According to the World Cancer Research Fund (and many other reputable sources), lung cancer is the most common type of cancer worldwide, contributing 13% of the total number of cancer cases in 2012.
Lung cancer is a difficult and problematic cancer, as it develops close to a network of blood vessels and lymphatic channels – making it easier to spread to other organs, termed metastasis or metastatic cancer. The lungs are also a common organ to which other cancer types spread (for example, prostate cancer); these metastatic tumours are not lung cancer.
There are two main types of lung cancer: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC).
‘Small cell lung cancer develops and spreads at a faster rate to other parts of the body. However, SCLC responds better to chemotherapy. Following a comprehensive review of all diagnostic test results, staging of lung cancer (determining its extent and spread) with further techniques facilitates the protocol of lung cancer treatment (http://www.hmcisrael.com/oncology/lung-cancer-treatment-israel)
NSCLC accounts for approximately 85% of lung cancers, and subtypes include adenocarcinoma, squamous cell carcinoma and large lung cell carcinoma. Other (rare) types of lung cancer are carcinoid tumours and lymphomas. People between the ages of 60-80 are mainly affected (mainly men), but there are rare cases of younger people developing lung cancer.
Smoking (including pipe smoking and cigars) accounts for a vast majority of all types of lung cancers, a staggering 85%. Other causes of lung cancer include passive smoking; air pollution; radon; occupational hazards – for example, asbestos exposure (also results in mesothelioma, a type of cancer affecting the lining of the lungs) and other lung diseases (tuberculosis and chronic obstructive pulmonary disease). Avoiding or if possible eliminating these risk factors can prevent lung cancer in most cases.
How to Prevent Lung Cancer – Know The Signs and Symptoms
Symptoms are often mistaken for other conditions like bronchitis, for example. It is important to consult with a doctor if you experience any unusual or worrying symptoms. Lung cancer signs and symptoms can develop over the years, usually pronounced in the late stages of the disease’s progression.
Symptoms of lung cancer include:
1. Persistent, worsening cough
2. Breathlessness
3. Chest pain breathing, laughing or coughing – dull and persistent
4. Wheezing (or hoarseness)
5. Coughing up mucus or phlegm tinged with blood
6. Repetitive respiratory infections (for example, pneumonia)
Lung cancer that has spread to other organs (mainly liver, brain, bones and adrenal glands) also has varying symptoms, which depends on the location and size of the tumour. Symptoms include:
1. Loss of weight and appetite
2. Swelling of the neck or face
3. Blood clots
4. Jaundice (yellowing of skin and whites of your eyes)
5. Bone pain – spine pain
6. Nerve or brain damage – seizures, affected speech, memory, walking etc.
Other signs of cancer (unrelated to metastases), but the tumor itself can include low potassium and sodium levels, high calcium, increased risk of blood clots and more.
Diagnosis of Lung Cancer
Early detection of lung cancer can halve the number of mortalities, and a patient’s 5-year survival rate (free from developing cancer in the next 5 years). Lung cancer is difficult to treat when metastases (cancer spread to other organs) has occurred, as patients have a significantly lower 5-year survival rate (less than 5%). Thus, early diagnosis influences treatment, as well as a patient’s 5-year survival rate. SCLC are often diagnosed in the late stage of disease.
A comprehensive evaluation is carried out by a specialist, including chest X-rays. Chest x-rays are not conclusive as 20% of lung cancers can go undetected and abnormalities can be due to calcium deposits. Sputum cytology is another technique to evaluate (with the use of microscopy) whether there are abnormal cells within a sample of sputum (mucus) coughed up. Further diagnostics are performed, such as:
CT/ MRI scan, PET scan, Biopsy – if the above diagnostic tests indicate an abnormality, and Bronchoscopy – endoscopy of the lungs.
Lung Cancer Treatment
Non-small cell lung cancer tends to develop at a slower rate than small-cell lung cancer; NSCLC can thus be diagnosed and treated at the stage where surgical intervention is possible. Small cell lung cancer develops and spreads at a faster rate to other parts of the body. However, SCLC responds better to chemotherapy. Following a comprehensive review of all diagnostic test results, staging of lung cancer (determining its extent and spread) with further techniques facilitates the protocol of lung cancer treatment. This includes:
1. Surgery
2. Radiotherapy
3. Chemotherapy
4. Targeted therapy
5. Stereotactic radio-surgery or whole brain radiation therapy (for metastases of the brain)
Treatment involves neoadjuvant therapy (treatment prior to the main type of treatment) and adjuvant therapy (treatment following the primary treatment to minimise recurrence of lung cancer). Newer treatments continue to evolve and improve; patients also have the option to participate in clinical trials, all of which contribute to a greater chance of success in prognoses.
Contributed by Herzliya Medical Center Israel (http://www.hmcisrael.com/)
