Primary germ cell tumors of the mediastinum

Extragonadal Germ Cell Tumors: A Single Institution Experience with Clinicopathological Correlation

Background. Extragonadal germ cell tumors (EGCTs) are a rare heterogeneous group of tumors without evidence of primary gonadal germ cell tumors. They account for 2%-5% of overall malignancies. EGCTs are often not clinically suspected, making them challenging for pathologists. In this retrospective observational study, we describe our institutional experience among EGCTs with clinicopathological correlation. Materials and methods. All patients diagnosed as EGCTs from January 2014 to April 2023 were collected. All relevant clinical data and serum markers were retrieved from hospital medical records. Histopathology and immunohistochemistry slides were reviewed. Results. The present study included a total of 56 patients; 34 (60%) men and 22 (40%) women with a men-to-women ratio of 1.5:1. Of them, 1 patient had congenital/neonatal EGCTs, 21 patients had prepubertal EGCTs, and 34 had post-pubertal EGCTs. The common sites included are mediastinum (45%), sacrococcyx (18%), retroperitoneum (14%), and central nervous system (12%). The other rare sites were the vagina, liver, colon, and duodenum. The common germ cell tumor included mature teratoma (34%), mixed germ cell tumor (27%), seminoma/germinoma (12%), pure yolk sac tumor (11%), immature teratoma (9%), mature teratoma with somatic tumor (5%), and embryonal carcinoma (2%). All histological diagnoses of germ cell tumors were confirmed with IHC markers like PLAP, CD117 (KIT), AFP, LIN28, CD30, and β-hCG. Pre and posttreatment serum tumor marker levels were available in 37 patients. All our treated patients had a decrease or normal tumor marker levels post-therapy. Conclusion. In our study, a heterogeneous group of germ cell tumors was seen. Most of them were seen in post-pubertal adolescents and young adults. Early intervention by platinum-based combination chemotherapy in seminoma and nonseminomatous germ cell tumors has significantly improved the prognosis of malignant EGCTs similar to their germ cell counterparts.

Neuroendocrine Lesions Arising From Mediastinal Teratoma-A Case Report and Literature Review

Background. Neuroendocrine lesions arising from mediastinal teratomas are rare tumors with only small number of patients reported in literature. The behavior of these lesions appears to be different from traditional neuroendocrine neoplasms. A comprehensive review will be valuable for histologic assessment and treatment planning for similar cases. Case presentation. We present an example of a 57-year-old man who presented with cough. Subsequent work-up revealed an anterior mediastinal mass of 2.1 cm on computed tomography. The patient underwent robot-assisted thoracoscopic thymectomy. Histological examination revealed a mature cystic teratoma with a neuroendocrine component consisting of clusters of tumor cells with round to oval nuclei and a "salt-and-pepper" chromatin pattern. The tumor cells were immunoreactive to cytokeratin, synaptophysin, chromogranin, and INSM1, with a Ki-67 proliferative index of 4%. A histological diagnosis was mature teratoma with well-differentiated low-grade neuroendocrine tumor (carcinoid) was made. The patient was well and without disease after complete surgical excision at 10 months. Literature review. Literature reviewed yielded 13 examples of neuroendocrine lesions arising from mediastinal teratomas. No disease-related mortality was reported, even in lesions with high-grade neuroendocrine, carcinomatous, or immature teratomatous components. Conclusions. Surgical removal is the mainstay of treatment of these lesions, and the presence of a neuroendocrine component does not appear to negatively affect prognosis.

En bloc resection of an extremely giant mediastinal immature teratoma with somatic-type malignancy: A case report with a brief review of the literature

Primary mediastinum immature teratoma with somatic-type malignant transformation (SM) is extremely rare, and the clinical prognosis is poor. Immature teratoma with SM is difficult to eradicate by chemotherapy due to poor sensitivity; therefore, surgical resection is recommended whenever possible because it may offer better survival.

Primary germ cell tumours of the mediastinum: A review with emphasis on diagnostic challenges

This article will review current aspects of the histopathological, immunohistochemical and molecular analysis of primary mediastinal germ cell tumours (PMGCTs) as well as their aetiological, epidemiological, clinical and therapeutic features. PMGCTs represent an important differential diagnosis in the spectrum of mediastinal tumours, and their diagnosis is usually made on small tissue samples from core needle biopsies in combination with diagnostic imaging and serum tumour markers. As in lymphomas, a small biopsy is often the only viable tumour sample available from these patients, as they receive chemotherapy prior to eventual surgical resection. Pathologists therefore need to apply an efficient combination of immunohistochemical markers to confirm the diagnosis of a PMGCT and to exclude morphological mimics.

[18F]fluorodeoxyglucose positron emission tomography/computed tomography characteristics of primary mediastinal germ cell tumors

Primary mediastinal germ cell tumor (MGCT) is an uncommon tumor. Although it has histology similar to that of gonadal germ cell tumor (GCT), the prognosis for MGCT is generally worse than that for gonadal GCT. We performed visual assessment and quantitative analysis of [18F]fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG PET/CT) for MGCTs. A total of 35 MGCT patients (age = 33.1 ± 16.8 years, F:M = 16:19) who underwent preoperative PET/CT were retrospectively reviewed. The pathologic diagnosis of MGCTs identified 24 mature teratomas, 4 seminomas, 5 yolk sac tumors, and 2 mixed germ cell tumors. Visual assessment was performed by categorizing the uptake intensity, distribution, and contour of primary MGCTs. Quantitative parameters including the maximum standardized uptake value (SUVmax), tumor-to-background ratio (TBR), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and maximum diameter were compared between benign and malignant MGCTs. On visual assessment, the uptake intensity was the only significant parameter for differentiating between benign and malignant MGCTs (p = 0.040). In quantitative analysis, the SUVmax (p < 0.001), TBR (p < 0.001), MTV (p = 0.033), and TLG (p < 0.001) showed significantly higher values for malignant MGCTs compared with benign MGCTs. In receiver operating characteristic (ROC) curve analysis of these quantitative parameters, the SUVmax had the highest area under the curve (AUC) (AUC = 0.947, p < 0.001). Furthermore, the SUVmax could differentiate between seminomas and nonseminomatous germ cell tumors (p = 0.042) and reflect serum alpha fetoprotein (AFP) levels (p = 0.012). The visual uptake intensity and SUVmax on [18F]FDG PET/CT showed discriminative ability for benign and malignant MGCTs. Moreover, the SUVmax may associate with AFP levels.

A massive immature mediastinal teratoma treated with chemotherapy and surgical resection: a case report

BACKGROUND

Teratoma is a type of germ cell tumor consisting of one or multiple tissues derived from germinal layers. The location and size of the tumor can cause various presentations. Here we report one of the largest ever cases of immature cystic teratoma.

CASE PRESENTATION

In this report, we presented a 24-year-old patient with dyspnea, chest pain, nausea, and anorexia. A computed tomography scan revealed a giant, right-sided mass measuring about 190 × 150 × 140 mm. Chemotherapy was initiated for the patient, followed by thoracotomy. Histopathological evaluation revealed the nature of the mass to be an immature mediastinal teratoma.

CONCLUSION

the incidence of immature mediastinal teratoma is uncommon, and due to its rarity, the diagnosis needs more profound evaluation studies such as radiological and pathological assessments. Immature teratomas are optimally treated by a combination of chemotherapy and complete resection.

