Singapore Cancer Society-Cancer Q&A

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LUNG CANCER

Lung cancer occurs when normal cells, as a result of chronic irritation, become abnormal and keeps on dividing, forming more and more abnormal cells without control or order. The malignant tumours can invade & damage nearby tissues & organs. It can spread to other parts of the body such as bones, liver & brain through the lymphatic system or blood stream.

Q: How common is lung cancer in Singapore?

Lung cancer is the most common cause of death in Singaporean men & the 3rd most common cancer in women.

Q: What causes lung cancer?

Cigarette smoking. This is the major cause of lung cancer and accounts for about 90% of all lung cancer. The risk of lung cancer increases when one starts smoking at an early age, or inhales relighted half-smoked cigarettes. It also increases with the number of cigarettes smoked each day, and with the number of years of smoking. Other causes are

· Environmental tobacco smoke (or passive smoking)
· Occupational exposure to asbestos & radiation
· Contact with the processing of steel, nickel chrome & coal gas
· Atmospheric air pollution

Q: What are the symptoms of lung cancer?

They symptoms may be persistent cough, shortness of breath, blood stained sputum, chest pain, & repeated bouts of bronchitis or pneumonia.

In later stages, people may experience fatigue, weight loss, extreme shortness of breath, difficulty in swallowing and hoarseness of voice, clubbing of fingers, & symptoms of fluid being built up in the chest.

Sometimes, symptoms that seem unrelated to the lungs may actually be caused by the spread of a lung cancer.

Q: How is lung cancer diagnosed?

Lung cancer may be detected through the following tests:

· Chest x-rays
· CT scans
· Sputum test
· Removing lung tissue sample for microscopic examination through a bronchoscope or needle aspiration
· Removing fluid from the lung to check for cancer cells

Sometimes surgery is needed to diagnose lung cancer.

Q: What are the methods of treatment available for lung cancer?

Surgery, radiation therapy & chemotherapy

If the cancer is confined to the lung, surgery gives the best chance of a cure except for small cell lung cancer. Depending on the size, location, extent of the cancer, the general health of the patient & other factors, different types of surgery will be used. It is unfortunate to note that 75% of all patients are in either advanced stage or have too poor lung function for surgery.

Radiotherapy, given in 5 days a week for several weeks, is used to destroy cancer cells and to relieve pain in advanced cancer.

Chemotherapy is the treatment of choice for those with small cell lung cancer. Unfortunately, recurrences are common and only a small number are curable.

COLORECTAL CANCER (or BOWEL CANCER)

The bowel is the last part of the digestive tract, which consists of a small bowel and a large bowel. The large bowel has 2 parts, namely the colon and the rectum, hence the term colo-rectal.

When cells in the inner wall of the bowel become abnormal and divide without control or order, a tumour mass is formed. As it grows, the tumour can narrow or block the bowel. The cancer can spread through the bowel wall, and then spread to nearby lymph nodes, and finally to other parts of the body.

Q: How common is colorectal cancer?

In spore, colorectal cancer is the 2nd most common cancer, after lung cancer in male and breast cancer in female. Cancer is extremely uncommon in small intestines.

Q: What causes colorectal cancer?

As with other cancers, certain people are more likely to develop colorectal cancer. The risk increases after the age of 40 and if one is on a high fat-low fibre diet. Personal history, inflammatory bowel diseases, smoking, lack of exercise, lack of calcium in food, alcohol consumption, & family history are other risk factors associated with this disease.

Q: What are the signs & symptoms of colorectal cancer?

Early detection of colorectal cancer is important, as the chances of cure are the greatest at early stage. Medical attention should be sought if the following symptoms persist:

. Rectal bleeding or blood in the stool
. Stools that are smaller in width than usual
. Diarrhoea or constipation
. Abdominal discomfort with feeling of bloating, fullness or cramps
. Frequent gas pains
. A constant urge to pass stool
. Constant tiredness & unexplained weight loss

Q: How is colorectal cancer detected?

The diagnosis may involve digital examination by a doctor for any swelling or lump inside the anus. A stool test for occult blood is able to detect more than 70% of colorectal cancer at an early stage. A narrow tube, called a sigmoidoscope, may be used to inspect the rectum. Alternatively, a colonoscopy may be performed to inspect the entire length of the bowel, and to remove benign growths. A biopsy may be done during the sigmoidoscopy or colonoscopy for microscopic examination. At times a barium enema is done to check for abnormalities in the bowel.

To confirm the findings of these tests, further tests such as ultrasound scan and CT scan are performed.

Q: What are the treatment methods for colorectal cancer?

