Large thoracic tumour without superior vena cava syndrome

Area of Science:

• Cardiology
• Thoracic Surgery
• Radiology

Background:

• A 62-year-old male smoker presented with hemoptysis and a tracheal tumor.
• The tumor caused significant stenosis of the right main bronchus and right upper lobar bronchus.
• Contrast-enhanced CT revealed a large tumor, mediastinal lymphadenopathy, and a vessel near the aortic arch.

Purpose of the Study:

• To investigate the absence of superior vena cava (SVC) syndrome despite significant SVC compression by a tracheal tumor.
• To highlight the role of a persistent left superior vena cava (PLSVC) in this clinical presentation.
• To discuss the embryology, prevalence, and clinical significance of PLSVC.

Main Methods:

• Plain chest X-ray
• Bronchoscopy
• Contrast-enhanced chest computed tomography (CT)

Main Results:

• A 7.2 × 4.9 cm tracheal tumor was identified, infiltrating the right main bronchus (75% stenosis) and right upper lobar bronchus (near total occlusion).
• The tumor constricted the right superior vena cava (SVC), yet SVC syndrome was absent.
• The patient possessed a persistent left superior vena cava (PLSVC), which served as the primary drainage pathway for head and neck veins.

Conclusions:

• Persistent left superior vena cava (PLSVC) is the most common thoracic venous anomaly, occurring in 0.3-0.5% of the population.
• PLSVC can explain the absence of SVC syndrome in cases of SVC compression.
• Understanding PLSVC is crucial for interpreting thoracic imaging and managing related clinical scenarios.