Cancer is a major health problem all over the world. In Malaysia, it ranks second in the list as a principal cause of death, resulting in 4,701 cases or 10.8% of the 43,514 medically certified death in 1998. In 2000, there were 40,244 admissions of cancer patients into government hospitals, an increase of 54% as compared to 26,142 admissions in 1991. The number of deaths from cancer in government hospitals had also gone up by 29% from 2,196 deaths in 1991 to 2,832 deaths in 2000. Every hour, four persons discover that they suffer from cancer. With the number of senior citizens above 60 increasing to about 11% by 2020 and the surging prevalence of unhealthy lifestyle associated with affluence, such as smoking, inappropriate diet, excessive weight gain and lack of exercise, the incidence of cancer is expected to rise.

Chest X-ray confirming multiple pulmonary metastases

What is Cancer?
The term cancer refers to a group of more than 100 different diseases. Cancer develops when cells become abnormal and keep dividing and forming more cells without control or order.

All organs of the body are made up of cells. Normally, cells divide to produce more cells only when the body needs them. If cells divide when new ones are not needed, they form a mass of excess tissue, a lump. This is called a tumor. Tumors can be benign (not cancer) or malignant (cancer).

The differences between a benign (non cancerous) lump and malignant (cancerous) lump are two:-

1. Cells in malignant tumors can invade and damage nearby tissues and organs.
2. Cells in malignant tumors can break away from the parent tumor and travel through the bloodstream and lymphatic system to form new tumors in other parts of the body. The spread of cancer is called metastasis.

Different types of cancer can behave very differently. For example, lung cancer and breast cancer are very different diseases. They grow at different rates and respond to different treatments. That is why people with cancer need treatment that is aimed at their particular kind of cancer.

Cancer can take years to develop. By the time a cancerous mass can be detected on a routine chest x-ray, about 1 billion cancer cells are present and that original cancer cell has been dividing for 6 to 8 years. Likewise, once a lump can be felt in the breast, it may have been present for 3 to 5 years.

Cancers have no nerves so they do not hurt, but they can cause other structures to hurt because of the destruction or pressure on the normal structures. Therein lies a major problem. Many patients note a lump on their body but because it is not painful, they ignore it. By the time pain develops, the cancer is often advanced as nearby structures will have been invaded.

CT image showing enhancement of multiple gliomas

CT image showing liver metastases

A) Low-grade squamous intraepithelial lesion
B) High-grade squamous intraepithelial lesion
C) Squamous cell carcinoma
D) Adenocarcinoma

What causes Cancer?
In many cases, the exact nature of cancer remains a mystery. We know that certain changes in our cells cause cancer to start, but we do not yet know exactly how this happens. There are several risk factors that increase a person's chance of developing cancer. Different cancers have different risk factors. For example, smoking is a risk factor for cancers of the lungs, mouth, throat, larynx, bladder and several other organs. It is important to remember, however, that these factors increase a person's risk but do not always "cause" the disease. Many people with one or more risk factors never develop cancer, while others with this disease have no known risk factors. It is important, however, to know about risk factors so that appropriate action can be taken, such as changing a health behavior or being monitored closely for a potential cancer. The following are some important risk factors for cancer:

1. Tobacco use
2. A high fat diet
3. Obesity
4. Ultraviolet radiation from the sun
5. Alcohol consumption in large quantities
6. Excessive radiation exposure from x-rays
7. Environmental exposure to chemicals
8. Hormone replacement therapy of estrogen has been linked to breast and uterine cancer
9. Family history of certain types of cancer

Can Cancer be Prevented?
All cancers caused by cigarette smoking and heavy use of alcohol could be prevented completely.

The chances of getting skin cancer can be lowered by staying in the shade as much as you can, wearing a hat and shirt when you are in the sun, and using sunscreen.
We know that our diet is linked to some types of cancer, although the exact reasons are not yet clear. The best advice is to eat a lot of fresh fruits and vegetables and whole grains and to cut down on high fat foods.

There are tests called screening examinations that adults should have in order to find cancer early. If cancer is found early, it can often be cured.

What are the Symptoms of Cancer?
Cancers can cause some general (non specific) symptoms. They include unexplained weight loss, fever, fatigue and pain.

In addition to the general symptoms, there are seven common symptoms that could lead to a diagnosis of cancer.

1. A change in bowel habits or bladder function.
   Chronic constipation, diarrhea, or a change in the size of the stool may indicate colon cancer. Pain with urination, blood in the urine, or change in bladder function could be related to bladder or prostate cancer. Any changes in bladder or bowel function should be reported to your doctor.
2. Sores that do not heal.
3. Unusual bleeding or discharge.
   Unusual bleeding can occur in early or advanced cancer. Blood in the sputum is a sign of lung cancer. Blood in the stool could be a sign of colon cancer. Cancer of the uterus or cervix can cause vaginal bleeding. Blood in the urine is a sign of possible bladder of kidney cancer.
4. Thickening or lump in the breast or other parts of the body.
   These lumps are usually painless initially. Do not ignore any new lump just because there is no pain. Remember, often pain occurs during the late stages of cancers when they damage the surrounding structures.
5. Indigestion or difficulty swallowing.
   These symptoms may indicate cancer of the throat, esophagus or stomach.
6. Recent change in a wart or mole.
   A change in color, loss of borders, or an increase in size should be reported to your doctor without delay.
7. A nagging cough or hoarseness.
   A persistent cough that does not go away can be a sign of lung cancer. Hoarseness can be a sign of cancer of the larynx or thyroid.

