Germ cell tumors (GCT) are a complex, heterogeneous collection of tumors that may present in either gonadal or extragonadal sites. They consist of a variety of benign and malignant histologies that can occur at several locations throughout the body. An important component of treatment is surgical resection, and while the key components of resection are site specific, the universal goals of GCT resection include the complete resection of tumor without violating the tumor capsule, while preserving function of surrounding organs, minimizing morbidity, and assessing for regional spread.

Extragonadal germ cell tumors (EGCTs) are rare, representing <5% of all germ cell tumors (GCTs). Whilst EGCTs share morphological and immunohistochemical features with their gonadal counterparts, they tend to be more aggressive and are frequently associated with secondary somatic malignancies. The aim of our study was to evaluate the clinical, morphological and immunohistochemical features, and to analyze tumors for chromosomal abnormalities of 12p, in addition to any novel genetic alterations, in a series of EGCTs. Seventy-seven EGCTs were included. Anterior mediastinum was the most common anatomic site, followed by central nervous system, retroperitoneum, sacroccygeal area, and neck. Whole genome SNP array identified isochromosome 12p in 26% of tumors. Additional cytogenetic abnormalities included the presence of gain of chr 21 in 37% of tumors. Somatic-type malignancies were identified in 8% of patients. Disease progression (metastasis and/or recurrence) was documented in 8 patients, most of whom died from their relapse. Three patients who died of disease had somatic-type malignancies. Mediastinal seminomas had a significantly better overall survival when compared to mediastinal non-seminomatous GCTs. Our study demonstrates that EGCTs share similar histologic features, but diverse clinical outcomes compared to their gonadal counterparts. Outcomes vary according to anatomic location and histologic subtypes. Our data corroborate that somatic-type malignancies are frequently encountered in mediastinal EGCTs and that their presence portends a poorer prognosis.

BACKGROUND: The occurrence of extragonadal germ cell tumors (EGGCTs), either as primary tumors or metastatic disease, is rare. Forms of cytologic sampling, including fluid analysis, fine-needle aspiration, and/or small-core needle biopsy, have been shown to be reliable methods for the diagnosis of germ cell tumors. This study aims to investigate the utility of cytopathologic techniques in the diagnosis of EGGCTs at the authors\' institution.
METHODS: The laboratory information system was queried over a period of 10 years (2012-2022) to identify all cytology cases diagnosed on fluid cytology, FNA, and/or small-core biopsy as germ cell tumors in extragonadal locations. Patient demographics, tumor location, serum tumor marker levels, cytopathologic diagnosis, and follow-up surgical resection data were reviewed and correlated.
RESULTS: A total of 35 cases from 32 patients (all males) were identified. Thirty specimens contained satisfactory material for diagnosis (86%) and five were less than optimal for evaluation (14%). Despite this, all cases had clinically useful cytopathologic diagnoses. A total of 19 cytology cases (16 patients) had follow-up resection specimens available. Of these, 11 patients underwent preoperative chemotherapy. Nine patients showed no evidence of residual tumor and two showed histologic concordance. Of the five patients who did not have preoperative chemotherapy, all showed concordant histologic diagnoses.
CONCLUSIONS: Cytology can provide a reliable, accurate method for diagnosing EGGCTs. The practice of preoperative (neoadjuvant) chemotherapy places an extreme importance on the initial cytopathologic diagnosis because the majority of patients with follow-up resection in this series showed no residual tumor.

BACKGROUND: Extragonadal germ cell tumours (EGGCTs) originated in Shoulder are extremely rare, with 1 case described in the literature. We report a case of a patient with a primary Right Shoulder mixed EGGCT.
METHODS: A 36-year-old male patient was hospitalized for 6 months due to progressive right shoulder swelling accompanied by pain. Subsequently, the right shoulder tumor was removed entirely. Gross pathological examination showed that the size of the tumor mass was about 14 × 10 × 6 cm.Mutations were observed in ENPEP (4q25), ZCCHC11, RREB1 (6p24.3), CKAP4 (12q23.3), and other genes were detected by whole exome sequencing. Histology revealed a mixed EGGCT of the Right Shoulder with immature teratoma and yolk sac tumour. The patient went through 6 cycles of chemotherapy. After 7 months of follow-up, the patient is recurrence.
CONCLUSIONS: The primary MEGCT of the shoulder is an extremely rare condition. However, the recurrence and metastasis rates are high. Therefore, further research is necessary to determine this rare disease\'s genetic and clinical characteristics to develop an effective treatment plan.

UNASSIGNED: This study aimed to summarize the clinical features, treatment modalities, therapeutic effects, menstruation and fertility outcomes, and prognosis of extragonadal yolk sac tumors (YSTs) of the female genital tract.
UNASSIGNED: We reviewed 32 cases of extragonadal YSTs in the genital tract treated between 1983 and 2021. The medical records, including clinical characteristics, histopathology, treatments, chemo-reduced adverse events, and outcomes on long-term follow-up, were collected.
UNASSIGNED: Among the 32 cases, 30 were vaginal YSTs and two were uterine YSTs (endometrial and cervical). Thirty patients (30/32, 93.8%) were <4 years. Abnormal vaginal bleeding (n = 31) and elevated serum alpha-fetoprotein level (n = 32) were the most common presentations. Vaginohysteroscopy and/or pediatric rhinoscopy were used for diagnosis in 17 pediatric patients and evaluation of chemotherapeutic efficacy in 21 pediatric patients. All the patients received combination chemotherapy. Bleomycin/etoposide/cisplatin (BEP) was chosen with prior consideration in 28 cases; 21 patients were treated with BEP alone. Yellow or grayish-yellow tissue with irregular shape was found in 66.7% of the cases during repeat examinations. Five patients underwent surgeries during repeat examinations and follow-ups, and no evidence of malignancy was noted in them. Thirty-one patients achieved complete remission. During a median follow-up of 63 months (2.4-240.3 months), two patients experienced recurrence, three died, and 29 remained disease-free. One patient recovered menstruation and five had undergone menarche.
UNASSIGNED: BEP chemotherapy can serve as a preferred treatment modality for vaginal and uterine YSTs. Vaginohysteroscopy and pediatric rhinoscopy can be used for diagnosis and evaluation of chemotherapeutic efficacy in pediatric patients. YSTs possibly appear as yellow or grayish-yellow after chemotherapy.

