The CyberKnife System is not a surgical procedure. In fact, there is no cutting involved. Instead, the CyberKnife System delivers high doses of radiation directly to lung tumors. The CyberKnife System offers patients who cannot undergo lung cancer surgery due to their poor medical condition, or who refuse surgery, a minimally invasive alternative treatment for lung cancer.
CyberKnife lung cancer treatments are typically performed on an outpatient basis with three to five treatments, requiring no overnight hospital stays. Most patients experience minimal to no side effects with a quick recovery time.
Lung cancer is the abnormal growth of cells in the lung resulting in a lung tumor. If the abnormal cells originated as lung cancer cells, the resulting collection of cells is called a primary lung tumor. If the abnormal cells originated in another part of the body, such as the colon or liver, and were carried to the lungs by the blood or other bodily fluids, then it is considered a metastatic lung tumor.
More than 215,000 cases of primary lung cancer cases are expected to be diagnosed in the United States in 2008. Lung cancer is the leading cause of cancer death in both men and women, and is expected to result in approximately 161,840 deaths – or about 29% of all cancer deaths – in the U.S. this year. About 13% of primary lung tumors are considered small cell, including oat cell cancer, mixed small cell/large cell carcinoma and combined small cell carcinoma. The remaining 87% of lung tumors are classified as non-small cell, which include squamous cell carcinoma, large cell carcinoma and adenocarcinoma.
Lung cancer treatment depends on the type and the stage of cancer. Lung cancer can be treated with surgery, chemotherapy and radiation; and these are often combined to offer the most effective treatment. Options for treating a metastatic tumor depend on the stage of the primary cancer. The various lung cancer treatments are described in detail below.
Find out why Dorothy, a patient at NCH, chose CyberKnife Radiosurgery for her lung cancer treatment.
Radiosurgery devices, such as the CyberKnife Robotic Radiosurgery System, offer patients a new option for the treatment of lung cancer. The CyberKnife® System is used to treat lung cancer patients who cannot tolerate surgery, have an inoperable tumor, or are seeking an alternative to surgery. The challenge that doctors face with tumors in the lung is that those tumors move as the patient breathes. Unlike traditional radiation therapy, the CyberKnife System precisely identifies the tumor location as the patient breathes normally during treatment and can be used, in some cases, to treat lung tumors non-invasively.
Surgery or surgical resection is often used to remove a tumor. For early stage lung cancer, the preferred treatment for otherwise healthy patients is a lobectomy, in which the surgeon removes a lobe of the lung. Lobectomies can be performed in two ways. One method is called a thoracotomy, in which the ribs are cut and spread to allow the surgeon to access the lobe of lung that needs to be removed. The second type of lobectomy is less invasive and done using video-assisted thorocoscopic surgery (VATS). During this procedure, small incisions are made and a camera is placed in the chest to guide the surgeon performing the surgery. Some patients with early stage lung cancer may not require that an entire lobe be removed. This procedure is called a wedge resection or segmentectomy, and can reduce the amount of normal lung tissue removed.
To be effective as possible, lung cancer surgery must not only remove the visible tumor, but eliminate any microscopic traces of the disease that remain in the surrounding tissue. Studies comparing lobectomies to wedge resections have shown that the lobectomy results in better survival rates and is more effective in removing all of a patient’s disease.
For those patients whose primary lung cancer is more advanced, as well as those who have large tumors or multiple metastatic tumors that cannot be removed by lobectomy or segmentectomy, more extensive surgery is required. In these cases, surgeons may perform a pneumonectomy, during which the entire lung is removed.
Although surgery is effective for some stages of lung cancer, patients can experience significant risk of complications, including infection, bleeding, and respiratory and cardiac problems. These complications can also lead to loss of lung function and/or a decreased quality of life.3 Open lobectomy and video assisted thorascopic surgery have local control rates and 5-year survival rates of 60-80%.
Lung cancer surgery is typically used alone for patients with very small tumors and early-stage lung cancer. However, some patients may not be well enough to undergo surgery because they suffer from other cardiac or breathing problems. For later stages of lung cancer, typically stage II and higher, surgery is often combined with chemotherapy and, perhaps, radiation therapy.
Conventional radiation therapy, called external beam radiation therapy, typically involves delivery of wide beams of radiation that encompass both the tumor and a certain amount of surrounding healthy tissue. This radiation is usually delivered in smaller doses in 25-35 sessions. Tumors within the chest do move as the patient breathes so it is necessary to irradiate a larger volume then that of the CyberKnife.
Chemotherapy is used when cancer cells are thought to be located throughout the body or they are present in a patient’s blood or other fluids, which is often the case with metastatic lung tumors and advanced-stage lung cancer. Chemotherapy medication is delivered orally or through an IV (into a vein), and is given to a patient either as the sole treatment or in combination with surgery or radiation. Chemotherapy affects both normal tissue and the cancer cells, so patients may experience side effects, such as severe nausea and vomiting, infections, fatigue and weight loss. Based on randomized clinical trials chemotherapy is recommended in addition to local treatment for patients with later-stage disease. Disease-free 5-year survival for patients treated with chemotherapy following surgery range from 48-89% depending on how advanced the disease is.