Thymic epithelial tumors (TET) are uncommon tumors of the anterior mediastinum. Despite their rarity, they are actually the most common tumor type located in this mediastinal compartment. TET are comprised of three main types: thymoma (85–90%), thymic carcinoma (8–12%), and neuroendocrine tumors of the thymus (1–4%). Given the rare incidence of TET, it is not surprising that evidence-based practice patterns have not evolved to the extent that has been seen with other, more common malignancies. The published literature consists mainly of case reports and series, a few prospective, observational clinical trials, and no randomized controlled trials. Perhaps the most significant reason for the paucity of high quality published research is any given institution sees only a handful of cases per year, and the lack of the ability to perform coordinated research amongst centers.
The only way to conduct high quality research regarding TET is to develop the infrastructure and commitment to coordinate studies between multiple institutions. To this end, a notable organization that has taken on this challenge in China is the Chinese Alliance for Research in Thymomas (ChART). Established in 2012, ChART organized retrospective data from over 2,300 patients from multiple institutions into a single database for research purposes. This dataset provides the basis for many of the studies presented in this Focused Issue of the Journal of Thoracic Disease.
In addition to performing its own coordinated research, ChART has also contributed its data to the much larger, worldwide retrospective database of the International Thymic Malignancy Interest Group (ITMIG). ITMIG, founded in 2010, is an organization dedicated to research, education and support for patients with thymic malignancies with over 600 members worldwide. Building upon its success in developing its retrospective database comprising data from over 7,000 cases, ITMIG has also developed a prospective data collection mechanism that is utilized by member institutions on six continents, and is linked to a virtual tissue bank. These extremely large datasets allow ITMIG and its members to perform research studies that were never conceivable in the past due to the rarity of TET. On the educational front, ITMIG has established standard practice guidelines for clinicians who treat patients with TET, and has produced other educational tools and documents aimed at educating not only physicians, but also patients about these rare tumors.
It is only through such collaborative mechanisms and organizations that knowledge regarding thymic tumors will be advanced in the future, which should also serve as model for performing research for other rare diseases. This Focused Issue of the Journal of Thoracic Disease is evidence of the progress allowed only through such collaboration.