cancer is likely to eclipse breast cancer as the leading cause of cancer mortality in Irish women in the near future

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1 Lung cancer is likely to eclipse breast cancer as the leading cause of cancer mortality in Irish women in the near future Lung cancer risk factors, presentation and diagnosis Eileen Byrne, Lung Cancer Co-ordinator, Midland Regional Hospital, Mullingar, Co Westmeath In Ireland, 2,3 people die from lung cancer each year. 1 This equates to approximately per cent of all cancer deaths. Incidence in Irish men has fallen slightly in recent years and is below the EU average. However, in Irish women, lung cancer is on the increase. Lung cancer is likely to eclipse breast cancer as the leading cause of cancer mortality in Irish women in the near future and has already done so in some countries. 3 Despite the enormous burden of disease, the prevailing attitude to lung cancer, even among healthcare professionals, is one of pessimism, or at worst, absolute nihilism. This reflects poor overall survival rates, even in the minority of patients who present with apparent early-stage disease who are treated with intention to cure. Overall five-year survival is less than 1 per cent and, despite advances in radiotherapy and chemotherapy, surgery remains the only effective curative treatment for lung cancer. Risk factors Smoking The incidence of lung cancer is strongly correlated with cigarette smoking, with about 9 per cent of lung cancers arising as a result of tobacco use. The risk of lung cancer increases with the number of cigarettes smoked over time. This risk is referred to in terms of pack-years of smoking history (i.e. the number of packs of cigarettes smoked per day multiplied by the number of years smoked, a pack being a pack of cigarettes). For example, a person who has smoked two packs of cigarettes per day for 1 years has a pack-year smoking history. While the risk of lung cancer is increased with even a 1-pack-year smoking history, those with 3-pack-year histories or more are considered to have the greatest risk for the development of lung cancer. Pipe and cigar smoking can also cause lung cancer, although the risk is not as high as with cigarette smoking. 22

2 The risk of developing lung cancer decreases each year following smoking cessation as normal cells grow and replace damaged cells in the lung. In former smokers, the risk of developing lung cancer begins to approach that of a nonsmoker about 15 years after cessation of smoking. Passive smoking Passive smoking is an established risk factor for the development of lung cancer. Asbestos fibres Asbestos fibres are silicate fibres that can persist for a lifetime in lung tissue following exposure to asbestos. The workplace is a common source of exposure to asbestos fibres, as asbestos was widely used in the past as both thermal and acoustic insulation. Today, asbestos use is limited or banned in many countries, including Ireland. Both lung cancer and mesothelioma (cancer of the pleura of the lung as well as the peritoneum) are associated with exposure to asbestos. Cigarette smoking drastically increases the chance of developing an asbestos-related lung cancer in exposed workers. Radon gas Radon gas is a natural, chemically-inert gas that is a natural decay product of uranium. Uranium decays to form products, including radon, which emit a type of ionizing radiation. As with asbestos exposure, concomitant smoking greatly increases the risk of lung cancer with radon exposure. Radon gas can travel up through soil and enter homes through gaps in the foundation, pipes, drains or other openings. Despite the fact that radon gas is invisible and odourless, it can be detected with simple test kits. Lung diseases The presence of certain diseases of the lung, notably chronic obstructive pulmonary disease (COPD), is associated with an increased risk for the development of lung cancer, even after the effects of concomitant cigarette smoking have been excluded. Prior history of lung/other cancer Survivors of lung/other cancer have a greater risk than the general population of developing lung cancer. Types of lung cancer Most lung cancers can be divided into two main types: nonsmall cell lung cancer (NSCLC) and small cell lung cancer (SCLC). The types behave in different ways and have their own special treatment needs. NSCLC subtypes Squamous cell carcinoma These cells are usually found in the centre of the lungs, lining the bronchi, and do not spread quickly. This is the most common type of lung cancer in Ireland. Adenocarcinoma These cells are usually found at the edges of the lung where mucus is made. Large cell carcinoma These are large, round cells that may appear in any part of the lung and tend to spread quickly. SCLC These cancers have small round cells that tend to grow quickly. They form large tumours and spread to lymph nodes and other organs such as the brain, bones, adrenal glands and the liver. This type of cancer often starts in the bronchi near the centre of the chest. Other types of lung cancer A rare type of lung cancer is mesothelioma which is a cancer of the pleura cells. Usually it occurs after someone has been exposed to asbestos. Signs and symptoms of lung cancer Symptoms of lung cancer are varied and depend on where and how widespread the tumour is. Warning signs of lung cancer are not always present or easy to identify. No symptoms In up to 25 per cent of people who get lung cancer, the cancer is first discovered incidentally on a routine chest x-ray or computed tomography (CT) scan as a solitary small mass. These patients with small, single masses often report no symptoms at the time the cancer is discovered. Figure 1. Anatomy of the lungs. Symptoms related to the cancer The growth of the cancer and invasion of lung tissues and surrounding tissue may interfere with breathing, leading to symptoms such as cough, shortness of breath, wheezing, chest pain and haemoptysis. If the cancer has invaded nerves, for example, it may cause shoulder pain that travels down the outside of the arm (called Pancoast s syndrome) or paralysis of the vocal cords, leading to hoarseness. Invasion of the oesophagus may lead to dysphagia. If a large airway is obstructed, the collapse of a portion of the lung may occur and cause infections (abscesses, pneumonia) in the obstructed area. Chest infections, especially in patients with a smoking history, which do not resolve with treatment should be investigated. Symptoms related to metastasis Lung cancer that has spread to the bones may produce excruciating pain at the sites of bone involvement. Cancer that has spread to the brain may cause a number of neurological symptoms that may include blurred vision, headaches, seizures or symptoms, such as weakness or loss of sensation in parts of the body. 23

