Intracranial Fetus In Fetu-a Pediatric Rarity

BACKGROUND

Intracranial fetus in fetu is an extremely rare entity in which a discrete vertebrate fetiform mass is found inside a diamniotic, monochorionic twin. It is a benign mass and can manifest with symptoms owing to mass effect. To establish the diagnosis, a vertebra must be present within the mass.

CASE DESCRIPTION

A 5-year-old child presented at a multispecialty hospital with gradual weakness of both lower limbs. Magnetic resonance imaging of the brain revealed a midline intraventricular mass with lobulated margins having both cystic and fatty components with areas of blooming within. A provisional diagnosis of teratoma/primitive neuroectodermal tumor was made. The patient subsequently presented to our hospital with drowsiness and vomiting for 1 day. Noncontrast computed tomography revealed a mass of heterogeneous density occupying the third ventricle. The mass contained a few well-formed long bones representative of the appendicular skeleton and a vertebra-like bone representative of the axial skeleton, fulfilling the Willis criteria. A biopsy sample was taken from the mass; no malignant cells were seen on histopathologic examination. Based on noncontrast computed tomography findings of well-formed long bones and a vertebra and no significant increase in the size of the mass over 2 years, an intracranial fetus in fetu was diagnosed.

CONCLUSIONS

Whenever bony structures are identified in an intracranial mass in a pediatric patient, we should always look for bones of the axial skeleton, as this finding will point toward a diagnosis of intracranial fetus in fetu and will help in differentiating it from teratoma, which can have malignant transformation.

Ethanol extract of Magnoliae cortex (EEMC) limits teratoma formation of pluripotent stem cells by selective elimination of undifferentiated cells through the p53-dependent mitochondrial apoptotic pathway

BACKGROUND

Induced pluripotent stem cells (iPSCs) are regarded as the best potential cell source for cell-based regenerative medicine. To develop a safe and efficient iPSC-based cell therapy, it is very important to avoid possible teratoma formation, which can arise from undifferentiated iPSCs (USCs) remaining among differentiated cell products. Dried bark of Magnolia officinalis (Magnolia cortex, MC) has long been used in traditional medicine to treat gastrointestinal ailments and allergic diseases, and has shown have various pharmacological activities, including anti-bacterial, anti-inflammatory, and anti-cancer effects. However, its effects on iPSCs have not yet been examined.

PURPOSE

In this study, we investigated the selective cytotoxic effects of ethanol extract of MC (EEMC) on undifferentiated iPSCs and elucidated the underlying apoptotic mechanisms in detail. We also investigated the inhibitory effects of EEMC on teratoma formation via in ovo experiments.

RESULTS

We found that EEMC greatly reduced cell growth and induced apoptotic cell death in USCs, but not in differentiated or normal cells. EEMC caused G2/M cell cycle arrest, mitochondrial damage, and caspase activation of USCs, accompanied by p53 accumulation. In p53KO human iPSCs, EEMC had no cytotoxicity, reinforcing that EEMC-mediated apoptosis of USCs is p53-dependent. EEMC did not cause DNA damage in iPSC-derived differentiated cells. In ovo teratoma formation assay revealed that EEMC treatment before injection efficiently eliminated USCs and prevented teratoma formation.

CONCLUSIONS

These results collectively indicate that EEMC has potent anti-teratoma activity, and therefore can be used for the development of safe iPSC-based therapy.

[Testicular tumors in prepubertal boys-organ preservation possible more often than expected]

In prepubertal boys, testicular tumors are rare with an incidence between 2 and 5/million. In contrast to testicular tumors in adolescents and adults, more than 2/3 of these tumors are benign. Unfortunately, in Germany in most cases, only malignant tumors (usually yolk sac tumors) are reported to the study center (MAKEI IV and now V). Therefore, the incidence in Germany is unknown. Since the introduction of polychemotherapy in the 1970s, the prognosis of malignant testicular tumors has improved enormously and has become a curable disease, even in the case of recurrence. Today the orchiectomy, which was usually carried out in the past, appears to be no longer justified in most prepubertal boys due to the high incidence of benign tumors. It has been shown in various studies that organ-sparing surgery in germ cell tumors (epidermoid cysts, teratoma); gonadal stoma tumors (Sertoli, Leydig and granulosa cell tumors) and cystic lesions (intratesticular cysts and tubular ectasia of the rete testis) is reliable and safe. In cases with preoperative significantly increased AFP (caution: norm values not valid in the first year of life) and a clear testicular tumor in the ultrasound (yolk sac tumor) or if no testicular parenchyma is sonographically detectable, orchiectomy can still be carried out. Today orchiectomies in prepubertal boys should be an exception and the reasons for an orchiectomy must be well documented.

