A new hypothesis may explain human parthenogenesis and ovarian teratoma: A review study

Parthenogenesis (PG) is a rare phenomenon occurring in humans, and understanding this may help us develop an explanation for such occurrences. Moreover, it may help reveal the cause of idiopathic ovarian teratoma (OT). We aim to explain the occurrence of PG and OT in humans based on a new hypothesis. Previous literature has been searched through relevant scientific websites and international journals on the causes and mechanisms of PG and OT in humans. The previous literature on human PG was sparse and mostly contained case reports. It appears that human PG is not as rare as previously reported but may occur spontaneously, resulting in OT formation. The difference between PG and sexual reproduction is that PG has no embryonic diversity. The biopsied embryonic samples in the PG correspond exclusively to those of the maternal side. Spontaneous PG in humans often degrades or leads to formation of OT. The cause and mechanism of spontaneous PG remain unclear in the available literature. Here, we hypothesized that in some cases the secondary oocyte and first polar body enclosed in the zona pellucida may fuse together to form a single cell that restores the diploid number of chromosomes and initiates cell division to form PG. It may go unnoticed or be represented by the OT. Future studies are recommended to investigate this hypothesis.

It is all about form and function: a new approach to giant neonatal sacrococcygeal teratomas

INTRODUCTION

Giant sacrococcygeal teratomas (GSCTs) involve severe deformation of the buttock region in addition to potential functional impacts. Little interest has been given to improving the aesthetic post-operative appearance in children with these tumours.

METHODS

We describe a new technique for immediate reconstruction of GSCTs using buried dermal-fat flaps and a low transverse scar in the infragluteal fold.

RESULTS

Our technique allows wide exposure for tumour resection and functional restoration of the pelvic floor while placing the scars in anatomical locations and restoring buttock aesthetics including gluteal projection and infragluteal fold definition.

CONCLUSION

Reestablishment of function and form should be kept in mind at initial surgery in GSCT surgery to maximize results and enhance post-operative outcomes.

LEVEL OF EVIDENCE

IV.

Pericardial rupture of mediastinal mature cystic teratoma: An unusual cause of pediatric acute chest pain

A previously healthy 12-year-old girl presented to the emergency department with severe chest pain and dyspnea that woke her from sleep. She had short-term syncope just before the emergency admission. On physical examination, respiratory rate was 26 breaths per minute while resting, and blood pressure was 92/56 mmHg. Other physical examination findings were insignificant. She had no past medical history, and her family history was unremarkable. Laboratory test results showed elevated C-reactive protein (27 mg/L; reference range: <5 mg/L) and white blood cell count (13.7 K/μL; reference range: 4-12 K/μL). Other laboratory test results were within normal limits, including troponin T value (3 ng/L; reference range: 3-14 ng/L). An electrocardiogram showed 1 mm ST-segment elevation in bipolar (D1 and D2) limb leads, and augmented vector foot leads, and echocardiography revealed a complicated pericardial effusion and a suspicious mass adjacent to the left ventricle.

Minimally invasive adnexa-sparing surgery for benign ovarian and paratubal masses in children

BACKGROUND

The precision of minimally invasive surgery (MIS) to resect benign ovarian and paratubal masses while preserving adnexa in children is unclear. This study evaluated the integrity of laparoscopy to spare adnexa while resecting benign pathologies in children.

METHODS

The institutional pathology database was queried to identify patients aged 18 years and younger having any ovarian or tubal lesion resected at a comprehensive children's hospital between 2006 and 2021. Adnexa-sparing surgery was defined as preserving both the ovary and tube from which the lesion was resected. Postoperative ultrasounds were reviewed to document ovarian follicles, blood flow, volumes, and lesion recurrence.

