Many condition can cause rectal bleeding. It is important that you exclude a serious cause first by speaking to your doctor!  Risks symptoms for a more serious cause include having clots, blood being mixed with the stools, having lots of bleeding, bleeding frank blood, passage of mucus, increasing age(the older you are the higher your risk of bowel cancer), presence of anaemia and loss of weight

Causes include:

1. Bowel cancer – in particular a rectal cancer or cancer in the sigmoid colon

2. Polyps in the bowel – especially large ones in the rectum

3. Haemorroids – this is quite common but it is important to speak to your doctor about it and be examined throughly to exclude more serious cause

4. Inflammatory bowel disease eg proctitis, ulcerative colitis, Crohn’s disease

5. Anal fissure – usually there is a lot of pain when or after opening the bowels(but be warned : rectal cancer invading into the anal canal can also be painful)

6. Trauma to the perianal tissue

Lifetime risk of developing bowel cancer in Australia by the age of 85 years old:

1 in 10 men

1 in 14 women

Medial age at diagnosis: 70 years old

Risks in next 5 years:

30 year old person – 1 in 7000(less than the risks from a colonoscopy of perforation and serious bleeding)

40 year old person – 1 in 1200

50 year old person – 1 in 300

60 year old person – 1 in 100

70 year old person – 1in 65

80 year old person – 1 in 50

The risk is also greater for people with a family history of bowel cancer

Recently another patient in his early 40s went to see his GP for a skin lesion.  The GP suggested he has a FOBT too during the consultation. The FOBT turned out to be positive.  He subsequently had  a colonoscopy which showed a small caecal cancer. He went on to have a right hemicolectomy. Further scans have not shown any evidence of spread.

Were it not for his GP ordering the FOBT, this patient’s cancer would probably not have been detected until a few years later(usually the patient would either present with anaemia; occasionally one can get a right sided abdominal pain  from this that could be the same as an appendicitis type pain). This raises the dilemma for the all doctors  – how aggressively does one screen the patient and from what age? Also is there enough resources to do this especially in the public system?

This is a difficult question to answer for the individual.

Just last month a man in his 40s was seeing his GP for a skin problem when the GP suggested that he take the test. The faecal occult blood test came back positive – in fact, positive on all specimen. He was then referred for a colonoscopy.

On colonoscopy, a bowel cancer in the caecum was found.

He subsequently underwent a bowel resection.  The pathology showed that is was a fairly advanced cancer – with lymph glands involved. Further scans suggest the possibility of spread to the liver already..

The main difference is actually the Medicare fees – say you are referred to a specialist because you have been screened for faecal occult blood and the test has been positive. For the initial consult, the Medicare benefits(100%) for the gastroenterologist is $139.45 while for surgeons it is $79.05.  This difference is because different specialities are allowed to claim different rates for the consults and in the past, not many physicians do procedures such as endoscopy.

Also in general, surgeons tend to treat the haemorrhoids at the same time while most gastroenterologist would refer the haemorrhoids to a surgeon for treatment(eg banding of haemorrhoids)

Not all general surgeons do colonoscopies as they concentrate on their specialized fields.  But there are general surgeons too who specializes in colonoscopy.

The most important thing is to check if the endoscopist is allocating enough time to do the scope in order to have a good thorough gentle look for polyps. One can easily miss a polyp in a mucosal fold or under a pool of faeculent fluid if one does a colonoscope too quickly(eg if there are time or economic pressures)

You should always speak to the endoscopist about this. It is best for the endoscopist to allocate on average about 30minutes to do a colonoscopy.

Bowel cancer is so common (About 1 in 20 Australians will develop bowel cancer in their lifetime) and so are haemorrhoids. It is not safe to assume once symptoms is due to haemorrhoids alone. It is best that this is discussed with your general practitioner. And if there are any concerns, you should be referred to a surgeon or endoscopist.

There has certainly the cases where patients present with clear symptoms of bleeding from haemorrhoids but on colonoscopy, a bowel polyp or even bowel cancer has been found!

Faecal Occult Blood Test (FOBT)

What types of FOBT are there?

There are two main types of FOBT – namely the guaiac and immunochemical tests.

The National Bowel Cancer Screening Program uses an immunochemical FOBT called ‘Detect™’.

An immunochemical FOBT is better than a Guaiac FOBTs because they have no potential for interference by diet or medication, and are considered to be less intrusive, more reliable, more acceptable and more likely to achieve higher participation rates.

What does the test involve?

The FOBT is a simple test that can be done at home before sending it to a pathology laboratory for analysis. The test is quick, easy and painless. To increase the chances of detecting tiny amounts of blood in the bowel motion, samples are taken from two separate bowel motions. Because the test involves taking separate samples, it is not practical to do the test at a doctor’s surgery. Once both samples are collected they are returned by post to a pathology laboratory for analysis.

How accurate/effective is the test?

Like any screening test, a FOBT is not 100% accurate. However, it is currently the most well researched screening test for bowel cancer.

Because cancers and precancerous growths only bleed intermittently it is possible that the FOBT will miss one. This is why it is important to screen regularly and see a doctor if symptoms develop, regardless of the FOBT result.

Why do more than one samples need to be provided?

As cancers and precancerous growths only bleed intermittently, providing more than one samples helps to ensure a more accurate FOBT result.

Is a special diet required before collecting the samples?

No. It is not necessary to change your diet in any way.

Are there any restrictions for medication?

No. It is not necessary to avoid taking any medicines before the sample collection. The test is specific for human blood, so the test is not affected by medicines.

Are there any restrictions on when samples cannot be collected?

Yes. Samples cannot be collected if:

• it is during or within 3 days either side of a menstrual period;
• haemorrhoids (piles) are bleeding; or
• blood is present in the urine or visible in the toilet bowl – in this case contact your doctor.

What does the FOBT show?

If no significant blood is found in the samples the FOBT result is negative. People who receive a negative result should repeat a FOBT in two years. If they have or develop symptoms (or become aware of a significant family history of bowel cancer) they should see their doctor as soon as possible.

If significant levels of blood are present in the samples the FOBT result is considered positive. About one in 10 people will have a positive result. The presence of blood may be due to conditions other than cancer, such as polyps, haemorrhoids, or inflammation of the bowel, but the cause of the bleeding needs to be investigated. People with a positive FOBT result will be advised to contact their doctor to discuss the result and should then be referred for a colonoscopy.

An inconclusive or incomplete FOBT result may occur for a number of reasons, including incorrect use of the test, too much faeces in the samples, a significant delay between taking the two samples or a delay in sending the test to the pathology laboratory. The test should be repeated if so.

Reference:

National Bowel Cancer Screening Program

Note:

The second phase of the National Bowel Cancer Screening Program commenced on 1 July 2008 and will only offer testing to people turning 50, 55 or 65 years of age between January 2008 and December 2010. (the reason for this is to ensure waiting times for colonoscopy do not increase dramatically – about 10% of the FOBT are positive requring referral for colonoscopy)

If you are between those ages, please speak to your doctor about getting the screening tests done.