Lung cancer is a type of cancer that starts in the lungs. Cancer starts when cells in the body begin to grow out of control. lungs are 2 sponge-like organs in your chest. Right lung has 3 sections, called lobes. Left lung has 2 lobes. The left lung is smaller because the heart takes up more room on that side of the body.

When breathe in, air enters through your mouth or nose and goes into your lungs through the trachea (windpipe). The trachea divides into tubes called bronchi, which enter the lungs and divide into smaller bronchi. These divide to form smaller branches called bronchioles. At the end of the bronchioles are tiny air sacs known as alveoli. The alveoli absorb oxygen into your blood from the inhaled air and remove carbon dioxide from the blood when you exhale. Taking in oxygen and getting rid of carbon dioxide are your lungs’ main functions.

Lung cancers typically start in the cells lining the bronchi and parts of the lung such as the bronchioles or alveoli. Lung cancer begins in the lungs and may spread to lymph nodes or other organs in the body, such as the brain. Cancer from other organs also may spread to the lungs. When cancer cells spread from one organ to another, they are called metastases.

Lung cancers usually are grouped into two main types called small cell and non-small cell (including adenocarcinoma and squamous cell carcinoma). These types of lung cancer grow differently and are treated differently. Non-small cell lung cancer is more common than small cell lung cancer

Almost lung cancers do not cause any symptoms until they have spread, but some people with early lung cancer do have symptoms. If you have symptoms, you might be diagnosed at an earlier stage, when treatment is more likely to be effective. Most of these symptoms are more likely to be caused by something other than lung cancer.
The most common symptoms of lung cancer are:
• Coughing up blood or rust-colored sputum (spit or phlegm)
• Chest pain that is often worse with deep breathing, coughing, or laughing
• A cough that does not go away or gets worse
• Hoarseness
• Loss of appetite
• Unexplained weight loss
• Shortness of breath
• Feeling tired or weak
• Infections such as bronchitis and pneumonia that don’t go away or keep coming back
• New onset of wheezing

If lung cancer spreads to other parts of the body, it may cause:
• Bone pain
• Nervous system changes from cancer spread to the brain
• Yellowing of the skin and eyes from cancer spread to the liver
• Swelling of lymph nodes (collection of immune system cells) such as those in the neck or above the collarbone

Some lung cancers can cause syndromes, which are groups of specific symptoms:
1) Superior vena cava syndrome
The superior vena cava (SVC) is a large vein that carries blood from the head and arms down to the heart. It passes next to the upper part of the right lung and the lymph nodes inside the chest. Tumors in this area can press on the SVC, which can cause the blood to back up in the veins. This can lead to swelling in the face, neck, arms, and upper chest (sometimes with a bluish-red skin color). It can also cause headaches, dizziness, and a change in consciousness if it affects the brain. While SVC syndrome can develop gradually over time, in some cases it can become life-threatening, and needs to be treated right away.

2) Horner syndrome
Cancers of the upper part of the lungs are sometimes called Pancoast tumors. These tumors are more likely to be non-small cell lung cancer (NSCLC) than small cell lung cancer (SCLC).
Pancoast tumors can affect certain nerves to the eye and part of the face, causing a group of symptoms called Horner syndrome:
• Drooping or weakness of one upper eyelid
• A smaller pupil (dark part in the center of the eye) in the same eye
• Little or no sweating on the same side of the face
Pancoast tumors can also sometimes cause severe shoulder pain.

3) Paraneoplastic syndromes
Some lung cancers make hormone-like substances that enter the bloodstream and cause problems with distant tissues and organs, even though the cancer has not spread to those places. These problems are called paraneoplastic syndromes. Sometimes these syndromes may be the first symptoms of lung cancer. Because the symptoms affect other organs, a disease other than lung cancer may first be suspected as causing them.

