LUNG CANCER

  • Second most common cancer
  • Leading cause of cancer death. About 1 out of 4 cancer deaths are because of lung cancer
  • Despite poor prognosis, lung cancer is curable in early stages.
  • Two main types:
    -Non-small cell lung cancer: 85-90%
    -Small cell lung cancer: 10-15%

Risk Factors:

  • Tobacco smoking:
    - Smokers have 20 fold increase of lung cancer compared to non smokers
    - Tobacco smoke contain thousands of chemicals which include >70 chemicals are proven carcinogens
    - Quitting smoking is beneficial. Former smokers are at 9 fold increased risk while current smokers are at 20 fold increased risk of lung cancer  compared to non smokers.
    - Environmental tobacco smoke exposure to non smokers through passive smoking from smokers also increase the risk

  • Asbestos and other chemical carcinogens
  • Radiation exposure
  • Environmental pollution 

Screening for Lung Cancer:

  • Age group 55-80 yrs with a history of smoking
  • United States Preventive Services Task Force (USPSTF) recommend annual screening for lung cancer with low dose computed tomography in adults aged 55-80 years who have a 30 pack year smoking history and currently smoke or have quit within past 15 years. Screening should be discontinued once a person has not smoked for 15 years or develops a health problem that substantially limits life expectancy or the ability or willingness to have curative lung surgery.

Alarming signs of carcinoma lung:

  • Cough that is persistent or gets worse
  • Chest pain that is often worse with deep breathing, coughing, or laughing
  • Hoarseness of voice
  • Coughing out blood or rust-colored sputum (spit or phlegm)
  • Breathlessness
  • Infections such as bronchitis and pneumonia that don’t go away or keep coming back
  • New onset of wheezing
  • If lung cancer spreads to distant organs, it may cause Bone pain, headache/ seizures, jaundice

Treatment for lung cancer:

Multidisciplinary management involving surgical oncologist, medical oncologist and radiation oncologist improves treatment planning and better cure.

Non small cell Lung Cancer:

  • Surgery: Surgical resection play pivotal role in management of early stage cancer. Complete resection (Lobectomy/Pneumonetomy), systemic mediastinal lymph node dissection in suitable candidates is fundamental of surgical management. 
    Videoassisted thoracic surgery is now done in many centres for early stage ling cancer because of associated low morbidity rate.

    Surgery for lung cancer is a major operation and can have serious side effects, which is why surgery isn’t a good idea for everyone. While all surgeries carry some risks, these depend to some degree on the extent of the surgery and the person’s health beforehand. 

    Possible complications during and soon after surgery can include reactions to anesthesia, excess bleeding, blood clots in    the legs or lungs, wound infections, and pneumonia. While it is rare, some people may not survive the surgery.
  • Chemotherapy: Depending on the stage, chemotherapy may be used as
       - Before surgery (sometimes along with radiation therapy) known as neoadjuvant therapy.
       - After surgery (sometimes along with radiation therapy) known as adjuvant therapy.
       - Along with radiation therapy (concurrent therapy) for some cancers that can’t be removed by surgery because the cancer has grown into nearby important structures
       - As the main treatment (sometimes along with radiation therapy) for more advanced cancers or for some people who              aren’t healthy enough for surgery.

  • Radiation Therapy: Depending on the stage radiation therapy might be used as:
    - As the main treatment (sometimes along with chemotherapy), especially if the lung tumor can’t be removed because of its size or location or person isn’t healthy enough for surgery, or doesn’t want surgery.
    - After surgery (alone or along with chemotherapy)
    - Before surgery (usually along with chemotherapy) to try to shrink a lung tumor to make it easier to operate on.
    - To relieve (palliate) symptoms of advanced NSCLC such as pain, bleeding, trouble swallowing, cough, or problems caused by spread to other organs such as the brain.

  • Targetted therapy:  eg Gefinib, erlotinib, crizotinib
    They sometimes work when chemo drugs don’t, and they often have different (and less severe) side effects. At this time, they are most often used for advanced lung cancers, either along with chemo or by themselves.

Small Cell Lung Cancer:

Very aggressive cancer and spread very fast, so only rarely very early stage is detected for which sugery can be planned. Most patients are treated with chemotherapy or radiation therapy or both.

Prognosis: for non small cell lung cancer

                                                Stage                                                            5 year survival

                                                    I                                                                        45-50%

                                                    II                                                                       30-35%

                                                    III                                                                      10-15%

                                                    IV                                                                         1%