Lung cancer and World No Tobacco Day

Prof Y Indibor Singh *

Lung CA seen on CXR :: Pix - Pix - Wikipedia/James Heilman, MD

Introduction: All of us know that lung cancer is very common, in fact it is the commonest cancer both in male and female in many parts of the world and so also in our state of Manipur. Radiotherapy department of RIMS gets on an average 200 new cases per year for the last 5 years making it the commonest cancer in both male and female in 2015. Lung cancer usually appears at an advanced age usually after 5th decade onwards and so is known as disease of the elderlies with a male predominance.

But of late there is age migration that is more younger persons below 50 years are affected and incidence among females is rising probably due to increase use of tobacco among females. We also know that >80% of newly diagnosed lung cancer is related with tobacco uses mainly smoking and as such is the most preventable cancer known.

Apart from tobacco other carcinogens for lung cancer are radiation exposure specially from background radon, vehicle exhaust fumes, pneumoconiosis due to asbestos and second hand smoker etc. It is also true that its fatality rate remains very high in spite of advances in early detection, awareness and advanced treatment methods.

The present survival rate of lung cancer remains dismally poor at 5 years 5%. The incidence and mortality rate are also not showing any sign of let up or downward trend. Majority >70% will come in advanced or metastatic stage which is rarely curable and as such goal of treatment is palliative or simply prolongation of survival, as far as manageable.

FAQs: Why lung cancers are detected late?

Lung cancer has no specific symptom and as such both patient and general physician or family doctors cannot detect or diagnosed it early. Besides in early stages most patients remain relatively asymptomatic. Presently there is no single standard test or tool which can diagnosed lung cancer in early curable stages that is stage I and II.

Most of the early stage diagnosis are by chance detection though in western and developed countries the diagnosis in early stage is more due to screening test in high risk category like chronic smokers. High resolution CT Scan (HRCT) is the best imaging tool for detection lung cancer but it is costly, not accessible to all and cannot be used for mass screening program and lacks sensitivity. Initially the disease mimics many simple lung infections and difficult to distinguished from TB and fungal lung infections.

To get biopsy from lung mass lesion needs skill and expertise. Simple procedures like sputum examination and bronchoscopy lavage yields very low positive results. Taking direct biopsy from mass lesions is the best procedure but is risky specially in elderly with Obstructive lung disease and deep seated lesions. Due to this most lung cancers are diagnosed late when the disease become florid and advanced and disseminated.

Types of lung cancer: Broadly primary lung cancer is grouped into two? Small cell type and Non small cell type (NSCLC). NSCLC is of 4 major sub-types viz, Squamous cell type and nonsquamous which includes adenocarcinoma, large brocho-alveolar, clear cell type and other rare types.

Now a days these types are again differentiated according to the genomic changes leading to different molecular expression which have a bearing in the pathogenesis and biological behaviour of the disease and specific therapy thereof. As a result some lung cancers are fast growing and spread rapidly and some remain confined to lung and others are slow growing. Small cell lung cancers are fast growing and also spread fast and reaching brain is > 80% and as such surgery has a limited role.

About treatment: Presently stage I and II are curable by surgery or radiation alone. The choice depends on patient preference, availability of expertise, patient's performance status and lung function and other co morbid conditions etc. However, in stage III a few are curable if it can be resected but stage IIIb without surgery is incurable.

Radiation combined with chemotherapy can control disease and prolonged survival. Stage IV is metastatic stage i,e already distant spread is there and treatment is mainly palliative or symptom amelioration. However, with the advent of targeted molecular therapy treatment of lung cancer has gone into a new direction. Personalised treatment is possible after molecular tumor marker or gene profiling test.

With effective chemo and targeted therapy combined with local radiation metastatic lung disease become a chronic manageable disease with good quality of life. Radiation treatment has advanced rapidly and newer technologies like Stereotactic body radiotherapy using cyber knife can cure early stage I and II and also treat metastatic sites to relieve symptoms and prolong survival. For advanced disease, image guided radiotherapy (IGRT) can produce better results with less side effects and cure in some cases.

The latest breakthrough in lung cancer treatment is immunotherapy. It is treatment of lung cancer by reactivating the body's defence mechanism against cancer which was made defunct by cancer. Cancer infiltrating killer lymphocyte cells are empowered to kill the lung cancer cells. Many new targeted therapy molecules are under development with active research works going on however the best strategy to combat this deadly disease will be primary prevention i,e is quitting tobacco.

Why it is hard to quit tobacco? Tobacco is one of the most addicting substance. We all know about it. Nicotine in tobacco is the one which makes you addicted. There are nicotine receptors in the neurones, in the brain and once addicted the cells can't function properly without stimulation by nicotine.

That's why it is tough to quit tobacco suddenly, the craving for next puff is always there. Nicotine don't cause cancer but along with it brings a host of carcinogenic agents both compounds and elements (about 50 or so identified). If you are a chronic or heavy user (>30 pack years) stopping tobacco suddenly will produce withdrawal syndrome and dangerous to your life. So you should take the help of a clinical psychologist for behavioural therapy and undergo Nicotine Replacement Therapy (NRT) according to the grade of severity.

It is a startling fact that only 3% are successful in quitting tobacco use with voluntary effort. That means the relapse rate is as high as 97% according to one survey from US general surgeons report. Sometimes it will take a Herculean effort to quit tobacco but it is worth trying because it is never too late. The risk of cancer development in future is reduced but never becomes zero.

Thus E- Cigarettes reduced cancer risk? The answer is probably not. Though it is designed to filter out the carcinogens with the help of an atomiser, battery powered which allow only the nicotine to reach lung, analysis in lab found trace of lethal carcinogenic elements and compounds. It may end up as giving a false sense of security or protection from developing lung cancer.

What is the role of World No tobacco day (WNTD)? WNTD celebrated every year on 31st May by WHO since 1987 is only to bring awareness and highlight the harmful effects of tobacco on health mainly cancer, respiratory diseases, cardiovascular diseases which kills more than HIV, Malaria and TB combined globally.

Various measures and strategies are initiated and global anti tobacco campaign started to control tobacco uses so that loss of lives, man days, premature death, huge financial burden on health care cost on governmentswhich negate the income from tobacco products can be mitigated.

Lastly, a message to the tobacco users smoking or smokeless or wannabe smokers : the government the law, health education and advice and counselling cannot stop you nor force you to stop from tobacco and you can always say it is my life, I want to enjoy the way I like but remember you will pay a heavy price for it later in life. Why you should shorten your life journey without any sence of fulfilment. So call it a day to tobacco from today and enjoy a fruitful beautiful life.