Table of ContentsView AllTable of ContentsTypesSymptomsCausesDiagnosisTreatmentPrognosisCoping
Table of ContentsView All
View All
Table of Contents
Types
Symptoms
Causes
Diagnosis
Treatment
Prognosis
Coping
Thymomais a tumor (growth) of the thymus gland. It may be benign or malignant (cancer). Thethymus glandis part of thelymphatic system—the tissues that help produce, store, and transport white blood cells.The thymushelps white blood cellscalled T lymphocytes grow and multiply. It’s found in the chest behind the breastbone.
Thymomas are rare. There are only about 400 cases of thymomas per year in the United States. Thymic carcinoma accounts for 20% of all tumors in the thymus.
This article will review the types of thymoma and the symptoms of this cancer, its causes, risk factors, diagnosis, treatment, and prognosis. It will also cover how to cope with a diagnosis of thymoma.
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Types of Thymoma
Thymoma is often lumped together withthymic carcinomas.They are both thymic epithelial tumors (TETs) that start from cells in the outer layer of the thymus. The two types of TET are different, though. Thymoma cells look normal, grow slowly, and usually stay in the thymus.
In thymic carcinoma, the cancer cells look abnormal and grow quickly. Thymic carcinoma is more likely to spread to other body parts and is more challenging to treat.They make up about 20% of TETs.
Type A thymomas look the closest to normal thymus cells. It’s the rarest type but has the best prognosis.Overall survival is reported to be 100% at five and 10 years.
Type AB or mixed thymomas look like Type A thymomas but have areas of more abnormal cells. The overall survival is reported to be 80% to 100% at five and 10 years.
Type B is divided into three types.
The most common types of thymoma are type AB and type B2. The least common is type A.
Thymoma Symptoms
Symptoms of thymoma are typically mild. Often, people with a thymoma don’t have symptoms. Many thymomas are found when someone is getting a scan for another reason.
Symptoms that do show up can include:
If the tumor presses on a large blood vessel, it may produce these symptoms:
Thymomas are associated with the development of autoimmuneparaneoplasticsyndromes. These diseases develop in people with cancer, where the immune system attacks the body’s normal cells. They include:
Researchers don’t know much about what causes thymomas or other thymus cancers.Researchers haven’t found any specific inherited, environmental, or lifestyle risk factors that increase your risk of thymoma.
Thymomas are seen more often in middle-aged adults than in younger people and are most common in those in their 70s. In the United States, thymomas are diagnosed more often in Asians and Pacific Islanders than those of other ethnicities.
If a healthcare provider thinks you may have a thymoma, they’ll start with a thorough checkup, including a physical exam and a discussion of your medical and family history.
They’ll likely order a variety of imaging tests of the thymus. Thymomas are generally diagnosed based on how the thymus gland looks on these imaging tests.
Blood tests don’t necessarily help diagnose thymoma but can help screen for related autoimmune syndromes.
They may want to take a thymus sample to review in the lab (called a biopsy), but this isn’t always needed. They’re more likely to wait until surgery is performed for treatment.
Thymoma is slow growing and not likely to spread, so it typically has a good prognosis. The five-year overall survival rate is approximately 90% for thymoma.
For thymus cancers, the survival rates are a little worse. Overall the five-year survival rate for thymus cancers is 71%. The prognosis is better for thymus cancers caught early before they spread.
Factors that can impact a thymoma prognosis include:
While thymomas can often be successfully treated, they may come back much later. Cancer can reappear in the thymus or other parts of the body.
Thymomas are also linked to a higher risk of different types of cancer.Your healthcare provider will likely ask you to come back for regular follow-ups throughout your life.
A diagnosis of thymoma can be very upsetting. Symptoms from an associated autoimmune paraneoplastic syndrome it can affect your quality of life. Cancer that has already spread or can’t be removed with surgery may make you scared for your life, and more intensive treatment can cause stress and physical symptoms.
Bring any questions to your treatment team so you understand your choices in treatment, what side effects may occur, andyour prognosis. Knowing your challenges can help prepare you and allow you to plan for additional support.
Your family and friends can be resources for emotional and physical support. It can be challenging to ask for support, but you can benefit from this help during diagnosis and treatment.
Even if you are symptom-free and your treatment is successful, you may have strong feelings, including joy, concern, relief, guilt, and fear.
Cancer can make you very anxious about your health and how to deal with everyday life. Returning for required follow-up visits may cause stress.
While many thymomas can be treated with surgery alone, a thymoma can come back and require additional treatments. It’s normal to worry about this.
Ask your treatment team about online or in-person support groups for people with thymoma or similar conditions. This may also be a time to get the help of a mental health professional or counselor.
Summary
Thymoma is a rare neoplasm of the thymus gland. Thymomas are classified and lettered from best prognosis (A) to worst (C) based on how abnormal their cells look and how likely they are to spread. Some of them behave literally like benign tumors. Others have malignant behavior and tend to invade locally and spread at a distance.
Type A is the best prognosis but the least common. Type AB and type B2 are the most common. More common. Type B1, B2, and B3 thymomas are more likely to have a worse prognosis than Type A. Type C is also called thymic carcinoma and is the most dangerous thymoma.
Thymoma symptoms include cough and hoarseness, breathing problems, chest pain, and swelling in the upper body. There are no known causes of thymomas. Instead, they are diagnosed with imaging scans.
Surgery is the most common and sometimes only treatment needed for thymomas. Other treatment options include radiation, chemotherapy, targeted therapy, and clinical trials.
A Word From Verywell
A thymoma diagnosis may be frightening as you may not know how dangerous or malignant your tumor is until surgery. Talk to your care team about your prognosis and treatment for your symptoms. While the prognosis and survival rates are suitable for many types of thymoma, seek support during this challenging time.
19 Sources
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