4) Paraneoplastic syndromes
Paraneoplastic syndromes can happen with any lung cancer but are more often associated with SCLC. Some common syndromes include:
• SIADH (syndrome of inappropriate anti-diuretic hormone): In this condition, the cancer cells make ADH, a hormone that causes the kidneys to hold water. This lowers salt levels in the blood. Symptoms of SIADH can include fatigue, loss of appetite, muscle weakness or cramps, nausea, vomiting, restlessness, and confusion. Without treatment, severe cases may lead to seizures and coma.
• Cushing syndrome: In this condition, the cancer cells make ACTH, a hormone that causes the adrenal glands to make cortisol. This can lead to symptoms such as weight gain, easy bruising, weakness, drowsiness, and fluid retention. Cushing syndrome can also cause high blood pressure, high blood sugar levels, or even diabetes.
• Nervous system problems: SCLC can sometimes cause the body’s immune system to attack parts of the nervous system, which can lead to problems. One example is a muscle disorder called Lambert-Eaton syndrome. In this syndrome, muscles around the hips become weak. One of the first signs may be trouble getting up from a sitting position. Later, muscles around the shoulder may become weak. A less common problem is paraneoplastic cerebellar degeneration, which can cause loss of balance and unsteadiness in arm and leg movement, as well as trouble speaking or swallowing. SCLC can also cause other nervous system problems, such as muscle weakness, sensation changes, vision problems, or even changes in behavior.
• High levels of calcium in the blood (hypercalcemia), which can cause frequent urination, thirst, constipation, nausea, vomiting, belly pain, weakness, fatigue, dizziness, and confusion
• Blood clots

Smoking
Smoking tobacco is the number one risk factor for lung cancer. Tobacco smoke contain more than 7,000 chemicals, many of which are carcinogenic. Examples of carcinogenic chemicals contained in tobacco smoke are nitrogen oxide and carbon monoxide.
Inhaling the chemicals in a cigarette immediately triggers a change in lung tissue. Initially, body may be able to repair the damage, but its ability to repair decreases as exposure continues. The more frequent and the longer you smoke, the greater your chance for lung cancer.
Radiation therapy to the chest
Radiation therapy used to treat other cancers like non-Hodgkin’s lymphoma and breast cancer may increase your risk for lung cancer. This risk is higher if you smoke.
Secondhand smoke
Even if you don’t smoke, being exposed to secondhand smoke can increase your risk for lung cancer. This exposure can occur at any place you spend time, such as:
• home
• work
• restaurants
• bars
Radon
Radon is a gas that occurs naturally with the breakdown of uranium in rocks and soil. It’s odorless, colorless, and tasteless. This gas can seep into building foundations and into living and working spaces. Radon is difficult to detect and you could be exposed without knowing it.
The effects of radon present an increased risk to people who smoke as opposed to those who don’t smoke. Radon is the second leading cause of lung cancer in the world.
Asbestos
Asbestos is an industrial material used in construction for insulation and as a fire retardant. When the material is disturbed, small fibers become airborne and can be inhaled. You’re at a greater risk for developing lung cancer if you’re exposed to asbestos on a regular basis.
Other chemicals
Other chemical exposures can raise your risk for lung cancer. Some examples are:
• arsenic
• beryllium
• cadmium
• vinyl chloride
• nickel compounds
• chromium compounds
• coal products
• mustard gas
• chloromethyl ethers
• diesel exhaust
Genetics
Research suggests that if a member of your immediate family has had lung cancer, you may have a slightly higher risk for developing the disease. Immediate family includes the following relations:
• mother
• father
• sibling
• aunt
• uncle
• grandparent
This elevated risk is true even if you don’t smoke. It’s unclear whether genetics causes lung cancer or merely increases your susceptibility to it.
Age
Lung cancer mostly occurs in older adults. The average age at the time of diagnosis is about 70. The older you are, the longer you have been exposed to harmful chemicals. This longer exposure increases your risk for cancer.
Diet
A balanced diet provides your body with the vitamins and minerals it needs to maintain good health. If you don’t eat a diverse mix of healthy foods, including fruits and vegetables, you may have an increased risk for lung cancer. This is especially true if you smoke tobacco.

The stage of lung cancer describes the progression or extent of the cancer. If you receive a lung cancer diagnosis, the stage will help doctor create a treatment plan for you. Lung cancer is mainly classified as either small-cell or non-small cell lung cancer. Non-small cell lung cancer is more common.