Occipital teratoma in a neonate with CHARGE syndrome: a case report

INTRODUCTION

Teratomas of the head and neck region are rare lesions, representing just 5% of all congenital teratomas. Usually found in the pineal region orneurohypophysis, teratomas are uncommonly located in the posterior occiput.

CASE PRESENTATION

Herein, we present a case of a female neonate born at 37-week gestation with hydrocephalus, an occipital scalp lesion, and several craniofacial abnormalities consistent with a diagnosis of coloboma, heart defect, atresia choanae, retarded growth, genital abnormality, and ear abnormality (CHARGE) syndrome. The occipital scalp lesion was initially thought to be an encephalocele. On day of life 3, the neonate was taken to the operating room for placement of a ventriculoperitoneal shunt and repair of the occipital lesion. Intra-operatively, the lesion resembled a dural-based meningocele; however, during histologic evaluation, it was found to contain tissue derived from all three germ layers and thus, it was determined to be more consistent with a teratoma.

CONCLUSION

We hypothesize that a germline mutation in CHD7 or other similar regulatory gene causative of CHARGE syndrome and craniofacial developmental abnormalities may have contributed to the unusual location of the teratoma in this case.

Mature cystic ovarian teratoma without intracystic fat: Case report with the "fat within the wall" sign

Mature cystic teratoma is the most common ovarian neoplasm among young females. Diagnosed through radiological imaging as it exhibits typical radiological features; typically, fat. However, complete cystic teratoma without visible fat is a very rare and challenging diagnosis. It is difficult to distinguish it from malignant neoplasm, due to the presence of enhancing components, for example, Rokitansky nodule and the presence of diffusion restriction from keratinized products. We present a case of an incidental mature cystic teratoma without visible intracystic fat, where the correct diagnosis based on imaging was failed. Mature cystic teratoma was then confirmed upon histologic examination.

Mature Cystic Teratoma of Spinal Cord in a 16-Year-Old Male: A Case Report

Teratoma is a type of multipotential cell tumor, which includes a mixture of two or three germinal layers of ectodermis, endodermis, and mesodermis. Although neonatal sacrococcygeal teratoma has been frequently reported, its occurrence in older age is not common. In this study, we report a rare case of spinal intradural mature cystic teratoma in a 16-year-old male, emphasizing on considering this unusual condition in differential diagnosis of spinal cord cystic tumors.

Paediatric Thoracic Tumour Resection: Challenge For An Anaesthesiologist

Paediatric thoracic tumours resection is one of the most difficult procedure for any anaesthetist. Paediatric population is different from adults in many aspects, as they have small thoracic volume and more compressible mass effect on their airway and vascular structures. we are reporting a case of a huge paediatric thoracic tumour resection occupying the left thoracic cavity. The possible mechanism, consequences, prevention and management discussed in this report.

Association of endometrioma with ovarian teratoma and mucinous cystadenoma in a patient diagnosed with endometriosis: A case report

BACKGROUND

Co-occurrence of different tumor types in a same patient’s ovaries diagnosed with endometriosis is a rare phenomenon.

CASE SUMMARY

In this article we present an uncommon association of three distinct ovarian pathologies in a same woman presenting with adnexal mass. A 31-year-old nulliparous woman with a large persistent adnexal mass underwent laparoscopic surgery. Imaging demonstrated a multi-cystic mass with internal echoes. Tumor markers were within normal range. Based on histopathologic assessment, benign mucinous cystadenoma and mature cystic teratoma of the right ovary together with endometrioma of left ovary were revealed.

CONCLUSION

In cases of large adnexal mass, the of existence of more than one tumor type and the involvement of the contralateral ovary is possible. Also, the possibility of concurrent underlying malignancy or diminished ovarian reserve should be kept in mind.

