Are constipation and bloody stool signs of colorectal cancer?

PHOTO: Are constipation and bloody stool signs of colorectal cancer?

Warning symptoms of a potential serious illness like colorectal cancer can include bleeding during passage of stool.

Q. I am concerned about my mother who is in her mid-50s. She recently mentioned she was having constipation and there was blood in her stool when she eventually managed to move her bowels.

She also said she was having back pain. I'm not sure if it was in the kidney or liver area. Recently, she has also been more afraid of the cold than usual. Here are some details on her lifestyle.

At work, she will usually have only fruit for lunch. This is usually in the form of a fruit salad, which can include guavas, apples and pears. She returns home from work at around 7.30pm and will busy herself with household chores. She then takes a shower before sitting down for dinner at 9pm.

For dinner, she takes large portions of rice and other dishes, typically meat and vegetable from hawker stalls. She usually finishes her dinner around 10pm. She has a preference for sweetened drinks - not carbonated types, but packet drinks such as lemon tea or chrysanthemum tea. I am not sure how much water she drinks throughout the day and at work. After dinner, she will either tend to more household chores or rest for a while before sleeping at midnight.

Her last check-up about two years ago showed that everything was normal. I would like to know what is causing her constipation, blood in her stool and back pain.

Are they symptoms which are early warning signs of potential major illnesses? What are these illnesses? What are the other warning signs to look out for? Can things be corrected at this stage? What are the steps that should be taken to improve the situation and her lifestyle?

Regarding her being more afraid of the cold, is she just suffering from physical exhaustion? Who should I consult to diagnose her overall health?

I am very worried, given that it is not easy to convince her to change her habits or to take time off to see the doctor for a check-up. I would appreciate some advice on the situation.

Warning symptoms of a potential serious illness include bleeding during passage of stool, persistent abdominal pain, weight loss, vomiting and abdominal distension.

As your mother is in her mid-50s and given her recent symptoms of constipation with passage of blood in her stool, it is pertinent that she undergo evaluation to exclude the possibility of colorectal cancer.

The most appropriate test to diagnose this condition will be colonoscopy, which involves examining the large intestine using a flexible tube with a small camera inserted through the anus. Through colonoscopy, tissue samples can be obtained to check for cancer.

For the prevention of colorectal cancer, the public is encouraged to go for screening before symptoms appear to detect cancer in the early stage or even at the pre-malignant stage, where polyps can be removed to prevent cancer development.

Besides colorectal cancer, other important conditions to consider for people in your mother's age group would be diverticular disease (inflamed colon wall pouches) and ischaemia (lack of blood supply) to the bowels.

Both these conditions may not have any early warning signs, but they can be diagnosed through radiologic tests such as computed tomography scans.

Given your mother's history of cold intolerance with constipation, she should also be checked for low levels of thyroid hormone (hypothyroidism) through a blood test.

However, this condition alone will not explain her bleeding during bowel movements.

An X-ray of her spine should be performed to determine the cause of her back pain.

Before medical help can be offered to improve your mother's health, tests to arrive at a correct diagnosis should be expedited.

I would recommend that she make an appointment as soon as possible with a polyclinic doctor or general practitioner, who would be able to assess her symptoms thoroughly and recommend the appropriate tests.

For general advice on her dietary habits, I would suggest that she have three regular meals and consume her dinner earlier to allow adequate time for digestion before sleeping. She should also limit consumption of soft drinks with a high refined sugar content, which can contribute to unhealthy weight gain.

Dr Kelvin Thia
Consultant gastroenterologist at Raffles Internal Medicine Centre at Raffles Hospital

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