MRI Findings and Differential Diagnosis of Anterior Mediastinal Solid Tumors

The anterior mediastinum is the most common location of mediastinal tumors, and thymic epithelial tumors are the most common mediastinal tumors. It is important to differentiate thymic epithelial tumors from malignant lymphomas and malignant germ cell tumors because of the different treatment strategies. Dynamic contrast-enhanced MRI and diffusion-weighted imaging can provide additional information on the differential diagnosis. Chemical shift imaging can detect tiny fat tissues in the lesion and is useful in differentiating thymic hyperplasia from other solid tumors such as thymomas. MRI findings reflect histopathological features of mediastinal tumors, and a comprehensive evaluation of MRI sequences is important for estimation of the histopathological features of the tumor. In this manuscript, we describe the MRI findings of anterior mediastinal solid tumors and the role of MRI in the differential diagnosis.

Primary mediastinal yolk sac tumor: A case report and literature review

Key Clinical Message

There are limited published cases of primary mediastinal yolk sac tumor (PMYST), with no consensus on the best treatment alternative. By far, the surgery oriented comprehensive therapies are the main treatment methods. The surgical strategy should be individualized and aimed at radical resection, considering all the possibilities, including the use of cardiopulmonary bypass and prosthetic materials.

Abstract

A 15-year-old boy was diagnosed as PMYST. The tumor, with a size about 13 × 12 × 8 cm, was located in the right upper mediastinum, closely adhering to ascending aorta, superior vena cava, right atrium, and the right hilum. After 6 cycles chemotherapy of bleomycin, etoposide, and cisplatin (BEP), no significant change was found in the size of tumor. Subsequently, an extended tumor excision including partial resection of the right lung, the pericardium, the diaphragm and the right phrenic nerve, was performed successfully with cardiopulmonary bypass on standby. During 6 months of follow-up, there was no tumor recurrence. Meanwhile, in PubMed, we searched the English case reports and case series of PMYST during the past decade. A total of 73 articles were retrieved, in which 22 articles on the therapy and prognosis of PMYST were extracted and reviewed, included 16 case reports and 6 case series with a total of 52 patients. Due to the rarity of PMYST, it is difficult to provide a specific treatment regimen. The surgery-oriented comprehensive therapies are still the main treatment methods. The surgical strategy should be individualized and aim at radical resection, considering all the possibilities, including the use of cardiopulmonary bypass and prosthetic materials.

Genomic profiling of a metastatic anaplastic melanocytic neuroectodermal tumor arising from a mature thymic teratoma as part of a mediastinal germ cell tumor

Following chemotherapy, a mediastinal germ cell tumor can lead to a mature teratoma that is composed of tissues derived from all three germ layers. Although teratoma is usually curable, in rare cases it can give rise to various somatic tumors and exceptionally it undergoes melanocytic neuroectodermal tumor (MNT) transformation, a process that is not well-described. We report a patient with a postchemotherapy thymic teratoma associated with an MNT component who, 10 years later, additionally presented a vertebral metastasis corresponding to an anaplastic MNT. Using exome sequencing of the mature teratoma, the MNT and its metastatic vertebral anaplastic MNT components, we identified 19 somatic mutations shared by at least two components. Six mutations were common to all three components, and three of them were located in the known cancer-related genes KRAS (p.E63K), TP53 (p.P222X), and POLQ (p.S447P). Gene set enrichment analysis revealed that the melanoma tumorigenesis pathway was enriched in mutated genes including the four major driver genes KRAS, TP53, ERBB4, and KDR, indicating that these genes may be involved in the development of the anaplastic MNT transformation of the teratoma. To our knowledge, this is the first molecular study realized on MNT. Understanding the clinicopathological and molecular characteristics of these tumors is essential to better understand their development and to improve therapeutics.

Postoperative recurrence of mixed extragonadal germ cell tumor in the right shoulder: a case report

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.

CASE PRESENTATION

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.

CONCLUSION

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.

Primary Mediastinal Germ Cell Tumors: A Thorough Literature Review

Primary mediastinal germ cell tumors (PMGCTs) are a rare type of cancer affecting young adults. They have different molecular and clinical features compared to testicular germ cell tumors. Non-seminoma PMGCTs have the shortest 5-year overall survival and the poorest prognosis among all of the germ cell tumor presentations, while seminomas share the same survival and prognosis as their testicular counterparts. There is an unmet need for better treatment options for patients with non-seminoma PMGCTs in both first-line and salvage therapy, as the available options are associated with underwhelming outcomes. Identifying biological and genetic factors to predict treatment responses would be helpful in improving the survival of these patients.

Primary mediastinal germ cell tumors

Mediastinal germ cell tumors share similar histopathological, immunohistochemical, and molecular features with their counterparts in the gonads. Therefore, proper clinical and radiological evaluation of patients with an anterior mediastinal mass becomes essential in the final interpretation of these tumors. The gold standard for the diagnosis of these tumors remains histopathological evaluation. However, immunohistochemical stains and molecular studies also provide an aid in cases in which the histology is not typical. It is also important to keep in mind that a small mediastinoscopic biopsy may not be representative of the entire neoplasm. In this review, we will provide our perspective regarding histopathological diagnosis, staging, immunohistochemical and molecular profile, and briefly family of tumors address pertinent epidemiological, clinical and treatment options. However, the main emphasis is to review the process of pathological assessment in pre and post-treated tumors. Knowledge of the different growth patterns and histological associations is important, mainly when confronted with mediastinoscopic biopsies, which ultimately will determine treatment options.

A case of soft-tissue tumor over the sternum: A rare case report

The objective is to report a rare case of extragonadal seminoma over the manubrium sterni on the chest wall. A 42-year-old male patient, a chronic alcoholic for 10 years presented with a firm mass of approximate size 10 cm × 12 cm overlying the manubrium part of the sternum. A clinical diagnosis of soft-tissue tumor was made. All relevant preoperative workup was done. Fine-needle aspiration cytology of the mass was suggestive of serous cystic lesion with chronic inflammation. Wide local excision of the mass and primary closure of the wound was done, followed by histopathological examination. Unanticipatedly, on histology, the mass turned out to be extragonadal seminoma. Postoperative wound healing was satisfactory. Subsequently, the patient underwent adjuvant chemotherapy. Primary extragonadal seminoma itself is a rare tumor that affects mainly young people with mediastinum as the most commonly involved site and has higher chances of metastasis. This case of extragonadal seminoma (extragonadal germ cell tumour) over manubrium sterni without any mediastinal involvement in a patient in early forties presenting as soft-tissue tumor, itself is a rarer entity and perhaps one of the kinds. Hence, the case needs to be reported and further progression and prevention have to be discussed.

