preoperative computed tomography (CT). RESULTS: Twenty-four patients underwent endoscopic surgery for PNTs. The diagnoses included neuroblastoma (n = 11), ganglioneuroma (n = 10), and ganglioneuroblastoma (n = 3). Regarding the tumor site, there were 18 cases of adrenal tumors, five cases of mediastinal tumors, and one case of retroperitoneal tumors. Image-defined risk factors were positive in eight cases (contacted with a renal vessel, n = 6; compression of principal bronchi, n = 2). Complete resection was accomplished in 21 cases (14 of 16 IDRF-negative cases and seven of eight IDRF-positive cases). All patients survived without recurrence during the follow-up period. CONCLUSIONS: The CT findings of contact with renal vessels and compression of principal bronchi do not seem to be indicators of incomplete resection. An endoscopic approach to PNTs in pediatric patients is feasible with a good prognosis if patients are selected strictly.

Cervical Ganglioneuroma Associated With Neurofibromatosis Type 1.

Cervical ganglioneuroma combined with neurofibromatosis type I is very rare. This article reports a case of a 21-year-old male patient with a rare presentation of cervical ganglioneuroma and neurofibromatosis type I. In this patient, the tumors on both sides of the cervical spine were surgically removed with good results. The effects and advantages of surgery when both diseases coexist are discussed, as well as further investigation into possible causal relationships between these two pathologies.

Diffuse intestinal ganglioneuromatosis. A post mortem diagnosed challenging case.

Intestinal ganglioneuromatosis (GN) is a benign disease of the autonomic nervous system characterized by hyperplasia of intramural plexuses of the gastrointestinal tract and enteric nerve fibers. Next, we expose an intestinal ganglioneuromatosis case that was difficult to diagnose despite an exhaustive evaluation, for further understanding of the disease.

[Surgically Resected Cases of Mediastinal Ganglioneuroma Detected in Adults].

A ganglioneuroma is a rare, benign, neurogenic tumor originating from the sympathetic ganglion. Mediastinal ganglioneuroma are mostly detected in children, typically around 10 years of age, and are rarely identified in adults. Herein, we report two surgically resected cases of mediastinal ganglioneuroma in adults. In Case 1, a 53-year-old man, without any symptom, underwent a computed tomography, revealing a 3.2 cm well-defined paravertebral superior mediastinal tumor with long craniocaudal axis. In case 2, a 29-year-old woman presented with newly-developed ptosis and a history of left-sided facial hypohidrosis since the age of 10. Chest computed tomography (CT) revealed a 7.8 cm well-defined paravertebral superior mediastinal tumor with long craniocaudal axis. Both patients were initially suspected to have neurogenic tumors, particularly schwannomas. They underwent mediastinal tumor resections, requiring sympathetic nerve trunk dissection. Pathological examination confirmed the diagnosis of ganglioneuromas in both cases. Mediastinal ganglioneuroma must be differentiated from schwannoma, the most common neurogenic tumor in adults. Unlike schwannoma, ganglioneuroma cannot be enucleated, therefore attention should be focused on complications associated with sympathetic nerve trunk dissection, such as Horner's syndrome, hyperhidrosis, and arrhythmia. Identifying this rare entity and its characteristic imaging aids in preoperative differentiation, strategizing surgical approaches, and predicting complications.

Multiple endocrine neoplasia type 2: A review.

Multiple endocrine neoplasias are rare hereditary syndromes some of them with malignant potential. Multiple endocrine neoplasia type 2 (MEN 2) is an autosomal dominant hereditary cancer syndrome due to germline variants in the REarranged during Transfection (RET) proto-oncogene. There are two distinct clinical entities: MEN 2A and MEN 2B. MEN 2A is associated with medullary thyroid carcinoma (MTC), phaeochromocytoma, primary hyperparathyroidism, cutaneous lichen amyloidosis and Hirschprung's disease and MEN 2B with MTC, phaeochromocytoma, ganglioneuromatosis of the aerodigestive tract, musculoskeletal and ophthalmologic abnormalities. Germline RET variants causing MEN 2 result in gain-of-function; since the discovery of the genetic variants a thorough search for genotype-phenotype associations began in order to understand the high variability both between families and within family members. These studies have successfully led to improved risk classification of prognosis in relation to the genotype, thus improving the management of the patients by thorough genetic counseling. The present review summarizes the recent developments in the knowledge of these hereditary syndromes as well as the impact on clinical management, including genetic counseling, of both individual patients and families. It furthermore points to future directions of research for better clarification of timing of treatments of the various manifestations of the syndromes in order to improve survival and morbidity in these patients.