All the 3 conventional methods, namely surgery, chemotherapy & radiotherapy have been used on colorectal cancers.

Surgery involves the removal of that part of bowel containing the cancer as well as the lymph glands in the abdomen. The 2 open ends are then joined together. If the bowel cannot be rejoined, then an artificial opening, called a stoma, is opened onto the abdominal wall. A stoma bag is placed over the stoma to collect the bowel motions. In most cases, the colostomy is only temporary.

Chemotherapy is useful for cancer that has spread to the lymph nodes and when cancer has spread too far for surgery to be effective. It is used as palliative treatment to relieve pain rather than for cure.

Radiotherapy is recommended for rectal cancer to improve control of cancer.

Living with colostomy

Before surgery, it is necessary to be informed of the practical and personal aspects of living with a colostomy. There may also be certain food, such as high fibre food, which one has to avoid because these may give loose stools and produce wind. Having a colostomy, however, should not affect one's ability to have sexual relations.

The Spore Cancer Society has a support group under the name of "Stoma Club" for ostomates.

LIVER CANCER

The liver is formed by different types of cells; different tumours can start in any of these cell types, and these tumours could be benign or malignant.

Q: How common is liver cancer?

Worldwide, liver cancer is the 7th commonest cancer in males and the 9th commonest in females. In some parts of Asia & Africa, it is the most common type of cancer. In Singapore, it is the 4th among the most frequently occurring cancers in males.

Q: What causes liver cancer?

The exact manner in which the normal liver cells become cancerous is only partially understood. However, scientists believe that it involves damage to the DNA, and replication of cells with the same DNA error. Once this happens, it is too late to repair the damage that may eventually lead to a cancer.

Some of the risk factors are:

· Aflatoxin, which is a poisonous substance produced in a fungus which infects peanuts
· Chronic infection with hepatitis B & C viruses
· Alcohol abuse leading to scar tissue formation in the liver
· Inherited disorders that cause damage to the liver
· Certain chemicals like vinyl chloride
· Long-term use of anabolic steroids
· Drinking water contaminated with arsenic

Q: How is liver cancer diagnosed?

The signs & symptoms of liver cancer usually do not show up until the later stages. A doctor should be consulted if these problems persist:
· Anorexia or persistent lack of appetite
· Unexplained weight loss
· Increasing abdominal girth
· Persistent pain in the abdomen and around the right shoulder blade
· Sudden jaundice
· Dramatic change in the overall condition of a person with chronic hepatitis or cirrhosis
· A lump that can be felt in the area of the liver
· Enlargement of the breast in men

To confirm the diagnosis, a series of investigations that include blood tests, ultrasound, CT scan, needle biopsy, laparoscopy, angiography or MRI may be performed.

Q: How is liver cancer treated?

The treatment option depends on many factors, such as age, general health, personal preference, social circumstances, location and extent of the tumour. Generally, surgery, chemotherapy and radiation therapy are the 3 main methods of cancer treatment.

Surgery involves removal of all cancer visible to the surgeon at the time of operation. Complete removal may not be possible if the cancer is large or if several small cancers are present in different parts of the liver. People with cirrhosis are considered eligible for surgery only if their cancers are very small. Cryosurgery, that is, destruction of tumour by freezing it, has shown promise in delaying the progress of the cancer.

In chemotherapy, anticancer drugs are injected into the bloodstreams that reach all parts of the body. This makes the treatment potentially useful for cancers that have spread to other organs. Chemotherapy, however, also damages some normal cells.

The use of radiation therapy is limited because of the sensitivity of normal liver tissue to radiation.

Q: What happens after treatment?

The doctor will decide which follow up tests should be done and how often. To watch for recurrence or metastasis, abdominal CT scans and other imaging studies may be taken.

Q: Can liver cancer be prevented?

Yes, most liver cancers can be prevented by public health measures that reduce exposure to known risk factors mentioned earlier.

BREAST CANCER

The majority of breast cancer begins in the milk ducts, a small no. starts in the milk sacs or lobes. Breast cancer can easily spread to the lymph nodes in the armpit and through the blood to other parts of the body such as bones, liver, lungs & brain.

Q: What causes breast cancer?

A number of factors probably work together to trigger its growth. Breast cancer is more common in women over 45 years of age and increasing till age 65. Breast cancer is uncommon in men.

Some factors that put women at higher risk are:

. Those with a strong family history
. Women who have already had breast cancer
. Those having menses at an early age or late menopause
. Women who have never been pregnant or women having the first child after the age of 30
. Women with an apple shaped body, &
. Alcohol consumption before the age of 30.

