Lung Cancer
Lung Cancer
Normally, cells grow and divide to form new cells as the body needs them. When cells grow old, they die and new cells take their place. Sometimes this orderly process goes awry - that is, new cells form when the body does not need them, and old cells do not die when they should. These extra cells can form a mass of tissue, or tumour. Cancerous tumours are abnormal and divide without control or order.
The lung is the most common site for primary cancer worldwide, and smoking tobacco is the leading risk factor. The lung is also a common site of metastases for various malignancies. Metastases occur when a single tumour cell or clump of cells gain access to the blood stream or lymphatic system, travel to a new organ such as the lung, begin to multiply, and then regrow their vascular structure to obtain food.
Interventional radiologists can deliver treatments for lung cancer directly to the cancer without significant side effects or damage to nearby normal tissue. There are two main methods by which interventional radiologists can treat cancer. The first is to use the vascular system to deliver chemotherapy medicine directly to the cancer's vascular supply. This limits damage and toxicity to the rest of the body while delivering the highest dose of the chemotherapy to the cancer.
The second method interventional radiologists use to treat cancer is to "cook" or "freeze" the cancer by sticking a small, energy-delivering needle directly into the cancer that heats or freezes the cancer without significant damage to nearby normal tissue. Since these techniques are delivered at the cancer specifically, patients have fewer overall side effects making this especially useful in patients with other significant medical problems.
Lung cancer is the main cancer in the world today and is the leading cause of cancer death in Europe.
85-95% of lung cancers are smoking related.
More European people die each year from lung cancer than from breast, prostate and colorectal cancers combined.
Lung cancer kills more men than prostate cancer and more women than breast cancer.
Between 1960 and 1990, deaths from lung cancer among women increased by more than 400%.
• Coughing that doesn't go away
• Persistent chest pain
• Shortness of breath, wheezing
• Coughing up blood
• Hoarseness
• Swelling of the face and neck
• Loss of appetite and weight
• Fatigue
There are a number of tests that can help in the diagnosis of cancer, including blood tests, physical examination and a variety of imaging techniques including X-rays (e.g., chest X-rays and mammograms); computed tomography (CT). Usually, however, the final diagnosis cannot be made until a biopsy is performed. In a biopsy, a sample of tissue from the tumour or other abnormality is obtained and examined by a pathologist. By examining the biopsy sample, pathologists and other experts also can determine what kind of cancer is present and whether it is likely to be fast or slow growing. This information is important in deciding the best type of treatment. Open surgery is sometimes performed to obtain a tissue sample for biopsy. But in most cases, tissue samples can be obtained without open surgery with interventional radiology techniques.
Needle biopsy, also called image-guided biopsy, is usually performed using a moving X-ray technique (fluoroscopy) or computed tomography (CT) to guide the procedure. In many cases, needle biopsies are performed with the aid of equipment that creates a computer-generated image and allows radiologists to see an area inside the body from various angles. This "stereotactic" equipment helps them pinpoint the exact location of the abnormal tissue. Needle biopsy is typically an outpatient procedure with very infrequent complications; less than 1% of patients develop bleeding or infection. In about 90% of patients, needle biopsy provides enough tissue for the pathologist to determine the cause of the abnormality.
Advantages of needle biopsy include:
With image guidance, the abnormality can be biopsied while important nearby structures such as blood vessels and vital organs can be seen and avoided.
The patient is spared the pain, scarring and complications associated with open surgery.
Recovery times are usually shorter and patients can more quickly resume normal activities.
A similar technique called fine needle aspiration can be used to withdraw cells from a suspected cancer. It also can diagnose fluids that have collected in the body. Sometimes, these fluid collections also may be drained through a catheter, such as when pockets of infection are diagnosed.
Many interventional radiology procedures for the diagnosis and treatment of cancer can be performed on an outpatient basis or during a short hospital stay. In many cases, the procedures:
• offer new cancer treatment options
• are less painful and debilitating for patients
• result in quicker recoveries
• have fewer side effects and complications.
By the time lung cancer becomes symptomatic, 85% of patients are incurable, often due to serious coexisting health conditions or poor respiratory function. Most patients who are diagnosed with non-small cell lung cancer are not surgically resectable at the time of diagnosis. For these patients, minimally invasive interventional radiology procedures can help reduce pain and improve quality of life.
Radiofrequency ablation (RFA) offers a nonsurgical, localised treatment that kills the tumour cells with heat, while sparing nearby healthy lung tissue. Thus, this treatment is much easier on the patient than systemic therapy. Radiofrequency energy can be given without affecting the patient's overall health and most people can resume their usual activities in a few days. It is a safe, minimally invasive tool for local pulmonary tumour control with negligible mortality, little morbidity, short hospital stay, and positive gain in quality of life.