RESULTS

Adnexal preservation was implemented in 168 of 328 pathological resections. MIS approach was used in 149 cases. Median age was 13.4 [11.0-15.3]. Among sparing surgeries, MIS associated with benign pathology, shorter operative time (median minutes: 78 MIS [59-111.5]; 130 open [92.8-149.8]; 174 MIS-to-open [132.8-199.5]; p = 0.010), and reduced hospital stay (median days: 1 MIS (Lindfors, 1971; Lovvorn III et al., 1998) [1-2]; 2 open [2-2.9], 2 MIS-to-open [1-3.3]; p = 0.001). Postoperative ovarian volume ipsilateral to the MIS procedure (median, 7.6 ml [4.3-12.1]) was relatively smaller than the contralateral ovary (median, 9.1 ml [5.5-15.0]). Blood flow was documented to the ovary in 70/94 (74.4%) of patients after MIS adnexal-sparing surgery. Distinct follicles were detected in 48/74 (64.8%) of post-menarchal patients after MIS adnexal-sparing surgery. Five ovarian cysts recurred.

CONCLUSIONS

MIS preserves adnexa reliably, with postoperative ovarian follicles and blood flow detected in most patients, and maintains ∼80% of contralateral volume, while achieving definitive tumor resection.

LEVEL OF EVIDENCE

III.

Apoptosis inhibition enhances induced pluripotent stem cell generation during T cell reprogramming

The widespread adoption of chimeric antigen receptor (CAR)-T cell therapy has been hindered by its complex and costly manufacturing process. Induced pluripotent stem cells (iPSCs) have shown promise as a cellular immunotherapy alternative, due to their unlimited self-renewal potential in culture and capacity to differentiate into functional immune cell types. However, it is imperative to carefully select the original cell for iPSC seed preparation, as iPSCs have been found to retain the epigenetic imprint of the original somatic cells. Additionally, the efficiency of reprogramming terminal differentiated cells for immunotherapy must be addressed. Our research highlights the superiority of lymphocyte-origin cells over embryonic stem cells in functional immune cell differentiation. Furthermore, blocking Fas-FasL induced apoptosis in T cells significantly improves iPSC generation. Interestingly, transient Fas suppression in T cells does not alter the expression of Fas in the resulting iPSCs or affect their differentiation potential. This finding brings up new avenues in the field of cellular immunotherapy and provides a solution for creating high-quality and suitable iPSCs for lymphocyte differentiation for immunotherapy purposes.

Risk of residual cancer after complete response following first-line chemotherapy in men with metastatic non-seminomatous germ cell tumour and International Germ Cell Cancer Cooperative Group intermediate/poor prognosis: A multi-institutional retrospective cohort study

INTRODUCTION

Current guidelines recommend surveillance in metastatic non-seminomatous germ cell tumour patients treated with first-line-chemotherapy and a complete clinical response (normalisation of serum tumour markers and residual masses <1 cm). However, this recommendation is based on a series including patients with good prognosis according to International Germ Cell Cancer Cooperative Group prognostic group (IGCCCG-PG). The aim of this study was to analyse the proportion of residual teratoma and survival among patients with intermediate/poor IGCCCG-PG and a complete clinical response after first-line-chemotherapy.

MATERIAL & METHODS

This is a retrospective study of men with intermediate/poor IGCCCG-PG, who had a complete clinical response after first-line chemotherapy. Patients were either followed by surveillance or treated with post-chemotherapy retroperitoneal lymph node dissection (pcRPLND).

RESULTS

Between 2009 and 2018, 143 men with intermediate (n = 83) or poor (n = 60) IGCCCG-PG were treated at 11 international centres. Among 33 patients treated with pcRPLND, the specimen showed teratoma and viable cancer in 16 (48%) and 4 (12%). During a median a 7-year follow-up, 20/110 (18%) patients managed with surveillance relapsed, of whom seven (6%) had a retroperitoneal-only relapse versus 2/33 patients managed with pcRPLND relapsed. No difference was observed regarding overall survival (OS) among men treated with pcRPLND or surveillance (5-year OS, 93% and 89%, p-value = 0.35). The median time-to-recurrence among men on surveillance was 1.3 years (range: 0.3-9.1), and the most common sites of relapses included retroperitoneum (11%), chest (5%), and bones (4%).

CONCLUSIONS

While most men with intermediate/poor IGCCCG-PG harbour teratoma/cancer in the retroperitoneum despite a complete response to first-line-chemotherapy, only 6% managed with surveillance relapsed in the retroperitoneum. There was no significant difference in OS between the two groups.