Atypical cartilage in type II germ cell tumors of the mediastinum show significantly different patterns of IDH1/2 mutations from conventional chondrosarcoma

Neoplastic cartilage is a common component of teratomas in type II germ cell tumors. Although IDH1/2 mutations have been well-described in somatic cartilaginous tumors, ranging from benign enchondromas to highly aggressive dedifferentiated chondrosarcomas, the presence of IDH1/2 mutations in cartilaginous neoplasms arising from germ cell tumors has not been previously investigated. To better understand the relationship between these tumors and their bone/soft tissue counterpart, we studied the IDH1/2 mutational status of 20 cases of primary mediastinal mixed germ cell tumors with areas of readily identifiable cartilaginous differentiation. Our study found that cartilaginous lesions arising in germ cell tumors have a different frequency and distribution of IDH1/2 mutations compared to those at somatic sites. We identified IDH1/2 mutations in only 15% (3/20) of cases, compared to a frequency in the literature among differentiated chondroid tumors of bone and soft tissue of 54%, a highly significant decreased frequency (p = 0.0011; chi-square test). Furthermore, they were exclusively IDH2 R172 mutations that occurred at a non-significant, increased frequency in the germ cell tumor group compared to conventional chondrosarcoma (15% vs. 5%, respectively, p > 0.05, chi-square test). The unexpected finding, therefore, was entirely attributable to the absence of IDH1 R132 mutation in chondroid neoplasia of germ cell origin (p < 0.00001, Fisher exact test). Our results suggest that a subset of cartilaginous lesions arising within type II germ cell tumors have a similar oncogenic mechanism to their bone/soft tissue counterpart but that the majority form using different oncogenic mechanisms compared to their somatic counterparts.

Unilocular thymic cyst with features of intra-thymic bronchogenic cyst: A clinicopathological correlation of 4 cases

Four cases of primary unilocular thymic with features of bronchogenic cyst are presented. The patients are three men and a woman between the ages of 43 and 57 years. All the patients presented with symptoms of cough, chest pain, and dyspnea. Diagnostic imaging revealed the presence of an anterior mediastinal cystic lesion. Initial mediastinoscopic biopsies were non-diagnostic. Surgical resection of the anterior mediastinal cystic lesion was performed in all patients. Macroscopically, all the lesions were described as large cystic lesions measuring from 2 to 4 cm in largest diameter and containing yellowish fluid. The surface of the cysts was described as corrugated and of brownish color. The walls of the cysts were not thickened and no other elements were described. Histologically, the cystic lesions were characterized by single cystic structures lined by ciliated epithelium. No atypia or mitotic activity was present in any of the cases. Immunohistochemical stains show positive staining of the respiratory epithelium with keratin and negative staining for GATA3, PAX-8, TTF-1, and Napsin. All the patients have recovered well after surgical resection.

Spindle cell thymoma (WHO type A) - Choriocarcinoma: An unusual association: A clinicopathological and immunohistochemical study of 3 cases

Three cases of an unusual association between spindle cell thymoma (WHO type A) and choriocarcinoma are presented. The patients are three men between the ages of 58 and 68 years. Clinically, all the patients presented with non-specific symptoms of cough, dyspnea, and chest pain. Clinical history and physical examination did not reveal the presence of any prior malignancy. Diagnostic imaging showed in the three patients the presence of a large anterior mediastinal mass. A core needle biopsy was obtained in the three patients. In two patients the biopsy showed the classic histology of a spindle cell thymoma while in one patient the biopsy showed the association of two tumors - spindle cell thymoma and choriocarcinoma. Surgical resection via thoracotomy was performed in the three patients. The mediastinal tumors measured between 9 and 17 cm in greatest diameter and were described as solid and lobulated with areas of hemorrhage. Histologically, all the tumors showed similar histological features of spindle cell thymoma (WHO type A) associated with a high-grade neoplasm composed of round and multinucleated giant cells compatible with choriocarcinoma. Immunohistochemical stains showed positive staining for keratin 5/6, and p40 in the spindle cell component, while the choriocarcinomatous component showed positive staining for human chorionic gonadotropin and human placental lactogen. The cases herein presented highlight not only the unusual association of spindle cell thymoma and choriocarcinoma but also raises some issues regarding the histogenesis of germ cell tumors, in this case choriocarcinoma.

Surgical management of primary mediastinal mature teratoma: A single-center 20 years’ experience

Background

This study aims to investigate the clinical efficacy of video-assisted thoracic surgery (VATS) in treating mediastinal mature teratoma (MMT) and explore the clinical factors that increase the difficulties associated with VATS.

Method

We retrospectively reviewed 101 consecutive patients with MMT who underwent surgical excision between November 2001 and June 2021. Follow-up was done by telephone or at an outpatient clinic. The deadline for follow-up was February 2022.

Results

The operative time, the chest tube indwelling time, and the hospital stay duration were significantly shorter in the VATS group compared with the thoracotomy group. The intraoperative and postoperative complication rates in the VATS group were lower than that of the thoracotomy group (P &lt; .05). In thoracoscopic surgery, the clinical symptoms during the course of the disease were significantly associated with bleeding loss increasing [odds ratio (OR) = 3.562; 95% confidence interval (CI) 1.180–10.753, P = .024] and operation time extension (OR = 5.697; 95% CI 1.529–21.221, P = .010). The relationship between lesions and superior vena cava or innominate vein from preoperative CT imaging was significantly associated with bleeding loss increasing (OR = 4.629; 95% CI 1.463–14.639, P = .009). A maximal lesion diameter greater than 7 cm was significantly associated with increased risks of operation time extension (OR = 5.019; 95% CI 1.641–15.348, P = .005).

Conclusion

Compared with traditional thoracotomy surgery, VATS can be performed safely in selected patients with MMT. A surgical method for complete resection needs to be determined according to preoperative imaging and intraoperative conditions to reduce the unnecessary damage.

Primary immature teratoma of the thigh: a review

Teratomas are a subtype of germ cell tumors composed of a variety of somatic tissues derived from more than one of the three germinal layers (ectoderm, endoderm and mesoderm). They can be classified as mature tumors and immature tumors. Teratomas most commonly arise at the sacrococcygeal region and the gonads. The occurrence of a teratoma outside the common gonadal and midline locations is exceptional. This review article lists the reported primary and metastatic malignant teratomas in extragonadal locations and discusses the possible explanation for the atypical location, their treatment and prognosis.

Standard versus high-dose chemotherapy in mediastinal germ cell tumors: a narrative review

OBJECTIVE

The aim of this review is to analyze feasibility and toxicities of high-dose chemotherapy (HDCT) in comparison to standard dose chemotherapy (SDCT) in patients affected by mediastinal germ cell tumors (MGCTs), discussing factors that may affect therapeutic choices, such as: management of residual disease, early response predictors for chemotherapeutic efficacy and determinants of chemotherapeutic resistance. In this review, we discuss the main clinical experiences with HDCT and SDCT in germ cell tumor (GCT) patients specifically in those affected by MGCT.

BACKGROUND

MGCTs represent a very small subset characterized by a poor prognosis, despite improvements in their clinical management and in understanding their biology. From early 1970s, HDCT has become an alternative to SDCT for both first-line and salvage therapeutic settings in advanced GCT patients. Several HDCT schedules-either cisplatin or carboplatin-based-have been tested so far, both in clinical randomized trial and in single-center experiences, with divergent results in terms of clinical outcomes and tolerability. Moreover, the majority of these studies included, but were not exclusively designed for, advanced MGCT patients, making difficult to infer data for this specific subset.

METHODS

an extended review of literature through PubMed was conducted using the keywords "mediastinal germinal cell tumors", "standard dose chemotherapy" and "high dose chemotherapy".