3 Paraneoplastic symptoms Lung cancers frequently are accompanied by symptoms that result from the production of hormone-like substances by the tumour cells. These paraneoplastic symptoms occur most commonly with SCLC but may be seen with any tumour type. A common paraneoplastic syndrome associated with SCLC is the production of a hormone called adrenocorticotrophic hormone (ACTH) by the cancer cells, leading to oversecretion of the hormone cortisol by the adrenal glands (Cushing s syndrome). The most frequent paraneoplastic syndrome seen with NSCLC is the production of a substance similar to parathyroid hormone, resulting in elevated levels of calcium in the bloodstream. Non-specific symptoms Non-specific symptoms seen with many cancers, including lung cancers, include weight loss, weakness and fatigue. Psychological symptoms, such as depression and mood changes, are also common. Warning signs of lung cancer are not always present or easy to identify. Indications for immediate chest x-ray Rapid access to appropriate multidisciplinary care improves the outcome in lung cancer. For GPs, where there is a genuine clinical suspicion, a chest x-ray should be available at their local hospital within one week and preferably on a walk-in basis. Indications for urgent/immediate chest x-ray in the over- -year age group, particularly smokers/ex-smokers, are shown in Table 1. How is lung cancer diagnosed? History and physical examination may reveal the presence of symptoms or signs that are suspicious for lung cancer. In addition to asking about symptoms and risk factors for cancer development, such as smoking, signs including breathing difficulties, airway obstruction or infections in the lungs may be detected. Cyanosis suggests a compromised function of the lung and, likewise, changes in the tissue of the nail beds, known as clubbing, may also indicate lung disease. Chest x-ray The chest x-ray is the most common first diagnostic step when any new symptoms of lung cancer are present. Chest x-rays may reveal suspicious areas in the lungs but are unable to determine if these areas are cancerous. CT scan A CT scan of the chest may be ordered when x-rays do not show an abnormality or do not yield sufficient information about the extent or location of a tumour. CT scanning of the abdomen may identify metastatic cancer in the liver or adrenal glands and a CT scan of the head may be ordered to reveal the presence and extent of metastases in the brain. Positron emission tomography Positron emission tomography (PET) scanning is a specialised imaging technique that uses short-lived radioactive drugs to produce three-dimensional coloured images of those substances in the tissues within the body. While CT scans look at anatomical structures, PET scans measure metabolic activity and functioning of tissue. PET scans can determine whether a tumour tissue is actively growing and can aid in determining the type of cells within a particular tumour. In PET scanning, the patient receives a short half-lived radioactive drug and receives approximately the amount of radiation exposure as two chest x-rays. The drug discharges particles known as positrons from wherever they are taken up and used in the body. As the positrons encounter electrons within the body, a reaction producing gamma rays occurs. A scanner records these gamma rays and maps the area where the radioactive drug is located. For example, combining glucose (a common energy source in the body) with a radioactive substance will show where glucose is rapidly being used, for example, in a growing tumour. Bronchoscopy Examination of the airways by bronchoscopy may reveal areas of tumour that can be biopsied. A tumour in the central areas of the lung or arising from the larger airways is accessible to sampling using this technique. Bronchoscopy may be performed using a rigid or a flexible fibre-optic bronchoscope and can be performed in a same-day outpatient bronchoscopy suite or an operating room. Some patients may cough up darkbrown blood for one to two days after the procedure. More serious but rare complications include a greater amount of bleeding, decreased levels of oxygen in the blood and heart arrhythmias as well as complications from sedative medications and anaesthesia. Figure 2. Clubbing. Fine needle aspiration Fine needle aspiration through the skin is most commonly performed with radiological imaging for guidance. Needle biopsies are particularly useful when the lung tumour is peripherally located in the lung and not accessible to sampling by bronchoscopy. A small amount of local anaesthetic is given prior to insertion of a thin needle through the chest wall into the abnormal area in the lung. A small risk (three to five per cent) of a pneumothorax accompanies the procedure. 24

