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Neonatal thoracic germ cell tumor with rare association of aortic aneurysms and arteriovenous malformation - A case report
*Corresponding author: Mohita Rajendra Bafna, Department of Radiology, Lokmanya Tilak Municipal Medical College and General Hospital, Mumbai, Maharashtra, India. mohitabafna17@gmail.com
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Received: ,
Accepted: ,
How to cite this article: Bafna MR, Sonve A, Chavan A. Neonatal thoracic germ cell tumor with rare association of aortic aneurysms and arteriovenous malformation - A case report. Case Rep Clin Radiol. doi: 10.25259/CRCR_28_2025
Abstract
Intrathoracic germ cell tumors in neonates are unusual, possessing a diagnostic challenge, especially when associated with vascular anomalies such as spinal arteriovenous malformation and aneurysms of the descending thoracic aorta. The use of computed tomography not only helps in diagnosis but also in understanding the extent and invasion of the lesion with associated complications and other concurrent pathologies, which further aids in management. This case report highlights a complex neonatal thoracic pathology requiring detailed cross-sectional imaging for accurate diagnosis and management.
Keywords
Aneurysms
Arteriovenous malformation
Extragonadal germ cell tumor
Neonate
Thorax
INTRODUCTION
Neonatal thoracic pathologies pose a diagnostic challenge due to their complexity and rarity with extragonadal germ cell tumors (GCT) being a further rare subset. The case discussed below is a preterm neonate with intrathoracic malignant GCT and a myriad of other findings creating a diagnostic enigma.
CASE REPORT
An 8 day old, late preterm girl neonate, with delayed crying post-birth, was referred for evaluation of respiratory distress. Initially, congenital pulmonary airway malformation was suspected despite unremarkable antenatal anomaly scan reports and underwent computed tomography (CT) chest with non-ionic iodine-containing contrast media for further evaluation. It revealed a large, multiloculated, multiseptated cystic lesion in the posterior mediastinum, predominantly on the right, in subcarinal location, causing near complete collapse and consolidation of right lower lobe of lung with right sided pleural effusion [Figure 1]. The lesion exhibited heterogeneous, peripheral, and septal enhancement receiving arterial supply from adjacent intercostal arteries and descending thoracic aorta.
- Axial, sagittal and coronal reconstruction of plain and contrast phases reveal (a) multiloculated, multiseptated cystic lesion (white arrow) in the posterior mediastinum predominantly on the right, in subcarinal location. (b and d) It shows post contrast enhancement (white arrow). (C) Associated findings include right sided pleural effusion (star) and near- complete collapse consolidation of right lower lobe (arrowhead).
Multiple, irregular, focal outpouchings are noted arising from the descending thoracic aorta, suggestive of aneurysms [Figure 2]. In addition, abnormal tortuous vessels with aneurysmal dilatations were noted within the spinal canal, suggestive of a spinal arteriovenous malformation (AVM) [Figure 2].
- Axial, oblique coronal and coronal reconstruction of arterial phase images reveal (a-b) multiple irregular outpouchings (white arrows) noted arising from descending thoracic aorta (white stars). (c-d) Also noted are abnormal tortuous dilated vessels within the spinal canal, suggestive of a spinal arteriovenous malformation (black arrowheads).
The combination of the above-mentioned findings, including a large multicystic thoracic mass lesion with vascular malformation and aneurysms, presents a diagnostic conundrum. Differential diagnoses considered included
Mediastinal germ cell tumor with vascular malformation
Embryonal malignancy with vascular malformation or ganglioneuroblastoma
Atypical mycobacterial or fungal infection with mycotic aneurysms
Complex congenital cystic lesions.
Histopathological correlation and pleural fluid cytology were suggested.
Pleural fluid was negative for fungal culture. Due to the critical condition of the neonate, an urgent ultrasound-guided biopsy of the multiloculated lesion was performed.
Histopathology revealed atypical spindle to polygonal-shaped cells with areas of necrosis, which in places were arranged around small capillaries.
Differential diagnosis of (1) rhabdomyosarcoma and (2) GCT.
Immunohistochemistry markers were done with Grocott Methenamine Silver (GMS) negative, Pan-cytokeratin (PANCK) positive, and desmin negative in tumor cells; hence, a diagnosis of malignant GCT favored [Figure 3].
- Figure 3: Histopathology (40x) revealed (a) On H&E (Hematoxylin and Eosin) staining atypical spindle shaped cells (b) GMS negative, (c) PAN - CK (Pan-cytokeratin) positive and (d) desmin negative in tumour cells.
Unfortunately, the patient was pronounced deceased due to a continuous decline in respiratory status.
DISCUSSION
GCTs arising from primordial germ cells are a rare entity in children, representing only 3.5% of malignancies in childhood.[1] GCTs are gonadal or extragonadal in location. The extragonadal sites are very rare and occur along the midline due to aberrant embryologic migration of germ cells to the genital ridge. The extragonadal sites include the pineal gland, suprasellar, mediastinum, retroperitoneum, and sacrum.[2] Mediastinal GCTs are the most common type of extragonadal GCTs (50–70%).[3]
Pathological subtypes
Germ cell tumors are classified on the basis of tissue differentiation into tumors showing no tissue differentiation (seminoma/germinoma) and tumors showing embryonic (embryonic cell tumors and teratoma) and extraembryonic (choriocarcinoma and yolk sac tumor [YST]) tissue differentiation. GCTs can also be benign or malignant.
