Cancer: What is it?

Cancer is a disease where abnormal cells divide without control, and usually form a lump (called a tumour) as their numbers increase. Cancer cells can invade nearby tissues and can spread through the bloodstream and lymphatic systems to other parts of the body.

Cancer cases on the rise in Singapore

According to the Singapore Cancer Society, during the period from 2017 to 2021, an average of 46 people are diagnosed with cancer daily, with 16 people dying from it every day.

Although 1 in 4 people may develop cancer in their lifetime*, the good news is, with early detection and treatment, it is possible to have better clinical / management outcomes.

Top cancers affecting Singaporean men and women (from 2017 to 2021)


​No. of cases


No. of cases





​Colon & Rectum


​Colorectal & Rectum






​Lymphoid Neoplasms


​Corpus Uteri (Uterus)




Lymphoid Neoplasms


​Non-Melanoma Skin


​Ovary & Fallopian Tube




​Non-Melanoma Skin






​Myeloid Neoplasms








​Cervix Uteri


* Source: Singapore Cancer Registry Annual Report 2021

Common cancers by gender

Lung cancer (24.8% of cancer deaths in males) and breast cancer (17.2% of cancer deaths in females) had the highest mortality rates in males and females respectively from 2017 to 2021.

The three most frequent incident cancers (2017 to 2021) are:

  • Males - prostate (16.8% of all cancers diagnosed in males), colorectal (16.3%), lung (13.5%)

  • Females - breast (29.7% of all cancers diagnosed in females), colorectal (12.9%), lung (7.9%)

During this 5-year period (from 2017 to 2021), 41,126 males and 42,876 females were diagnosed with cancer, with 16,103 males and 13,419 females dying from it.

Some cancer risk factors are within your control while some are not

The majority of cancer cases are sporadic, i.e. the disease is not inherited. By pure chance, many cases of "common" cancers such as breast, colon and lung cancers can appear to run in a family. Your personal risk depends on factors such as your age, family history of cancer and your tendency to inherit cancer genes. These are beyond your control. Other risk factors that are within our control are not genetic. These include our lifestyle, diet, smoking and environmental exposure. We must work to reduce or prevent these risk factors.

Prevention and early detection of cancer

Although great advances have been made in the treatment of cancer, the impact on survival rates has been incremental rather than dramatic. Many cancer patients are also diagnosed relatively late, at which stage their treatment options are often severely limited. Prevention and early detection of cancer are therefore key strategies in cancer control efforts. You must be responsible for your own health – only you hold the key to your well-being.

Ref: H24

Check out our comprehensive list of cancer articles:

Rise of Colorectal Cancer in Young Adults

Breast Cancer: What Puts You at Risk

Breast Cancer Screening: Your Best Protection

Tips to Keep Your Breasts Healthy

Prostate Cancer: All You Need to Know

Nose Cancer: Signs, Diagnosis and Treatment

Liver Cancer: Causes, Symptoms, Treatment

Lymphoma Cancer: First Signs, Types, Treatment

Endometrial Cancer: Risk Factors, Symptoms, Treatment and Prevention

Ovarian Cancer: Causes, Symptoms, Treatment and Prevention

Cervical Cancer: Symptoms, Screening and How to Prevent

Stomach Cancer (Gastric Cancer): Symptoms and Treatment

Thyroid Cancer: Types, Symptoms and Treatment

Multiple Myeloma (Bone Marrow Cancer): Causes, Symptoms, Treatment

Skin Cancer: Types, Symptoms, Treatment and Prevention

Cancer Diet: Top Foods to Eat and Avoid When Undergoing Treatment