Structure-Activity Relationship Analysis of YM155 for Inducing Selective Cell Death of Human Pluripotent Stem Cells

Despite great potential for regenerative medicine, the high tumorigenic potential of human pluripotent stem cells (hPSCs) to form undesirable teratoma is an important technical hurdle preventing safe cell therapy. Various small molecules that induce the complete elimination of undifferentiated hPSCs, referred to as "stemotoxics," have been developed to facilitate tumor-free cell therapy, including the Survivin inhibitor YM155. In the present work, based on the chemical structure of YM155, total 26 analogs were synthesized and tested for stemotoxic activity toward human embryonic stem cells (hESCs) and induced PSCs (iPSCs). We found that a hydrogen bond acceptor in the pyrazine ring of YM155 derivatives is critical for stemotoxic activity, which is completely lost in hESCs lacking SLC35F2, which encodes a solute carrier protein. These results suggest that hydrogen bonding interactions between the nitrogens of the pyrazine ring and the SLC35F2 protein are critical for entry of YM155 into hPSCs, and hence stemotoxic activity.

Teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis: A case report and literature review

RATIONALE

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is an autoimmune disease associated with the NMDA receptor and has a good response to treatment. However, only few cases related to teratoma have been reported. Here, we report a case of teratoma-associated anti-NMDAR encephalitis.

PATIENT CONCERNS

A 25-year-old woman presenting with fever for 20 days and psychiatric symptoms for 9 days was admitted to the hospital. The patient progressed to a minimally conscious state consistent with encephalitis.

DIAGNOSIS

Considering the possibility of autoantibody-mediated encephalitis, laboratory tests were conducted to detect anti-NMDAR antibodies in cerebrospinal fluid and serum. Results confirmed the diagnosis of anti-NMDAR encephalitis. Furthermore, gynecological ultrasound investigation detected teratoma in the left ovary.

INTERVENTIONS

After resection of the teratoma with laparoscopic adnexectom, the patient was treatment with immunosuppressive therapy.

OUTCOMES

The patient recovered gradually and was discharged 2 months after the operation.

LESSONS

Anti-NMDAR encephalitis remains difficult to diagnose because of its vague manifestations, and no clinical practice guidelines for prevention and treatment of the disease have been established yet. The clinical data of a case of teratoma-related anti-NMDAR encephalitis were analyzed, and relevant studies were reviewed.

Encephalitis on deployment in Kenya: think beyond the infections

A 34-year-old female soldier presented with fever and behavioural changes while deployed in Kenya and was diagnosed with encephalitis. The patient underwent urgent aeromedical evacuation to the Queen Elizabeth Hospital, Birmingham for further management. Microbiology tests excluded common infectious causes that are endemic in the East Africa region. However, an autoantibody screen was positive for antibodies against the N-methyl-D-aspartate receptor (NMDAR). Full body imaging confirmed the presence of limbic encephalitis and an ovarian mass suggestive of a teratoma. The patient was diagnosed with ovarian teratoma-associated anti-NMDAR encephalitis, a potentially fatal disease. The patient underwent surgery to remove the teratoma and commenced immunotherapy with steroids, plasma exchange and rituximab. This case highlights the diagnostic challenges of fever with behavioural changes in military personnel deployed in a tropical environment.

Opsoclonus Myoclonus Syndrome Due to an Ovarian Teratoma: A Case Report and Review of Literature

The importance of ovarian teratoma as a cause of opsoclonus myoclonus ataxia syndrome (OMAS) and other paraneoplastic syndromes continues to be underestimated. A strong suspicion and appropriate diagnosis remain keys to successful outcome of paraneoplastic OMAS with ovarian teratoma. We report a 14-year-old girl with paraneoplastic OMAS in association with an ovarian teratoma who improved completely following resection of tumour as well as immunotherapy and review the literature briefly.

