Uncommon Experience and Expertise with Thymomas and Thymic Tumors

By James Huang, MD  |  Monday, February 10, 2014

Thymomas and other thymic tumors, such as thymic carcinomas and thymic carcinoids, are uncommon neoplasms that occur in the chest. Memorial Sloan Kettering is unique in offering specialized expertise in diagnosing and treating these rare and often complex cases. Whereas many hospitals see only one or two cases a year, our institution has treated more than 150 patients with thymomas and other thymic tumors during the last five years. Owing to the high volume of cases we see, our dedicated multidisciplinary team, and our robust research program, Memorial Sloan Kettering is widely recognized as an international leader in this domain.

In general, thymic tumors are associated with a more favorable prognosis than other malignancies of the chest. However, the anatomic location of these tumors and their proximity to critical structures can make their treatment challenging. As these tumors arise from the thymus gland, the frequent association of autoimmune diseases, such as myasthenia gravis, can further complicate their management. For these reasons, a highly coordinated multidisciplinary effort involving thoracic surgeons, medical oncologists, radiation oncologists, neurologists, pathologists, and radiologists is needed. At Memorial Sloan Kettering, we are fortunate to have such a team, whose members all share a special interest in these rare diseases.

Advanced Surgical Techniques and Coordinated Care

In many cases, early-stage tumors of the thymus are identified incidentally, during the workup of unrelated issues. Often, the tumors are treatable through minimally invasive techniques. Although these tumors have traditionally been approached through a sternotomy, many small and moderately sized thymomas can be completely resected through thoracoscopic approaches. With the assistance of surgical robotics, these minimally invasive operations can be performed with a high degree of precision and minimal discomfort. Our patients are often able to return home after only an overnight stay in the hospital. Memorial Sloan Kettering thoracic surgeons are among the leaders in the development and use of these minimally invasive and robotic techniques.

Larger, more advanced stage thymic tumors can pose a significant challenge, not only because of their size but also because of their tendency to invade adjacent organs and vessels and develop pleural metastases. These tumors often require coordinated team care with combined modality treatment that incorporates chemotherapy, radiation, and surgery.

The surgery required for these malignancies can be extensive, and achieving optimal results demands considerable experience with these extended resections, which often involve extrapleural pneumonectomy or reconstruction of the vena cava. The complexity of the treatment required for these patients mandates care by an experienced multidisciplinary team to achieve optimal outcomes.

Unique Trial and Research Background

Currently, Memorial Sloan Kettering offers the only clinical trial available worldwide for patients with these advanced but potentially operable tumors. This trial combines the novel use of a targeted agent, cetuximab, with standard chemotherapies in a neoadjuvant setting.

Memorial Sloan Kettering’s Thymoma Working Group spearheads much-needed research efforts in this area. Our thymic tumor database includes several hundred cases, and the availability of corresponding tumor biospecimens has been critically important to the efforts to characterize the molecular bases of these rare neoplasms. Members of the group, many of whom serve in prominent roles in international organizations focused on these tumors, have helped lead the development of the current diagnostic and treatment paradigms.

Our patient-oriented cancer guide on thymoma and thymic tumors provides information about our physicians and more details about the treatment of thymoma and other thymic malignancies at Memorial Sloan Kettering.

Figure 1. Replacement of the right hemithorax and encasement of the superior vena cava by locally advanced thymoma Enlarge Image Figure 1. Replacement of the right hemithorax and encasement of the superior vena cava by locally advanced thymoma

Figure 2. Mediastinal thymoma involving the great vessels Enlarge Image Figure 2. Mediastinal thymoma involving the great vessels

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