Background: Patients with mediastinal masses present unique challenges for anesthesiologists. If located in the anterior mediastinum they can cause obstruction of the airways and large vessels such as the pulmonary arteries and the superior vena cava (SVC). Case Report: During surgical procedures, acute cardiorespiratory collapse can be linked to general anesthesia due to tumor-related compression syndromes. Local anesthesia can be chosen in order to maintain spontaneous ventilation. Conclusion: This article aims to describe the case of a patient having a large anterior mediastinal mass with significant compressive symptoms who underwent thoracoscopy with biopsy.