Primary malignant mediastinal germ cell tumors: A single institutional experience

Current Trends in the Surgical Management of Yolk Sac Tumors

Mediastinal yolk sac tumors (YST) constitute a highly malignant subtype of primary non-seminomatous germ cell tumors, which are often locally advanced and unresectable at diagnosis. Due to their rarity and aggressiveness, there is not yet a standard optimal treatment approach. A widely employed multimodal strategy involves neoadjuvant cisplatin-based combination chemotherapy followed by consolidation surgery. Tumor infiltration into the lungs and adjacent cardiovascular structures is common, such that surgical intervention typically requires extensive resections, performed either by sternotomy or thoracotomy. For this review, we extensively searched the PubMed and Embase medical databases, identifying articles describing surgical treatment of mediastinal yolk sac tumors. The current literature provides limited details regarding the utilized surgical procedures, leaving clinicians without comprehensive guidance about the demanding nature of these resections. Here, we present a narrative description of the range of current surgical procedures. By highlighting these techniques, we provide a comprehensive overview of the current surgical landscape, thereby helping clinicians understand the potential complexities and considerations involved in managing these rare and aggressive tumors.

Survival difference among adult and pediatric mediastinal yolk sac tumors cases: A meta-analysis of case reports

BACKGROUND

Mediastinal Yolk sac tumors (YST) are rare and highly malignant extragonadal germ cell tumors with rapid growth and early metastases. We sought to conduct a meta-analysis of published case reports/case series to compare differences in survival, demographics, and treatment modalities between adult and pediatric patients with YST.

METHODS

Ovid Embase, Cochrane, and Ovid Medline databases were searched for primary mediastinal pure YST cases. The primary outcome was overall survival (OS). Log-rank and Cox regression were used. This study is registered on PROSPERO (CRD42022367586).

RESULTS

Among 846 studies, 87 met our inclusion criteria including 130 patients (Adults: 90 and Pediatrics: 40). About 41.5% of the patients were from the United States. The median age was 23.0 (Q1-Q3: 17.0-30.0), 88.5% were males, and (32.3%) were Asian. Stage II represented almost 40%. AFP was elevated in 96.9%. Respiratory distress was the presenting symptom in 65.4%. Chemotherapy, radiotherapy, and surgery were utilized in 84.6, 23.1, and 64.7% respectively. Median OS was 24 months (Adults: 23 months, Pediatrics: 25 months, P = 0.89). 3- and 5-year OS were 34.4% and 22.9% in adults and 41.5% and 41.5% in pediatrics, respectively. On multivariate analysis, anterior location of tumors, receipt of chemotherapy, and undergoing surgery were associated with better OS.

CONCLUSION

Primary mediastinal YSTs are rare, but lethal neoplasms. Our meta-analysis showed that mediastinal YSTs mimic other non-seminomatous mediastinal GCTs in terms of clinical characteristics and available treatment options. Early diagnosis, neoadjuvant chemotherapy, and surgical resection are the key points for effective management and improved outcomes.

[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.

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.

A Challenging Case of Heart Displacement by a Large Mediastinal Germ Cell Tumor

Mediastinal germ cell tumors (GCTs) are rare and aggressive cancers originating from the germ cells in the mediastinum. Early detection and treatment are vital due to their high potential for metastasis and recurrence. We present a case of a 28-year-old man who exhibited a cough and shortness of breath. Laboratory tests revealed elevated tumor markers, alpha-fetoprotein, and beta-human chorionic gonadotropin. Imaging studies displayed a large mediastinal mass, causing the right displacement of the mediastinum and cardiac tamponade. The biopsy confirmed a non-seminomatous GCT, specifically a yolk sac tumor. The patient experienced pericardial effusion and cardiac tamponade after receiving two cycles of etoposide and cisplatin chemotherapy. To relieve the tamponade, an emergency pericardiocentesis was performed malignant GCTs necessitate prompt diagnosis and treatment and utilizing multimodal therapy such as chemotherapy to achieve tumor control. Due to the high risk of metastasis, vigilant surveillance for recurrence is essential, emphasizing the need for specific criteria for accurate early detection.