CONCLUSIONS

HDCT regimens could not be considered to date a standard option as first-line therapy in advanced MGCT patients, whilst they could be an alternative to SDCT regimens in relapsed tumors after proper patient selection.

[Mediastinal Tumors]

If mediastinal tumours cause symptoms these are related to their anatomical localization or a paraneoplastic syndrome. The differential diagnosis is based on the clinical situation with finding the lesion, and, furthermore, taking into account the age and sex of the patient, and the mediastinal compartment where the lesion is located. Cross-sectional radiographic diagnostic is essential for defining the therapeutic strategy. The anterior mediastinum is dominated by thymic tumours, mediastinal lymphomas, germ cell tumours and ectopic mediastinal poiters. The middle mediastinal compartment is the most frequent place of mediastinal cystic tumours, whereas the posterior mediastinum is the domain of neurogenic tumours. For selected cases a tissue biopsy is required. Surgery is the mainstay for most mediastinal tumours. Median sternotomy is the most frequent conventional surgical technique while minimally invasive surgery with thoracoscopic and above all robot assisted operation techniques are increasingly frequent. Combined chemotherapy and modern radiotherapy are essential components of the comprehensive treatment for mediastinal tumours.

How to classify, diagnose, treat and follow-up extragonadal germ cell tumors? A systematic review of available evidence

PURPOSE

To present the current evidence and the development of studies in recent years on the management of extragonadal germ cell tumors (EGCT).

METHODS

A systematic literature search was conducted in Medline and the Cochrane Library. Studies within the search period (January 2010 to February 2021) that addressed the classification, diagnosis, prognosis, treatment, and follow-up of extragonadal tumors were included. Risk of bias was assessed and relevant data were extracted in evidence tables.

RESULTS

The systematic search identified nine studies. Germ cell tumors (GCT) arise predominantly from within the testis, but about 5% of the tumors are primarily located extragonadal. EGCT are localized primarily mediastinal or retroperitoneal in the midline of the body. EGCT patients are classified according to the IGCCCG classification. Consecutively, all mediastinal non-seminomatous EGCT patients belong to the "poor prognosis" group. In contrast mediastinal seminoma and both retroperitoneal seminoma and non-seminoma patients seem to have a similar prognosis as patients with gonadal GCTs and metastasis at theses respective sites. The standard chemotherapy regimen for patients with a EGCT consists of 3-4 cycles (good vs intermediate prognosis) of bleomycin, etoposid, cisplatin (BEP); however, due to their very poor prognosis patients with non-seminomatous mediastinal GCT should receive a dose-intensified or high-dose chemotherapy approach upfront on an individual basis and should thus be referred to expert centers Ifosfamide may be exchanged for bleomycin in cases of additional pulmonary metastasis due to subsequently planned resections. In general patients with non-seminomatous EGCT, residual tumor resection (RTR) should be performed after chemotherapy.

CONCLUSION

In general, non-seminomatous EGCT have a poorer prognosis compared to testicular GCT, while seminomatous EGGCT seem to have a similar prognosis to patients with metastatic testicular seminoma. The current insights on EGCT are limited, since all data are mainly based on case series and studies with small patient numbers and non-comparative studies. In general, systemic treatment should be performed like in testicular metastatic GCTs but upfront dose intensification of chemotherapy should be considered for mediastinal non-seminoma patients. Thus, EGCT should be referred to interdisciplinary centers with utmost experience in the treatment of germ cell tumors.

Mediastinal Teratoma: A Pictorial Essay

종격동은 생식선 이외에서 발생하는 기형종의 가장 호발하는 부위로 알려져 있다. 종격동 성숙 기형종은 주로 젊은 성인에서 나타나고 남녀 간 발생 빈도의 큰 차이 없이 나타난다. 종격동 기형종은 대부분 전종격동에서 관찰되고, 일반적으로 증상을 보이지 않지만 종괴의 크기가 크거나 파열이 발생할 경우 여러 합병증이 나타날 수 있다. 종격동 기형종은 대부분 조직 검사 없이 전산화단층촬영(CT)만으로 진단될 수 있다. 하지만 파열된 기형종 혹은 악성 기형종의 경우 임상적 그리고 영상의학적으로 비전형적인 양상을 보여 진단이 어려울 수 있다. 본 종설에서는 종격동 기형종의 다양한 발현 양상을 영상 검사 소견을 중심으로 살펴보고자 한다.

Outcomes After Multidisciplinary Management of Primary Mediastinal Germ Cell Tumors

OBJECTIVE

We examined management strategies, overall survival (OS), and progression-free survival (PFS) among patients with PMNSGCTs undergoing resection and multidisciplinary management at a high-volume institution.

SUMMARY OF BACKGROUND DATA

Outcomes after resection of PMNSGCTs are not well-characterized, with limited data on factors associated with survival.

METHODS

We reviewed patients with PMNSGCT who underwent resection between 1980 and 2019. Median follow-up was 3.4 years. Preoperative therapy (including use of bleomycin), surgical management, recurrence, and survival were examined. Factors associated with survival were analyzed using Cox regression.

RESULTS

In total, 113 patients were included [median age, 28 years (range, 16-65)]. Preoperative serum tumor markers (STMs) normalized/decreased in 74% of patients. Pathology included necrosis only (25%), teratoma +/- necrosis (20%), viable nonteratomatous germ cell tumor +/- teratoma (41%), and secondary somatic-type malignancy +/- teratoma (20%). Bleomycin chemotherapy was not associated with pulmonary complications or 90-day mortality. Patients receiving second-line chemotherapy followed by resection had significantly worse OS and PFS than patients receiving first-line chemotherapy followed by resection. On multivariable analysis, R1/R2 resection (HR, 3.92; P < 0.001) and increasing postoperative STMs (HR, 4.98; P < 0.001) were associated with shorter PFS; necrosis on pathology (HR, 0.42, P = 0.043) was associated with longer PFS.

CONCLUSIONS

In patients with PMNSGCT undergoing resection, completeness of resection, postoperative pathology, and postoperative STMs were associated with PFS. Induction bleomycin was not associated with pulmonary complications or mortality in patients undergoing resection. Patients undergoing second-line chemotherapy followed by resection have a poor prognosis, with long-term survival of 22%.

Primary Mediastinal Nonseminomas: A Population-Based Surveillance, Epidemiology, and End Results Analysis

BACKGROUND

This study aimed to determine the disease characteristics and prognosis of patients with primary mediastinal nonseminomas (PMNS) in a Surveillance, Epidemiology, and End Results (SEER) analysis.

MATERIALS AND METHODS

Demographic, treatment, and survival outcome data of cases with PMNS from 1975 to 2016 were retrieved. Cases with unknown variables mentioned in the analysis were excluded. Relative statistical methods were applied to analyze clinical characteristics and prognosis.