Whole-Genome and Segmental Homozygosity Confirm Errors in Meiosis as Etiology of Struma Ovarii

Strumae ovarii are neoplasms composed of normal-appearing thyroid tissue that occur within the ovary and rarely spread to extraovarian sites. A unique case of struma ovarii with widespread dissemination detected 48 years after removal of a pelvic dermoid provided the opportunity to reexamine the molecular nature of this form of neoplasm. One tumor, from the heart, consisting of benign thyroid tissue was found to have whole-genome homozygosity. Another tumor from the right mandible composed of malignant-appearing thyroid tissue showed whole-genome homozygosity and a deletion of 7p, presumably the second hit that transformed it into a cancerous tumor. Specimens from 2 other cases of extraovarian struma confined to the abdomen and 8 of 9 cases of intraovarian struma showed genome-wide segmental homozygosity. These findings confirm errors in meiosis as the origin of struma ovarii. The histological and molecular findings further demonstrate that even when outside the ovary, strumae ovarii can behave nonaggressively until they receive a second hit, thereafter behaving like cancer.

Pediatric whole body MRI detects causative ovarian teratoma in opsoclonus myoclonus syndrome

Opsoclonus Myoclonus Syndrome (OMS, or Opsoclonus Myoclonus Ataxia) is a rare condition that presents with saccadic movements of the eyes, cerebellar ataxia, and choreiform movements of the limbs. While previous reports have described the use of ultrasound, CT, FDG-PET and traditional focused MRI for localization of OMS-associated masses, whole body MRI has not previously been reported for this purpose. Here we describe a 16-year-old patient who exhibited OMS and underwent whole body MRI to rule out the more commonly associated neuroblastoma. An ovarian mass was discovered, resected, and pathology confirmed benign teratoma - there was subsequent resolution of symptoms after complete surgical resection. Whole body MRI should be considered in pediatric cases of OMS due to the paraneoplastic nature of the disease with associated tumor, high sensitivity of disease detection, lack of ionizing radiation, excellent tissue resolution and demonstrated effectiveness in pediatric imaging.

Giant mature teratoma in thymic tissue removed with uniportal vats approach

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Teratomas are tumours composed by different tissues derived from one or more of the three primitive germ cell layers. The frequency of mediastinal teratomas ranged from 1 to 5 %, in most cases with localization in the anterior/superior mediastinum.

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VATS technique is minimally invasive, and it is characterized by a shorter recovery period, a minor blood loss and a shorter hospital stay. VATS has been advocated since 2010 for pulmonary resections, but today it is also performed for mediastinal intervention and a series of reports have demonstrated that it is feasible and safe.

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We demonstrate that uniportal VATS could be used also to remove mediastinal giant mass, without complications for patients, with a reduction hospital stay, less post-operative pain and better cosmetic results.

Introduction

Teratomas are tumours composed by different tissues derived from one or more of the three primitive germ cell layers. The frequency of mediastinal teratomas ranged from 1 to 5 %, in most cases with localization in the anterior/superior mediastinum.

Presentation of case

We report a case report of a 29 years old male who presented an occasional and asymptomatic mediastinal mass.

Computer Tomography (CT) scan showed a 6.8 × 4.5 cm mass in the anterior mediastino, located below the left brachio-cephalic vein, next to aortic arch and left pulmonary artery. Complete excision of the mass “en block” with anterior mediastinal adipose tissue was achieved, using uniportal VATS approach. The postoperative course was regular, without air leak or other pulmonary complication.

Discussion

VATS technique is minimally invasive and, moreover, it is characterized by a shorter recovery period, a minor blood loss and a shorter hospital stay. VATS has been advocated since 2010 for pulmonary resections, but today it is also performed for mediastinal intervention and a series of reports have demonstrated that it is feasible and safe.

Conclusion

The report aims at pointing out the possibility of undergoing this kind of surgery not only in case of pulmonary mass (on which the previous literature has focused) but also when mediastinum lesions occur, as in our case.

Incidence of anti-NMDAR encephalitis in patients undergoing resection of ovarian teratoma in a single institution

OBJECTIVE

The objective of this study was to determine the incidence of anti-NMDAR encephalitis in patients in whom a teratoma was removed. As far as we know, there has been no report on the incidence of anti-NMDAR encephalitis in patients in whom a teratoma was removed.