The role of immunohistochemical examination in diagnosis of papillary thyroid cancer in struma ovarii

INTRODUCTION

Struma ovarii (SO) is a monodermal teratoma in which thyroid tissue comprises more than 50% of the tumour. Papillary thyroid cancer (PTC) in SO is a rare finding, as only 5% of SO cases undergo malignant transformation. Malignant SO is usually asymptomatic and infrequently diagnosed preoperatively. Because of its rarity, there is no consensus about diagnosis and management, while treatment and follow-up procedures are not clearly established.

MATERIAL AND METHODS

Herewith, we report two cases of PTC in SO. The first patient was a 25-year-old woman diagnosed with bilateral ovarian tumours. The second patient, 19-year-old woman, presented with unilateral ovarian mass. Both patients were qualified for surgical excision of the tumours. Histopathological specimens underwent both conventional histopathological assessment and immunohistochemical staining.

RESULTS

In the first patient histopathology revealed SO with two foci of PTC. Immunohistochemically a positive expression of CK7, CK19, p63 and thyroglobulin (Tg) confirmed the diagnosis. She underwent total thyroidectomy in 2016 in order to enable ablative radioiodine therapy and facilitate further thyroglobulin monitoring. Unfortunately, the patient was lost from follow-up. In the second patient, histopathological diagnosis was follicular variant of PTC in SO. Postoperatively, a pelvic CT revealed osteolytic lesion 6 cm in size, being a metastatic change. The patient underwent unilateral ovariectomy, total thyroidectomy and multiple cycles of radioiodine therapy. Currently, 9 years following the diagnosis, the patient achieved disease remission.

CONCLUSIONS

PTC in SO still remains a diagnostic and therapeutic challenge. Immunostaining for CK7, CK19, p63 and Tg might be helpful in histopathological diagnosis. The decision on the need of total thyroidectomy and radioiodine therapy should be made individually. However, thyroid remnant ablation increases the sensitivity and specificity of follow-up testing using serum Tg level as a tumour marker.

Intratubular Teratoma: A Rare Form of Testicular Germ Cell Neoplasia

Germ cell neoplasia in situ is the initial manifestation for invasive germ cell tumor. Further progression will result in intratubular germ cell tumor with the majority being intratubular seminoma or intratubular embryonal carcinoma. Intratubular teratoma in the testis is exceptionally rare with no well-documented cases to our knowledge. In this article, we report a case of an intratubular teratoma adjacent to mixed germ cell tumor in the testis. The patient is a 34-year-old male who presented with a palpable right testicular mass and underwent right radical orchiectomy. Gross examination of the testis revealed 2.0-cm tan, well-circumscribed, firm, and nodular mass at the inferior pole. Microscopic examination revealed a mixed germ cell tumor, predominantly seminoma (95%) with embryonal carcinoma (4%) and teratoma (1%). There is also germ cell neoplasia in situ, intratubular seminoma, and intratubular teratoma at the periphery of the tumor. Tubules with intratubular teratoma were filled by neoplastic squamous cells with a single layer of germ cell neoplasia in situ at the periphery. Adjacent to the intratubular teratoma was seminoma, embryonal carcinoma, and invasive teratoma. Immunohistochemical stains showed the neoplastic squamous cells in the tubule to be positive for p40 and negative for OCT34 and D2-40. The single layer of germ cell neoplasia in situ at the periphery of the intratubular teratoma was negative for p40 and positive for OCT34 and D2-40. Although teratoma is a common component in an adult germ cell tumor, an intratubular manifestation is exceptional. The present case illustrates this rare finding.