Reprint of: somatic-type malignancies in testicular germ cell tumors

The development of somatic-type malignancy (SM) in testicular germ cell tumor represents a major challenge in the diagnosis and treatment of testicular cancer. Most SMs are derived from teratoma, and the remainder is associated with yolk sac tumor. They occur more frequently in metastases than in primary testicular tumors. SMs demonstrate a variety of histologic types, including sarcoma, carcinoma, embryonic-type neuroectodermal tumor, nephroblastoma-like tumor, and hematologic malignancy. Sarcoma, particularly rhabdomyosarcoma, accounts for the majority of SMs in the primary testicular tumors, whereas carcinoma, particularly adenocarcinoma, is the most common SM in metastases. Although SMs derived from testicular germ cell tumors mimic their histologic counterparts in other organs with overlapping immunohistochemical profiles, isochromosome 12p is present in most SMs, which can be useful in the differential diagnosis. The presence of SM in the primary testicular tumor may not worsen the outcome, but the development of SM in metastasis is associated with a poor prognosis. Furthermore, somatic-type carcinoma is likely associated with a worse prognosis than somatic-type sarcoma. Although SMs respond poorly to the cisplatin-based chemotherapy, timely surgical resection is an effective treatment for most patients.

It Does Exist! Diagnosis and Management of Thyroid Carcinomas Originating in Struma Ovarii

Thyroid carcinoma originating in struma ovarii comprises a small minority of all cases of struma ovarii. Given the rarity of this diagnosis, literature to guide evaluation and management is limited. The most common carcinoma originating from struma ovarii is papillary thyroid carcinoma. Treatment includes surgery, including a fertility sparing approach if disease is confined to the ovary, with consideration of total thyroidectomy and radioactive iodine ablation for high-risk pathologic features or disease spread beyond the ovary. This review discusses the histopathologic findings, molecular pathology, clinical implications and management, and prognosis of thyroid carcinomas originating in struma ovarii.

Clinical characteristics and long-term management of prepubertal testicular teratomas: a retrospective, multicenter study

Prepubertal testicular teratomas are rare tumors with limited practical guidance for their management. This study aimed to analyze a large multicenter database to establish the optimal management of testicular teratomas. We retrospectively collected data on testicular teratomas in children younger than 12 years who underwent surgery without postoperative chemotherapy in three large professional children's institutions in China between 2007 and 2021. The biological behavior and long-term outcomes of testicular teratomas were analyzed. In total, 487 children (with 393 mature teratomas and 94 immature teratomas) were included. Among mature teratomas, 375 cases were testis-sparing, 18 were orchiectomies, 346 were operated through the scrotal approach, and 47 underwent the inguinal approach. The median follow-up period was 70 months, and no recurrence or testicular atrophy was observed. Among the children with immature teratomas, 54 underwent testis-sparing surgery, 40 underwent orchiectomy, 43 were operated through the scrotal approach, and 51 were operated through the inguinal approach. Two cases of immature teratomas with cryptorchidism had local recurrence or metastasis within 1 year of the operation. The median follow-up duration was 76 months. No other patients had recurrence, metastasis, or testicular atrophy.  Conclusion: Testicular-sparing surgery is the first treatment choice for prepubertal testicular teratomas, with the scrotal approach being a safe and well-tolerated strategy for these diseases. Additionally, patients with immature teratomas and cryptorchidism may have tumor recurrence or metastasis after surgery. Therefore, these patients should be closely followed up in the first year after surgery. What is Known: • There is a fundamental difference between testicular tumours in childhood and those in adulthood - not only in terms of the difference and incidence but also in terms of histology. • For surgical techniques, the inguinal approach is recommended for the treatment of testicular teratomas in children. What is New: • The scrotal approach being a safe and well-tolerated strategy for testicular teratomas in children. • Patients with immature teratomas and cryptorchidism may have tumor recurrence or metastasis after surgery. These patients should be closely followed up in the first year after surgery.