RESULTS

A total of 587 PMNS patients met the selection criteria, 526 of whom were men. The mean age of patients was 28 (1-85) y. A total of 511 PMNS patients had validated subtypes, including 172 mixed germ cell tumors, 117 yolk sac tumors, 111 malignant teratomas, 70 choriocarcinomas, and 41 embryonal carcinomas. Patients with yolk sac tumors had the highest 3-y cancer-specific survival (CSS) rate (66.9%), while those with choriocarcinoma and embryonal carcinoma showed the worst prognosis. Surgery + chemotherapy (46.2%) was the most common and effective treatment for each subtype of PMNS. Multivariate Cox proportional hazards analysis identified embryonal carcinoma, malignant teratoma, choriocarcinoma, tumor size >15 cm, nodal metastasis, and distant stage as risk factors. In contrast, surgery-based care and younger age were protective factors. Propensity score matching analysis revealed significant improvement in the 5-y CSS rate from 35.8% to 60.3% with surgery (P < 0.001). However, radiotherapy (P = 0.436) and chemotherapy (P = 0.978) showed no survival benefits.

CONCLUSIONS

10 percent of the PMNS patients were female. Choriocarcinomas and embryonal carcinomas had the worst prognosis. Surgery was demonstrated to be the only way to prolong survival time. Chemotherapy and radiotherapy had minimal effects on prognosis.

Large mediastinal germ cell tumor with disease progression during systemic therapy

A 29-year-old male developed acute onset severe shortness of breath and fevers and was found to have a 17 cm anterior mediastinal mass with immature teratoma and possible mixed germ cell tumor on biopsy. He remained hospitalized during neoadjuvant cisplatin-based chemotherapy due to compressive symptoms from his mass and neutropenic fevers. Despite 3 cycles of therapy, his tumor mildly increased in size. After multidisciplinary discussion, he underwent urgent en bloc resection with a right hemi-clamshell incision. His postoperative course was uncomplicated and he was discharged to home within a week. His final pathology demonstrated mixed germ cell tumor.

Primary mediastinal germ cell tumours: an immunohistochemical and molecular diagnostic approach

AIMS

Primary mediastinal germ cell tumours (PMGCTs) are rare mediastinal neoplasms and their diagnosis can be challenging due to small biopsy samples. The aim of this study was to elaborate a diagnostic algorithm using immunohistochemical stainings with focus on novel markers and molecular analysis of isochromosome 12p [i(12p)].

METHODS AND RESULTS

Paraffin-embedded tissues of 32 mediastinal tumours were analysed using immunohistochemical stainings for SALL4, LIN28, OCT3/4, D2-40, CD117, SOX17, SOX2, CD30, ß-hCG, GATA3, FOXA2, GPC3, AFP, TdT, NUT and pan-cytokeratin. Quantitative real-time polymerase chain reaction (qPCR) was performed to investigate i(12p) status. Fifteen seminomas, seven teratomas, one yolk sac tumour, one choriocarcinoma and seven mixed PMGCT were diagnosed. Each entity had different immunohistochemical staining patterns which helped to distinguish them: seminoma (OCT3/4, D2-40, CD117, TdT), embryonal carcinoma (OCT3/4, SOX2), yolk sac tumour (FOXA2, GPC3, AFP) and choriocarcinoma (ß-hCG, GATA3). Mature teratomas stained positive for pan-cytokeratin in epithelial components and focally for SALL4, SOX2, GATA3, D2-40 and FOXA2. Furthermore, a NUT carcinoma mimicking a PMGCT was diagnosed showing a strong nuclear SOX2 and speckled nuclear NUT staining. i(12p) was detected in 24 out of 27 PMGCTs [89%].

CONCLUSION

A diagnostic algorithm is of great importance for a reliable diagnosis of PMGCTs in the usually small tissue biopsy samples. Therefore, a combination of three to four antibodies to identify the correct histological subtype is usually necessary in addition to morphological features. The i(12p) status serves as an additional option to underline germ cell origin in selected cases.

The diagnostic and prognostic value of tumor markers in giant mediastinal endodermal sinus tumor with prolonged survival: Twelve-year follow up after radical resection

We report a case of 16 -year male who presented with nonproductive cough, chest pain, and hemoptysis. His chest -x-ray and computerized tomographic scan (CT) of the thorax with contrast enhancement revealed a large mediastinal mass mostly occupying the left hemithorax. Percutaneous CT scan-guided biopsy of the mediastinal mass was reported as an endodermal sinus tumor (EDST). Serum alpha-fetoprotein levels were markedly raised (120,000 ng/ml). After completion of chemotherapy repeat, CT scan of the thorax revealed a large residual mass. Radical resection of the tumor was carried out. Twelve-year post-surgical resection follow-up with serial serum alpha-fetoprotein (AFP) tumor marker levels and CT scan of the thorax showed no recurrence.

Thymoma: Challenges and Pitfalls in Biopsy Interpretation

The interpretation of biopsy specimens in the diagnosis of thymoma is a subject that is generally not addressed in the literature. Even though the diagnosis of thymoma may seem to be an easy step in the assessment of these tumors, in reality, it is the biopsy specimen interpretation that will be use to determine course of action in any particular patient. It may determine whether a patient is a surgical candidate or on the contrary whether a patient may be benefited the most by medical therapy. In addition, there may be conditions in which all that is required is surgical resection without any further treatment, and that the evaluation of those conditions does not necessarily required the careful pathologic staging that thymomas need. In addition, it is important to highlight that in small biopsies, there are limitations not only in terms of the cellularity and other features that may not be present in such biopsy but also the limitation in term of immunohistochemical interpretation. Herein we have attempted to highlight numerous tumoral conditions that are frequently encountered in the daily practice of mediastinal pathology, some of them pose significant problems in separating them from thymomas. Needles to say, the entire spectrum of mediastinal pathology that may at any given time mimic thymoma is well beyond the scope of this review. Furthermore, we also herein emphasize the need for proper clinical and radiologic information and correlation in order to lead to a better interpretation of the biopsy specimen. The emphasis in this review is on thymoma and their possible pitfall and shortcomings while evaluating small biopsy specimens.

Mediastinal Germ Cell Tumors: A Review and Update on Pathologic, Clinical, and Molecular Features

Mediastinal germ cell tumors (MGCTs) are the most common extragonadal germ cell tumors (GCTs) and most often arise in the anterior mediastinum with a male predilection. MGCTs also have a predilection for patients with Klinefelter syndrome and possibly other genetic conditions. MGCTs, as GCTs at other extragonadal sites, are thought to arise from germ cells improperly retained during migration along the midline during embryogenesis. Similar to their counterparts in the testes, MGCTs are classified into seminomatous and nonseminomatous GCTs. Seminomatous MGCT represents pure seminoma, whereas nonseminomatous MGCTs encompass pure yolk sac tumors, embryonal carcinoma, choriocarcinoma, mature or immature teratoma, and mixed GCTs with any combination of GCT types, including seminoma. Somatic-type or hematologic malignancies can also occur in association with a primary MGCT. MGCTs share molecular findings with GCTs at other sites, most commonly the presence of chromosome 12p gains and isochromosome i(12p). Treatment includes neoadjuvant chemotherapy followed by surgical resection of residual tumor, with the exception of benign teratomas, which require only surgical resection without chemotherapy. In this review, we highlight and provide an update on pathologic, clinical, and molecular features of MGCTs. Immunohistochemical profiles of each tumor type, as well as differential diagnostic considerations, are discussed.