Retrospective Analysis of Retroperitoneal-Abdominal-Pelvic Ganglioneuromas: An International Study by the Transatlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG).

OBJECTIVE: The Transatlantic Australasian Retroperitoneal Sarcoma Working Group conducted a retrospective study on the disease course and clinical management of ganglioneuromas. BACKGROUND: Ganglioneuromas are rare tumors derived from neural crest cells. Data on these tumors remain limited to case reports and single-institution case series. METHODS: Patients of all ages with pathologically confirmed primary retroperitoneal, intra-abdominal, and pelvic ganglioneuromas between January 1, 2000, and January 1, 2020, were included. We examined demographic, clinicopathologic, and radiologic characteristics, as well as clinical management. RESULTS: Overall, 328 patients from 29 institutions were included. The median age at diagnosis was 37 years with 59.1% of patients being female. Symptomatic presentation comprised 40.9% of cases, and tumors were often located in the extra-adrenal retroperitoneum (67.1%). At baseline, the median maximum tumor diameter was 7.2 cm. One hundred sixteen (35.4%) patients underwent active surveillance, whereas 212 (64.6%) patients underwent resection with 74.5% of operative cases achieving an R0/R1 resection. Serial tumor evaluations showed that malignant transformation to neuroblastoma was rare (0.9%, N=3). Tumors undergoing surveillance had a median follow-up of 1.9 years, with 92.2% of ganglioneuromas stable in size. With a median follow-up of 3.0 years for resected tumors, 84.4% of patients were disease free after resections, whereas recurrences were observed in 4 (1.9%) patients. CONCLUSIONS: Most ganglioneuromas have indolent disease courses and rarely transform to neuroblastoma. Thus, active surveillance may be appropriate for benign and asymptomatic tumors particularly when the risks of surgery outweigh the benefits. For symptomatic or growing tumors, resection may be curative.

RET overactivation leads to concurrent Hirschsprung disease and intestinal ganglioneuromas.

Appropriately balanced RET signaling is of crucial importance during embryonic neural crest cell migration, proliferation and differentiation. RET deficiency, for example, leads to intestinal aganglionosis (Hirschsprung disease), whereas overactive RET can lead to multiple endocrine neoplasia (MEN) syndromes. Some RET mutations are associated with both intestinal aganglionosis and MEN-associated tumors. This seemingly paradoxical occurrence has led to speculation of a 'Janus mutation' in RET that causes overactivation or impairment of RET activity depending on the cellular context. Using an intestinal catenary culture system to test the effects of GDNF-mediated RET activation, we demonstrate the concurrent development of distal colonic aganglionosis and intestinal ganglioneuromas. Interestingly, the tumors induced by GDNF stimulation contain enteric neuronal progenitors capable of reconstituting an enteric nervous system when transplanted into a normal developmental environment. These results suggest that a Janus mutation may not be required to explain co-existing Hirschsprung disease and MEN-associated tumors, but rather that RET overstimulation alone is enough to cause both phenotypes. The results also suggest that reprogramming tumor cells toward non-pathological fates may represent a possible therapeutic avenue for MEN-associated neoplasms.

Image-defined risk factors in localized thoracic neuroblastoma and ganglioneuroma.