Histogenesis of intracranial germ cell tumors: primordial germ cell vs. embryonic stem cell

INTRODUCTION

Intracranial germ cell tumor (iGCT) is a rare disorder and often occurs during childhood and adolescence. iGCTs are frequently localized in pineal region and hypothalamic-neurohypophyseal axis (HNA). In spite of well-established clinical and pathological entity, histogenesis of iGCTs remains unsettled. Current theories of histogenesis of iGCTs include germ cell theory (from primordial germ cells (PGCs) of aberrant migration) and stem cell theory (transformed embryonic stem (ES) cells). In order to comprehend the histogenesis, we revisit the origin, migration, and fate of the human PGCs, and their transformation processes to iGCT.

DISCUSSION

In "germ cell theory," transformation of ectopic PGCs to iGCT is complex and involves multiple transcription factors. Germinoma is derived from ectopic PGCs and is considered a prototype of all GCTs. Non-germinomatous germ cell tumors (NGGCTs) develop from more differentiated counterparts of embryonic and extra-embryonic tissues. However, there is a distinct genomic/epigenomic landscape between germinoma and NGGCT. ES cells transformed from ectopic PGCs through molecular dysregulation or de-differentiation may become the source of iGCT. "Stem cell theory" is transformation of endogenous ES cells or primitive neural stem cell to iGCTs. It supports histological diversity of NGGCTs because of ES cell's pluripotency. However, neural stem cells are abundantly present along the subependymal zone; therefore, it does not explain why iGCTs almost exclusively occur in pineal and HNA locations. Also, the vast difference of methylation status between germinoma and NGGCT makes it difficult to theorize all iGCTs derive from the common cellular linage.

CONCLUSION

Transformation of PGCs to ES cells is the most logical mechanism for histogenesis of iGCT. However, its detail remains an enigma and needs further investigations.

Middle Ear Teratoma: Clinical and Imaging Features

BACKGROUND

Teratoma is a true neoplasm composed of a number of different types of tissue derived from the three germinal layers but rarely occurs in the middle ear (ME). The features of middle ear teratomas (MET) have not been well described.

OBJECTIVE

The objective of this study is to explore the clinical and imaging features of MET, and report 2 rare cases of MET with ear malformation that have never been reported.

MATERIALS AND METHODS

The clinical, CT and MRI data of 8 patients with a pathological diagnosis of MET were collected and retrospectively mined, and 14 patients with MET reported in previous literature were also reviewed.

RESULT

① Female, left ear predominance in MET, and the most common symptoms were otorrhea and hearing loss. ② On CT and MRI, the MET presented as an irregular soft tissue mass that was heterogeneous, with fatty tissue and involved multiple sites, and the ET and tympanum were correspondingly expanded and locally destroyed. ③ Mictotia with MET in two patients was presented, which was the first report.

CONCLUSION

MET has female sex and left ear predominance. CT and MRI can be used to diagnose MET and display its extent and its relationship to the carotid canal in detail. Complete surgical excision is the definitive treatment.

Eustachian Tube Teratoma: A Rare Entity

Introduction

Teratomas, tumors derived from all 3 fetal germ cell layers, are rarely located in the head and neck region and extremely rare in the Eustachian tube area.

Case report

The authors present the case of a 2 years old child with chronic ear discharge. Referral diagnosis was tumor or cyst of the temporal bone. Intraoperatively, a solid, hairy tumor located inside the Eustachain tube, with extension into the middle ear space was discovered and removed. Histology revealed a mature teratoma. Review of the literature showed reports of rare similar cases of Eustachian tube teratomas, differentiating themfrom hairy polyps of the rhynopharynx. The imaging of our patient, the surgical techique for removal of the tumor and long term follow-up are detailed.

Conclusions

Teratomas located inside the Eustachian tube are exceptional. Their removal should be carefully planned in view of their long term anatomical sequelae and in order to avoid long term postoperative morbidity.

