A brief guide to understanding lung cancer

This is the leading cause of cancer death in Canada in men and women — and one of the most difficult to treat successfully. However, medical advances are finding new weapons to fight this disease.

It’s probably no surprise to learn that smoking causes about 90 percent of all primary lung cancers, meaning those that originate in the lungs. However, this disease can also result from exposure to air pollution or industrial toxins such as asbestos or radon.

• Breathing in such poisons for years causes genetic mutations that make cells in the lungs multiply uncontrollably and form a tumour, also called a carcinoma. This can grow into nearby blood vessels and lymph nodes, then spread (metastasize) to other sites in the body, most commonly to the bones, brain and liver.
• Other types of cancer can also move into the lungs from elsewhere in the body; this is called secondary lung cancer.
• Lung tumours can grow undetected for years. Eventually, symptoms develop and may include coughing, shortness of breath, bloody sputum, chest pain, loss of appetite and recurring pneumonia.
• The two main types of lung cancer are non-small cell and small cell. Accounting for about 75 percent of the cases, non-small cell cancers are divided into three categories. Squamous cell carcinoma (or epidermoid carcinoma) usually starts in a major airway and can grow slowly or quickly. Adenocarcinoma can occur anywhere in the lung and varies in size and speed of growth. Large cell carcinoma typically is sizeable when discovered. Small cell lung cancer (also called oat cell cancer) is very aggressive and has metastasized by the time it’s diagnosed.
• Once the type of lung cancer you have is identified, its stage will be determined based on the size of the tumour, whether it has spread to any lymph nodes, or travelled to other parts of the body.
• There are four stages (I to IV) for non-small cell lung cancer, and two (limited and extensive) for small cell cancer. For both types, the earlier the stage, the better your long-term outlook.

• For early non-small cell cancer, surgery to remove the affected part of the lung.
• Radiation and/or chemo­therapy for inoperable and more advanced tumours.
• In some cases, clinical trials to test new and hopefully more effective treatments.

• Use a thoracic surgeon (one who specializes in chest procedures) if you're scheduled for surgery. One study showed that people have a much higher mortality rate when their surgery is performed by general surgeons rather than by specialists.
• Look for high volume. If you're having lung surgery, choose a hospital where many lung cancer surgeries are performed. Researchers who analyzed lung cancer patients' records from 76 hospitals found that the more lung surgeries performed at a hospital, the longer patients survived.
• Get relief from pain. If you have pain that isn't well controlled, don't hesitate to talk to your doctor about more effective painkillers. Surveys show that 42 percent of people with cancer aren't adequately treated for pain, although 95 percent could get relief.

For up-to-date information on lung cancer risk factors, research, treatments and support, contact either the Canadian Cancer Society (416-961-7223 or www.cancer.ca) or the Canadian Lung Association (613-569-6411 or www.lung.ca).

Lung cancer is a terrifying diagnosis. However, if caught early and the proper steps are taken, there are medical options you can consider. Talk with your doctor if you think you are at risk for lung cancer.