Coexistence of the BRCA1 and KRAS mutations in a patient with salivary gland carcinoma arising in mediastinal mature teratoma

Teratoma with malignant transformation is a rare type of malignant teratoma. In the present case, we describe a patient with salivary gland carcinoma (SGC) generating in mediastinal mature teratoma. Next-generation sequencing showed BRCA1 and KRAS somatic mutations, which might be associated with malignant transformation of the mediastinal mature teratomas. To our knowledge, the present case is the first report of coexistence of BRCA1 and KRAS mutations in mature cystic teratoma with malignant transformation to SGC. And the tumor showed a good response to chemotherapy with cisplatin and paclitaxel according to the transformed histology.

Primary mediastinal germ cell tumours with high prevalence of somatic malignancy: An experience from a single tertiary care oncology centre

BACKGROUND

Primary mediastinal germ tumours (PMGCT) constitute, a mere 3-4% of all germ cell tumours (GCT). Although they account for approximately 16% of mediastinal tumours in adults and 19-25% in children as per western literature, there is hardly any large series on PMGCT reported from the Indian subcontinent.

DESIGN

We have retrospectively analysed clinicopathological features of 98 cases of PMGCT diagnosed over 10 years (2010-2019) from a tertiary-care oncology centre.

RESULTS

The study group (n = 98) comprised predominantly of males (n = 92) (M:F ratio-15:1), with an age range between 3 months to 57 years (median: 25 years). The tumours were predominantly located in the anterior mediastinum (n = 96). Broadly, Non-seminomatous germ cell tumours (NSGCT) were more common (n = 73, 74%) compared to pure seminoma (n = 25, 26%). Mixed NSGCT was the most common histological subtype (n = 30) followed by pure mature teratoma (n = 18), pure Yolk sac tumour (n = 13), mixed seminoma and NSGCT (n = 5), pure immature teratoma (n = 3) and GCT; NOS (n = 4). Interestingly, all female patients had exclusive teratomas. Nine cases revealed secondary somatic malignancy (5 carcinomas and 4 sarcomas). The majority of patients received neoadjuvant chemotherapy (n = 71). Surgical excision was performed in 60 patients. Follow up was available in 68 patients. NSGCT showed a poor prognosis as compared to seminoma (p value = 0.03) and tumours with somatic malignancies had a more aggressive clinical course.

CONCLUSION

PMGCT was seen predominantly in young adult males and somatic malignancies were noted in as high as 9% of cases. Patient with somatic malignancy have aggressive clinical course, hence, extensive sampling and careful histopathological evaluation are recommended for the identification and definitive characterization.

Vasculogenic Mesenchymal Tumor: A Clinicopathologic and Molecular Study of 55 Cases of a Distinctive Neoplasm Originating From Mediastinal Yolk Sac Tumor and an Occasional Precursor to Angiosarcoma

We report 55 postchemotherapy resections of primary nonseminomatous mediastinal germ cell tumors with prominent vasculogenic features showing the formation of rudimentary to well-developed neoplastic vessels within primitive mesenchyme. These cases represented 25% of a cohort of 221 such specimens. The patients were 19 to 49 years old (mean, 28 y) and 98% had serological evidence of yolk sac tumor. The vasculogenic lesions, felt to represent a neoplastic reiteration of embryonic vasculogenesis in the splanchnic mesoderm of the yolk sac, were further subdivided into teratoma with vasculogenic stroma (n=9), vasculogenic mesenchymal tumor (VMT) (n=42, further classified into low grade [n=24] and high grade [n=18]), and angiosarcoma (n=4). The distinction of teratoma with vasculogenic stroma from VMT was based solely on the greater extent of VMT (exceeding 1 low power [×4 objective] microscopic field), with both categories showing a spectrum of vessels lined by atypical endothelium in a nonendothelial neoplastic stroma that often also generated vascular walls comprised of atypical smooth muscle. The angiosarcomas showed stratification of highly atypical endothelial cells or anastomosing vessels lined by nonstratified but cytologically similar endothelium. Immunohistochemical studies supported the generation of neoplastic vessels from the tumor stroma, most commonly by the development of stromal clefts showing reactivity for podoplanin, CD34, and occasionally ERG, followed by the gradual development from the clefts of thin-walled vessels that later became encircled by stromal cells showing smooth muscle differentiation by immunohistochemistry. Occasionally, round collections of stromal erythrocytes became surrounded by stromal cells to generate blood vessels. Fluorescence in situ hybridization showed chromosome 12p copy number increase in both the endothelial component and stromal component in 8/9 VMT cases and in 1/1 angiosarcoma. On follow-up, no patient with teratoma with vasculogenic stroma had evidence of a subsequent vascular tumor or sarcoma, whereas 8 of the 35 (23%) patients with VMTs (2 low grade and 6 high grade) and meaningful follow-up developed sarcoma (1 angiosarcoma, 2 rhabdomyosarcomas, and 5 not further characterized). The difference between low-grade and high-grade tumors was of borderline significance (P=0.058). Two of the 4 patients with angiosarcoma died of metastatic angiosarcoma, with the other 2 disease-free at 6.8 and 7 years. Compared with the 165 patients with follow-up and no vasculogenic lesions, there was a highly significant (P=4.3×10-5) association of any vasculogenic lesion with sarcomatoid tumors during the clinical course of VMT patients. In addition, 5/46 patients with follow-up and vasculogenic lesions (11%) died of either leukemia or myelodysplastic syndrome compared with 2 of 166 (1%) lacking them (P=0.0012). Three of the 5 patients had identifiable immature hematopoietic cells within their vasculogenic lesions, but 4 other VMT patients with these did not develop leukemia or myelodysplasia. We conclude: (1) vasculogenic lesions are frequent in postchemotherapy resections of primary mediastinal germ cell tumors with yolk sac tumor components; (2) they mostly consist of neoplastic vessels in a stroma that also generates neoplastic vascular walls of smooth muscle; (3) VMTs are associated with an increased incidence of sarcomas, even though most vasculogenic lesions in this context do not meet criteria for angiosarcoma; (4) the presence of vasculogenic lesions in postchemotherapy resections of primary mediastinal germ cell tumors place patients at increased risk for leukemia or myelodysplasia.

Ruptured mediastinal mature teratoma causing severe mediastinitis: report of a surgically resected case and a literature review

Background

Mediastinal teratomas occasionally rupture into the thoracic cavity, which induces mediastinitis or various other severe complications. Surgical treatment is crucial for ruptured teratomas; however, few literature reviews to date have addressed the characteristics of ruptured mediastinal teratomas.

Case presentation

We report a 29-year-old woman with severe mediastinitis owing to a mediastinal mature teratoma that ruptured into the mediastinum and right pleural cavity. Surgical resection by median sternotomy was performed within 24 hours after emergency admission. Intraoperative findings demonstrated the ruptured wall of the tumor with exposure of its white contents, which appeared similar to skin and fat, and necrotic tissue in the anterior mediastinum. The tumor was adhered to the right upper lobe, the ascending aorta, and pericardium. Owing to the severe adhesion of the tumor caused by inflammation in the surrounding tissues, a small portion of the tumor could not be removed, and hence complete resection with a sufficient surgical margin was not achieved. Pathologically, the tumor consisted of a solid mass and a cystic mass with severe adhesion to the resected portion of the lung, which included skin and lipid tissue. The tumor was concluded to be a mature teratoma as neither an immature component nor malignant transformation was observed. The patient had an uneventful postoperative course.

Conclusions

To our knowledge, this is the report of successful surgical resection of a ruptured mediastinal teratoma causing severe mediastinitis, with the first literature review of ruptured mediastinal teratomas. We also discuss relevant findings from reports in the literature.