Producing Engraftable Skeletal Myogenic Progenitors from Pluripotent Stem Cells via Teratoma Formation

Generating engraftable skeletal muscle progenitor cells is a promising cell therapy approach to treating degenerating muscle diseases. Pluripotent stem cell (PSC) is an ideal cell source for cell therapy because of its unlimited proliferative capability and potential to differentiate into multiple lineages. Approaches such as ectopic overexpression of myogenic transcription factors and growth factors-directed monolayer differentiation, while able to differentiate PSCs into the skeletal myogenic lineage in vitro, are limited in producing muscle cells that reliably engraft upon transplantation. Here we present a novel method to differentiate mouse PSCs into skeletal myogenic progenitors without genetic modification or monolayer culture. We make use of forming a teratoma, in which skeletal myogenic progenitors can be routinely obtained. We first inject mouse PSCs into the limb muscle of an immuno-compromised mouse. Within 3-4 weeks, α7-integrin+ VCAM-1+ skeletal myogenic progenitors are purified by fluorescent-activated cell sorting. We further transplant these teratoma-derived skeletal myogenic progenitors into dystrophin-deficient mice to assess engraftment efficiency. This teratoma formation strategy is capable of generating skeletal myogenic progenitors with high regenerative potency from PSCs without genetic modifications or growth factors supplementation.

Germ cell tumors of the central nervous system: A brief review and site-specific considerations

Germ cell tumors of the central nervous system (GCT-CNS) arise predominantly in midline locations of the CNS and affect young patients in their first to third decades of life. Involvement of the CNS is thought to be a sequelae of residual primordial germ cells with incomplete embryologic migration. Clinically, GCT-CNS present with symptoms of ventricular obstruction or compression of affected brain structures. Histologically, these tumors are analogous to their gonadal and extra-gonadal counterparts. Diagnosis relies heavily on morphology and immunohistochemical findings, and can be complicated by limited tumor sampling. There is currently only a limited role for molecular studies. Treatment of these lesions is made difficult by their involvement of deep and vital brain structures and accurate pathologic diagnosis is essential for appropriate therapy. Diagnosis should involve review of the clinical history, imaging studies, and assessment of serum and cerebrospinal fluid tumor markers. Current therapeutic strategies involving radiation therapy with or without chemotherapy are quite effective, in spite of the locational difficulties that often prevent gross total resection.

Fat-containing adnexal masses on MRI: solid tissue volume and fat distribution as a guide for O-RADS Score assignment

PURPOSE

To explore ways to improve O-RADS MRI scoring for fat-containing adnexal masses, by investigating methods for quantifying solid tissue volume and fat distribution and evaluating their associations with malignancy.

METHODS

This retrospective, single-center study included patients with fat-containing adnexal masses on MRI during 2008-2021. Two radiologists independently reviewed overall size (Sizeoverall), size of any solid tissue (Sizeanysolid), size of solid tissue that was not Rokitansky nodule (Sizenon-Rokitansky), and fat distribution. Wilcoxon test, Fisher-exact test, and ROC curve analysis were performed. Reference standard was pathology or follow-up > 24 months.

RESULTS

188 women (median age 35 years) with 163 benign and 25 malignant lesions were included. Sizeoverall (R1, 9.9 cm vs 5.9 cm; R2, 12.4 cm vs 6.0 cm), Sizeanysolid (R1, 5.1 cm vs 1.2 cm; R2, 3.2 cm vs 0.0 cm), Sizenon-Rokitansky (R1, 5.1 cm vs 0.0 cm; R2, 3.1 cm vs 0.0 cm), and fat distribution differed significantly between malignant and benign lesions (p < 0.01). Area under ROC curve was greatest using Sizenon-Rokitansky (R1, 0.83; R2, 0.86) vs Sizeoverall (R1, 0.78; R2, 0.81) or Sizeanysolid (R1, 0.79; R2, 0.81), though differences were non-significant (p = 0.48-0.93). Cutoffs for Sizenon-Rokitansky (R1, ≥ 1.2 cm; R2, ≥ 1.0 cm) yielded sensitivity and specificity of 0.72 and 0.93 (R1) and 0.76 and 0.95 (R2). Among immature teratomas, 85.7% displayed scattered fat.

CONCLUSION

Overall size, size of (any or non-Rokitansky-nodule) solid tissue, and fat distribution differed between benign and malignant fat-containing adnexal masses. Incorporating these would constitute simple and practical approaches to refining O-RADS MRI scoring.

