Which way is up? Policies and procedures for surgeons and pathologists regarding resection specimens of thymic malignancy

Abstract

Thymic malignancies are relatively uncommon, which mandates that the experience from many different institutions be combined to achieve a better understanding of the disease. Nevertheless, this is hampered by many ambiguities in how results are reported and interpreted. This problem is aggravated by the fact that smaller institutions often encounter these tumors only sporadically. A prerequisite to interinstitutional collaboration is a common language and consistency in the definition of findings (e.g., whether a complete resection was accomplished or not). This article summarizes the policies adopted by the International Thymic Malignancy Interest Group (ITMIG) regarding handling of a resection specimen by the surgeon and pathologist and reporting of the surgical and pathologic findings. These policies are based as much as possible on reported evidence, but this is lacking or limited in many areas. Nevertheless, adoption of a consistent approach is crucial to conduct valid studies moving forward that can clarify areas of uncertainty. This publication addresses only how to handle and process the tissue specimen at the time of a resection. It does not address handling and interpretation of biopsies or cytologic specimens, which is an important topic that is addressed in a separate publication.1 This article is limited to an open resection (by sternotomy). Although other approaches are sometimes used (e.g., thoracoscopy), the issues involved are also covered in another publication.2 Furthermore, this article is written with the assumption that resection of a thymoma involves a complete thymectomy along with any adjacent structures that may be involved and that the goal is a complete (R0) resection (i.e., not debulking).