1) Stages of non-small cell lung cancer
Non-small cell lung cancer may be anywhere from stage 0 to 4, with letters showing additional levels of progression. Many of the stages have different combinations of factors that may still be labeled as the same stage. For example, lung cancer with a smaller tumor that has spread to the lymph nodes and cancer with a larger tumor that has not spread to the lymph nodes may both be stage 2B

2) Stages of small-cell lung cancer
The same numbering system may be used for both types of lung cancer, but it mostly applies to non-small cell lung cancer. Small-cell lung cancer is usually identified by two stages, called “limited” and “extensive.”
The limited stage is confined to the chest and is usually in one lung and neighboring lymph nodes. Standard treatments include chemotherapy and radiation therapy.
Small-cell lung cancer is more likely to be diagnosed in the extensive stage. This stage involves both lungs and other parts of the body. Doctors usually treat this stage with chemotherapy and supportive care, and may also use immunotherapy and radiation.

Doctor may use a variety of tests and scans to look for the presence of lung cancer. Next, other tests like a sputum cytology or biopsy will examine your lung cells for cancer to confirm the diagnosis.
1) Physical exam
Doctor will ask about your symptoms and medical history. They will check your vital signs like heart rate and blood pressure, listen to your breathing, and check for swollen lymph nodes. They may order additional testing if they notice anything abnormal
2) Bronchoscopy
Doctor will insert a thin, lighted tube called a bronchoscope through your mouth or nose and down into your lungs to examine the bronchi and lungs. They may take a cell sample for examination
3) CT scan
A CT scan is an X-ray that takes internal pictures as it rotates around your body, providing a more detailed image of your internal organs. It may involve swallowing contrast dye or having it injected into your vein.
4) Sputum cytology
Sputum, or phlegm, is a thick fluid you cough up from your lungs. Your doctor will send a sputum sample to a lab for microscopic examination for any cancer cells or other abnormal cells.
5) Lung biopsy
Imaging tests can help your doctor detect masses and tumors. Some tumors can have characteristics that are suspicious, but radiologists can’t be certain if they’re benign or malignant.
Only examining lung cells through biopsies or other tests can help doctor verify whether suspicious lung lesions are cancerous. A biopsy will also help them determine the type of cancer and help guide treatment. Several methods of lung biopsy include the following:
•Fine needle aspiration. :
Doctor will use a thin needle to take cells from your lungs or lymph nodes.
•Core biopsy. :
A core biopsy is similar to a fine needle aspiration. Your doctor will use a needle to take a larger sample called a “core.”
•Thoracentesis. :
Doctor will insert a long needle between your ribs to take a sample of fluid, called pleural effusion, between the layers of tissue lining your lung. They may also perform a pleural biopsy to take a sample of the tissue itself.
•Mediastinoscopy.:
Doctor will insert a thin, lighted tube through a small incision at the top of your breastbone to visualize and take tissue and lymph node samples.
•Endobronchial ultrasound. :
Your doctor will use sound waves to guide a bronchoscope down your trachea, or “windpipe,” to look for tumors and create images of them if they’re present. They may take samples from the areas in question.
•Thoracoscopy. :
Your doctor will make small incisions in your chest and back to examine lung tissue with a thin tube. This procedure can check if the cancer has spread and can also take tissue samples.
•Thoracotomy.:
Surgeon will make a long incision in your chest to remove lymph node tissue and other tissue for examination. This major procedure is often used to treat lung cancer rather than to diagnose it.
•MRI. :
Doctor may order an MRI when they suspect lung cancer may have spread to the brain or spine.
•PET scan. :
This scan involves the injection of a radioactive drug, or tracer, which will collect in cancer cells and allow doctor to see the areas with cancer. It may be combined with a CT scan for a more detailed image.
•Bone scans. :
Doctors may order bone scans if they suspect cancer has spread to the bones. These involve injecting radioactive material into your vein, which builds up in abnormal or cancerous areas of the bone. They can then see the abnormal areas through imaging.