Mixed germ cell tumor composed of a tridermic testicular teratoma and seminoma in a rooster

A 5-y-old backyard Araucana-Americana rooster was presented to the regional diagnostic laboratory with a history of progressive lethargy and respiratory signs. Autopsy revealed a single large mass of testicular origin in the coelomic cavity, causing compression of other organs. Histologically, the mass was 1 neoplasm with mixed components of 2 different germ cell tumors, namely a teratoma composed of elements of all 3 primordial germ cell lines (ectoderm, mesoderm, and endoderm), and a seminoma consisting of round or polygonal cells arranged in sheets supported by a scant fibrovascular stroma. Teratomas and seminomas are both considered to be uncommon neoplasms in poultry medicine. A testicular teratoma is composed of mature embryonic tissue derived from at least 2 of the 3 germinal layers. Seminomas and teratomas both arise from the germinal epithelium of seminiferous tubules and are classified as germ cell tumors. This neoplastic mass thus is a rare case of a mixed germ cell tumor.

Perinatal intracardiac teratoma: unusual presentation and review of the literature

Intracardiac teratomas are rare primary tumours. We report the case of an infant prenatally diagnosed with an isolated multi-cystic mass developed in the right ventricle causing neonatal refractory ventricular arrhythmia. Despite rescue extracorporeal support and partial surgical resection, he died as almost all the previous reported perinatal intracardiac teratomas whatever the prenatal tolerance and the size of the tumour. The common poor outcome of fetal intracardiac teratomas should be known when counselling parents during pregnancy.

A case report of a giant mature teratoma of the thyroid gland in a young girl

RATIONALE

Teratomas are extremely rare in the thyroid gland. A cervical teratoma presenting as a cystic or mixed thyroid lesion can be easily confused with a thyroglossal duct cyst. It is difficult for pediatricians to differentiate between these 2 types of lesions.

PATIENTS CONCERNS

A 2-year-old girl who presented a growing thyroid mass for 14 months showed a mass in her left thyroid lobe under contrast-enhanced computed tomography (CT).

DIAGNOSIS AND INTERVENTIONS

Ultrasonography found a mass of 5 × 3.5 cm within the left lobe of the thyroid gland, and the sonogram revealed areas with echo-free and mixed-echo patterns. There was no accumulation of technetium-99m pertechnetate on the thyroid scintigraphy (cold thyroid nodule). CT scan showed a mass (5.0 × 3.0 × 2.5 cm in size) that extended from the left thyroid lobe to the anterior mediastinum with no evident enhancement and clear margins that contained calcifications. Complete excision without intraoperative capsule disruption was achieved. Histologically, the thyroid mass was diagnosed as a mature teratoma.

OUTCOMES

The postoperative course was uneventful after follow-ups for 2 years, and the patient had no inflammatory signs or evidence of recurrence.

LESSONS

Thyroid teratoma is rare in infants and is usually benign; however, some thyroid teratomas are malignant and inclined to relapse. The authors emphasize that thyroid teratomas in children should be included in the differential diagnosis of cystic lesions located in the head and neck area. Complete resection is essential for good outcomes. In addition, long-term follow-ups are warranted to follow the complications of the malignant or recurrent disease.

A Double Fail-Safe Approach to Prevent Tumorigenesis and Select Pancreatic β Cells from Human Embryonic Stem Cells

The transplantation of human embryonic stem cell (hESC)-derived insulin-producing β cells for the treatment of diabetes is finally approaching the clinical stage. However, even with state-of-the-art differentiation protocols, a significant percentage of undefined non-endocrine cell types are still generated. Most importantly, there is the potential for carry-over of non-differentiated cell types that may produce teratomas. We sought to modify hESCs so that their differentiated progeny could be selectively devoid of tumorigenic cells and enriched for cells of the desired phenotype (in this case, β cells). Here we report the generation of a modified hESC line harboring two suicide gene cassettes, whose expression results in cell death in the presence of specific pro-drugs. We show the efficacy of this system at enriching for β cells and eliminating tumorigenic ones both in vitro and in vivo. Our approach is innovative inasmuch as it allows for the preservation of the desired cells while eliminating those with the potential to develop teratomas.