In this procedure, the interventional radiologist guides a small needle through the skin into the tumour. From the tip of the needle, radiofrequency energy (similar to microwaves) is transmitted to the tip of the needle, where it produces heat in the tissues. The dead tumour tissue shrinks and slowly forms a scar. It is ideal for nonsurgical candidates and those with smaller tumours.
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Depending on the size of the tumour, RFA can shrink or kill the tumour. Because it is a local treatment that does not harm much healthy tissue, the treatment can be repeated as often as needed to keep patients comfortable. It is a relatively safe procedure, with low complication rates.
By decreasing the size of a large mass, or treating new tumours in the lung as they arise, the pain and other debilitating symptoms caused by the tumours are often relieved. While the tumours themselves may not be painful, when they press against nerves or interfere with vital organs, they can cause pain. RFA is effective for small to medium-sized tumours and emerging new technologies should allow the treatment of larger cancers in the future. RFA is a new treatment that has shown early, promising results, but long-term studies have not yet been completed.
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RFA is most effective when all the cancer is localised in the lung.
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It can be used to treat primary lung cancer and tumours that have metastasised (spread) from other areas in the body to the lung
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Usually it does not require general anesthesia
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It is well tolerated. Most patients can resume their normal routine the next day and may feel tired for a few days.
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It can be repeated if necessary
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It may be combined with other treatment options
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It can relieve pain and suffering for many cancer patients
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It only requires a short hospital stay
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It causes few complications
New Cancer Treatments on the Horizon
Interventional radiology is playing a role in developing new techniques that may improve cancer treatment in the future, including the use of magnetic particles to draw cancer-killing agents into tumours; and the delivery of genetic material, called gene therapy, to fight or prevent cancers. These techniques are still investigational, but they offer new hope in the war against cancer.
Interventional radiologists are currently investigating a new technique in which magnets are used to pull chemotherapy drugs into tumours. Microscopic magnetic particles are attached to the cancer-killing drugs and infused through a catheter into the blood vessel that feeds the tumour. A rare earth magnet is positioned over the patient’s body directly above the site of the tumour. The magnet pulls the drug-carrying particles out of the blood vessel so that they lodge in the tumour. Although the technique is still experimental, early research is promising. Physicians are hopeful that it will bolster the effects of chemotherapy while avoiding some of the drugs’ side effects, such as hair loss and nausea.
In recent years, scientists have gained a new understanding about genes - the basic biological units of heredity - and the role they play in disease. This knowledge has set the stage for medical science to alter patients’ genetic material to fight or prevent cancer. Although the science of gene therapy is still in the early, experimental stages, researchers are hoping that in the future the therapy can be used to:
• alter the cells of a patient’s natural immune system with cancer-fighting genes and returning them to the body, where they could more forcefully attack the cancer;
• remove cancer cells from the body and alter them genetically so that the patient’s own immune system will mount a strong defence against them. In this technique, the altered cancer cells would act as a cancer vaccine;
• replace a faulty gene responsible for the growth of cancer with a “good” gene;
• inject a tumour with genes that will make it more susceptible to chemotherapy or other cancer-fighting agents; and
make bone marrow and other organs resistant to chemotherapy, so that the drugs will destroy tumours without damaging healthy tissue.
One of the challenges of gene therapy is finding safe and effective ways to deliver genes or genetically altered cells to the site of the tumour. Interventional radiologists, with their special expertise in using x-rays and other imaging techniques to guide catheters and other tools through the body are expected to play an important role in this new technology.
Treatments for Cancer Complications
There are also a number of interventional radiology techniques that are used to treat the complications of cancer, including pain, bleeding, and obstruction of vital organs, blood clots and infection. Although these treatments do not cure cancer, they can make patients more comfortable, extend life by treating serious complications and improve the quality of life for cancer patients.
Control of pain is one of the most important aspects of cancer care. Pain not only affects patients’ quality of life and ability to function; it may also lower their tolerance for needed cancer treatments.
In many cancer patients, pain results from the spread of the lung tumour into surrounding nerves and other tissues. In these cases radiofrequency thermal ablation could represent an option to reduce the pain.
A particularly painful complication of cancer is when the disease spreads (metastasises) to bones. In a technique called transcatheter embolisation, interventional radiologists inject tiny particles, the size of grains of sand, through a catheter and into the artery that supplies blood to the tumour. The particles cause clotting that decreases the tumour’s blood supply, reducing pain and decreasing the likelihood of bone fracture.
More recently, interventional radiologists can administer radiofrequency heat to “cook” and destroy the part of the bone tumour that causes pain.
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Taken from www.sirweb.org
edited by R. Lencioni
July 2005