Our bodies are made up of cells which constantly divide and regenerate to make new cells. It is not fully understood why, but when abnormal cells keep dividing they eventually form a lump of tissue called a tumour.
Not all tumours are cancerous. Benign tumours may grow in size but do not spread to other parts of the body unlike malignant tumours which have the potential to spread.

Prostate cancer means there are cancer cells inside the prostate that have formed a malignant tumour. Prostate cancer is the third most common cancer among men in Singapore.
The stages of prostate cancer: localised, locally-advanced, and metastatic.
After a cancer is diagnosed it is staged. Stages are used to convey the size and degree of spread of the cancer.
Localised cancer
The tumour is contained or "localised" in the prostate. The cancer is in the very early stages, and the tumour is often too small to be felt during a prostate check.

Locally advanced
The tumour has started to break through the wall of the prostate, and the cancer cells may be in the nearby tubes that produce semen or around the bladder or the rectum. This is called "locally-advanced cancer" because the tumour has grown immediately outside the prostate but has not spread to other parts of the body.

Metastatic disease
Prostate cancer can spread to the lymph nodes or bones and even organs such as the liver, lungs, and brain. This spread of cancer cells throughout the body is called metastasis.
Prostate cancer can sometimes spread to the immune glands (lymph nodes) of the body. This is called node-positive disease rather than metastatic disease. At this stage of cancer, curative treatment can still be achieved with robot assisted radical prostatectomy or radiotherapy.
If cancer has spread to the bones or other organs treatment is usually in the form of hormonal therapy.