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hESCs were engineered with suicide genes for safety and differentiation efficiency

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One cassette is exclusively expressed in teratogenic cells (safety)

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Another is selectively excised out in hESC-derived pancreatic β cells (selectivity)

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Our strategy allows for hESC-derived tumors to be prevented or ablated in vivo

Pharyngeal hairy polyps: Case series and literature review

It was aimed to report 5 cases of pharyngeal hairy polyps, and to summarize the characteristics combined with literature review.Five cases with pathological diagnosis of pharyngeal hair polyps were diagnosed and treated in our department from June, 2006 to October, 2016, and retrospective analysis of their clinical data was performed. Among the 5 cases, there were 1 male and 4 female, with the age of 2 days to 26 months old. After birth, these patients were accompanied by stridor, difficulty breathing, snoring, feeding difficulties, and slow weight gain.Gray mass in the stem original from the pharynx was found in all 5 cases, with the surface hair-covering. The polyp resections were performed under general anesthesia, with the complete removal of polyp along the pars basilaris during surgery smoothly. The operation during was 5 to 20 minute, with an average of 12 minute, and there was little hemorrhage during operation. Symptoms disappeared completely after the surgery, and follow-up was performed for 1 year without recurrence shown.Pharyngeal hairy polyp is a rare non-malignant clinical disease, mainly caused by symptoms in respiratory tract obstruction. Complete removal of polyps along the pars basilaris is an effective treatment, with no recurrence case reported after surgery.

Targeting RNA helicase DDX3 in stem cell maintenance and teratoma formation

DDX3 is an RNA helicase that has antiapoptotic properties, and promotes proliferation and transformation. Besides the role of DDX3 in transformed cells, there is evidence to indicate that DDX3 expression is at its highest levels during early embryonic development and is also expressed in germ cells of adults. Even though there is a distinct pattern of DDX3 expression during embryonic development and in adults, very little is known regarding its role in embryonic stem cells and pluripotency. In this work, we examined the relationship between DDX3 and human embryonic stem cells and its differentiated lineages. DDX3 expression was analyzed by immunohistochemistry in human embryonic stem cells and embryonal carcinoma cells. From the data obtained, it was evident that DDX3 was overexpressed in undifferentiated stem cells compared to differentiated cells. Moreover, when DDX3 expression was abrogated in multiple stem cells, proliferation was decreased, but differentiation was facilitated. Importantly, this resulted in reduced potency to induce teratoma formation. Taken together, these findings indicate a distinct role for DDX3 in stem cell maintenance.

An Unusual Presentation of Ovarian Fibroma Originating from an Autoamputated Ovary

We describe an extremely rare case of an unusually presented ovarian fibroma adherent to the sigmoid colon originating from an autoamputated ovary. A 64-year-old woman was referred to our hospital with an abnormal shadow that was approximately 4 cm in diameter in the pelvic cavity detected on abdominal X-ray imaging. Computed tomography demonstrated an irregularly shaped tumor with calcification in the pelvic cavity. Laparoscopy revealed that the tumor was adherent to the surface of the sigmoid colon with a discontinuous shell and empty cavity. The left ovary was lacking, although the left salpinx and right adnexa were in their normal locations. The tumor was carefully resected with cutting of the serosa of the sigmoid colon. The serosal defect was repaired with sutures. Postoperative histopathological diagnosis was old fibroma with calcification. To the best of our knowledge, this is the first reported case of extragonadal ovarian tumor originating from an autoamputated ovarian fibroma.

Ovarian teratoma removed by laparoscopic ovariectomy in a dog

An elective laparoscopic ovariectomy on a healthy dog revealed a cystic structure in the left ovary. The surgical procedure was successful. Histopathological examination showed the presence of a teratoma adjacent to the ovary. To the best of the authors' knowledge, this is the first reported case of an ovarian teratoma removed by laparoscopic ovariectomy in a dog by using a multiport laparoscopic ovariectomy technique.

