Colon Cancer (FOB) Test

The at-home FOB (Faecal Occult Blood) test gives you a rapid indication of your gastrointestinal condition aiding the detection of several gastrointestinal diseases that in their early stages may have no visible symptoms including colon cancer, ulcers, polyps, colitis, diverticulitis, and fissures.

Currently, the traditional guaiac (a chemical substance from guaiacum trees) based screenings lack sensitivity and specificity, and they also involve dietary and medicinal restrictions prior to testing, unlike FOB rapid tests.

Occult blood means nonvisible blood in the faeces that could be a sign of a gastrointestinal disease not accompanied by readily discernible symptoms. Early detection of FOB can enable you to seek further medical advice or adopt healthier lifestyle regimes for early-stage diseases that could prevent more severe gastrointestinal damage or control the condition.

This rapid two-step lateral flow immunoassay test uses a specimen collection tube inclusive of extraction buffer and a chromatographic test cassette to detect levels of faecal occult blood above 50 ng/mL for self-testing and is mailed directly to you.

▶ COLON CANCER (FOB) SYMPTOMS:

Monitoring your FOB levels on a regular basis can prevent asymptomatic diseases from going undetected and gastrointestinal conditions from becoming worse. Reasons for using this test include:

• Family history of gastrointestinal diseases
• Nutritional issues; poor absorption
• Irregular or painful bowel movements
• Stomach cramps or discomfort
• Prolonged lack of appetite
• Frequent nausea or vomiting
• General fatigue
• Variety of digestive issues

▶ HOW IT WORKS:

The FOB rapid test detects low levels of FOB qualitatively and a double antibody sandwich assay is used. The test cassette membrane is precoated in an anti-Haemoglobin antibody covering the test line region (T) which the FOB in the specimen reacts with. The mixture migrates upwards by capillary action, reacting with the anti-Haemoglobin antibody and generating a coloured line. Two coloured lines on the cassette in the C (Control) and T (test) regions indicate a positive result and a valid test result.

Blood in your stool means there is bleeding somewhere in your digestive tract. Sometimes very small amounts can only be detected by a Faecal Occult Test and sometimes it may be visible on toilet tissue or in the toilet after a bowel movement. Bleeding that occurs in the higher digestive tract may make stool specimens appear black and tarry.

Persistently high concentrations of FOB can indicate early stages of gastrointestinal disease, however a diagnosis should not be based on the results of one single lateral flow test and further medical investigation should be sought.

▶ REFERENCES:

1. https://www.medscape.com/viewarticle/854083_2
2. https://www.webmd.com/digestive-disorders/digestive-diseases-stool-testing-blood-fecal-occult-blood-test

Concentrated levels of FOB will show as a positive test result on the test region (T) of the cassette and the more intense the colour, the higher the concentration of FOB in the sample which can indicate a gastrointestinal issue or disease.

The results can then be used to seek further medical advice and to implement healthier lifestyle choices depending on the body's condition.

Over half of your blood contains plasma, which is made of water, salts, and protein, in addition to red blood cells, white blood cells, and platelets. Red blood cells (RBC) deliver oxygen from your lungs to your tissues and organs, including your gastrointestinal system.
Gastrointestinal bleeding (GI bleed) or gastrointestinal haemorrhage (GIB); means any form of bleeding in the gastrointestinal tract that locationally can be from the mouth to the rectum.

There are two main types of gastrointestinal bleeding: upper gastrointestinal bleeding and lower gastrointestinal bleeding. The diagnosis can begin with small amounts of bleeding detected in the Faecal Occult Blood Test, followed up with physical examinations, assessment of medical history, and further medical investigations to locate the area of bleeding, such as endoscopy or medical imaging tools.

Small amounts of bleeding over a long period of time may cause iron-deficiency anaemia resulting in general fatigue or mild chest pain. Other symptoms may include abdominal pain, shortness of breath, pale skin, dizziness, or fainting. In some cases, there are no symptoms and persistent small bleeds go undetected.

Significant gastrointestinal blood loss over a short time may include symptoms such as vomiting blood, bloody stools, or black tarry stools.

The causes of upper GI bleeds can include peptic ulcer disease and oesophageal varices related to liver cirrhosis and cancer, among other diseases. The causes of lower GI bleeds may include haemorrhoids, colon cancer, and a variety of inflammatory bowel diseases. Early detection can improve health conditions and may prevent serious gastrointestinal damage.

▶ REFERENCES:

1. The effectiveness of FOBT vs. FIT: A meta-analysis on colorectal cancer screening test Maryam Mousavinezhad, 1 Reza Majdzadeh,* 2 Ali Akbari Sari, 3 Alireza Delavari, 4 and Farideh Mohtasham 5 Med J Islam Repub Iran. 2016; 30: 366.
2. Effectiveness of screening for colorectal cancer with a faecal occult-blood test, in Finland J Pitkäniemi,1 2 K Seppä,1 M Hakama,1 3 O Malminiemi,4 T Palva,5 M-S Vuoristo,5 H Järvinen,6 H Paimela,7 P Pikkarainen,8 A Anttila,1 L Elovainio,1 T Hakulinen,1 S Karjalainen,9 L Pylkkänen,9 M Rautalahti,10 T Sarkeala,1 H Vertio,9 N Malila1 3 BMJ Open Gastro 2015;2:e000034. doi:10.1136/bmjgast-2015- 000034