Video-assisted thoracoscopy versus open approach in patients with Masaoka stage III thymic epithelial tumors

BACKGROUND: The treatment options for Masaoka stage III thymic epithelial tumors are diverse, mainly because the lesions infiltrate the neighboring organs, major vascular structures, with different scopes, extents, and manners. Surgical treatment is the main treatment for the patient in this stage. However, for minimally invasive or open surgery, the current controversy remains large. This study aimed to investigate the feasibility and indications of minimally invasive resection in the treatment of stage III thymic tumors. METHODS: Twenty-six patients with Masaoka stage III thymic tumors who underwent surgery were enrolled in the study. Among them, group A with 8 patients underwent thoracoscopic resection and group B with 18 patients (including one open-converted patient) underwent semi-sternotomy or full-sternotomy resection. The groups were compared with each other in terms of the characteristics of patients, tumors, and perioperative period. RESULTS: There were no significant differences in patients’ characteristics, WHO classification, and complications between the two groups (P>0.05), but the tumors in group B were significantly larger than those in group A (P<0.05). In group B, the lesions infiltrated the superior vena cava and the phrenic nerve more frequently than that of group A (P<0.05). There was no significant difference between the two groups in the involvement of left innominate vein, pericardium, and lung (P>0.05). Tumor size, the involvement of superior vena cava and phrenic nerve were important factors in the determination of minimally invasive surgery for Masaoka stage III thymic tumor (P<0.05). CONCLUSIONS: For Masaoka stage III thymic tumors, neighboring organs involved were noted to be important factors in successful minimally invasive tumor resection. Tumor size and involvement of phrenic nerve and superior vena cava were found to be the variables that hindered successful video-assisted thoracoscopy (VATS) resection. Thus, minimally invasive resection is acceptable in the treatment of selected cases of Masaoka stage III thymic tumors.