Bleeding after bowel movements and painful swelling around the anus are symptoms of this sickness.
Are these caused by haemorrhoids, more commonly known as piles?
That would be a good guess, especially since haemorrhoidal disease is the most common colorectal condition here.
These abnormal swollen veins in the anal canal, formed after too much pressure has been placed on them, are estimated to affect about one in three of the population.
But the same symptoms are shared by the second most common - but much less known - non-cancerous colorectal condition here called anal fistula.
This is an abnormal channel that forms between the anal canal and the skin surface of the buttock, caused by an infection within an anal gland. Such glands produce secretions to lubricate the anal canal so stool can pass smoothly.
These two ailments are agonising but unlikely to be fatal.
However, these same symptoms can also be caused by colorectal cancer - abnormal growths in the colon (large intestine) and rectum (the last part of the large intestine that stores stool).
That is the most common cancer in Singapore - and it can kill.
Every year between 2007 and 2011, an average of 1,692 people here were diagnosed with the disease and about 700 died.
Some people may be so embarrassed about having soreness down south that they dismiss it and delay seeking help.
But sitting on the sickness will not make it vanish. Even if it is not life-threatening to begin with, it can worsen and lead to complications.
When your life is at stake, there is really no time to waste.
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