Additional factors are low-fibre diet, tobacco use, & exposure to radiation.

Q: How could we protect ourselves against breast cancer?

To prevent breast cancer, follow a healthy lifestyle & do breast self-examination monthly. Note that 9 out of 10 breast lumps are not cancer but it is important that you seek medical opinions immediately. If detected early, breast cancer is curable.

Q: What are the screening tests available for breast cancer?

First & foremost is the mammogram. A mammogram is a low-radiation x-ray, which helps to detect cancer that cannot be felt by hands. However, not all breast cancers can be detected by mammogram alone, and further tests such as ultrasound & fine needle biopsy are needed to confirm the diagnosis. In addition, hormone tests, bone scan, chest x-ray, blood tests, and sometimes liver scan may be necessary to check whether the cancer has not spread to these areas.

Q: How are breast cancers treated?

The first treatment for early stage breast cancer is usually surgery. Before surgery, radiotherapy is usually used to reduce the size of the lump. Examination of the lymph nodes after they have been removed from the armpit will indicate whether further treatment should be considered. The surgery may involve removal of the whole breast, or just part of the breast containing the cancer. If the whole breast is removed, breast reconstruction can be done immediately or as a second procedure.

Chemotherapy is offered to some women with early breast cancer as an additional treatment to surgery, radiotherapy or both. For some cases with early breast cancers, hormones such as tamoxifen may be used as an additional treatment to reduce recurrence.

The side effects of treatment vary amongst individuals. A point to note is that removal of a breast may cause imbalance and discomfort in the neck, shoulder, chest, back, & arm muscles. Sometimes, there may be numbness in these areas due to injuries to some skin nerves. In addition, removal of the lymph nodes may slow the lymphatic flow, and as result, swelling (or lymphedema) is built up in the arm and hand.

Recovery & follow up care

Rehabilitation is a very important part of breast cancer treatment. After surgery, exercise should begin slowly, and this helps to regain strength in the arm and shoulder, as well as reduce pain and stiffness of the neck. Swelling of the arm and hand can be reduced or prevented with certain exercises, by elevating the arm, by wearing an elastic sleeve, by medication, or by a machine that compresses the arm.

The Spore Cancer Society has a support group for breast cancer patients under the name of "Reach to Recovery".

OVARIAN CANCER

Ovarian cancer is a malignant tumor in one or both ovaries. There are 4 main types of ovarian cancer; the most common type is epithelial ovarian tumor.

Q: How common is ovarian cancer in Spore?

It is the 6th most common cancer in Spore.

Q: What causes ovarian cancer?

The cause of ovarian cancer is unknown, although there are some factors which seem to put women at a higher risk. Some of the risk factors are:

. Women with few pregnancies or who have never been pregnant
. Women who have never been on contraceptive pills
. Family history of the disease
. High fatty diet, and
. Mumps virus
Ovarian cancer is more common in the Caucasian.

Q: How is ovarian cancer diagnosed?

The diagnosis may be difficult, however, the following symptoms may be present:

. Feeling of discomfort, bloated feeling in the abdomen
. Change in bowel habits
. Flatulence & indigestion
. Symptoms related to the kidney or bladder
. Abnormal vaginal bleeding
. Pain in the abdomen
. Enlarged abdomen from the tumour, and
. Loss of weight

During physical examination, a doctor may be able to detect a lump or fluid in the abdomen. Additional diagnostic methods include blood tests, routine chest & abdominal x-rays, ultrasound of the lower abdomen, and barium enema. The gold standard, however, is a laparotomy.

Q: What are the treatments available for ovarian cancer?

These include a laparotomy, chemotherapy and radiotherapy.

A laparatomy is an operation in the abdomen. Tissue samples are removed and sent for laboratory investigation. The results of these biopsies will show the extent and the type of the disease. Very often, the ovaries and fallopian tubes, the entire uterus and the surrounding organs are also removed.

Chemotherapy is almost always recommended for ovarian cancer in advanced stage. This involves the use of anticancer drugs to destroy and stop cancer cells from multiplying. Chemotherapy works best when the remaining tumour is small in amount and is usually given through an intravenous drip.

Radiotherapy is occasionally used, especially if the tumour is confined to the pelvis.

Q: What happens after one has gone through the treatment?

She may experience menopausal symptoms and therefore may require hormone replacement therapy. There may also be bowel problems. If she has symptoms of vomiting, discomfort or pain in the abdomen, then she should see a doctor immediately.

Other problems she may have after treatment are accumulation of fluid in the legs, in the abdomen and in the chest.