Doctor choose a cancer treatment plan based on a number of factors, such as your overall health, the type and stage of your cancer, and your preferences.
Surgery
During surgery, your surgeon works to remove the lung cancer and a margin of healthy tissue. Procedures to remove lung cancer include:
•Wedge resection to remove a small section of lung that contains the tumor along with a margin of healthy tissue
•Segmental resection to remove a larger portion of lung, but not an entire lobe
•Lobectomy to remove the entire lobe of one lung
•Pneumonectomy to remove an entire lung
If you undergo surgery, your surgeon may also remove lymph nodes from your chest in order to check them for signs of cancer. Surgery may be an option if your cancer is confined to the lungs. If you have a larger lung cancer, your doctor may recommend chemotherapy or radiation therapy before surgery in order to shrink the cancer.
Radiation therapy
Radiation therapy uses high-powered energy beams from sources such as X-rays and protons to kill cancer cells. During radiation therapy, you lie on a table while a machine moves around you, directing radiation to precise points on your body. For people with locally advanced lung cancer, radiation may be used before surgery or after surgery. It's often combined with chemotherapy treatments. For advanced lung cancers and those that have spread to other areas of the body, radiation therapy may help relieve symptoms, such as pain.
Chemotherapy
Chemotherapy uses drugs to kill cancer cells. One or more chemotherapy drugs may be given through a vein in your arm (intravenously) or taken orally. A combination of drugs usually is given in a series of treatments over a period of weeks or months, with breaks in between so that you can recover. Chemotherapy is often used after surgery to kill any cancer cells that may remain. It can be used alone or combined with radiation therapy. Chemotherapy may also be used before surgery to shrink cancers and make them easier to remove.
Stereotactic body radiotherapy
Stereotactic body radiotherapy, also known as radiosurgery, is an intense radiation treatment that aims many beams of radiation from many angles at the cancer. Stereotactic body radiotherapy treatment is typically completed in one or a few treatments.
Targeted drug therapy
Targeted drug treatments focus on specific abnormalities present within cancer cells. By blocking these abnormalities, targeted drug treatments can cause cancer cells to die. Many targeted therapy drugs are used to treat lung cancer, though most are reserved for people with advanced or recurrent cancer. Some targeted therapies only work in people whose cancer cells have certain genetic mutations. Your cancer cells may be tested in a laboratory to see if these drugs might help you.
Immunotherapy
Immunotherapy uses your immune system to fight cancer. Your body's disease fighting immune system may not attack your cancer because the cancer cells produce proteins that help them hide from the immune system cells. Immunotherapy works by interfering with that process. Immunotherapy treatments are generally reserved for people with locally advanced lung cancers and cancers that have spread to other parts of the body.
Palliative care
People with lung cancer often experience signs and symptoms of the cancer, as well as side effects of treatment. Supportive care, also known as palliative care, is a specialty area of medicine that involves working with a doctor to minimize your signs and symptoms.

5-year relative survival rates for lung cancer:
•Localized: 63% There is no sign that the cancer has spread outside of the lung.
•Regional: 35% The cancer has spread outside the lung to nearby structures or lymph nodes.
•Distant: 7% The cancer has spread to distant parts of the body, such as the brain, bones, liver, or the other lung.

Cancer is a life threatening disease that can affect anyone regardless of race, age, and gender. Traditional cancer treatments like radiotherapy and chemotherapy often result in undesirable and uncomfortable side effects such as vomiting, numbness, nausea, and diarrhea to name a few. Herbal medicine is a complementary therapy that some people with cancer use to ease cancer symptoms. Herbal remedies for cancer such as those commonly found in traditional medicine contains antimutagenic, anti-inflammatory, and apoptosis inducing compounds that help in slowing the development of cancer and relieve treatment side effects for patients.

Herbal medicine has a wide variety of applications but all of them rely on the sustainable use of various plant parts such as flowers, leaves, bark, and roots. Each part of a plant features different medicinal properties and uses. Although herbal medicine has countless use cases, cancer care is one of the most practical applications because of how harsh traditional oncology treatments can be on patients.

Herbal remedies are a part of a growing field of medicine called integrative oncology. Research conducted on the use of herbal medicine for cancer complementary therapy has proven herbs can:
• Slows the spread of cancer
• Reduces the side effects of cancer treatment
• Boosts immune system strength and functionality
• Minimizes the symptoms of cancer
• Attacks cancer cells

Several herbs may help control the side effects of conventional cancer treatment. However, doctors do not recommend that cancer patients take herbal medicine while undergoing normal traditional cancer treatment. Herbal medicines may be likely less to cause side effects than traditional drugs. But patients may can still experience complications. Some herbs may can cause negative interactions with chemotherapy drugs. Closely monitor how you feel before and after taking herbal remedies. Patients should always consult with their doctor before trying herbs as a complementary therapy or the supplements to avoid complications.