A Case Report of Intrapulmonary Teratoma in the Right Upper Lung Zone in a 35-year-old Female Patient

Teratomas are rare germ cell tumors usually found in the gonads. Extra-gonadal teratomas are especially rare, mostly occurring in the thorax. Only a few cases of intrathoracic teratomas have been reported in medical literature and most reported were located in the mediastinum. An additional intrathoracic location for teratoma occurrence is in the pulmonary system, most commonly in the upper lobe of the left lung. In this report, we describe a case of a 35-year-old woman diagnosed with an intrapulmonary mature teratoma found in the right upper lobe. A 35-year-old Saudi female presented with a chief complaint of a three-week history of dry cough. Chest X-ray revealed a right-sided para-pericardial mass in the anterior mediastinum and a significant decrease in the size of the right middle lobe opacity. Subsequently, a chest computed tomography (CT) was performed and revealed a cystic mass in the right lung, which required removal by surgical intervention. The surgery was performed via a thoracoscopic approach and the tumor was excised with no complications. Intrapulmonary teratomas (IPT) usually present with vague and non-specific symptoms such as cough, hemoptysis, and chest pain. It is a rare condition without diagnostic features detected preoperatively, save for trichoptysis which is reported in approximately 13% of the cases. We report a rare appearance of mature IPT in the right upper lung zone which is an unusual location.

Direct in vivo application of induced pluripotent stem cells is feasible and can be safe

Increasing evidence suggests the consensus that direct in vivo application of induced pluripotent stem cells (iPSCs) is infeasible may not be true. Methods: Teratoma formation and fate were examined in 53 normal and disease conditions involving brain, lung, liver, kidney, islet, skin, hind limb, and arteries. Results: Using classic teratoma generation assays, which require iPSCs to be congregated and confined, all mouse, human, and individualized autologous monkey iPSCs tested formed teratoma, while iPSC-derived cells did not. Intravenously or topically-disseminated iPSCs did not form teratomas with doses up to 2.5×10⁸ iPSCs/kg and observation times up to 18 months, regardless of host tissue type; autologous, syngeneic, or immune-deficient host animals; presence or absence of disease; disease type; iPSC induction method; commercial or self-induced iPSCs; mouse, human, or monkey iPSCs; frequency of delivery; and sex. Matrigel-confined, but not PBS-suspended, syngeneic iPSCs delivered into the peritoneal cavity or renal capsule formed teratomas. Intravenously administered iPSCs were therapeutic with a dose as low as 5×10⁶/kg and some iPSCs differentiated into somatic cells in injured organs. Disseminated iPSCs trafficked into injured tissue and survived significantly longer in injured than uninjured organs. In disease-free animals, no intravenously administered cell differentiated into an unwanted long-lasting cell or survived as a quiescent stem cell. In coculture, the stem cell medium and dominant cell-type status were critical for iPSCs to form cell masses. Conclusion: Teratoma can be easily and completely avoided by disseminating the cells. Direct in vivo iPSC application is feasible and can be safe.

Germ Cell Tumors in Dysgenetic Gonads

This review describes the germ cell neoplasms that are malignant and most commonly associated with several types of gonadal dysgenesis. The most common neoplasm is gonadoblastoma, while others including dysgerminomas, yolk-sac tumors and teratomas are rare but can occur. The purpose of this review is to evaluate the incidences of these abnormalities and the circumstances surrounding these specific tumors.According to well-established methods, a PubMed systematic review was performed, to obtain relevant studies published in English and select those with the highest-quality data.Initially, the first search was performed using gonadal dysgenesis as the search term, resulting in 12,887 PubMed papers, published, from 1945 to 2017. A second search using ovarian germ cell tumors as the search term resulted in 10,473 papers, published from 1960 to 2017. Another search was performed in Medline, using germ cell neoplasia as the search term, and this search resulted in 7,560 papers that were published between 2003 to 2016, with 245 new papers assessing gonadoblastomas.The higher incidence of germ cell tumors in gonadal dysgenesis is associated with a chromosomal anomaly that leads to the absence of germ cells in these gonads and, consequently, a higher incidence of neoplasms when these tumors are located inside the abdomen. Several hypotheses suggest that increased incidence of germ cell tumors involves all or part of the Y chromosome or different genes.