METHODS

This study was a single-institutional observational study. We enrolled patients who were diagnosed with teratoma in the Department of Pathology, Sapporo City General Hospital during a nine-year period between January 2008 and December 2016.

RESULTS

In Sapporo City General Hospital, 6 NMDAR encephalitis cases were detected during the 9-year period. In the same 9-year period, a pathological diagnosis of teratoma was made in 343 cases in the hospital. Anti-NMDAR encephalitis patients with a teratoma accounted for only 1.17% of all teratoma patients. Three of the 4 anti-NMDAR encephalitis patients with a teratoma underwent second removal of a teratoma, and no nervous tissue was detected pathologically.

CONCLUSIONS

In this study, we determined the association between teratoma with anti-NMDAR encephalitis and teratoma without anti-NMDAR encephalitis in cases in a single institution. As far as we know, this report is the first report on the incidence of anti-NMDAR encephalitis in teratoma patients.

Germ Cell Tumors of the Female Genital Tract

Ovarian germ cell tumors are a histologically diverse group of neoplasms with a common origin in the primitive germ cell. The vast majority are represented by mature cystic teratoma. In the minority are malignant germ cell tumors including immature teratoma, dysgerminoma, yolk sac tumor, embryonal cell carcinoma, and choriocarcinoma. This article reviews the histologic and immunohistochemical features of the most common ovarian germ cell tumors. The differential diagnoses for each are discussed.

Mature Nasopharyngeal Teratoma in a Neonate: Case Report and a Review of Literature

Teratomas are true neoplasms that contain tissues foreign to the site in which they arise. They are derived from germ cells with components of the three embryonic layers (ectoderm, mesoderm and endoderm). The present report is about a 10 day old neonate with teratoma arising from the nasopharyngeal surface of the soft palate, which was successfully removed.

Spinal Intradural Extramedullary Dermoid Cyst

BACKGROUND

Dermoid cysts are benign congenital tumors that develop early in life. These tumors are classified by the presence of all 3 germ layers. Spinal intradural extramedullary teratoma is a rare disease, which is more common in children under 5 years of age than in adults.

CASE DESCRIPTION

A 12-year-old girl with a dermoid cyst at the lower lumbar level presented with 2-month low back pain and intermittent lower extremity radicular symptoms on the right side. Magnetic resonance imaging scan of the spine revealed an intradural extramedullary mass lesion at L4-5. Surgical excision of the cyst was successfully performed. Surgical and histopathologic findings confirmed extramedullary ruptured matured teratoma. Postoperatively, the patient had remarkable clinical improvement.

CONCLUSIONS

Although dermoid cysts are uncommon, they should be considered in the differential diagnosis of spinal lesions in patients with lower back pain. It can be successfully treated with surgical excision.

Clinicopathological characteristics of dysplastic teratomous neuroglia with anti-N-methyl-d-aspartate receptor encephalitis

In this study, we investigated whether unique pathological characteristics exist in teratomas that can trigger autoimmune anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis. We compared a case of retroperitoneal teratoma associated with anti-NMDAR encephalitis and four control cases. The encephalitis-positive case showed that (i) more dysplastic neuroglia with higher Ki-67 labeling index values than the control cases, which met the diagnostic criteria of astrocytoma, (ii) the NMDAR subunit NR1 was expressed more abundantly in neuroglial tissue where many neuroglial cells co-expressed glial fibrillary acidic protein (GFAP) and NR1 and formed abnormally large cellular masses, (iii) intense NR1 expression occurs in squamous epithelium near neuroglial tissue and lymphocyte infiltration. This study showed that dysplastic neuroglial tissue resembling central nervous system tumors, which might promote autoimmunity, distinguished the case with NMDAR encephalitis from the controls. Additionally, abnormal expression of NR1 occurs in non-neural tissues and could be triggered by inflammation and participate in autoimmunity.

A unique uterine cervical "teratocarcinosarcoma": a case report

Background

Teratocarcinosarcoma (TCS) is a rare aggressive tumor of the nasal cavity and paranasal sinuses and has both epithelial and two or more mesenchymal components. In other organs, 5 cases of ovarian tumors closely resembling TCS have been reported; however, there has been no published case of cervical TCS. Herein, we describe a unique case of cervical tumor that had carcinosarcomatous and teratomatous features, resembling a sinonasal TCS.