BACKGROUND: The pretreatment International Neuroblastoma Risk Group Staging System (INRGSS) discriminates localized tumors L1/L2 depending on the absence/presence of image-defined risk factors (IDRFs) at diagnosis. Referring to this new staging system, we assessed initial imaging of localized thoracic neuroblastoma (NB) and ganglioneuroma (GN) and the extent of initial tumor resection. METHODS: Patients with localized thoracic NB/GN from the German clinical trials NB97 and NB2004 were included. Imaging at diagnosis and operative reports were reviewed retrospectively. IDRFs were assessed centrally and correlated to International Neuroblastoma Staging System (INSS) stage and extent of tumor resection. Additionally, we analyzed data on surgery-related complications. RESULTS: Imaging series of 88 patients were available for central review. In 18 children, no IDRF was present, 28 exhibited one IDRF, 42 two or more IDRFs, resulting in 70 patients with L2 disease. The most frequently observed IDRF was encasement of any vessel (n = 38). Initial surgical resection was aimed for in 45 patients (L1: n = 11; L2: n = 34). Complete and gross total resection rates were higher children with L2 NB (n = 8/25 L1, n = 17/25 L2 vs. n = 2/15 L1, n = 13/15 L2, respectively). The proportion of surgical complications was very similar between INRGSS L1 and L2 (n = 4/11 vs. n = 17/34). All complications were manageable, and no surgery-related deaths were observed. CONCLUSION: In this retrospective cohort, the extent of resection and the rate of surgical complications did not differ substantially between patients classified as L1/L2, indicating that INRGSS L2 does not equate unresectability. It appeared that individual IDRFs differ in value. Larger studies are needed to assess the significance and therapeutic/prognostic impact of such findings.

An Unusual Case of Late Recurrence of MS Neuroblastoma in a Young Adult.

This case describes an unusual presentation of a young adult with a very late recurrence of stage MS neuroblastoma over 20 years after initial diagnosis. Tumor histology at relapse demonstrated ganglioneuromatous foci within her undifferentiated tumor. In combination with evidence of altered catecholamine metabolism, it proposes a case for dedifferentiation of unresected ganglioneuromatous lesions as the etiology of her recurrence of the disease. An additional, compelling component of the case is the overall positive treatment response of the patient with relapsed neuroblastoma despite the poor prognostic factors of late relapse and adult age.

Diverse imaging findings of Lhermitte-Duclos disease.

AIM: To evaluate the diverse clinical and imaging features of Lhermitte-Duclos disease (LDD) and its subgroup comparison. MATERIALS AND METHODS: Clinical data from 21 patients with LDD were collected, including eight patients with LDD without other tumours and 13 LDD with other tumours. Redefined diagnostic criteria are used to evaluate Cowden Syndrome. Imaging indicators were analysed retrospectively to extract typical and atypical features. Imaging findings and preoperative diagnostic accuracy were compared between the subgroups. RESULTS: None of these patients met the redefined diagnostic criteria. The typical "tiger stripe sign" was seen in most LDD lesions (13/29, 61.9%), with lower density (29.66 ± 2.51 versus 37.81 ± 2.76 HU, p<0.001) and higher apparent diffusion coefficient (ADC) value (1.04 ± 0.05 × 10-3 versus 0.74 ± 0.03 × 10-3 mm2/s, p<0.001) than that of the normal cerebellum. Atypically, some lesions showed abnormal vessels (8/21, 38.1%), intratumoural calcification (3/21, 14.29%), intratumoural haemorrhage (4/21, 19.05%), peritumoural oedema (6/21, 28.57%), and heterogeneous enhancement (5/21, 23.81%). The typical "tiger stripe sign" was more common in LDD with other tumours (84.62% versus 25%, p=0.018). Although LDD without other tumours was more common with abnormal vessels (75% versus 15.38%, p=0.018), intratumoural calcification (37.5% versus 0, p=0.042), intratumoural haemorrhage (50% versus 0, p=0.012), peritumoural oedema (62.5% versus 7.69%, p=0.014) and heterogeneous enhancement (50% versus 7.69%, p=0.047). Preoperative diagnostic accuracy was higher in LDD with other tumours than LDD without other tumours (76.92% versus 25%, p=0.032). CONCLUSION: The "tiger stripe sign" of LDD is characteristic, but not unique. With or without other tumours, it may be associated with the imaging diversity. Combining typical and atypical signs can improve the imaging assessment of LDD.

