LUNG CANCER FACTS


Lung cancer is the most common type of cancer in both men and women in this country. Most cases are linked to tobacco smoking.

The lungs, which help you breathe, are two sponge-like, cone-shaped organs in the chest. When you breathe in, oxygen comes through your mouth and nose. It then travels through the windpipe (trachea), which divides into two tubes called bronchi. These take the oxygen to the left and right lungs. The inside of the lungs includes smaller branches called bronchioles and alveoli, which are tiny air sacs.

Each lung is divided into sections called lobes. The right lung has three lobes. The left lung, which has two lobes, is smaller than the right lung because the heart is also on the left side of the body.

The pleura is a thin membrane that covers the outside of each lung and lines the inside wall of the chest. It usually contains a small amount of fluid and forms a protective lining around the lungs that allows them to move smoothly during breathing.

Cancer Grows in Lungs, May Spread

Lung cancer forms in the tissues of the lungs, most often in the cells that line air passages. It occurs when cells in your lungs grow and multiply uncontrollably, damaging surrounding tissue and interfering with the lungs’ normal function.

Lung cancer may spread through your lymph system. Lymph is a clear fluid that contains tissue waste and cells that help fight infection. It travels through your body in vessels that are similar to veins. Lymph nodes are small, bean-shaped organs that link lymph vessels.

Cancer cells can spread, or metastasize, to other parts of your body through the bloodstream as well. When lung cancer spreads to other organs, it still is called lung cancer.

Lung Cancer Types

Lung cancer is classified by the type of cells within the tumor. Each type of lung cancer grows and is treated in a different way. Lung cancers are divided into two main groups.

Non-small cell lung cancer (NSCLC): This is the most common type of lung cancer. The categories of non-small cell lung cancer are named for the type of cells in the cancer:

  • Adenocarcinoma begins in cells that line the alveoli and make mucus. It is found more often in nonsmokers, women          and younger people.
  • Squamous cell carcinoma (cancer) begins in thin, flat cells in the lungs, and tobacco smoking most often causes it. It        also is called epidermoid carcinoma.
  • Large cell carcinoma (cancer) begins in certain types of large cells in the lungs.



Small cell lung cancer: Also known as oat-cell cancer, this type of lung cancer makes up less than 20% of lung cancers and almost always is caused by tobacco smoking. It often starts in the bronchi, then quickly grows and spreads to other parts of the body, including the lymph nodes.

Other types of lung cancer

Less common types of lung cancer include:

  • Carcinoid tumors
  • Salivary gland carcinoma
  • Some sarcomas
  • Cancer of unknown primary



Lung metastases

Cancer found in the lungs is sometimes another type of cancer that started somewhere else in the body and spread, or metastasized, to the lungs. These tumors are called lung metastases, and they are not the same as lung cancer. They usually are the primary, or original, type of cancer.

In rare cases, lung cancer can be passed down from one generation to the next. Genetic counseling may be right for you. 

Some people have an elevated risk of developing lung cancer. 

Behavioral and lifestyle changes can help prevent lung cancer. 

 
Risk Factors

Anything that increases your chance of getting lung cancer is a risk factor. Smoking is the main risk factor for lung cancer.

  • Smoking tobacco in cigarettes, cigars or pipes is responsible for 87% of lung cancer cases.
  • The more years you smoke and the greater amount you smoke, the higher your risk of lung cancer.
  • If you stop smoking, your risk of lung cancer becomes lower as time goes by.
  • If you smoke and have other risk factors, your chance of getting lung cancer is higher. ​



Other risk factors for lung cancer include:

  • Family history of lung cancer
  • Previous lung cancer
  • Exposure to certain materials including radiation, arsenic, radon, chromium, nickel, soot, tar or asbestos
  • Radiation therapy to the breast or chest
  • Air pollution
  • Secondhand smoke
  • Lung diseases such as tuberculosis (TB)


Not everyone with risk factors develops lung cancer. However, if you have risk factors, it’s a good idea to discuss them with your doctor.



LUNG CANCER SYMPTOMS


​Lung cancer symptoms vary from person to person, and sometimes people with lung cancer don’t have symptoms. If you have symptoms, they may include:

  • A cough that does not go away and gets worse over time
  • Constant chest pain, often made worse by deep breathing, coughing or laughing
  • Arm or shoulder pain
  • Coughing up blood or rust-colored spit
  • Shortness of breath, wheezing or hoarseness
  • Repeated episodes of pneumonia or bronchitis
  • Swelling of the neck and face
  • Loss of appetite and/or weight loss
  • Feeling weak or tired
  • Clubbing of fingers


If lung cancer spreads to other parts of the body, it may cause:

  • Bone pain
  • Arm or leg weakness or numbness
  • Headache, dizziness or seizure
  • Jaundice (yellow coloring) of skin and eyes
  • Swollen lymph nodes in the neck or shoulder


These symptoms do not always mean you have lung cancer. However, it is important to discuss any symptoms with your doctor, since they may also signal other health problems.


LUNG CANCER DIAGNOSIS


​If you have lung cancer, it is important to get an accurate diagnosis as early as possible and find out if the cancer has spread. This will help your doctors choose the best type of treatment.

If you have symptoms that may signal lung cancer, your doctor will ask you questions about your medical, smoking and family history and whether you have been around certain chemicals or substances.