Case presentation

A 45-year-old woman presented to our hospital for evaluation of a cervical lesion. The gynecologist found a large polypoid mass, whose biopsy showed glandular components of probable germ cell origin based on the immunohistochemical features. The patient underwent total hysterectomy with bilateral salpingo-oophorectomy. The cervical polypoid mass was found to consist of both epithelial and mesenchymal tissues, including immature glandular structure resembling fetal enteric tubules, neuroepithelial cells, hyaline cartilage, and rhabdomyosarcoma cells. This tumor was diagnosed as TCS of the uterine cervix. Following the surgery, the patient received radiotherapy and has been free of disease for 13 months.

Conclusion

This is the first case report of cervical TCS. The tumor is thought to be histogenetically less associated with HPV infection, and its teratomatous components with an absence of cytogenetic abnormalities (including isochromosome 12p (i(12p)) suggest a analogous histogenesis compared to pure mature or immature teratoma.

Squamous cell carcinoma as a somatic-type malignancy in an extragonadal immature teratoma of the sinonasal region

Somatic-type malignancy arising in a teratoma of the sinonasal region is extremely unusual, creating a diagnostic dilemma. There are no definite guidelines for management of such cases. A 15-year-old male with a maxillary mass was misdiagnosed as angiomyolipoma, maxillary carcinoma, mucoepidermoid carcinoma, and teratocarcinosarcoma, followed by the final diagnosis of squamous cell carcinoma arising in an immature teratoma. He received neoadjuvant chemotherapy, followed by surgery and chemo-radiotherapy, and is disease-free at 21 months. This case highlights the difficulty faced when diagnosing neoplasms unusual to the head and neck region, particularly on small biopsies, and good outcome following appropriate multimodality management.

Derivation of neural stem cells from human teratomas

Human teratoma is a germ cell tumor that contains normal tissues (e.g., hair, skin or cartilage) differentiated from embryonal germ layers. Because of the feature of this tumor, we hypothesized that human teratomas contain multipotent stem cells that can develop into various non-cancerous normal tissues. In this study, we cultured neurospheres originally derived from a human infantile teratoma tissue, and the sphere cells were found to possess the characteristics of neural stem cells. Tumor tissues were obtained from an infantile immature teratoma at the time of surgical resection. In the primary cell culture, colonies were formed in two weeks and were individually cultured in serum-free conditioned neural stem cell medium (NSC medium). Colonies changed into spheres and grew in smooth round forms, or attached to the bottom of the dishes and extended processes and filaments around. Sphere cells were dissociated into single cells, and new spheres (secondary spheres) were formed in NSC medium. Cell differentiation was induced by culturing cells in serum-containing medium (differentiation medium), as cells spread and attached to the bottom of dishes and changed form. The expression of Nestin, Sox2, CXCR4, and (stem cell markers), β3-tubulin (a neural marker) GFAP (a glial marker) CNPase, SOX10 (oligodendrocyte markers) and NF-L in cells was analyzed by immunofluorescence and a Q-PCR. Nestin, SOX2, CXCR4 were abundant in both primary and secondary spheres. Neural and glial markers (β3-tubulin and GFAP, respectively) were increased in cells cultured in differentiation medium while stem cell markers were diminished. The oligodendrocyte markers SOX10 and CNPase were also found in both spheres and differentiated cells. In conclusion, spheres with the characteristics of neural stem cells were obtained from the primary culture of a human infantile teratoma. These spheres are considered to have the potential to undergo a natural course of neural development in humans.

Trismus as a Presenting Symptom in a Case of Progressive Encephalopathy with Rigidity and Myoclonus

In this report we present a clinical case of trismus. The patient in question showed symptoms of trismus for 3 days, rapidly leading to respiratory insufficiency. Afterwards she developed myoclonus and progressive encephalopathy. Neurological workup showed no relevant abnormalities. A CT of the abdomen revealed a mass in the lower abdomen, which turned out to be an ovarian teratoma. Progressive encephalopathy with rigidity and myoclonus (PERM) was diagnosed clinically. Treatment with corticosteroids, benzodiazepines, and levetiracetam did not ameliorate the patient's condition. Only after the introduction of plasmapheresis was there a spectacular improvement in her clinical state. In this case we could not detect associated antibodies. The most likely cause of PERM is paraneoplastic disease secondary to ovarian teratoma. This type of tumor has been associated with multiple paraneoplastic neurological conditions, but this is the first case associated with PERM. To date there is only one publication on trismus as a sole presenting sign, with a quite similar disease course.