The MicroRNA-371 Family as Plasma Biomarkers for Monitoring Undifferentiated and Potentially Malignant Human Pluripotent Stem Cells in Teratoma Assays

Predicting developmental potency and risk of posttransplantation tumor formation by human pluripotent stem cells (hPSCs) and their derivatives largely rely on classical histological analysis of teratomas. Here, we investigated whether an assay based on microRNAs (miRNA) in blood plasma is able to detect potentially malignant elements. Several hPSCs and human malignant germ cell tumor (hGCT) lines were investigated in vitro and in vivo after mouse xenografting. The multiple conventional hPSC lines generated mature teratomas, while xenografts from induced hPSCs (hiPSCs) with reactivated reprogramming transgenes and hGCT lines contained undifferentiated and potentially malignant components. The presence of these elements was reflected in the mRNA and miRNA profiles of the xenografts with OCT3/4 mRNA and the miR-371 and miR-302 families readily detectable. miR-371 family members were also identified in mouse plasma faithfully reporting undifferentiated elements in the xenografts. This study demonstrated that undifferentiated and potentially malignant cells could be detected in vivo.

The Psychic Life of Fragments: Splitting from Ferenczi to Klein

The present paper starts from the reflection that there is a curious "phenomenological gap" in psychoanalysis when it comes to processes of splitting and to describing the "life" of psychic fragments resulting from processes of splitting. In simpler terms, we are often in a position to lack a precise understanding of what is being split and how the splitting occurs. I argue that although Melanie Klein's work is often engaged when talking of splitting (particularly through discussions on identification, projection and projective identification), there are some important phenomenological opacities in her construction. I show that by orchestrating a dialogue between Melanie Klein and Sándor Ferenczi, we arrive at a fuller and more substantive conception of psychic splitting and of the psychic life of fragments which are the result of splitting. This is even more meaningful because there are some unacknowledged genealogical connections between Ferenczian concepts and Kleinian concepts, which I here explore. While with Klein we remain in the domain of "good" and "bad" objects-polarised objects which are constantly split and projected-with Ferenczi we are able to also give an account of complicated forms of imitation producing psychic fragments and with a "dark" side of identification, which he calls "identification with the aggressor". While attempting to take steps toward imagining a dialogue between Klein and Ferenczi, I note a certain silent "Ferenczian turn" in a late text by Melanie Klein, "On the Development of Mental Functioning", written in 1958. In particular, I reflect on her reference to some "terrifying figures" of the psyche, which cannot be accounted for simply as the persecutory parts of the super-ego but are instead more adequately read as more enigmatic and more primitive psychic fragments, resulting from processes of splitting.

Adult Thoracic Intradural Exophytic Mature Teratoma: Case Report and Literature Review

Mature thoracic intraspinal teratomas are rare tumors in adults. In this case study, we present a case of intradural, extramedullary teratoma, which was surgically resected. A 50 year old man presented with progressive bilateral leg pain, severe myelopathy and weakness. Magnetic Resonance Imaging (MRI) revealed a cystic mass lesion in the T11-12 region region. Microsurgical resection of the tumor using CO² laser with neuromonitoring was performed. Postoperatively, the patient had a remarkable clinical improvement. Mature spinal teratomas are rare, slow growing spinal tumors. Surgical resection provides excellent recovery, and recurrence rates are low.