Dramatic response to local radiotherapy in a refractory metastatic mediastinal yolk sac tumor patient harboring a germline BRCA2 frameshift mutation: a case report

Mediastinal yolk sac tumors (YSTs) are highly aggressive germ cell tumors with an extremely poor prognosis. Radiotherapy plays an important role in the treatment of mediastinal YSTs. To maximize benefit from radiotherapy in patients with mediastinal YSTs, exploring functionally relevant biomarkers is essential. Previous studies have demonstrated that mutations in DNA-damage repair (DDR) genes, including BRCA1/2, potentially enhance sensitivity to radiotherapy in solid tumors. However, DDR-gene mutations, as possible predictive biomarkers for radiotherapy in primary mediastinal YSTs, have not yet been reported. Herein, we report a 29-year-old male patient with a refractory metastatic primary YST involving a germline frameshift mutation in the BRCA2 gene (NM_000059.3: exon11: c.4563_4564delAT: L1522fs). During treatment alternation, the patient was found to respond poorly to chemotherapy with or without an immune checkpoint inhibitor but well to radiotherapy. Finally, the patient achieved approximately 17 months of overall survival. To the best of our knowledge, this case report is the first to describe a remarkable response to local radiotherapy in a patient with a refractory metastatic mediastinal YST involving a DDR-gene mutation (germline BRCA2 frameshift variation). This case report provides insightful clues for precision radiotherapy in clinical practice.

Anterior Mediastinal Benign Teratodermoid Tumour With Intraparenchymal Extension Through Cystobronchial Connection: A Rare Case Report

Asymptomatic presentation is common in benign mature mediastinal tumours. Symptoms of the above diseases are sometimes life-threatening and can cause massive hemoptysis, recurrent pulmonary infection, hypoxia related to the pulmonary parenchymal hemorrhage, or pressure effect on or more of the major bronchi. A 16-year-old boy presented with frequent episodes of hemoptysis and recurrent fever unresponsive to antimicrobials. On investigation, it was found to be a benign mature mediastinal mass with cystobronchial connection to the right middle lobe. Resection of this mass resulted in the complete recovery of the individual. An anterior mediastinal benign teratodermoid tumour with intraparenchymal extension through cystobronchial connection is very rare. Surgical resection is challenging but offers the complete cure.

Primary Mediastinal and Testicular Germ Cell Tumors in Adolescents and Adults: A Comparison of Genomic Alterations and Clinical Implications

Simple Summary

The germ cell tumors (GCTs) family is a heterogeneous group of neoplasms that includes tumors affecting testis (TGCTs) and rarer cases occurring in extragonadal sites. Mediastinal germ cell tumors (MGCTs) are more aggressive and have poorer prognosis. Due to their rarity of MGCTs, few molecular and clinical studies are reported. MGCTs share biological similarities with TGCT, and international guidelines recommend use of the same therapies validated for TGCT. However, while high response rate is achieved in TGCT, MGCT tend to be resistant to therapy. This review resumes all molecular findings reported in MGCTs, summarizing molecular characteristics common with TGCT and highlighting the different molecular alterations that characterize mediastinal tumors. A deeper understanding of the MGCT biology will help in clinical management of these patients.

Abstract

Mediastinal germ cell tumors (MGCTs) share histologic, molecular and biomarkers features with testicular GCTs; however, nonseminomatous MGCTs are usually more aggressive and have poorer prognosis than nonseminomatous TGCTs. Most nonseminomatous MGCT cases show early resistance to platinum-based therapies and seldom have been associated with the onset of one or more concomitant somatic malignancies, in particular myeloid neoplasms with recent findings supporting a common, shared genetic precursor with the primary MGCT. Genomic, transcriptomic and epigenetic features of testicular GCTs have been extensively studied, allowing for the understanding of GCT development and transformation of seminomatous and nonseminomatous histologies. However, MGCTs are still lacking proper multi-omics analysis and only few data are reported in the literature. Understanding of the mechanism involved in the development, in the progression and in their higher resistance to common therapies is still poorly understood. With this review, we aim to collect all molecular findings reported in this rare disease, resuming the similarities and disparities with the gonadal counterparts.

The clinical features and prognostic outcomes of primary mediastinal yolk sac tumors: A retrospective analysis of 15 rare cases from multiple centers