STOMACH CANCER

Stomach cancer is the 3rd most common cancer in the Singaporean male, and the 5th common cancer in the Singaporean female.
When cancer develops in the stomach, it may spread to other parts of the body.

Q: What causes stomach cancer?

The causes of stomach cancer are ill defined. However, some of the high risk factors are: smoking, family history, taking preserved food containing nitrites, taking smoked, salted & pickled food, infection of helicobacter pylori, atrophic gastritis, & blood group A.

Q: Does stomach cancer present any symptoms?

The symptoms are usually vague and are common to many other conditions. Some of the warning signs are: indigestion, difficulty in swallowing, vomiting, & passing black tarry stools. Having these symptoms, however, does not necessarily mean that one has a stomach cancer.

Q: Then how is stomach cancer diagnosed?

The diagnosis usually involves a physical examination, blood tests, contrast x-ray studies like a barium meal, & gastroscopy. Once a stomach cancer has been diagnosed, a CAT scan & an ultrasound scan may be done.

Q: What does the treatment of stomach cancer involve?

The choice of treatment depends on a no. of factors including age, general health, the type and size of the cancer, and whether it has spread to other parts of the body or not.

In the early stages of stomach cancer, surgery is the treatment of choice. If the cancer is more advanced, the treatment will be based with or without surgery with addition of chemotherapy or radiotherapy.

Surgery involves the removal of part or all of the stomach and local lymph nodes. In more advanced cases, where there is blockage of the flow of food through the stomach, palliative surgery is done to relieve symptoms rather than to cure the cancer. Thus surgery may involve removal of the blockage or a bypass of the blockage. It usually involves an operation but sometimes procedures can be done through the gastroscope with removal of some of the tumour with a laser.

When chemotherapy is used, its objective is to kill all cancer cells by stopping them from multiplying with the least possible damage to normal cells. Radiotherapy is seldom used for stomach cancer.

After treatment

The patient will experience some changes to the eating habits, for example, the inability to eat large meals, or discomfort when eating certain foods. The bowels may also be looser. For some, regular vitamin B injections may be necessary.

SKIN CANCER

Normally the cells of the skin divide in an orderly manner, allowing the body to grow and to heal after an injury. Sometimes for some reasons, some cells grow in an abnormal way and may grow into a lump called tumour which may be benign or malignant. A malignant tumour is made of cancer cells, and if not treated, may spread into other areas. Sometimes these cancer cells break away from the original cancer and spread to other organs to form another cancer.

Q: What causes skin cancer?

Exposure to the sun's ultraviolet rays. Common skin cancer seems to be related to a slow build up of the effects of sunlight over many years.

Q: How common is skin cancer?

It is the 7th most common cancer in both males & females in Spore.

Q: What are the signs of skin cancer?

Skin cancer takes a variety of forms. It is seldom painful and may not be ugly. If there is any unusual spot on the skin which does not go away within a couple of weeks, medical attention is necessary.

Q: Who are at a risk of getting skin cancer?

These include:
. fair skinned people who do not tan but go red in the sun
. people with red hair & blue eyes
. people with freckles or have many moles
. those who have been exposed to the sun during childhood, &
. those with family history of skin cancer

The risk may also increase if one is on certain drugs, or under UV therapy, or exposed to certain industrial chemicals.

Q: What are the tests available for screening skin cancer?

Usually this involves a biopsy under local anesthesia, or even removal of the entire spot. Further tests such as x-rays, blood tests & scans may also be done.

Q: How is skin cancer treated?

The treatment method will depend on age, general health, the type and size of the cancer, site on the body, personal preference and whether the cancer has spread to other parts of the body.

For a large cancer, a skin graft may be necessary. This involves using a layer of the skin from another part of the body. If the cancer is very small and not deep, it may be removed by freezing it.

When one is medically unfit for surgery or where surgery might be difficult or disfiguring, radiotherapy may be used. In the case of chemotherapy, the drugs may come in the form of a cream or liquid to be applied directly to the tumour, or as a tablet.

CERVICAL CANCER

Cervical cancer is the 4th most frequently occurring cancer in the female Singaporean, after breast, colon & lung cancers.

Q: What causes cervical cancer?

The exact cause of cervical cancer is still unclear. Recent studies have suggested strong association of this cancer with viral warts. Although association with genital herpes has also been reported, no direct link has been established. However, women are more likely to develop cervical cancer if they have reached menopause, become sexually active at an early age, have many sex partners, smoke cigarettes and have had a large number of pregnancies. HIV infection (or AIDS) may also cause cervical cancer.

Q: What are the signs & symptoms of cervical cancer?

