Standardized definitions and concepts of radicality during minimally invasive thymoma resection

Abstract

Radical thymectomy is the gold standard treatment for thymoma; in particular, completeness of surgical resection of a well-encapsulated thymoma and adequate margins are considered the most important prognostic factors. According to the International Thymic Malignancy Interest Group instructions, in fact, the thymus should be resected en bloc with its upper cervical poles and the surrounding mediastinal fat and through a no-touch surgical technique. For years, the open approaches have been considered the gold standard treatment for thymic masses, because of technical advantages and proved good oncological results. When applied to properly chosen patients on the basis of the tumor stage, dimension, and histology, minimally invasive approaches could be as effective as open ones in terms of long-term outcomes. To accomplish a minimally invasive thymoma resection, several minimally invasive techniques (transcervical, subxiphoid, thoracoscopic, and robotic) have been described, each presenting advantages and drawbacks. Moreover, when dealing with early stage neoplasms, many authors have proposed to perform the thymomectomy alone, not involving the rest of the thymic gland, but evidence is still imprecise and vague, and some studies have described a higher rate of local recurrence when using this technique. Finally, many studies suggest that surgeons with expertise in minimally invasive lymphadenectomy for lung cancer may easily endorse the idea of nodal dissection, to be performed at least in advanced thymomas involving neighboring structures, large masses, and thymic carcinomas.

Keywords

Thymoma / thymectomy / minimally invasive techniques / radicality

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