Treatment Options for Anti-N-methyl-D-aspartate Receptor Encephalitis

Anti-NMDAR encephalitis is an autoimmune limbic disorder with an unknown cause, which affects mostly young women. Behavioral changes, seizures, orofacial muscle contractions, and memory impairment are usually observed. The variability of the symptoms depends on which part of the brain is inflamed. Treatment options aim to reduce serious neurological damage. Early diagnosis combined with the proper treatment favorably impacts the outcome. In our facility, weekly induction therapy is started pending an investigation into an associated ovarian or other tumor. Two case studies are discussed with favorable outcomes. The first is an outstanding case study with refractory status epilepticus caused by anti-NMDA receptors with benign teratoma which improved following combination therapy with rituximab and cyclophosphamide. There was no response to benzodiazepines and to an abundant number of antiepileptic drugs. Brain magnetic resonance imaging clearly indicated severe brain atrophy in the first case. Serial EEG monitoring showed a multitude of abnormalities. Delta brush activity was interictal and distinctive of anti-NMDAR encephalitis.

Currarino syndrome: repair of the dysraphic anomalies and resection of the presacral mass in a combined neurosurgical and general surgical approach

OBJECTIVEIt is well established that Currarino syndrome (CS) may be associated with spinal dysraphism. Here, the authors report on 10 CS patients with dysraphic anomalies who had undergone a combined neurosurgical and general surgical approach to repair the dysraphic anomalies and resect the presacral mass in a single operation. They discuss the spectrum of spinal dysraphism that may coexist in CS in the context of its developmental etiology.METHODSChildren with a confirmed CS diagnosis who had undergone the combined operative approach were identified from a departmental database. Presenting features were recorded and preoperative imaging was analyzed to record features of the presacral mass and the dysraphic anomalies. The histopathological nature of the resected presacral mass and the outcomes postoperatively and at the last follow-up were reviewed.RESULTSBetween 2008 and 2015, 10 patients presented with CS, 9 with constipation. Median age at the time of surgery was 1.3 years. Six of the 10 patients had anorectal malformation consisting of anal stenosis, rectal stenosis, or imperforate anus. Spinal anomalies included anterior meningocele (5 cases), low-lying conus (8), terminal syrinx (4), fatty filum (5), caudal lipoma (3), and intraspinal cyst (1). In all cases, the lumbosacral spinal canal was accessed via a midline approach with laminoplasty, allowing spinal cord untethering and repair of the dysraphic anomalies. Following dural closure, the incision was extended inferiorly to incorporate a posterior sagittal approach to resect the presacral mass. The histopathological nature of the mass was mature teratoma (8 cases), complex hamartomatous malformation (1), or neurenteric cyst (1). There were no new instances of neurological deterioration, with most instances of persisting morbidity related to constipation (6 cases) or neurogenic bladder dysfunction (8). There were no infective complications, no instances of cerebrospinal fluid fistula, no recurrences of the presacral mass, and no cases of retethering of the spinal cord.CONCLUSIONSAlthough not part of the original triad, spinal dysraphic anomalies are common in CS and in keeping with a disorder of secondary neurulation. Lumbosacral MRI is an essential investigation when CS is suspected. Children are at risk of sphincter impairment due to the anorectal malformation; however, both spinal cord tethering and compression from the presacral mass may further compromise long-term continence. A combined operative approach to repair the dysraphic anomalies and resect the presacral mass is described with good postoperative and long-term outcomes.

Paraneoplastic Teratoma-associated Anti-N-Methyl-D-Aspartate Receptor Encephalitis: The First Published Report from Saudi Arabia

Paraneoplastic teratoma-associated anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis is a lately introduced disease that was first documented in 2007. In a recent systemic review in 2014, only a total of 174 cases of teratoma-associated anti-NMDA receptor encephalitis was reported. Herein, to the best of our knowledge, in Saudi Arabia, we report the first ever case of mature ovarian teratoma-associated anti-NMDA receptor encephalitis in a 21-year-old Saudi woman who presented to clinical attention with a nine-day history of neuropsychiatric symptoms preceded by a two-day flu-like illness. Central nervous system (CNS) examination was remarkable for confusion and an inability to move her lower limbs. Abdominal examination was remarkable for mild right lower quadrant tenderness without palpable organomegaly. Initial laboratory findings were remarkable for high CA-125 level of 205 units/ml (normal: 0 - 35 units/ml) and CA 19-9 level of 121 units/ml (normal: 0 - 37 units/ml). Cerebrospinal fluid (CSF) examination showed lymphocytic pleocytosis and oligoclonal bands. Computed tomography (CT) scan of the abdomen and pelvis showed a 7.2 x 6.3 x 5.5 cm mass of the right ovary that was highly suspicious for a mature teratoma with fat densities and calcified foci. Serum and CSF tested positive for anti-NMDA receptor antibodies. The patient underwent right oophorectomy and the final histopathological diagnosis was confirmed. Postoperatively, the patient had an uneventful postoperative course and did not receive adjuvant secondary immunotherapies. One day following the surgery, her neuropsychiatric symptoms improved dramatically. At a six-month follow-up at the outpatient clinic, the patient was symptom-free

