When a person has been diagnosed with lung cancer, they must undergo cancer treatments such as chemotherapy, radiation therapy, surgery or the use of other drugs, alone or in combination. These are standard anti-cancer treatments for any type of cancer, and the therapy given is determined by the stage of the cancer, or how far the cancer has spread, and whether or not a tumor can be removed surgically.
Of the two types of lung cancer, non-small cell lung cancer is more likely to be operable than small cell lung cancer. Small cell lung cancer is the more aggressive of the two types of lung cancer, and in many cases it has already spread beyond the lungs by the time of diagnosis. With non-small cell lung cancer, there is a greater chance that the cancer will be caught in the early stages and the cancerous tumor may be able to be removed from the lung. The goal of cancer removal surgery is to remove all of the tumor and as little healthy tissue as possible. In most cases, only a section of lung tissue will have to be removed to remove the tumor, and this is called a wedge resection or segmental resection depending on the size of the lung tissue removed. In some cases, a lung lobe or a whole lung may have to be removed to remove the cancer. Removing a lobe is called a lobectomy, and removing a whole lung is called a pneumectomy. You can survive with one functioning lung, but breathing capacity is diminished with one lung, so the patient may have to have supporting therapy to improve this.
Chemotherapy is used to kill cancer cells and slow down the growth of tumors. It is very effective at this, but it also has an effect on healthy cells, so it causes a variety of side effects from skin and hair thinning to nausea and indigestion. Sometimes a single chemotherapy drug is given, and sometimes a combination of drugs is used. The drugs can be administered orally or intravenously into a vein in the arm. Chemotherapy is used after surgery to prevent regrowth of tumors and spread of cancer cells, and it is also used in cases where surgery is not an option.
Radiation therapy is another treatment used to kill cancer cells. Radiation also has a negative effect on normal cells, but a worse effect on cancer cells because they divide so rapidly and uncontrollably. The radiation is targeted as much as possible so that side effects are diminished. Radiation therapy can be administered in several different ways, including from the outside of the body, through implants placed surgically near the cancer and through radioactive implants that are injected near the site of the tumor. Sometimes, radiation therapy and chemotherapy are given in combination, especially in aggressively growing cancers like small cell lung cancer.
Although chemotherapy and radiation therapy are very effective, they have lots of side effects because they affect both cancer cells and healthy cells. Cancer researchers have a focus on developing drugs that target abnormalities of cancer cells that only occur in cancer cells and not healthy cells, so that side effects of cancer therapy on healthy cells are reduced. Some of these targeted anti-lung cancer drugs are used for treating lung cancer today, and others are in development in clinical trials. A drug called bevacizumab stops the process of angiogenesis, the process by which a tumor forms new blood vessels. This makes it less likely that the cancer will grow and spread. Erlotinib slows down the replication of non-small cell lung cancer cells, but it is generally used in cases in which the cancer has not responded to chemotherapy. Crizotinib is a drug that targets a specific type of non-small cell lung cancer that has a specific mutation; a lab test can see if your cancer cells will respond to this drug. These drugs have more specific applications than chemotherapy and radiation, and they are not effective on everyone who has lung cancer. Additionally, they still cause side effects.
For non-small cell lung cancer, stage I cancer that has not spread beyond the lung may be treated with surgery alone, or surgery and chemotherapy. Stage II lung cancer is usually treated with surgery, chemotherapy and radiation treatments. Stage III is likely to be inoperable, but surgery may be helpful in some cases. Chemotherapy and radiation are used. Stage IV cancer is treated with chemotherapy and targeted drugs, and these patients may be given the option to enlist in clinical trials to test out new drugs.
The treatment options recommended for small cell lung cancer are a little different. Stage I cancer may or may not be treated with surgery, but chemotherapy and radiation are used because small cell lung cancer is aggressive. Stages II and III are both treated with chemotherapy and radiation therapy. Stage IV small cell lung cancer is treated with chemotherapy. Patients with small cell lung cancer stages III and IV may be given the chance to enlist in clinical trials to test new anti-cancer drugs.