Germ Cell Tumors of the Ovary: A Review

Ovarian germ cell tumors are a diverse group of benign and malignant neoplasms that occur in a wide age range, but with a predilection for younger age group. The majority are represented by the frequently encountered mature cystic teratomas. Malignant germ cell tumors are uncommon, and in some cases have a characteristic clinical presentation. However, from a histologic standpoint these tumors can sometimes be challenging to diagnose due to overlapping morphology with epithelial, and in some cases sex cord tumors. In these cases, a panel of immunohistochemical stains often facilitates the correct diagnosis. This review article discusses the clinicopathologic findings and pertinent ancillary studies of both common and uncommon germ cell tumors of the ovary.

Rib malignancies masquerading as benign mediastinal tumours

Mediastinal tumours are commonly encountered in general thoracic surgery practice. Benign tumours like thymoma and teratoma often need direct surgical resection if resectable. Pre-operative biopsy is not recommended. We report 2 cases which were radiologically diagnosed as thymoma and teratoma turned out to be Ewing sarcoma and chondrosarcoma respectively after surgical excision. This has challenged the notion whether biopsy is really not needed. More elaborate studies are needed to find out tumour characteristics which would warrant a biopsy even if they are resectable. In our cases, pre-operative biopsy would have changed the line of management in both patients. This has led to a change in institutional protocol that now, we do biopsy for any mediastinal tumour more than 8 cm and abutting the chest wall.

Alternative In Vivo Models to Study Teratoma

Embryonic stem cells give rise to teratomas when injected in vivo in experimental animal models. The characterization, the manipulation, and the breaking off of this specific characteristic are doubtlessly the last frontier for the applications of stem cells in translational medicine. Moreover, the urgency to adapt to new scientific demands drives the researcher to find alternative and faster models for testing the teratogenic properties of embryonic stem cells. Here, we compare the emerging model of the chick embryo chorioallantoic membrane (CAM) to the murine model, which represents the gold standard procedure for teratogenesis.

An unusual case of oropharyngeal mature teratoma in a kitten

Background

Extragonadal teratoma in the head and neck region is unusual in veterinary medicine. So far, only one case of oropharyngeal teratoma has been reported in a cat.

Case description

In this report, a 5-month-old kitten was brought to the clinic with the complaint of difficulty breathing, food intake, and oropharyngeal mass. In clinical examination, there was a large mass, protruding from the localization included left buccal mucosa, soft palate, and extending into the oropharynx but no cranial extension was observed in CT scans. The mass was completely resected. Macroscopically, the mass measured 4.5 × 6.5 cm2 and contained solid and cystic areas associated with soft and hard tissue components.

Findings/treatment and outcome

Histopathology revealed an extragonadal solid-cystic (grade 0) oropharyngeal mature teratoma containing structures from endoderm, mesoderm, and ectoderm. After an 8-month follow-up control period, no signs of recurrence were observed.

Conclusion

The case was deemed worthy of being presented with its clinical, radiological, and pathological findings, and complete resection was curative for mature teratoma.

Large Retroperitoneal Teratoma Presenting with Unilateral Hydronephrosis in an Infant: A Case Report and Review of the Literature

Teratoma is a type of germ cell tumor layer that appears in the gonadal, sacrococcygeal, mediastinal, and retroperitoneal regions. Primary retroperitoneal teratoma is rare and asymptomatic but can present with symptoms due to a mass effect on neighboring organs. These tumors have to be considered in the differential diagnosis of a mass in the abdominal cavity of children to distinguish between Wilms' tumor, neuroblastoma, and other intra-abdominal lesions. We presented an infant boy with protrusion of the left upper quadrant of the abdomen and a palpable abdominal mass that had progressively enlarged. An abdominal computed tomography scan revealed a large retroperitoneal cystic, solid mass on the left side of the abdominal cavity, causing pressure on the left ureter. Also, hydronephrosis of the left kidney was seen with a decreased enhancement of the left kidney due to obstruction uropathy. The mass was suspicious on imaging for a retroperitoneal teratoma. The patient underwent laparotomy, and excision of the huge retroperitoneal mass was done. The final diagnosis was an immature teratoma grade 3, and the patient was discharged in good condition. Retroperitoneal teratomas are rare tumors in infants. These tumors would be an incident diagnosis or diagnosed by the mass effect of giant tumors on other organs. They must be considered in the differential diagnosis of intra-abdominal tumors in children. Hydronephrosis and obstructive uropathy can be rare consequences of the mass effects of these tumors.

