Dr Cengiz Şen

Lung Cancer

Lung cancer is the leading cause of cancer-related death among men and women.

1,76 of 2.4 million lung cancer diagnosed people have died in 2018  Although it was very rare in the beginning of 20 th century ;lung cancer increased in numbers mostly parallel to to rapid  increase in tobacco consumption ; about %11.6 of all cancer patients are lung cancers , and lung cancer accounts for  %18.4 of all cancer related deaths.

Lung cancer is also a serious health problem in our country. Total number of lung cancer patients are 59000 , 34000 new patients in 2013 and approximately 21000 deaths annualy.

 

Risk Factors

 

  • Cigarette smoking ; most important risc factor; is responsible for 80-90% of lung cancers . Estimated risk of lung cancer in smokers compared with non smokers vary 10-30 fold. Age  at onset of smoking, duration of smoking ,cigarettes smoked per day, tar and nicotine content, unfiltered cigarettes influence the likelihood of lung cancer. Second hand smoke also have role for lung cancer .  There is 20-30%increase of developing lung cancer if you have second hand smoke exposure by living with a smoker. Quitting smoking is the single most effective prevention for lung cancer.
  • Other risk factors
    • Radiation therapy; specially for breast cancer and lymphoma
    • Living in industrial areas, cities with air pollution; exposure to environmental toxins ; asbestos ,metals(nickel, chromium arsenic) radon ,polycyclic aromatic hydrocarbons, radiation .Asbestos exposure is associated with 5 fold increase for lung cancer; smokers with asbestos exposure have higher relative risk  50-100 fold. Radon which is a radioactive gas that occurs naturally in the ground. also increases the risk of lung cancer
    • Patients with pulmonary fibrosis, have a 7 fold increased risk for lung cancer. There is also an increased risk of lung cancer  in scar tissues developed after diseases like tuberculosis compared to normal tissues.
    • Genetic factors ; Having relatives diagnosed lung cancer increases the risk of developing of lung cancer ; approximately 2.7 fold .

 

COMPLAINTS:

 

The most common symptoms are cough, dyspnea, phlegm with blood, chest pain, weight loss,  and dyspnea . Cough is present in  up to 75 % of lung cancer patients.

Symptoms may also occur due to metastasis . Severe bone pain is present in bone metastasis; Headache, seizures may happen in brain metastasis.

 

Is early diagnosis possible ?

 

Lung cancer is insidious, you may not have any complaints unless the disease is well advanced ,stage 3or stage 4 in which the treatment chance  is very low .

5 year survival rate of all lung cancer patients  is approximately 19% This is mostly due to late diagnosis. At the time of diagnosis  most of the patients have either locally advanced (stage 3) or metastatic disease (stage 4) .

On the other hand ;  according to lung cancer 8th staging system, if a cancer tissue is equal or smaller than 1 cm without lymph node involvement and  metastasis; it is classified as stage 1A1. İf you can detect the cancer at this stage and remove it by surgery; you can have a five- year survival rate of 90% (for all stage 1 cancers %73)

80% of people  diagnosed with lung cancer are 55 or older .

Chest radiograph  and sputum cytology are not recommended  for early detection (screening) and has no role for mortality reduction of  lung cancer . Clinical trials showed that screening healthy  individuals with smoking history  using low dose ct annualy increased early diagnosis rate and  decreased the mortality rate from lung cancer by 20%

 

Diagnosis

 

For the detection of lung cancer   chest x ray, computed tomography , pet-ct can be ordered to visualise the cancer tissue . Radiological findings are not sufficient for diagnosis , tissue biopsy and examination by a pathologist is warranted. A biopsy can be done by bronchoscopy , surgery, insertion a needle to remove the fluid in the lung or  insertion a needle under ct guidance to obtain  a tissue from the cancer suspected tissue.  To evaluate the extend of spread of the cancer , pet-ct and cranial mr imaging can be used.

 

Treatment  

 

Treatment of lung cancer must be carried out by  a team of specialist  including chest physician,  chest surgeon, medical oncologist, radiation oncologist,  and pathologist.

 

Early detection and complete removal of the cancer tissue is very important for treatment success.  . İf  a stage 1 lung cancer smaller than 1 cm is removed by surgery; treatment success rate is up to 90%..

Chemotherapy and radiotherapy can be applied after or before the surgery according to cancer stage or findings in the operation .

İf surgery is not an option chemotherapy and radiotherapy can be given . Specific targeted therapies (agents targeting specific molecular pathways) or immunotherapy which have less side effects  compared to standard chemotherapy  can also be be used in selected patients with certain blood test results and identification of genetic alterations (driver  mutations) in cancer tissue