Case presentation

A 30-year-old medically free male patient presented to the emergency department with a one-week history of cough and two weeks of productive sputum. He was afebrile and hemodynamically stable but exhibited prominent neck and forehead vein distension. The patient was alert and oriented (Glasgow Coma Scale (GCS) 15/15) with no neurological deficit or cyanosis. He reported mild weight loss and intermittent low-grade fever. Physical examination showed no lymphadenopathy or peripheral edema.

Chest X-ray revealed a large right-sided mediastinal mass (Figure 1). Contrast-enhanced CT chest demonstrated a lobulated, heterogeneously enhancing anterior mediastinal mass measuring 8.6 × 15.8 × 8.7 cm, encasing and compressing the SVC with complete occlusion (Figure 2). The mass also compressed the right pulmonary artery and veins and was inseparable from the pericardium. Mild bilateral pleural effusions (right greater than left) and a small pericardial effusion were noted.

Figure 1: Chest X-ray showing right-sided mediastinal opacity mass (arrow)

Figure 2: Contrast-enhanced CT chest showing anterior mediastinal mass encasing SVC (arrow)CT: computed tomography; SVC: superior vena cava

Histopathology from ultrasound-guided biopsy revealed necro-inflammatory tissue with atypical cells showing nuclear anaplasia. Immunohistochemistry was positive for glypican-3, AFP, and cluster of differentiation 117 (CD117), and negative for leukocyte common antigen (LCA), cluster of differentiation 30 (CD30), cluster of differentiation 16 (CD16), and placental alkaline phosphatase (PLAP). Tumor markers showed AFP of 686.87 ng/mL (elevated) and β-hCG of 0.93 IU/L (normal). Therefore, the diagnosis of NSGCT was made.

Follow-up echocardiography demonstrated pericardial effusion (2.5 cm behind the right atrium) with impending tamponade. Consequently, pericardiocentesis drained malignant fluid, and the patient received six months of platinum-based chemotherapy. The patient received combination chemotherapy consisting of oxaliplatin 150 mg intravenously, paclitaxel 120 mg intravenously, and gemcitabine hydrochloride 1200 mg intravenously, each administered once during the treatment cycle. Supportive treatment included filgrastim 300 mcg subcutaneously once daily for three days, in addition to antiemetic and hypersensitivity prophylaxis, with marked reduction in tumor size. However, SVC occlusion persisted.

A multidisciplinary meeting recommended surgical resection with vascular reconstruction. Median sternotomy was performed under general anesthesia, and the mediastinal mass was carefully dissected (Figure 3). The mass was found to invade the SVC; therefore, segmental SVC resection followed by PTFE graft anastomosis was completed under cardiopulmonary bypass (Figure 4). Adhesiolysis of the pericardium and right lung was performed, and the specimen was excised using an Endo GIA stapler (Medtronic; Minneapolis, Minnesota, USA) (Figure 5).

Figure 3: Intraoperative image showing the anterior mediastinal mass. The arrow indicates the region of tumor involvement within the operative field

Figure 4: Intraoperative image showing SVC reconstruction with a PTFE graft. The arrow indicates the reconstructed SVC/PTFE graft segmentSVC: superior vena cava; PTFE: polytetrafluoroethylene

Figure 5: Intraoperative image showing the excised mediastinal mass

The patient tolerated the operation well and was transferred to the Cardiac Surgery Intensive Care Unit (ICU) in stable condition, where he was extubated after two hours. One-month postoperative chest X-ray showed clear lung fields and no recurrent right-sided mediastinal opacity, consistent with absence of the previously seen mass (Figure 6). Postoperative contrast-enhanced CT chest confirmed patency of the reconstructed SVC/PTFE graft on axial and sagittal views (Figures 7-8). The patient had no recurrence of symptoms or other complaints. He was prescribed two additional cycles of adjuvant chemotherapy and continues to be followed in clinic with surveillance imaging.

Figure 6: Postoperative chest x-ray showing clear lung fields and absence of the previously seen mediastinal mass. The arrow indicates the postoperative region previously occupied by the mass

Figure 7: Postoperative contrast-enhanced chest CT axial view showing a patent SVC/PTFE graftSVC: superior vena cava; PTFE: polytetrafluoroethylene

Figure 8: Postoperative contrast-enhanced chest CT sagittal view showing a patent SVC/PTFE graft. The arrow indicates the reconstructed graft segmentSVC: superior vena cava; PTFE: polytetrafluoroethylene