lung cancer

Facts about lung cancer

Q 1 what is lung cancer?

Lung cancer begins in the lungs. The lungs are a pair of spongy, air-filled organs located on either side of the chest (thorax). The trachea (windpipe) conducts inhaled air into the lungs through bronchi.

The lungs absorb oxygen from the air you breathe in and transfer it into your bloodstream so that it can get to every part of your body.

Q 2 what are causes of lung cancer?

  • Smoking:Majority of cases are due to smoking and in people exposed to secondhand smoke. Your risk of lung cancer increases with the number of cigarettes you smoke each day and the number of years you have smoked. Quitting at any age can significantly lower your risk of developing lung cancer.
  • Previous radiation therapy to chest
  • Exposure to radon gas
  • Exposure to asbestos, arsenic, chromium and nickel
  • Family history of lung cancer

Q 3 what are the types of lung cancer?

  • Non-small cell lung cancer
  • Squamous cell carcinoma
  • Adenocarcinoma and
  • Large cell carcinoma
  • Small cell lung cancer

Small cell lung cancer occurs almost exclusively in heavy smokers and is less common than non-small cell lung cancer.

  • Lung carcinoid tumors
  • Adenoid cystic carcinomas
  • Lymphomas
  • Sarcomas

Q 4 what are the symptoms of lung cancer?

There are usually no signs or symptoms in the early stages. Symptoms of lung cancer develop as the condition progresses.

  • Cough that doesn’t go away after 2 or 3 weeks
  • Chest infections that keep coming back
  • Coughing up blood
  • Pain when breathing or coughing
  • Persistent breathlessness
  • Loss of appetite or unexplained weight loss
  • Difficulty swallowing (dysphagia)or pain when swallowing
  • A hoarse voice
  • Swelling on face or neck
  • Persistent chest or shoulder pain

Q 5 what is lung cancer screening?

Screening is done in normal person and is used to look for cancer before you have any symptoms or signs

The American Cancer Society (ACS) recommends yearly lung cancer screening with Low dose CT scan for people who are:

  • 55 to 74 years old and
  • Are in fairly good health and
  • Are current smokers or smokers who have quit in the past 15 years and
  • Have at least a 30 pack-year smoking history

Q 6 How is lung cancer diagnosed?

  • A chest X-ray is usually the 1st test done for any lung problem
  • A CT scan chest is usually the next test

If CT scan shows lung mass then biopsy is done.

  • Biopsy is done for confirmation and to know type of cancer. Biopsy can be done either by CT scan guided or by bronchoscopy

A bronchoscopy is a procedure that allows a doctor to see the inside of your airways and remove a small biopsy.

During a bronchoscopy, a thin tube with a camera at the end, called a bronchoscope, is passed through your mouth or nose, down your throat and into your airways.

A word of caution

There is common myth that taking biopsy leads to spread of cancer cells in body. This is not true. Taking biopsy does not lead to spread of cancer cells in body.

Biopsy confirms that it is a cancer and not infection and also helps in knowing the type of cancer so that further treatment can be planned accordingly. 

  • Once a diagnosis of cancer is made further imaging studies are done for spread of disease in body
  • PET-CT scan to know distant spread of disease
  • MRI brain to know spread of disease in brain

Q 7 What is lung cancer staging?

Staging is a measurement of how far the cancer has spread.

After all the tests have been completed and the results are known, it should be possible to predict what stage the cancer is. The higher the stage, the further the cancer has spread.

  • Non-small cell lung cancer has four main stages:

Stage 1: Cancer is found in the lung, but it has not spread outside the lung.

Stage 2: Cancer is found in the lung and nearby lymph nodes.

Stage 3: Cancer is in the lung and lymph nodes in the middle of the chest.

Stage 4: Cancer has spread to both lungs, into the area around the lungs, or to distant organs.

  • Small-cell lung cancer (SCLC) has two main stages.
  • In the limited stage, cancer is found in only one lung or nearby lymph nodes on the same side of the chest
  • The extensive stage means cancer has spread
  1. to the opposite lung
  2. to lymph nodes on the opposite side
  3. to fluid around the lung
  4. to bone marrow
  5. to distant organs

A word of caution,

Above staging is simplified version for your basic understanding. Reader is advised to follow TNM staging system developed by American Joint Committee on Cancer (AJCC) in which

  • T stands for the size and location of primary tumor
  • N stands for nodes. It tells whether the cancer has spread to the nearby lymph nodes
  • M stands for metastasis. It tells whether the cancer has spread to distant parts of the body

Q 8 How is lung cancer treated?

Lung cancer is curable if diagnosed at an early stage. Surgery is the only curative options.

When deciding treatment options for a particular patient, doctor will consider following factors and will decide individual treatment plan:

  • The size of the cancer
  • The stage of the cancer
  • The location of the cancer
  • Your overall health and ability to recover from surgery, radiation therapy or chemotherapy
  • Your personal preferences

Following are the general guidelines but treatment may vary from patient to patient: 

Non-Small Cell Lung Cancer

  • Localized lung cancer (stage 1 &2)

Surgery followed by chemotherapy +/- radiation therapy

  • Locally advanced lung cancer (stage 3)

Combination of radiation therapy, chemotherapy and/or surgery.

  • Advanced lung cancer (stage4)

Chemotherapy

Targeted therapy

Immunotherapy

Small cell lung cancer (SCLC)

  • Limited stage SCLC

Chemo therapy plus radiation therapy to the chest given at the same time

If cancer respond well to initial treatment, then radiation therapy is given to the head (prophylactic cranial irradiation, or PCI)

  • Extensive stage SCLC

Chemotherapy, possibly along with an immunotherapy drug, is typically the first treatment.

If the cancer responds well to the initial treatment, then radiation to the chest and brain may be given.

Surgery

Types of surgery

  • Wedge or segmental resection
  • Lobectomy removes a lobe of the lung
  • Pneumonectomy removes the whole lung.
  • Extended pulmonary resection removes the muscles, nerves, blood vessels and other tissues near the lung to take out as much of the cancer as possible.
  • Chest wall resection removes the muscles, bones and other tissues of the chest wall.

Treatment of pleural effusion (fluid buildup in the area around the lung)

  • Thoracentesis

Thoracentesis is a procedure done to drain the fluid. With the help of ultrasound, a hollow needle is inserted into the space between the ribs to drain the fluid around the lung.

  • Pleurodesis

Pleurodesis is a procedure done to remove the fluid and keep it from coming back. The 2 main types are:

  • Chemical pleurodesis: A small cut is made in the skin of the chest wall and a hollow tube (called a chest tube) is placed into the chest to remove the fluid. Then a substance is put into the chest through the tube that causes the linings of the lung (visceral pleura) and chest wall (parietal pleura) to stick together, sealing the space and limiting further fluid buildup. Most commonly used chemical is talc or bleomycin.
  • Surgical pleurodesis: Talc is blown into the space around the lungs during an operation. This is done using thoracoscopy through a small incision.