Lung Cancer Diagnosis

If you have symptoms that may signal lung cancer, your doctor will examine you and ask you questions about your health; your lifestyle, including smoking habits; your family history; and whether you have been around certain chemicals or substances.

One or more of the following tests may be used to find out if you have lung cancer and if it has spread. These tests also may be used to find out if treatment is working.

The two main tests to find out if you have lung cancer are:

  • Chest X-rays: Photographs of the lungs to look for abnormal areas.
  • Sputum cytology: A sample of mucus or phlegm brought up by coughing is looked at under a microscope.


If chest X-rays show an abnormal area, one or more of these tests may be used to find out if you have lung cancer:

Bronchoscopy: A thin flexible tube with a tiny camera is inserted through the nose or mouth and down into the lungs. A bronchoscope also can be used to take a small tissue sample for biopsy.

Fine needle aspiration (FNA): A very small needle is placed into the tumor. Suction is used to remove a small amount of tissue, which is then looked at under a microscope.

Thoracentesis: Fluid from around the lungs is drawn out with a needle and looked at under a microscope.

Endobronchial Ultrasound (EBUS): Guided biopsy to check for lung cancer and find out if cancer has spread to nearby lymph nodes.

Video-Assisted thoracoscopic surgery (VATS) 

Imaging tests, which may include:

  • CT or CAT (computed axial tomography)
  • MRI (magnetic resonance imaging) scans
  • PET (positron emission tomography) scans



STAGE I

If you are diagnosed with lung cancer, your doctor will determine the stage (or extent) of the disease. This is a way to classify the cancer by how far and to which parts of the body it has spread. Staging helps the doctor plan the best treatment for you. Once the staging classification is determined, it stays the same even if treatment works or the cancer spreads.

Staging is often the most important part of your treatment. If the cancer is staged improperly, you may not receive the right treatment.



STAGE II



​Small-cell lung cancer stages

Limited stage: Cancer is in one lung and possibly in lymph nodes on the same side of the chest.

Extensive stage: Cancer has spread to the other lung, to lymph nodes on the other side of the chest, to the fluid around the lung or to other parts of the body.

Non-small cell lung cancer stages

Stage 0 through stage IB tumors in which cancer has not spread to the lymph nodes are considered early stage lung cancer.

Occult stage: Lung cancer cells are found in spit or in a sample of mucus (phlegm) taken during bronchoscopy, but a tumor cannot be seen in the lung by imaging or bronchoscopy, or a tumor is present but is too small to be biopsied.

Stage 0: Abnormal cells are found only in the innermost lining of the lung. The tumor has not grown through this lining. A stage 0 tumor is also called carcinoma in situ. The tumor is not an invasive cancer.

Stage IA: The lung tumor is an invasive cancer. It has grown through the innermost lining of the lung into deeper lung tissue. The tumor is no more than 3 centimeters across. It is surrounded by normal tissue and does not invade the bronchus. Lung cancer cells are not found in nearby lymph nodes.

Stage IB: The tumor is larger or has grown deeper, but lung cancer cells are not found in nearby lymph nodes. The lung tumor is one of the following:

  • More than 3 centimeters across
  • Grown into the main bronchus
  • Grown through the lung into the pleura


Stage IIA: The lung tumor is no more than 3 centimeters across. Lung cancer cells are found in nearby lymph nodes.

Stage IIB: The lung cancer is one of the following:

  • Not found in nearby lymph nodes but has invaded the chest wall, diaphragm, pleura, main bronchus or tissue that            surrounds the heart
  • Cancer cells are found in nearby lymph nodes and the tumor in the lung is one of the following:
  • More than 3 centimeters across
  • Grown into the main bronchus
  • Grown through the lung into the pleura


Stage IIIA: The tumor may be any size. Lung cancer cells are found in the lymph nodes near the lungs and bronchi and in the lymph nodes between the lungs on the same side of the chest as the lung tumor.

Stage IIIB: The tumor may be any size. Lung cancer cells are found on the opposite side of the chest from the lung tumor or in the neck. The tumor may have invaded nearby organs, such as the heart, esophagus or trachea. More than one malignant growth may be found within the same lobe of the lung. Cancer cells may be found in the pleural fluid.

Stage IV: Tumors may be found in more than one lobe of the same lung or in the other lung. Lung cancer cells may be found in other parts of the body, such as the brain, adrenal gland, liver or bone.


TREATMENT

Treatment for lung cancer depends on the type of cancer, its spread, and the patient's performance status. Common treatment options are surgery, chemotherapy, and radiation therapy.

  • Surgery – Diagnostic surgery is done to obtain tissue for pathologic diagnosis of cancer. It includes Trucut Biopsy and      incisional or excisional biopsy. In most cases of initial-stage non-small cell lung cancer, lobectomy (removal of a lobe of    lung) is the most preferred surgical option. In rare cases, pneunmonectomy (removal of the entire lung) is done.
  • Chemotherapy – This option is often used when the cancer has spread outside the lungs.
  • Radiation Therapy – Radiotherapy is often done along with chemotherapy. Radiation therapy involves the use of high      energy X Rays that destroy cancer cells and shrink tumors. About half of all people with cancer are treated with                radiation therapy, either alone or in combination with other types of cancer treatment. There are mainly three types of        radiation therapy done to treat cancer – 3DCRT (three-dimensional conformal radiation therapy),IMRT, and IGRT             (image-guided radiation therapy). 

LUNG CANCER