Preoperative differentiation of mediastinum and retroperitoneum ganglioneuroma from schwannoma with clinical data and enhanced CT: developing a multivariable prediction model.

AIM: To develop a multivariable prediction model for preoperative differentiation of ganglioneuroma (GN) from schwannoma in mediastinum and retroperitoneum based on clinical data and enhanced computed tomography (CT). MATERIALS AND METHODS: This was a retrospective diagnostic study. Patients diagnosed with mediastinum or retroperitoneal GN or schwannoma at Zhongshan Hospital between July 2006 and March 2022 were divided into a training cohort and a validation cohort at a ratio of 7:3. Clinical information and CT features were collected. Histopathology was the reference standard for diagnosis. The model was developed using binary logistic regression. The predictive performance of the model was assessed using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). RESULTS: A total of 105 patients (47 men and 58 women; mean age of 41 ± 15 years) were enrolled. There were significant differences in symptoms (p=0.006), location (p=0.008), ratio of the craniocaudal diameter (CC) to the major axis on axial images (CC/M; p=0.025), ratio of the CC to the diameter on axial images (CC/D; p<0.001), density homogeneity (p=0.001), enhancement homogeneity (p<0.001), enhancement degree (p<0.001), venous phase CT attenuation value (V; p=0.011), and blood vessels changes (p=0.045) between GN and schwannoma. The area under the ROC curve (AUC) and accuracy in the validation cohort were 0.841 (95% confidence interval [CI] 0.672, 1.000) and 0.839 (95% CI: 0.674, 0.929), respectively. Calibration curves and DCA showed that the model was beneficial for patients. CONCLUSION: The multivariable prediction model exhibited good predictive performance and may facilitate preoperative planning.

Identification and validation of radiomic features from computed tomography for preoperative classification of neuroblastic tumors in children.

BACKGROUND: To identify radiomic features that can predict the pathological type of neuroblastic tumor in children. METHODS: Data on neuroblastic tumors in 104 children were retrospectively analyzed. There were 14 cases of ganglioneuroma, 24 cases of ganglioneuroblastoma, and 65 cases of neuroblastoma. Stratified sampling was used to randomly allocate the cases into the training and validation sets in a ratio of 3:1. The maximum relevance-minimum redundancy algorithm was used to identify the top 10 of two clinical features and 851 radiomic features in portal venous-phase contrast-enhanced computed tomography images. Least absolute shrinkage and selection operator regression was used to classify tumors in two binary steps: first as ganglioneuroma compared to the other two types, then as ganglioneuroblastoma compared to neuroblastoma. RESULTS: Based on 10 clinical-radiomic features, the classifier identified ganglioneuroma compared to the other two tumor types in the validation dataset with sensitivity of 100.0%, specificity of 81.8%, and an area under the receiver operating characteristic curve (AUC) of 0.875. The classifier identified ganglioneuroblastoma versus neuroblastoma with a sensitivity of 83.3%, a specificity of 87.5%, and an AUC of 0.854. The overall accuracy of the classifier across all three types of tumors was 80.8%. CONCLUSION: Radiomic features can help predict the pathological type of neuroblastic tumors in children.

A Metastatic Neuroblastic Tumor in a 28-Month-old Boy: Unusual Spontaneous Regression From Neuroblastoma to Ganglioneuroma?

Neuroblastoma with bone metastasis is well known to have an extremely poor prognosis. We experienced the case of a patient with adrenal ganglioneuroblastoma (GNB) with metastases of subcutaneous nodules, a lymph node, and multiple bones. A pathologic examination of tumors from different sites revealed both GNB and ganglioneuroma. A genetic comparison between these tumors identified the same molecular signatures, suggesting the possibility of spontaneous differentiation in the remaining GNB. The patient has been healthy without aggressive chemotherapy, and the patient's pathologic urinary catecholamines normalized. Even if unusual, we have to recognize probable spontaneous differentiation from neuroblastoma to GNB and then to ganglioneuroma, even in sites of bone metastasis.