Multimodality treatment outcome in patients with primary malignant mediastinal germ cell tumor in adults

BACKGROUND

Malignant mediastinal germ cell tumor (MGCT) is rare and has poor outcomes even after multimodality treatment. Data from resource-poor countries are scarce in the literature.

AIMS

To evaluate the clinicopathologic features and treatment outcome of primary malignant MGCT at our center.

METHODS AND RESULTS

Single institutional data review of patients aged ≥18 years, treated with a diagnosis of malignant MGCT between Nov'2013 and Nov'2019. Risk stratification was done as per International Germ Cell Cancer Collaborative Group (IGCCCG) classification. Patients were treated with platinum based chemotherapy and surgical resection for the residual disease was performed in non-seminomatous histology.28 patients had MGCT with a median age of 25 years (range:18-36) and all were male. Seven patients had superior vena cava obstruction (SVCO) at diagnosis and pre-treatment histological diagnosis was available in 23 (82%) patients. Seven (25%) patients had seminoma histology, all were of good risk as per IGCCCG risk criteria, whereas others had non-seminoma histology with poor-risk group. Seven patients with seminoma histology achieved a complete response after initial treatment. Six patients with non-seminoma histology underwent complete resection of residual disease post-chemotherapy and five revealed residual viable tumors. After a median follow-up of 10.8 months (range:2.9-75), 3-year progression-free survival (PFS) and overall survival (OS) estimate was 61.2% and 94.7% in the whole cohort, respectively and 3-year PFS and OS estimate was 100% in patients with seminoma histology.

CONCLUSIONS

This is the largest data set of MGCT patients' outcomes reported from India with multi-modality treatment. All patients were male and one-fourth had SVCO at presentation. Seminoma histology patients had a 100% outcome after initial platinum based chemotherapy. But, those with non-seminoma histology had a poor outcome even with chemotherapy and surgery.

Primary mediastinal germ cell tumors: Survival outcomes and prognostic factors - 10 years experience from a tertiary care institute

Primary Mediastinal Germ Cell Tumor (PMGCT) is a rare and heterogeneous entity. These tumors are typically diagnosed in young adults and carry a poor prognosis. We conducted this study to evaluate the role of radiotherapy on treatment outcomes and prognostic factors in PMGCT that may allow a more adapted treatment strategy to improve survival. Case records of patients who presented with PMGCT over a period of 10-years from January-2009 to December-2019 were retrospectively evaluated. Survival analyses were calculated using Kaplan-Meier (Log-rank) method. Poor prognostic factors for survival were evaluated with Multivariate analysis using Cox-regression method. A total of 46-patients data was analyzed, the majority of the patients were males (95.7%) with a median age of 25-years (range, 17–62). Non-seminomatous histology was predominant (60.9%). Sixteen-patients (34.7%) presented with complications at their initial presentation. Majority of the patients were treated with multimodality approach using chemotherapy, surgery, and/or radiotherapy. At a median follow-up of 40.8 months, the 1, 3, and 5-year overall survival (OS) was 69.6%, 52.2%, and 44.7% respectively. Patients who received radiotherapy in first-line treatment showed significant improvement in 5-year OS (72% vs 30%, p = 0.004) and disease-free survival (70% vs 24%, p = 0.007) in comparison with patients who did not receive. Multivariate analysis revealed that radiotherapy, chemotherapy, surgery, and complications at presentation were independent prognostic factors for OS. PMGCTs are aggressive neoplasms especially in patients presenting with disease-related complications. Dual modality management (radiotherapy as local therapy along with chemotherapy) had shown improvement in survival.

Immature Teratoma of the Palm: A Rare Site of Presentation

Extragonadal teratomas in adults are an extremely rare entity. Teratomas may be mature or immature and are characterized by their midline presentation. We are presenting here a case report of immature teratoma of the palm in a 35-year-old female. The patient developed a recurrent swelling of the palm from which a wedge biopsy was taken and sent for histopathological examination. A diagnosis of "immature teratoma, grade 2" was made, whose margins were compromised. Later on ultrasonography (USG) abdomen and pelvis and whole-body magnetic resonance imaging (MRI) showed no significant findings ruling out the possibility of an occult primary. MRI palm showed a well-defined cystic lesion with loculations suggestive of teratoma. Re-exploration was advised to achieve free margins.

Mediastinal Masses: 18F-FDG-PET/CT Features Based on the International Thymic Malignancy Interest Group Classification

Imaging plays a key role in the management of mediastinal masses. In an effort to standardize the analysis of the mediastinum, the International Thymic Malignancy Interest Group (ITMIG) has proposed a three compartments-based diagnostic classification, intended for clinicians and radiologists. Several articles have documented its usefulness to guide the diagnosis using cross-sectional imaging. Similarly, fluorine-18-radiolabeled fluorodeoxyglucose positron emission tomography combined to computed tomography (¹⁸F-FDG-PET/CT) can be useful in this setting, either as a first-line diagnostic technique, or in addition to cross-sectional imaging. In this article, which is thought as an aid for nuclear medicine physicians and radiologists, we aim to present, based on the ITMIG classification, the main mediastinal pathologies that can be observed with ¹⁸F-FDG-PET/CT, and the additional diagnostic value that can be expected from this technique. For this purpose, we segmented the mediastinum according to the ITMIG classification, and reviewed the available literature for each of the corresponding organs and/or disease. Given the importance of the clinical context for the interpretation of PET imaging, we presented each of the diseases according to: (1) their suggestive clinical context; (2) the suggestive features on nonenhanced CT (which is the standard in PET imaging); and (3) the typical ¹⁸F-FDG characteristics. The purpose of this article is to depict the main features of the most common mediastinal diseases that can be encountered with ¹⁸F-FDG-PET/CT, and to highlight its diagnostic value in this setting, alone or in combination with other imaging modalities.

Sub-centimeter adenocarcinoma arising from mature mediastinal teratoma during 11 years of follow-up

A 54-year-old male presented with exertional dyspnea, right massive pleural effusion, and an anterior mediastinal tumor (6.5 × 6.2 × 7.6 cm) which continued to grow during the 11-year follow-up period. Fluorodeoxyglucose positron emission tomography demonstrated a focal but remarkable uptake within the tumor mass. After chest tube drainage, the patient underwent surgical resection via a right thoracotomy. The final pathology was determined to be a mature cystic teratoma with malignant transformation to adenocarcinoma. Teratomas with somatic-type malignancy are challenging to diagnose using only preoperative evaluations. Intra-operative findings, histopathological findings, and postoperative management techniques are discussed in this report and emphasize the importance of early resection for treatment of mature teratomas, as well as the recommendation of careful inspection of pathological specimens of long-standing teratomas.

Germ Cell Tumor with Bronchial Fistula

Germ cell tumors account for 15% of anterior mediastinum tumors. Fistulas are abnormal communications between two surfaces covered by the epithelium. A fistula can occur between the bronchial tree and the adjacent anatomical structures secondary to variable etiologies. The main clinical manifestations of bronchial fistulas include hemoptysis, purulent cough, and pneumonia, which might threaten the patient's life. Diagnosis can be established with computed tomography, which shows direct and indirect signs of a fistulous tract. We present the case of a 25-year-old patient, with an embryonic carcinoma of the mediastinum, who developed a fistula between the mediastinal mass and the bronchial tree after chemotherapy and thoracic radiotherapy. We carried out a review of the literature about the epidemiological aspects and the physiopathology and the relevant radiological findings of this pathology.