How is Cancer Diagnosed?
The appearance of a lump, results of blood tests and information from scans can often give a very good indication whether a lump is cancerous. However, it is necessary to obtain tissue samples from the lump for laboratory testing to be 100% sure. This procedure is called a biopsy.

Once a cancer is diagnosed, an evaluation will be made to determine the extent (stage) of the cancer.

How is Cancer Staged?
Staging is the process of describing the extent of the disease or the spread of cancer from the site of origin. Staging is essential in determining the choice of therapy and assessing prognosis. A cancer's stage is based on information about the primary tumor's size and location in the body and whether or not it has spread to other areas of the body. A number of different staging systems are currently being used to classify tumor. The TNM staging system assesses tumors in three ways: extent of the primary tumor (T) absence or presence of regional lymph node involvement (N) and absence or presence of distant metastases (M). The other commonly used staging system is:

1. Stage I Cancer limited to tissue or organ of origin
2. Stage II Limited, local spread of cancer
3. Stage III Extensive local and regional spread of cancer
4. Stage IV Metastases to any distant part of the body

What Terms are Used to Describe Cancer Treatment?

1. Proven treatment: Refers to evidence-based or accepted medical treatments. These have been tested following a strict set of guidelines and found to be safe and effective.
2. Research or investigational treatments: These are still being studied in a clinical trial. Clinical trials are research projects that determine whether a new treatment is effective and safe for patients. Before a drug or other treatment can be used regularly to treat patients, it is studied and tested carefully, first in laboratory test tubes, and then in animals. After these studies are completed and the therapy is found safe and promising, it is tested to see if it helps patients. After careful testing with patients shows that the drug or other treatment is safe and effective, only then it will be approved and become part of the standard mainstream collection of proven therapies.
3. Complementary therapy: Refers to supportive methods that are used to complement or add to mainstream treatments. They do not cure disease, rather they may help control symptoms of cancer, relieve side effects of standard cancer therapy, or to improve a patient's sense of well-being. Examples include meditation to reduce stress, peppermint tea for nausea and acupuncture for chronic back pain. Others include massage therapy, yoga, aromatherapy, music therapy, prayer, spiritual practices and tai chi.
4. Alternative treatments: They are promoted as cancer cures in the place of standard therapy. They are unproven because they have not been scientifically tested, or were tested and found to be ineffective. If used instead of evidence-based treatment, the patient may suffer because

• The therapy itself is harmful
• The therapy is costly
• The patient may lose the opportunity to benefit from standard treatment

Examples include:

1. Antineoplastons
2. Gerson Method
3. Shark Cartilage
4. Jason Winters Tea
5. Vitamin C
6. Tahitian Noni

For those with access to the internet, a very useful website on alternative treatment is www.quackwatch.com

What are the Goals of Cancer Treatment?
The primary goal of cancer treatment is to render the patient free of disease clinically and pathologically with the intent to return their life expectancy to that of healthy individuals of the same age and sex. In other words, to cure the patient! When a cure is not possible, the secondary goal is to maintain the patient's quality of life as well as functional status. In cases where a cure or prolonged survival is very low, therapy is administered to relieve symptoms caused by the cancer. This therapy is referred to as palliative therapy.

How is Cancer Treated?
Cancer treatment varies by the patient's age, sex, underlying health conditions, history of previous treatment as well as the type and stage of the cancer. These factors determine the most appropriate therapy for the patient and the patient's cancer. Treatment options may include:

1. Surgery
2. Radiation
3. Chemotherapy
4. Hormonal Therapy
5. Immunotherapy

Surgery used to be the only method of treating cancer. However, over the last 50 years or so, the other modes of treating cancer have rapidly progressed. Today, most solid tumors, even very early cancers are treated by more that one modality. The treatment of cancer has now evolved into a multidisciplinary approach, where a group of different specialists, namely, surgeons, radiation oncologist, medical oncologist, pathologist, etc. get together to plan out the treatment of each cancer patient, which of the modalities to use and how to combine them for the optimal benefit of the patient.

Some Healthy Tips

• Schedule annual medical examinations and cancer prevention screenings.
• Eat a well-balanced, high-fiber, low fat diet.
• Exercise at least 3 - 5 times a week with 30 minutes of light to moderate activity.
• Maintain your ideal body weight.
• Do not smoke or use other tobacco products.
• Avoid secondhand smoke.
• Drink alcohol in moderation.
• Drink at least eight 8-oz. glasses of water each day.
• Protect your skin from the sun by wearing sunscreen.

Dr Goh Kiang Hua
Consultant Surgeon