Primary mediastinal yolk sac tumors (PMYSTs) are a rare occurrence. As such, the clinicopathological features, treatment, and prognosis, of this disease still remain unclear. In this study, we aimed to provide further information relating to this rare malignancy in order to facilitate the creation of more specific clinical guidelines for the diagnosis and treatment of patients with PMYSTs.In this retrospective study, we recruited 15 patients who had been diagnosed with PMYST from four medical institutions to create a population-based cohort. We then used Kaplan-Meier analysis and the log-rank test to investigate and compare overall survival (OS) and progression-free survival (PFS).A total of 15 cases were identified. The mean age was 27.3 years (range: 19-34 years). The estimated 1- and 2-year PFS rates were 66.7% and 60.0%, respectively. The 1- and 2-year OS rates were both 73.3%. Computer tomography scans revealed tumors were located in the anterior middle mediastinum (5 cases), the anterior superior mediastinum (1 case), the left anterior mediastinum (3 cases), and the right anterior mediastinum (6 cases). Of the 15 patients receiving extended resections, the majority (40.0%) underwent tumor resection, partial pericardiotomy, pulmonary wedge resection, and mediastinal lymphadenectomy. R0 resections were achieved in eleven patients. Four patients underwent R2 resection and experienced postoperative complications, including pneumonia (2 cases), atelectasis (1 case), and bronchopleural fistula (1 case). Four patients developed postoperative lung metastasis. Three patients died due to progressive diseases. Disease recurred in all patients at a median of 8.0 months (range: 6.0-11.0 months).PMYST is a rare but highly malignant tumor with a poor prognosis. Tumor resection, with optimal extended surgical management, may provide patients with the best chance of a cure although postoperative complications relating to the pulmonary systems should be treated with caution.

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.

Primary mediastinal germ cell tumours: real world experience in the low middle income (LMIC) setting

PURPOSE

Primary mediastinal germ cell tumours (PMGCTs) are rare; with limited data available about their outcomes and optimal treatment in the low middle income countries setting. We studied the clinical profile of patients with PMGCT treated at our centre in order to estimate their survival outcomes and to identify prognostic factors affecting the same.

PATIENTS AND METHODS

Fifty-seven patients with PMGCTs treated between April 2001 and June 2019 were included. Baseline characteristics, details of first line chemotherapy, response rates, toxicity and surgical outcomes were noted. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method.

RESULTS

Among 57 male patients (seminoma = 20 and nonseminomatous = 37), the median follow-up was 10 months (range: 1-120 months). For mediastinal seminoma, 9 (45%) and 11 (55%) patients had good and intermediate risk disease, respectively. Nineteen patients (95%) received BEP (Bleomycin, etoposide and cisplatin) chemotherapy. 94.7% had partial responses and median event-free survival was not reached. All patients were alive and disease free at 2 years. For primary mediastinal nonseminomatous germ cell tumours (PMNSGCTs), all patients were poor risk. Thirty-four (91.8%) received BEP/EP chemotherapy as first line. Responses were PRM+ (partial response with elevated markers) in 7 (20.5%) and PRM- in 12 (35.2%). The incidence of febrile neutropenia was 50% and 55.8% in seminole and PMNSGCT, respectively. The median OS was 9.06 months and median PFS was 4.63 months for PMNSGCT. The proportion of patients alive at 1 year and 2 years were 35% and 24.3%, respectively.

CONCLUSION

Primary mediastinal seminomas are rarer and have better survival outcomes. Treatment of PMNSGCT is still a challenge and is associated with poorer survival outcomes.

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 yolk sac tumor: a case report and literature review

Primary mediastinal yolk sac tumors (YSTs) are rare and have a high degree of malignancy. This article reports a 42-year-old man with a primary mediastinal YST. The patient presented with chest tightness and shortness of breath. Using a contrast-enhanced computer tomography (CT) scan, the mediastinal space was found to be occupied by a mass shadow, about 10 cm × 8 cm with a clear boundary and low density. Serum alpha-fetoprotein (AFP) was elevated to 7169.66 ng/ml. The 5th day after hospitalization, a percutaneous biopsy of the mediastinal mass was performed. Malignant tumor cells were found by cytologic examination. According to the pathological morphology and immunohistochemical results, the tumor was diagnosed as primary mediastinal YST. Subsequently, the patient underwent five cycles of adjuvant chemotherapy including bleomycin, etoposide, and cisplatin (BEP) and surgical tumor removal. One month after operation, AFP was elevated to 252.96 ng/ml. CT examination showed that the tumor recurred. As of September 12, 2020, the patient has undergone four cycles of VIP (etoposide, ifosfamide, cisplatin) chemotherapy after relapse, and the patient's condition is currently in partial remission.

Nonseminomatous Extragonadal Germ Cell Tumor Presenting As Early Pericardial Tamponade

Multiple different types of mediastinal masses may be encountered on imaging techniques in symptomatic and asymptomatic patients. The most frequent mediastinal masses in adults are thymoma, lymphoma, thyroid masses, and germ cell tumors. Potential complications of these masses due to localized invasion include hemoptysis, post-obstructive pneumonia, and superior vena cava syndrome. Pericardial tamponade is usually secondary to pericarditis, trauma, infections, radiation, uremia, vascular diseases, and uremia. However, this report presents a case of a young patient who was found to have a large pericardial effusion and early signs of pericardial tamponade, which have not previously been reported as complications of extragonadal germ cell tumors, to the best of our knowledge.