Thoracoscopic surgery approach to mediastinal mature teratomas: a single-center experience

Background

Mediastinal mature teratomas are rare tumors with diverse surgical approaches. The aim of this study is to review our experience of thoracoscopic surgery management in patients with teratomas.

Methods

We retrospectively reviewed 28 consecutive patients with mediastinal mature teratomas who underwent thoracoscopic surgery at Viet Duc University Hospital from January 2008 to August2018. Patients were divided into 2 groups with 2 types of thoracoscopic surgery, closed thoracoscopic surgery (CTS) group and video-assisted thoracoscopic surgery (VATS) group. The selection of sugical approach was based on sizes, locations and characteristics of tumors. Post-operative outcomes were assessed and compared between these 2 groups.

Results

There were 14 female and 14 male patients with a median age of 41.2 ± 13.8 years. A total of 22 teratomas were located on the right side of the chest cavity and 6 on the left side. We performed CTS in 21 patients (75%) and VATS in 7 patients (25%) for tumor resection. There were 3 cases (10.7%) required conversion to minithoracotomy (5 cm in incision length). Skin appendages accounted for the highest rate (96.4%) in pathology. There was no record of mortality or tumor recurrence detected by computerized tomography.

Conclusion

A thoracoscopic surgery for a mediastinal mature teratoma was a feasible choice. Challenging factors such as large tumors, intraoperative bleeding and strong tumor cell adhesion were considered handling by conversion to mini-thoracotomy that could ensure safety procedures and complete removal of tumors. Extraction of tumor contents might be performed for patients with large mature cystic teratomas to facilitate thoracoscopic surgery.

Neutrophil-to-lymphocyte ratio in primary mediastinal germ cell tumors: A retrospective analysis of >20 years single institution experience

OBJECTIVES

To obtain information on outcome stratified by histology, extent and primary treatment patients' data with primary malignant mediastinal germ cell tumors treated between 1998 and 2018 were retrospectively analyzed.

METHODS

The primary treatment for localized malignant mediastinal germ cell tumors was neoadjuvant bleomycin + etoposid + cisplatin (BEP) ± surgery (n = 22); or surgery ± adjuvant BEP (n = 16). For disseminated disease (n = 21) first line BEP ± second line chemotherapy were administered. For nonseminomas (NS) the NLR at start of BEP was analyzed in relation to disease-free survival (DFS), progression-free survival (PFS), and overall survival (OS).

RESULTS

After neoadjuvant treatment the 5-year DFS was 100% for seminomas (S), and 63.4% for NS. The 5-year OS was 100% for S, and 76.9% for NS. The 5-year DFS and OS after surgery ± BEP for S was 72.9% and 100%, for NS was 75% and 87.5%, respectively. The 5-year PFS and OS of metastatic patients for S was 60% and 80%, while the median PFS and OS of NS were 5.7 and 11.1 months, respectively. Objective response (P = 0.006) and low NLR (P = 0.043) were independent prognostic markers of longer OS.

CONCLUSIONS

We confirmed the good outcome of BEP-treated S, while NS had poorer prognosis. Previously published prognostic models for NS were validated. Based on NLR and response a new prognostic model was developed.

Mixed-type primary germ cell tumor of the mediastinum in a young adult male with a sudden life threatening condition: A case report

Primary germ cell tumors of the mediastinum are rare neoplasms. Above all, choriocarcinomas are highly aggressive with early haematogenous dissemination. Here, we report an extremely rare case of mixed‐type primary germ cell tumor of the mediastinum which occurred in a 26‐year‐old man with multiple metastases of the lung caused by choriocarcinoma components, with diffuse pulmonary hemorrhaging. The patient developed a sudden life threatening condition a few days after a needle biopsy.

Key points

Significant findings of the study: This was an extremely rare case of mixed‐type germ cell tumor in a young adult male who developed a sudden life threatening condition due to choriocarcinoma components just a few days after a needle biopsy.

What this study adds: Serious conditions may occur in patients with germ cell tumor containing choriocarcinoma components. At present, there is no other way to treat such patients than to promptly recognize complications and perform urgent multimodal intervention.

Extragonadal germ cell tumors: Not just a matter of location. A review about clinical, molecular and pathological features

Extragonadal germ cell tumors (EGGCTs) are uncommon neoplasms, which arise in anatomical locations other than gonads. The pathogenesis of these neoplasms is still poorly understood and it is a matter of debate if they really represent extragondal primary neoplasms or rather extragondal metastasis from occult gonadal neoplasms. The actual observations suggest that EGGCTs represent a unique entity, so their biology and behavior are substantially different from gonadal counterparts. The diagnosis of EGGCTs is often challenging, and differential diagnosis is particularly wide. Nevertheless, a correct diagnosis is essential for the correct management of the patient. We summarize the state of art about EGGCTs, with particular emphasis on diagnosis and prognosis.

Primary Mediastinal Choriocarcinoma in an Elderly Patient with Concurrent Goserelin-Treated Prostate Adenocarcinoma

Mediastinal pure choriocarcinomas are exceedingly rare representations of germ cell tumours and are associated with a poor prognosis. To date, fewer than 20 cases have been reported. This current report describes an elderly patient who developed a large rapidly growing mediastinal tumour. Unfortunately, the patient expired before a definitive diagnosis could be reached. An autopsy revealed that the histomorphological features of the tumour showed two distinct tumour cell populations (syncytio- and cytotrophoblasts), and the diagnosis of choriocarcinoma was made. Immunohistochemical analysis showed a characteristic staining pattern in agreement with published studies. Here, we report a case of primary mediastinal choriocarcinoma in an elderly male with concurrent metastasizing prostate adenocarcinoma treated with long-term goserelin deposits, which, as we speculate, could have induced the choriocarcinoma.

Pediatric mediastinal germ cell tumors

Mediastinal germ cell tumors (GCTs) are a rare and heterogeneous group of neoplasms. Although histologically resembling their gonadal counterparts, they differ considerably in their clinical characteristics, biological behavior and prognostic outcome. The rarity of mediastinal GCTs has hindered their meaningful analysis, with most studies and clinical trials including them along with other extragonadal GCTs, which has led to a lack of consensus on optimal treatment strategies, and a lull in improvement in patient outcomes. Diagnosis of mediastinal GCT requires a multipronged approach, and encompasses multidisciplinary treatment including chemotherapy followed by surgery, with or without radiotherapy. In view of sustained response rates to current management protocols, the focus needs to be shifted to identifying patients in whom treatment regimens can be downscaled with the aim of decreasing long term morbidity and improving quality of life in low risk patient groups, while improving survival rates in poor risk patient subsets. In this scenario, better understanding of the molecular pathogenesis of these tumors may lead to identification of novel biomarkers and therapeutic targets, as well as improved disease segmentation and risk stratification, thus helping to avoid the toxicity and morbidity associated with current one-fits-all treatment strategies. Multi-institutional collaborations across continents are necessary to generate meaningful data, and are the face of future developments in this arena.