Chemotherapy (chemo) uses anti-cancer drugs that are given intravenously (IV or into a vein), as an injection (shot), or by mouth. These drugs enter the bloodstream and reach the whole body, making this treatment useful for cancer that may have spread to organs beyond the thymus.
Chemo may be used in these situations:
- It may be given after surgery to try to kill any cancer cells that may have been left behind because they were too small to see. This is called adjuvant treatment.
- It may be given before surgery to try to shrink tumors so that they can be completely removed. This is called neoadjuvant therapy.
- Chemo may be the main treatment for people who have advanced cancer or are not healthy enough for surgery. .
- Chemo is sometimes combined with radiation to help it work better. This is known as chemoradiation or chemoradiotherapy.
Doctors give chemo in cycles, with each period of treatment followed by a rest period to allow the body time to recover. Chemo cycles generally last about 3 to 4 weeks, and treatment typically involves 4 to 6 cycles. Chemo is often not recommended for people in poor health, but advanced age by itself is not a barrier to getting chemo.
Several chemo drugs may be used in the treatment of thymomas and thymic carcinomas, including:
- Doxorubicin (Adriamycin®)
- Cyclophosphamide (Cytoxan®)
- Ifosfamide (Ifex®)
- Vincristine (Oncovin®)
- Etoposide (VP-16)
- Paclitaxel (Taxol®)
- Pemetrexed (Alimta®)
- 5-fluorouracil (5-FU)
- Gemcitabine (Gemzar®)
The corticosteroid drug prednisone is often given with chemo.
These drugs are usually given in combination to try to increase their effectiveness. For example, the combination of cisplatin, doxorubicin, and cyclophosphamide (called CAP) with or without prednisone is often used to treat thymoma. The combination of carboplatin and paclitaxel may be used to treat thymic carcinoma.
Possible side effects of chemotherapy for thymus cancer
Chemo drugs work by attacking cells that are dividing quickly, which is why they work against cancer cells. But other cells in the body, such as those in the bone marrow, the lining of the mouth and intestines, and the hair follicles, also divide quickly. These cells are also likely to be affected by chemo, which can lead to certain side effects.
The side effects of chemo depend on the type and dose of drugs you are given and how long they are used. Side effects can include:
- Hair loss
- Mouth sores
- Loss of appetite
- Nausea and vomiting
- Fatigue and weakness
Chemo can also affect the blood forming cells of the bone marrow, leading to:
- Increased chance of infections (due to low white blood cell counts)
- Easy bruising or bleeding (due to low blood platelet counts)
- Fatigue and weakness (due to low red blood cell counts)
Side effects usually go away over time after treatment ends and there are often ways to lessen them. For instance, drugs can be used to help prevent or reduce nausea and vomiting. If you do have side effects, be sure to ask your doctor or nurse about medicines to help reduce or manage them.
Some drugs can have other side effects. For example, cisplatin and paclitaxel can damage nerves (called neuropathy). This can sometimes lead to pain, burning or tingling sensations, sensitivity to cold or heat, or weakness in the hands and feet. Cisplatin can also affect the nerves of the ear, leading to hearing loss. In most cases these problems improve or even go away once treatment is stopped, but they may last a long time in some people. You should report this, as well as any other side effects or changes you notice while getting chemotherapy, to your medical team so that you can get prompt treatment for them. In some cases, the doses of the chemotherapy drugs may need to be reduced or treatment may need to be delayed or stopped to keep the effects from getting worse.
A drug called octreotide (Sandostatin® and Sandostatin LAR®) may also help some people with advanced thymoma. This is not a typical chemo drug. It's a man-made version of a hormone called somatostatin. The drug works in some cases because it attaches to the thymoma cells and causes them to stop growing or die. Side effects of this drug can include pain or burning at the injection site, stomach cramps, nausea, vomiting, headaches, dizziness, and fatigue. It is also linked to increased risk of gallstones.