Chemotherapy (chemo) is treatment with anti-cancer drugs that may be injected into a vein or taken by mouth. These drugs travel through the bloodstream and reach most parts of the body.
When is chemotherapy used?
Chemo is typically part of the treatment for small cell lung cancer (SCLC). This is because SCLC has usually already spread by the time it is found , so other treatments such as surgery or radiation therapy would not reach all areas of cancer.
- For people with limited stage SCLC, chemo is often given with radiation therapy. This is known as chemoradiation.
- For people with extensive stage SCLC, chemo with or without immunotherapy is usually the main treatment. Sometimes radiation therapy is given as well.
Some patients in poor health might not be able to tolerate intense doses of chemo or a combination of drugs. But older age by itself is not a reason to avoid chemo.
Chemo drugs used to treat SCLC
Generally, SCLC is treated with combinations of chemo drugs. The combinations used most often are:
- Cisplatin and etoposide
- Carboplatin and etoposide
- Cisplatin and irinotecan
- Carboplatin and irinotecan
Topotecan and lurbinectedin (Zepzelca) are chemo drugs that might be used by themselves in people with SCLC that has spread, especially if they have already tried cisplatin or carboplatin.
How is chemotherapy given?
Chemo drugs for lung cancer are typically given into a vein (IV), either as an injection over a few minutes or as an infusion over a longer period of time. This can be done in a doctor’s office, chemotherapy clinic, or in a hospital setting.
Often, slightly larger and sturdier IVs known as central venous catheters (CVCs), central venous access devices (CVADs), or central lines are needed to give chemo. They are used to put medicines, blood products, nutrients, or fluids right into your blood. They can also be used to take out blood for testing. Many different kinds of CVCs are available. The most common types are the port and the PICC line.
Doctors give chemo in cycles, with each period of treatment followed by a rest period to give you time to recover from the effects of the drugs. Cycles are most often 3 or 4 weeks long, and initial treatment is typically 4 to 6 cycles. The schedule varies depending on the drugs used. For example, some drugs are given only on the first day of the chemo cycle. Others are given for a few days in a row, or once a week. Then, at the end of the cycle, the chemo schedule repeats to start the next cycle.
For advanced cancers, the initial chemo combination is often given for 4 to 6 cycles, sometimes in combination with an immunotherapy drug. Beyond this, doctors might also recommend extending treatment with a single immunotherapy drug, for people who have had a good response to their initial chemotherapy or have had no worsening of their cancer.
If the cancer progresses (gets worse) during treatment or returns after treatment is finished, other chemo drugs may be tried. The choice of drugs depends to some extent on how soon the cancer begins to grow again. (The longer it takes for the cancer to return, the more likely it is to respond to further treatment.)
- If cancer returns more than 6 months after treatment, it might respond again to the same chemo drugs that were given the first time.
- If the cancer comes back sooner, or if it keeps growing during treatment, further treatment with the same drugs isn’t likely to be helpful. If further chemo is given, most doctors prefer treatment with a single, different drug to help limit side effects. Topotecan and lurbinectedin are most often used, although other drugs might also be tried.
SCLC that progresses or comes back can be hard to treat, so taking part in a clinical trial of newer treatments might be a good option for some people.
Possible side effects of chemotherapy for SCLC
Chemo drugs can cause side effects. These depend on the type and dose of drugs given and how long they are taken. Some common side effects of chemo include:
- Hair loss
- Mouth sores
- Loss of appetite or weight changes
- Nausea and vomiting
- Diarrhea or constipation
Chemo can also affect the blood-forming cells of the bone marrow, which can lead to:
- Increased chance of infections (from low white blood cell counts)
- Easy bruising or bleeding (from low blood platelet counts)
- Fatigue (from low red blood cell counts)
These side effects usually go away after treatment, but there are also often ways to lessen them. For example:
- Drugs can be given to help prevent or reduce nausea and vomiting.
- Drugs can be used to help prevent or treat low blood cell counts (especially low white blood cell counts). Trilaciclib (Cosela) is one example, although other drugs known as growth factors can be used as well.
Some drugs can have specific side effects. For example:
- Drugs such as cisplatin and carboplatin can damage nerve endings. This is called peripheral neuropathy. It can sometimes lead to symptoms (mainly in the hands and feet) such as pain, burning or tingling sensations, sensitivity to cold or heat, or weakness. In most people this goes away or gets better after treatment is stopped, but it may last a long time in some people.
- Cisplatin can also cause kidney damage. To help prevent this, doctors give lots of IV fluids before and after each dose of the drug is given.
Be sure to report any side effects you notice during chemo to your medical team so that they can be treated promptly. In some cases, the doses of the chemo drugs may need to be reduced or treatment may need to be delayed or stopped to prevent the effects from getting worse.