4 Danone Actimel, an ally for the elderly in winter * Age-related immunoscenescence As we get older, the immune systems ability to react & adapt declines due to an age-related phenomenon in the body s defences called immunoscenescence. This involves both the host s capacity to respond to infections and the development of long-term immune memory, especially by vaccination. NEW NEWS How can Actimel help? Actimel is a food product scientifi cally proven in 24 published clinical trials to help strengthen your natural defences. New research suggests that probiotics can also exert a benefi cial effect not only within the gastrointestinal tract but more widely within the immune system. Effect after seasonal flu vaccination Emerging evidence suggests that Actimel (2xml) improves the immune response to seasonal fl u vaccination in the elderly. Placebo controlled studies showed 1 ; Higher antibody titres to seasonal fl u strains H1N1**, H3N2 and B in the Actimel group compared to the control and remained higher at 9 weeks after vaccination. Effect maintained on seroconversion for B strain over time under Actimel consumption at 3, 6 and 9 weeks post vaccination. A. B. H1N1 1 8 Antibody titre at 3, 6 and 9 weeks after vaccination. Boge T. et al 9. H3N2 1 8 C. 1 8 Vaxigrip, Sanofi-Pasteur MSD, season 6-7 A/New Caledonia//99 (H1N1) / A/Wisconsin/67/5 (H3N2) B/Malaysia/256/4. B Actimel Control These results are further evidence that Actimel has a measurable impact on the immune system. Further research is needed to understand the benefi ts of probiotic for different applications, in particular for how probiotics could help improve the immune response to vaccination. For more information on probiotics and Actimel, please visit * Actimel is scientifically proven to help strengthen the natural defences when consumed daily as part of a healthy diet & lifestyle. Studies on Actimel collectively demonstrate that L. casei Imunitass survives in the gastrointestinal tract and exerts a beneficial effect on each of the 3 lines of natural defence (1)The intestinal flora, (2)The intestinal mucosa and (3)The intestinal immune system or gut-associated lymphoid tissue (GALT) when consumed daily as part of a healthy diet & lifestyle. ** This is a seasonal H1N1 strain not the swine flu strain. 1 Boge T, et al. A probiotic fermented dairy drink improves antibody response to influenza vaccination in the elderly in two randomised controlled trials. Vaccine (9),doi:1.116/j.vaccine

5 Table 1. Urgent referrals for chest X ray for suspected lung cancer. 2 Patient presents with Symptoms Haemoptysis New onset unexplained cough or alteration in character of chronic cough Hoarseness Unexplained persistent chest and/or shoulder pain Dyspnoea Weight loss Features suggestive of metastasis from lung cancer (e.g. brain, bone, liver or skin) Unresolved chest infection Signs Clubbing Chest signs Hepatomegaly Cervical and/or supraclavicular lymphadenopathy Stridor Superior vena caval obstruction SVOC symptoms and signs Sensation of fullness in the face when patient bends over Breathlessness Headaches, which worsen on leaning forward or bending over Facial swelling, with a dark red look to the complexion Swollen neck Swollen arms and hands Visible swollen blue veins on the chest Dizziness Chest X ray. Report should be back in 1 week Normal chest X ray but high suspicion of cancer Suggestive of lung cancer; e.g.: Slowly resolving consolidation Pleural effusion Mass Urgent referral Immediate referral Adapted from the National Institute for Clinical Excellence, Guideline 24: Lung Cancer, 5. Thoracentesis Sometimes lung cancers involve the pleura and lead to a pleural effusion. Aspiration of a sample of this fluid with a thin needle (thoracentesis) may reveal the cancer cells and establish the diagnosis. As with the needle biopsy, a small risk of a pneumothorax is associated with this procedure. Major surgical procedures If none of the aforementioned methods yield a diagnosis, surgical methods must be employed to obtain tissue for diagnosis. These can include mediastinoscopy (examining the chest cavity between the lungs through a surgically-inserted probe with biopsy of masses or lymph nodes that may contain metastases) or thoracotomy (surgical opening of the chest wall for the removal or biopsy of a tumour). With a thoracotomy, it is rare to be able to completely remove a lung cancer, and both mediastinoscopy and thoracotomy carry the risks of major surgical procedures (complications such as bleeding, infection and risks from anaesthesia and medications). While routine blood tests alone cannot diagnose lung cancer, they may reveal biochemical or metabolic abnormalities in the body that accompany cancer. For example, elevated levels of calcium or of the enzyme alkaline, phosphatase, may accompany cancer that is metastatic to the bones. Likewise, elevated levels of certain enzymes normally present within liver cells, including aspartate aminotransferase and alanine aminotransferase, signal liver damage, possibly through the presence of a metastatic tumour. Conclusion The best strategy for combating lung cancer remains prevention. Eradication of smoking in the population has the greatest potential for reducing the risk of lung cancer; however, this task requires the commitment of several organisations including the Government, education professionals and healthcare professionals. References 1. Donnelly DW, Gavin AT, Comber H. Cancer in Ireland : a comprehensive report. Northern Ireland Cancer Registry/National Cancer Registry of Ireland, Ireland, National Institute for Clinical Excellence. Lung cancer: the diagnosis and treatment of lung cancer. National Institute for Clinical Excellence, London, O Connell F et al. Guidelines for clinical management of lung cancer. Irish Medical Journal 4; 97 (2): supplement. 26