Human Teratoma-Derived Hematopoiesis Is a Highly Polyclonal Process Supported by Human Umbilical Vein Endothelial Cells

Hematopoietic stem cells (HSCs) ensure a life-long regeneration of the blood system and are therefore an important source for transplantation and gene therapy. The teratoma environment supports the complex development of functional HSCs from human pluripotent stem cells, which is difficult to recapitulate in culture. This model mimics various aspects of early hematopoiesis, but is restricted by the low spontaneous hematopoiesis rate. In this study, a feasible protocol for robust hematopoiesis has been elaborated. We achieved a significant increase of the teratoma-derived hematopoietic population when teratomas were generated in the NSGS mouse, which provides human cytokines, together with co-injection of human umbilical vein endothelial cells. Since little is known about hematopoiesis in teratomas, we addressed localization and clonality of the hematopoietic lineage. Our results indicate that early human hematopoiesis is closely reflected in teratoma formation, and thus highlight the value of this model.

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Robust human hematopoiesis in teratomas with co-injected HUVECs in NSGS mice

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Hematopoietic progenitors localize inside vascular structures in teratomas

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CD45⁺ cells are present in mesenchymal tissue in teratomas

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Teratoma formation and subsequent hematopoiesis are polyclonal events

Immune checkpoint inhibitors of CTLA4 and PD-1 for malignant melanoma arising in ovarian cystic teratoma: A case report

RATIONALE

Malignant melanoma (MM) arising in ovarian cystic teratoma (OCT) is a rare disease with poor prognosis. Recently, immune checkpoint inhibitors of cytotoxic T-lymphocyte-associated antigen 4 (CTLA4) and programmed death 1 (PD-1) have shown promising results in MM. Herein we report a case of MM arising in OCT.

PATIENT CONCERNS

A 63-year-old Japanese primigravida had lower abdominal pain. Magnetic resonance imaging revealed the presence of an 85-mm mass at the right ovary.

DIAGNOSES

The patient underwent right salpingo-oophorectomy for right ovarian tumor, and histopathological examinations revealed MM arising in OCT. On immunohistochemical analysis, the tumor cells were positive for HMB-45, Melan A, and S-100 protein, and negative for programmed death-ligand 1 (PD-L1). BRAF gene mutations were not detected by the Real-Time PCR. Two months after surgery, liver metastasis was detected.

INTERVENTIONS

The patient underwent immune checkpoint inhibitors of CTLA4 (ipilimumab) and PD-1 (pembrolizumab and nivolumab). She had interstitial pneumonia associated with ipilimumab, but she safely underwent the immune checkpoint inhibitors therapy along with oral prednisolone. Pembrolizumab, ipilimumab, and nivolumab therapies had poor effect on the tumor.

OUTCOMES

Now, the present case has had tumor-bearing survival for 14 months since the initial diagnosis and 12 months since the detection of liver metastasis.

LESSONS

This is the first case of MM arising in OCT treated by immune checkpoint inhibitors, with information of PD-L1 immunohistochemical expression and adverse events. The present case is the longest survivor following the detection of recurrence among all the previous reports. The long survival and slow-growing tumor in the present case may be associated with no PD-L1 expressions.