Huge ovarian mature cystic teratoma with gliomatosis peritonei and massive ascites in a postmenopausal woman

Teratoma of the ovary is the most frequently encountered germ cell tumor. It usually occurs in young women. Gliomatosis peritonei (GP) is mature neural glial tissue implanted onto the peritoneal surface. We present a case of a mature teratoma accompanied by GP and massive ascites in postmenopausal women. A 54-year-old, G0P0, woman presented in the gynecology outpatient department with abdominal distension for 6 months. Computed tomography scan of the abdomen and pelvis displayed an ovarian mass about 20 cm × 18 cm with peritoneal seeding, ascites, and enlarged paraaortic lymph nodes. A total hysterectomy and bilateral adnexectomy were performed. The pathology showed the left ovary contained a dermoid cyst. The biopsy of the peritoneal nodule displayed glial tissue confirming the diagnosis of GP. The patient remained in good condition 6 months postoperatively. We suggest GP be considered in patients presenting with teratomas and massive ascites. The radiological diagnosis is challenging due to the rarity of GP. Continued follow-up of patients with teratomas and GP is mandatory due to the potential of malignant transformation.

Predicting differentiation potential of human pluripotent stem cells: Possibilities and challenges

The capability of human pluripotent stem cell (hPSC) lines to propagate indefinitely and differentiate into derivatives of three embryonic germ layers makes these cells be powerful tools for basic scientific research and promising agents for translational medicine. However, variations in differentiation tendency and efficiency as well as pluripotency maintenance necessitate the selection of hPSC lines for the intended applications to save time and cost. To screen the qualified cell lines and exclude problematic cell lines, their pluripotency must be confirmed initially by traditional methods such as teratoma formation or by high-throughput gene expression profiling assay. Additionally, their differentiation potential, particularly the lineage-specific differentiation propensities of hPSC lines, should be predicted in an early stage. As a complement to the teratoma assay, RNA sequencing data provide a quantitative estimate of the differentiation ability of hPSCs in vivo. Moreover, multiple scorecards have been developed based on selected gene sets for predicting the differentiation potential into three germ layers or the desired cell type many days before terminal differentiation. For clinical application of hPSCs, the malignant potential of the cells must also be evaluated. A combination of histologic examination of teratoma with quantitation of gene expression data derived from teratoma tissue provides safety-related predictive information by detecting immature teratomas, malignancy marker expression, and other parameters. Although various prediction methods are available, distinct limitations remain such as the discordance of results between different assays and requirement of a long time and high labor and cost, restricting their wide applications in routine studies. Therefore, simpler and more rapid detection assays with high specificity and sensitivity that can be used to monitor the status of hPSCs at any time and fewer targeted markers that are more specific for a given desired cell type are urgently needed.

The RNA-binding protein DND1 acts sequentially as a negative regulator of pluripotency and a positive regulator of epigenetic modifiers required for germ cell reprogramming

The adult spermatogonial stem cell population arises from pluripotent primordial germ cells (PGCs) that enter the fetal testis around embryonic day (E)10.5. PGCs undergo rapid mitotic proliferation, then enter prolonged cell cycle arrest (G1/G0), during which they transition to pro-spermatogonia. In mice homozygous for the Ter mutation in the RNA-binding protein Dnd1 (Dnd1Ter/Ter ), many male germ cells (MGCs) fail to enter G1/G0 and instead form teratomas: tumors containing many embryonic cell types. To investigate the origin of these tumors, we sequenced the MGC transcriptome in Dnd1Ter/Ter mutants at E12.5, E13.5 and E14.5, immediately prior to teratoma formation, and correlated this information with DO-RIP-Seq-identified DND1 direct targets. Consistent with previous results, we found DND1 controls downregulation of many genes associated with pluripotency and active cell cycle, including mTor, Hippo and Bmp/Nodal signaling pathway elements. However, DND1 targets also include genes associated with male differentiation, including a large group of chromatin regulators activated in wild-type but not mutant MGCs during the E13.5 and E14.5 transition. Results suggest multiple DND1 functions and link DND1 to initiation of epigenetic modifications in MGCs.