A neuroendocrine tumor within an anterior mediastinal mature teratoma: a case report

BACKGROUND

Mature teratomas are benign germ cell tumors. On rare occasions, they have been associated with somatic malignancies and are termed rare germ cell tumors with a somatic-type malignancy (GCTSM). Mature teratomas commonly comprise adenocarcinomas; only seven previous cases of mature teratomas with neuroendocrine tumors have been reported to date. Here, we report a patient with a neuroendocrine tumor whithin a mature teratoma.

CASE PRESENTATION

A 26-year-old man visited our department complaining of chest tightness. Contrast-enhanced computed tomography (CT) scans showed a strongly enhanced lesion within a 10-cm encapsulated cystic lesion in the anterior mediastinum. Positron emission tomography (PET) scans showed no areas of significant ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) accumulation. He underwent complete tumor resection via the transsternal approach. Histopathological examination of the specimen indicated a neuroendocrine tumor contained within a mature teratoma.

CONCLUSIONS

In this case, a neuroendocrine tumor was contained within a mature teratoma. Our patient had no specific symptoms and his serum markers were within the normal range. Although PET is beneficial for diagnosing other GCTSM, it is not useful in detecting a neuroendocrine tumor. Therefore, the preoperative diagnosis of neuroendocrine tumors contained within mature teratomas remains challenging. However, GCTSM should be suspected in patients exhibiting CT findings of a mediastinal tumor, measuring ≥ 6 cm, in addition to characteristic GCTSM findings. Moreover, surgery should be performed carefully in such cases.

Anesthesia for ovarian teratoma resection using remimazolam and remifentanil in a patient with anti-N-methyl-D-aspartate receptor encephalitis -two case reports

BACKGROUND

Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is a type of autoimmune encephalitis that causes characteristic symptoms through the formation of antibodies against NMDA receptors. If ovarian teratomas are detected, surgical removal under general anesthesia is often considered. Many general anesthetic agents inhibit NMDA receptors. As such, anesthetic agents may have unexpected effects on disease progression. For anesthesiologists, providing general anesthesia for these patients is challenging and there are few studies on which anesthetic is most appropriate.

CASE

Two female patients were diagnosed with anti-NMDA receptor encephalitis and ovarian teratomas. Successful teratoma resection was performed under general anesthesia using remimazolam and remifentanil. After the surgery, one patient showed some improvement but died a month later. The other patient progressively improved over time.

CONCLUSIONS

Remimazolam and remifentanil are useful general anesthetic agents for patients with anti-NMDA receptor encephalitis. Further studies are warranted.

[Current view on testicular tumors from a developmental biological perspective : Important biomarkers and molecular pathological investigations]

BACKGROUND

Germ cell tumors (GCTs) are the most common type of cancer in Germany in young men between 15 and 44 years of age. The routinely performed diagnostic procedures are essential for the patient's treatment, but can be difficult due to heterogenous histologies. Additionally, the molecular mechanisms of the development of the special forms growing teratoma syndrome (GTS) and testicular tumors with malignant somatic transformation (MST) as well as of therapy resistance are not fully understood.

OBJECTIVES

Updated understanding of the molecular processes underlying GCT development and their special forms as well as recommendations for new and useful biomarkers.

RESULTS

The development of GCTs is a dynamic process largely influenced by the microenvironment. Seminomas (SEs) in particular seem to posses a higher cellular plasticity than previously assumed, allowing SEs to be reprogrammed into an embryonal carcinoma (EC) or differentiate into extra-embryonal tissues (yolk sac tumors [YSTs], trophoblastic differentiation). Novel serological (mi371a-3p) and pathological (FOXA2) biomarkers are well suited to early detect GCTs and YSTs, respectively. For more aggressive tumors and special cases (GTS, MST), there are still no reliable diagnostics or specific/tailored therapies available.

CONCLUSION

The ability of SEs to transit into EC or YSTs should be considered during therapy. Future research should focus on deciphering the special forms GTS and MST as well as the early recognition of YSTs, since their development seems to be an escape mechanism to chemotherapy.