Ganglion cell maturation in peripheral neuroblastic tumours of children.

Peripheral neuroblastic tumours of neural crest origin are the most frequent solid neoplasms outside the CNS in children. Neuroblastoma/ganglioneuroblastoma/ganglioneuroma have a natural evolution of histological differentiation over time. Together with mitosis-karyorrhexis index and patient age (International Neuroblastoma Pathology Classification criteria), ganglion cell maturation determines grading and prognosis. Maturation presently is usually assessed only histologically. Immunocytochemical tissue markers defining neuroblast maturation in fetal CNS were here applied to peripheral neuroblastic tumours arising in the adrenal medulla or sympathetic chain. Paraffin sections of resected tumours of 4 toddlers were examined using antibodies demonstrating neuronal identity and maturation: MAP2; synaptophysin; chromogranin-A; NeuN; keratan sulfate (KS); glutamate receptor antibody (GluR2). Synaptophysin, normally a late marker of neuroblast differentiation, was the earliest expressed in neuroblastoma. Others include: Ki67; S-100ß protein; vimentin; nestin; α-B-crystallin; neuroblastoma marker PHOX2B. Various degrees of ganglion cell maturation were demonstrated by MAP2, chromogranin, synaptophysin, KS, and GluR2; NeuN was uniformly negative, consistent with sympathetic neurons. KS was sparsely distributed within the tumours in interstitial tissue, within processes of some non-neuronal cells, and adherent to somata and proximal neuritic trunks. Neoplastic ganglion cells with multiple nuclei matured similar to mono-nuclear forms. PHOX2B did not distinguish maturational stages. S-100ß protein and α-B-crystallin labeled Schwann cells, especially Schwannian ganglioneuroma. Immunocytochemical markers of neuroblast maturation in fetal brain also are useful in peripheral neuroblastic tumours, providing greater precision than histology alone. The most practical are MAP2, chromogranin-A, and synaptophysin. Prognosis and choice of treatment including chemotherapy might be influenced.

Mediastinal neuroblastoma, ganglioneuroblastoma, and ganglioneuroma: Pathology review and diagnostic approach.

Neuroblastic tumors are a group of tumors of the sympathetic ganglia and adrenal medulla that derive from primordial neural crest cells. These tumors include neuroblastoma, intermixed ganglioneuroblastoma, nodular ganglioneuroblastoma, and ganglioneuroma. Neuroblastomas are the most common extracranial solid tumor arising in childhood and may occur in different anatomic sites. Neuroblastic tumors are common mesenchymal tumors of the mediastinum. Herein, we describe advances in our understanding of neuroblastic tumor biology. Pathologists should be aware of diagnostic challenges associated with these tumors to ensure correct histologic diagnosis and appropriate clinical management. We describe updated mediastinal neuroblastic tumor pathology, focusing on morphological, immunohistochemical, and molecular features and differential diagnoses.

Mixed gangliocytoma-pituitary adenoma in MEN1 syndrome: A case report and literature review.

Pituitary adenoma is one of the three most common neoplasms described in multiple endocrine neoplasia type 1 (MEN1), and patients with pituitary adenoma occupies 30-50% of those with MEN1-related tumor. Mixed gangliocytoma-pituitary adenoma (MGPA) is a rare clinical entity in which gangliomatous cells are intermixed with adenomatous cells. This tumor has been estimated to account for 0.52-1.26% of all pituitary tumors. We report a rare case of MGPA in a patient with MEN1. A retrospective chart review was conducted on a patient with MEN1 diagnosed with MGPA in 2019 at a single tertiary academic medical center. A review of the literature was performed on MGPA and pituitary adenoma in MEN1. MGPA is rare, with only 174 cases previously reported in the literature and only three prior case reported in a patient with MEN1. There are multiple hypotheses regarding their pathogenesis, and it is unclear whether the MEN1 gene (menin) plays a role in the pathogenesis of MGPA. This tumor in MEN1 is a rare clinical entity of unknown etiology. Further studies are required with difficulty due to its low incidence.