By Ann Miller Baker
When news broke this week that Congressman Elijah Cummings of Maryland had battled a rare cancer for decades before his death in October, many wondered about this cancer that had dogged the powerful chair of the House Oversight and Reform Committee.
According to the National Cancer Institute, thymic carcinoma is a cancer that develops in cells on the outside surface of the thymus. This small organ that sits under the breastbone is part of the lymph system, making white blood cells call lymphocytes that fight infections. Thymic carcinoma and a related cancer called thymoma are exceedingly rare. Less than one person in 1.5 million will develop a thymoma. Even fewer are diagnosed with thymic carcinoma, which accounts for only 0.06% of all tumors of the thymus.
Though rare, such cancers are regularly treated at Moffitt Cancer Center, according to radiation oncologist Dr. Thomas Dilling.
“Cancers of the thymus gland are rare tumors, usually early stage, and typically treated with surgery, though sometimes post-operative radiotherapy is employed as well,” says Dilling. “In more advanced cases, chemotherapy also plays an important role. Because they are rare tumors, not many oncologists have much experience with them, though we have a robust team of specialists at Moffitt who manage these rare tumors.”
Because these tumors of the thymus often do not cause early signs or symptoms, many are identified through routine chest x-rays for other issues. Approximately 30% of patients with thymomas may present with neurologic symptoms. Patients with thymic carcinomas may also present with a persistent cough, chest pain or trouble breathing.
Surgery is usually the first treatment option for these types of cancers. Depending on the cancer’s spread, lymph nodes or other tissues may be removed as well. After surgery, radiation therapy, chemotherapy and/or hormone therapy may also be necessary. Patients who are not candidates for surgical resection are typically treated with radiotherapy and, often, chemotherapy. Newer types of treatments for thymus cancers are still in clinical trials.
The cure rate for thymomas, which are typically relatively benign, is high. For the more aggressive thymic carcinomas, as Rep. Cummings had, however, the cure rate is only 30% to 50%. Even if the tumor responds to initial treatments, it is not uncommon for these cancers to recur. As such, lifelong follow-up is necessary, as was the case for the late Rep. Cummings.