Like all cancers, cervical cancer in its early stage may have no symptoms. However, a doctor should be consulted if the following problems persist:

· Bleeding after sexual intercourse
· Abnormal vaginal discharge or bleeding
· Irregular bleeding between menstrual period or after menstruation
· Unexplained weight loss

Q: How is cervical cancer detected?

The most widely used screening test for cervical cancer is PAP smear. A dramatic decrease in deaths from this disease has resulted from regular Pap smear. However, because of its dependence on the microscope & human manual screening, the accuracy of Pap smear has been limited to date. A new computer assisted method called Papnet has shown to be able to assist cytologists in the detection of cancer cells.

Apart from Pap smear, colposcopy & cone biopsy are also performed to confirm the presence of cervical cancer.

Q: What are the treatments available for cervical cancer?

In the early stage of cervical cancer, or if the cancer is limited to the cervix & upper vagina only, the entire womb will be removed. For all stages of the disease, radiotherapy is useful. Chemotherapy is usually used also to destroy the remaining cancer cells.

Q: How could cervical cancer be prevented?

Go for regular Pap smear, stop smoking if you are a smoker, and be faithful to one sex partner who should be faithful to you also.

PROSTATE CANCER

Prostate cancer is a malignant tumour of the prostate gland which is about the size of a walnut. It is located below the bladder and surrounds the top part of the urethra. The prostate produces semen and its development depends on testosterone, a male sex hormone. When cancer develops in the prostate, it may spread through the lymphatic system to other parts of the body such as the bones and lungs.

Q: How common is prostate cancer in Spore?

It is the 6th commonest cancer in the Singaporean men.

Q: What causes prostate cancer?

A definitive cause for prostate cancer has not been established, however, there are risk factors.
The risk for prostate cancer increases with age as well as an increasing number of affected relatives. The incidence is high in the Scandinavian but low in the Asian. Smokers and workers exposed to cadmium are also at a higher risk. Other risk factors include a diet high in animal fat but low in fibres, and a previous vasectomy. High circulating levels of testosterone have also been noted in those with prostate cancer.

Q: What are the signs and symptoms of prostate cancer?

Prostate cancer often does not show any symptoms, but locally extensive prostate cancer may produce obstruction of the ureteres by the primary tumour, which may lead to kidney failure. Sometimes the cancer may spread to the bones.

Q: How is prostate cancer diagnosed?

Prostate cancer may be detected through routine rectal examination, blood tests, biopsy, transrectal ultrasonography, & bone scans.

Q: What are the treatments available for prostate cancer?

If prostate cancer is detected in its early stage, usually nothing will be done about it, although sometimes a prostactomy or radical radiotherapy may be recommended.

For advanced and metastatic prostate cancer, hormone therapy is instituted as the disease is hormone sensitive. Cryosurgery, which is a controlled freezing process of the prostate gland, may also be favoured as it seems to associate with fewer complications. Occasionally, radiotherapy is used to relieve pain caused by secondary cancers in the bones or to shrink obstructions in the lymphatic or urinary systems.

NASOPHARYNGEAL CANCER (or NPC)

The nasopharynx is the space behind the mouth and nose. Many different types of tumour cells can occur in the nasopharynx.

Q: How common is Nasopharyngeal Cancer?

Nasopharyngeal Cancer (NPC) or cancer of the nose is common among adults between the ages of 35-55 years. It is the 5th most common cancer in the male Singaporean.

Q: What causes NPC?

The exact way in which the cells from the nasopharynx become cancerous is not fully understood. Unlike other squamous cell cancers of the head and neck, NPC does not appear to be linked to excessive use of tobacco or alcohol.

A few factors which are thought to predispose an individual to NPC are:

. Chinese or Asian ancestry, particularly Cantonese
. Exposure to Epstein-Barr Virus or EBV
. Consumption of salted fish during weaning or early childhood, and
. Consumption of preserved foods.

Q: What are the signs & symptoms of NPC?

About 75% of the people may have painless but enlarged lymph nodes in the neck. Other symptoms include nose bleeding, nasal obstruction, hearing problems, headache, sore throat, difficulty in swallowing, & blood stained phlegm.

Q: How is NPC diagnosed?

NPC may be detected through x-rays, CT scan or MRI, routine blood tests, & biopsy. A physical examination and evaluation of medical history are done before carrying out the tests.

Q: How is NPC treated?

The primary treatment of NPC is high dose radiation therapy. Surgery is usually reserved only for lymph nodes that fail to regress after radiation or for recurrent lymph nodes. Sometimes, chemotherapy may also be used to shrink the tumours so that they become more treatable with either radiation or surgery.