LifeCare Primary Care Doctor

1 February, 2024


In a healthy person, body cells grow and multiply to replace old or damaged cells.

However, when the abnormal or damaged cells continue to grow and multiply, they form abnormal clumps of tissue called tumours, which can be cancerous (malignant) or noncancerous (benign).

Cancerous cells disrupt the normal function and affect the behaviour of the normal cells, molecules and blood vessels near the tumour. With this, it can easily lead to the growth of tumours and the spreading of cancerous cells to the surrounding tissues, then migrating (metastasize) to distant parts of the body to form more tumours.

Early Detection Is Important!

In certain cases, some patients may remain asymptomatic or may neglect the early signs and symptoms of cancer.

In fact, delay in detection provides the opportunity for cancer to spread without any medical intervention. By the time the patient seeks medical help, chances are that it may be already too late to treat or recover.

How Can We Detect Cancer Early?

Clinical application of tumour markers can be broadly classified into 4 groups: Screening and early detection, diagnostic confirmation, prognosis and prediction of therapeutic response and monitoring disease and recurrence.

Indeed, tumour markers by cells include a variety of substances like cell surface antigens, cytoplasmic proteins, enzymes, hormones, oncofetal antigens, receptors, oncogenes and their products. It is usually produced by the cancer cells or other cells in the body in response to the presence of cancer.

Which Tumour Markers To Test?

In Malaysia, there are five most common cancers which are:

Breast Cancer

Colorectal Cancer

Lung Cancer

Nasopharyngeal Cancer

Liver Cancer

In correlation to the most common cancer in Malaysia, there are a few tumour markers widely used for detection of cancers.

CEA (Carcinoembryonic antigen)

  • A protein that is present in the blood of most patients with colorectal cancer.
  • May also be present in cancers of the pancreas, breast, ovary, or lung.
  • Non-cancerous conditions: cirrhosis, hepatitis, inflammatory bowel disease, peptic ulcer disease, or inflammation of the gallbladder (cholecystitis).

CA 125 (Cancer Antigen 125)​

  • A protein produced by the surface layer of ovarian cancer cells.

CA 19-9 (Carbohydrate antigen 19-9)​

  • Pancreatic cancer, bladder cancer, stomach cancer and gallbladder cancer.
  • Non-cancerous conditions: thyroid disease, rheumatoid arthritis, inflammatory bowel system or pancreas.

CA 15-3 (Cancer antigen 15-3)

  • Widely used for breast cancer.
  • Also detect lung, colon, pancreatic, ovarian and breast cancer (benign), ovarian disease, endometriosis and hepatitis.
  • High levels can sometimes occur in women who do not have cancer.

PSA (Prostate Specific Antigen)

  • Specific to prostate cancer
  • Can happen in benign prostatic hyperplasia (BPH ), acute bacterial infection in the prostate glands

AFP (Alpha-fetoprotein)

  • A protein is produced during the first three months of foetal development. Then it will drop dramatically when a baby is 1 year old and the levels are very low in the body of a healthy adult.
  • Usually high in liver cancer or hepatocellular carcinoma.
  • Also can be germ cell tumours, Hodgkin’s disease, lymphoma and kidney cancer.

Limits of tumour marker tests​

  • Tumour markers may be elevated in cancer patients, yet sometimes the increase can also occur in patients with non-cancerous tumours or a normal person.
  • Tumour marker tests are not perfect. It should correlate to clinical history, examinations, imaging and pathology study should be done for confirmation of diagnosis.