Introduction Although nephroblastomas are frequently treated without prior biopsy, there are the occasional other pediatric renal tumors that require different management. In the literature, there are around 30 primary renal germ cell tumors (GCT), including four cases of Yolk sac tumor (YST). We present another primary renal YST.Case report: A five-year-old boy was diagnosed as Wilms tumor on radiology and needle biopsy. He received chemotherapy, with no response. The post-chemotherapy resection specimen revealed a YST.Conclusion: Renal YST may be indistinguishable from Wilms tumor clinically and radiologically. For pre-biopsy chemotherapy management protocols, serum tumor markers such as AFP may be recommended to identify the occasional GCT, including YST. Pre-chemotherapy needle biopsies may lead to misdiagnosis, and may require confirmation by an experienced pathologist or central review.

BACKGROUND: Duodenal teratoma is a rare condition with only four cases reported in the English literature. Radiological imaging and tissue sample are necessary for diagnosis in addition to tumor markers. The most effective treatment is still complete excision with safety margins.
METHODS: We report a case of 26 years-old-man, in whom epigastric pain, decreased appetite, and postprandial bilious vomiting had been prevalent for 5-6 months and had exacerbated prior to the emergency room. Enhanced abdominal computed tomography revealed a 10 × 15cm heterogeneous solid mass with cystic component in the third duodenum segment. The inferior veina cava and aorta were both compressed, although there was no sign of lymphadenopathy or ascites. An ulcerating non-bleeding lesion at the D2-D3 junction of the duodenum was discovered during a gastroduodenoscopy. Biopsies and immunohistochemical investigations revealed findings that were consistent with a mixed non-seminomatous germ cell tumor. A PET-CT scan was performed, which revealed FDG uptake by the duodenal lesion but no evidence of metastatic lesions. A distal duodenal segmentectomy is performed, and then a duodeno-jejunal anastomosis is used to restore continuity. The final diagnosis was teratomatous tumor of the duodenum without malignant changes.
CONCLUSIONS: This is the second adult case of main duodenal teratoma that has been reported. We publish it to encourage surgeons to think about this differential diagnosis and carefully plan surgery using a multidisciplinary approach.

Extragonadal germ cell tumors are uncommon in adults and only 2-5% of teratomas develop in extragonadal sites. Primary thyroid teratomas represent <0.1% of all primary thyroid gland neoplasms. In the present report, a case of primary thyroid teratoma in a 65-year-old female is described. Furthermore, the current literature regarding patients who were diagnosed with primary thyroid teratoma and underwent surgical resection was systematically reviewed. A total of 15 studies of 27 patients (age range, 17-65 years). Growing mass or neck swelling were the primary symptoms in 14 patients (51.8%). Only one (5.5%) patient was preoperatively diagnosed with malignant thyroid teratoma. All patients underwent thyroidectomy, but 6 cases had more advanced surgery, including lymph node dissection. A total of 12 patients received a combination of adjuvant chemoradiation postoperatively, 10 (45.4%) patients reported recurrence of disease and 8 (29.6%) were postoperatively diagnosed with distant metastases. A total of 9 (39.1%) patients died due to progression of the disease. In conclusion, primary thyroid teratomas are rare and difficult to diagnose preoperatively. In particular, malignant cases are very aggressive tumors with a considerably poor prognosis, even after surgical resection combined with adjuvant chemoradiation.

Juvenile granulosa cell tumor (JGCT) is the most common type of sex cord stromal tumor arising from gonadal structures of children and young adults. We present a 3.5-year-old girl with JGCT located in retroperitoneum without ovarian involvement. Extragonadal occurrences of other sex cord stromal tumors have been rarely reported, but this is the first case of JGCT in an extragonadal location. We speculate the possible underlying mechanism of sex cord stromal tumor formation in extragonadal locations. Furthermore, clinical presentation, differential diagnosis and management of this tumor in childhood are discussed.

Teratoma is a germ cell tumor (GCT) derived from stem cells of the early embryo and the germ line. Teratoma is the most common neoplasm of the ovaries and is usually diagnosed easily using imagings by detecting fat components. However, there are various histopathological types and the imaging findings differ according to the type. Teratoma usually occurs in the gonads or in the midline due to migration of primordial germ cells during development. The clinical course of teratomas depends on the age of the patient, histological type, and anatomical site. Sometimes teratomas show unusual manifestations, such as mature teratoma without demonstrable fat components, torsion, rupture, growing teratoma syndrome, anti-N-methyl-D-aspartate receptor encephalitis, and autoimmune hemolytic anemia. For all of these reasons, teratomas demonstrate a wide spectrum of imaging features and radiologists should be familiar with these variabilities. The present article aims to introduce a model encompassing types of GCTs based on their developmental potential, and to review several histopathological types in various anatomical sites and unusual manifestations of teratomas, with representative imaging findings.