Most common mediastinal germ cell tumor is mature teratoma (Benign), accounting for 70~75% of all mediastinal GCTs. Only 25~30% GCTs in the mediastinum are malignant.[4]
Demographics
Extragonadal germ cell tumor displays a male preponderance exhibiting a bimodal age distribution, peaking once during infancy to age five and again throughout adolescence and early adulthood. Seminomas are more common in the second peak, but teratomas and YSTs are more common in the first. Teratomas may also present as congenital mediastinal masses.[5]
Radiological features
GCT is a heterogeneous group of neoplasms, making prospective radiologic diagnosis challenging; however, certain imaging characteristics do reflect or point toward a particular pathological subtype. Furthermore, histologically analogous GCTs at varying sites have comparable radiologic features and, therefore, allow radiologists to diagnose these tumors correctly.
Seminoma/germinoma appears as lobulated, homogeneous, and mildly enhancing solid masses. Cysts, hemorrhage, and calcification are rarely seen. Local invasion is uncommon, but metastases most often to the lymph nodes and, less commonly, to the lungs, bone, or liver may be present GCTs with tissue differentiation are heterogeneous masses with areas of necrosis, hemorrhage, or cystic degeneration. Fat planes between these tumors and adjacent organs are often obliterated. Invasion of adjacent organs may be present. Metastases to liver and lung, followed by lymph nodes, brain, and bones, may be present. A combination of calcification, fat, fluid, and soft tissue in a mediastinal mass is diagnostic of teratoma. Mature teratoma, a subtype of benign mediastinal GCTs, is the most common on histology.
The radiologic findings of GCTs are often non-specific, and tissue diagnosis might be required for differentiation from other common masses, such as lymphomas, thymic neoplasms, metastatic lymph nodes, thyroid masses, and neurogenic tumors. Imaging plays a crucial role as CT thorax with contrast provides detailed information on the tumor’s size, extent, and vascular involvement, crucial for planning surgical and chemotherapeutic interventions.
Clinical features
Symptoms of GCTs depend on their location and are due to mass effect, depending on their size. For example, in the above-mentioned case report, the intrathoracic extragonadal germ cell tumor was causing respiratory distress and chest pain.
Treatment
Germ cell tumors in the pediatric population generally have a good prognosis with a treatment strategy of complete resection followed by adjuvant chemotherapy. If the tumor cannot be completely resected at the time of diagnosis, a biopsy followed by neoadjuvant chemotherapy is usually performed.[6]
DIFFERENTIAL DIAGNOSIS
Malignant germ cell tumor with vascular malformation.
Less likely atypical infective etiology with mycotic aneurysms.
CONCLUSION
The above presented case is unusual with the association of GCT with AVM and aneurysms and to the best of our knowledge has not been encountered in the literature. It also underscores the importance of comprehensive cross-sectional imaging modalities such as CT for such complex mass lesions.
TEACHING POINTS
Cross-sectional imaging is an important tool for diagnosis and determining extent, invasion, and other complications of intrathoracic pathologies, especially in a neonate.
Intrathoracic germ cell tumor in a neonate is a rare diagnosis, especially when associated with vascular anomalies.
Pathological subtypes of GCTs at varying sites have similar radiologic features and therefore help in diagnosis.
MCQ’s
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What is the most common site for extragonadal germ cell tumor?
Mediastinum
Retroperitoneum
Sacrococcygeal
Suprasellar
Answer key: a
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Combination of calcification, fat, fluid, and soft tissue in a germ cell tumor is diagnostic of?
Seminoma
Germinoma
Teratoma
Choriocarcinoma
Answer key: c
Author contributions:
MRB, AS, AC: Concepts, design, definition of intellectual content, literature search, manuscript preparation, manuscript editing and review.
Ethical approval:
Institutional Review Board approval is not required.
Declaration of patient consent:
The authors certify that they have obtained all appropriate patient consent forms. In the form, the patients have given their consent for their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Conflicts of interest:
There are no conflicts of interest.
Use of artificial intelligence (AI)-assisted technology for manuscript preparation:
The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.
Financial support and sponsorship: Nil.
References
- Germ cell tumors in adolescents and young adults. J Oncol Pract. 2019;15:433-41.
- [CrossRef] [PubMed] [Google Scholar]
- Origins and molecular biology of testicular germ cell tumors. Mod Pathol. 2005;18:S51-60.
- [CrossRef] [Google Scholar]
- Mediastinal germ cell tumours: Where we are and where we are going-a narrative review. Mediastinum. 2022;6:7.
- [CrossRef] [PubMed] [Google Scholar]
- Extragonadal malignant germ cell tumors: A clinicopathological and immunohistochemical analysis of 48 cases at a single Chinese institution. Int J Clin Exp Pathol. 2015;8:5650-7.
- [Google Scholar]
- Pediatric mediastinal germ cell tumors. Mediastinum. 2019;3:30.
- [CrossRef] [PubMed] [Google Scholar]
- Pediatric extracranial germ cell tumors: Review of clinics and perspectives in application of autologous stem cell transplantation. Cancers (Basel). 2023;15:1998.
- [CrossRef] [PubMed] [Google Scholar]