Minimally invasive surgical procedures for thymic disease in Asia

Abstract

Video-assisted thoracic surgery (VATS) procedures for thymic tumors and myasthenia gravis were introduced in Asia in the middle 1990s in at least two regions, Hong Kong and Japan. To overcome difficulties in obtaining a wide view of the anterior mediastinum, several methods for lifting the sternum or anterior chest wall have been presented, mainly by Japanese surgeons. More recently, single port VATS through a subxiphoid incision was also introduced in Japan. The long-term outcome of a VATS extended thymectomy for myasthenia gravis has been shown to be comparable to that of a trans-sternal extended thymectomy, while the long-term outcome of a VATS thymectomy for thymic epithelial tumors remains to be elucidated. Nevertheless, its indication for tumors in an early stage is now widely accepted, and the number of VATS procedures is steadily increasing in Japan and China. Single-port VATS through a subxiphoid incision was developed in Japan and might become accepted as a useful approach in the near future when combined with robot-assisted thoracoscopic surgery. In addition, robot-assisted thoracoscopic surgery for the thymus has also been introduced in some areas in Asia. Although few of those surgical procedures for the thymus have been performed, results obtained thus far indicate that it might be preferable to lung resection. Several novel minimally invasive thymectomy techniques have been invented and developed in Asia, and further advancements in this field by Asian surgeons are anticipated.

Keywords: Video-assisted thoracic surgery (VATS); myasthenia gravis; robot-assisted surgery; thymoma.

Figure 1

Anterior chest wall lifting method using costal hooks (red arrows), developed by Ohta et al.

Figure 2

Thymic vein (white arrow) shown by 3D imaging.

Figure 3

Extended thymectomy by bilateral VATS (13). VATS, video-assisted thoracic surgery. Available online: http://www.asvide.com/articles/1619

Figure 4

Annual numbers of surgical procedures for thymic epithelial tumors performed in Asia. (A) Number of surgeries for thymic epithelial tumors (total and VATS); (B) proportion of VATS procedures for thymic epithelial tumors performed in China. VATS, video-assisted thoracic surgery.

Figure 5

Number and proportion of VATS procedures for extended thymectomy for myasthenia gravis according to presence or absence of association with thymoma. VATS, video-assisted thoracic surgery.

Figure 6

Annual trend in number of surgical procedures for thymic epithelial tumors performed in China. (A) Number of surgical procedures for thymic epithelial tumors in patients with Masaoka stage 1 or 2 disease (total and VATS); (B) proportion of VATS procedures for thymic epithelial tumors. VATS, video-assisted thoracic surgery.