What is Lung Cancer?

Lung cancer affects the lungs but can originate in any part of respiratory system or also known as the breathing system. The respiratory system includes the nose and mouth, windpipe (trachea), airways to each lung (left and right bronchus) and lungs.

Lung cancer is widely associated with tobacco and smoking, and this is the main cause of lung cancer. Given this, nearly all lung cancers can be prevented.

Types of lung cancer

Non-Small Cell Lung Cancer

Adenocarcinoma is the most prevailing type of lung cancer and makes up about 80% of all such cases. It mainly happens in people who smoke (or who used to). And it’s also the No. 1 type of lung cancer among non-smokers.

Statistically affects more women than men, and patients tend to be younger as compared with other kinds of lung cancer.

Adenocarcinoma can spread to the lymph nodes, bones, or other organs such as the liver.

Squamous cell carcinoma predominantly originates in the lung’s largest branches, which doctors call the “central bronchi.”    

This type accounts for 30% of lung cancers, and it’s more common in men and people who smoke. It may form a cavity within the tumor and usually affects the larger airways. It may make you cough up some blood.

Squamous cell carcinoma can also spread to the lymph nodes, bones, and other organs such as the liver. 

Large-cell carcinomas are a group of cancers with large cells that tend to start along the lungs’ outer edges. They're less common than adenocarcinoma or squamous cell carcinoma, making up 10%-15% of lung cancers. This type of tumor can grow faster and often spreads to nearby lymph nodes and distant parts of the body.

Small Cell Lung Cancer

This is the most aggressive form of the disease. It commonly begins in the lungs’ large, central bronchi. Almost all those diagnosed are smokers and it spreads quickly, often before any symptoms appear. Often, the cancer can spread to the liver, bone and brain.

Most lung cancers can be prevented as they are related to smoking (or second-hand smoke) or exposure to radon or other environmental factors.


At Sunway Medical Centre, we work with a multidisciplinary team to create a treatment plan that is best suited for the patient. The treatment of colorectal cancer depends on several factors including the patients’ health history, the stage of the cancer etc. The three most common treatment options are:


Surgery is the removal of the tumor and some surrounding healthy tissue during an operation. This is the most common treatment for colorectal cancer and is often called surgical resection. Surgical options for colorectal cancer include the Laparoscopic surgery or the traditional open surgery.

With Laparoscopic surgery, three or four tiny cuts are made which allows for a quicker recovery time with minimal blood loss. However, with an Open surgery, the surgeon makes a large cut into your abdomen to remove the tumor and this leads to a longer hospital stay with slower recovery time.


Chemotherapy refers to treatment using medicines to kill cancer cells. Chemotherapy is usually given in cycles, administering a treatment for a period of time followed by a rest to allow your body time to recover . Chemotherapy may be given after a surgery to eliminate any remaining cancer cells. For patients with rectal cancer, chemotherapy and radiation therapy are given before a surgery to reduce the size of the tumor and reduce the chances of the cancer returning.

Radiation Therapy

Radiation therapy is the use of high-energy x-rays to destroy cancer cells. It is commonly used for treating rectal cancer because colorectal tumor tends to recur near where it originally started. Doctors use different types of radiation therapy to treat cancer. Sometimes people receive a combination of external or internal radiation as well as the Intraoperative radiation therapy.

Side effects depend mainly on the amount of radiation given and the part of your body that is treated. They can include nausea, vomiting, diarrhoea, bloody stools or urgent bowel movements, urinary and skin sensitivity problems.