National Bowel Cancer Screening Program monitoring report 2026

Note: Terms in bold within definitions are defined elsewhere in the glossary.

Aboriginal and/or Torres Strait Islander: A person of Aboriginal and/or Torres Strait Islander descent who identifies as an Aboriginal and/or Torres Strait Islander. See also Indigenous.

adenocarcinoma: A cancer that began in a glandular epithelial cell (see epithelium).

adenoma (adenomatous polyp): A benign tumour that arises from epithelial cells (see epithelium). All adenomas have malignant potential. Adenomas in the rectum or colon have a higher chance of developing into cancer (see adenocarcinoma) than adenomas in most other organs. An adenoma can be classified from highest risk (advanced) to lowest risk (diminutive).

age-specific rate: The number of cases occurring in each specified age group by the corresponding population in the same age group, expressed as ‘per 100,000 people’.

age-standardised rate (ASR): A rate derived by removing the influence of age when comparing populations with different age structures. This is usually necessary as the rates of many diseases vary strongly (usually increasing) with age. The age structures of the different populations are converted to the same ‘standard’ structure, which allows disease rates to be compared.

asymptomatic: Describes being without symptoms.

benign: Describes non-cancerous tumours that may grow larger but do not spread to other parts of the body. Not malignant.

bowel (colorectal) cancer: A cancer definition that comprises both cancer of the colon and cancer of the rectum.

cancer death: A death where the underlying cause of death is indicated as cancer. People with cancer who die of other causes are not counted in the mortality statistics in this publication.

cancer (malignant neoplasm): A large range of diseases whose common feature is that some of the body’s cells become defective and begin to multiply out of control. These cells can invade and damage the area around them and can also spread to other parts of the body through the circulatory and lymphatic systems to cause further damage.

colonoscopy: A diagnostic assessment procedure to examine the bowel using a special scope (colonoscope), usually carried out in a hospital or day clinic.

conditional relative survival: The probability of surviving a given number of years, provided that an individual has already survived a specified amount of time after diagnosis (usually 5 or 10 years). Compare with relative survival.

crude rate: The number of events over a specified period (for example, a year) divided by the total population. The crude rate (for participation, attendance and follow‑up) is the proportion of people who have proceeded to a key point on the screening pathway (at the date of the data extraction) out of those eligible to proceed to that point.

The crude proportions will generally underestimate the true proportions of the population that participated in the National Bowel Cancer Screening Program. This is because, at any point in time, there are members of the population who are eligible to proceed to the next point on the screening pathway but who have not yet had time to do so. Similarly, there is a time lag between when a person with a positive iFOBT result is referred for a colonoscopy and when they can have the procedure.

defer: Describes the action of an invitee who would like to participate in the National Bowel Cancer Screening Program but is unable to do so at this time. Such invitees will be contacted once the nominated deferral period has elapsed. Compare with opt out.

disability-adjusted life year (DALY): A year of healthy life lost, either through premature death or equivalently through living with disability due to illness or injury. It is the basic unit used in burden of disease and injury estimates.

eligible population: People who can request a screening kit from the register but are not automatically sent a kit. This includes people aged 45–49 who are registered on a green Medicare card or a Department of Veterans’ Affairs gold card. See also target population.

epithelium: The tissue lining the outer layer of the body, the digestive tract and other hollow organs and structures.

false negative: A screening test result that incorrectly indicates a person does not have a marker for the condition being tested when they do have the condition. Not all screening tests are completely accurate, so false negative results cannot be discounted. Further, with an iFOBT, if a polyp, adenoma, or cancer is not bleeding at the time of the test, it may be missed by the screening test.

false positive: A screening test result that incorrectly indicates that a person has the marker being tested when they do not have the condition. As iFOBTs detect blood in stool (which may be caused by a number of conditions), a false positive finding for bowel cancer may still detect other non‑bowel cancer conditions, or precancerous polyps or adenomas.

histopathology: The microscopic study of the structure and composition of tissues and associated disease.

immunochemical faecal occult blood test (iFOBT): immunochemical faecal occult blood test – a self-administered test to detect blood in bowel motions, but not bowel cancer itself. The iFOBT is analysed by a pathology laboratory, and results forwarded to the participant and primary health care practitioner (if nominated). The 2-sample screening kits can have an overall adequacy rating of:

• Expired: the kit was returned after the expiry date of the sample tubes
• Unsatisfactory: the kit was received greater than 28 days from the first sample date
• Not received: the kit was returned without the sample tubes
• Spoiled / Damaged: both sample tubes in the returned kit were spoiled or damaged

These first 4 adequacy ratings are given an overall result of No result. The final potential adequacy rating is:

Correctly completed: the sample tubes were not judged in the above categories overall.

Overall results of the correctly completed kits are then categorised into:

• Positive: at least one sample was positive (≥ 20 µg Haemoglobin per gram faeces) for occult blood, regardless of the other sample
• Negative: both samples were negative for occult blood
• Inconclusive: one sample was negative, and the other sample was Spoiled/Damaged or Not received, or both samples were negative. but the kit was received at the lab greater than 14 days since the first sample was taken.

Positive and negative overall results are used in positivity calculations. No result and Inconclusive results are resent a replacement kit by the pathology laboratory.

incidence: The number of new cases (of an illness or event, and so on) occurring during a given period, usually 1 year. Compare with prevalence.

Indigenous: A person of Aboriginal and/or Torres Strait Islander descent who identifies as Aboriginal and/or Torres Strait Islander. See also Aboriginal and/or Torres Strait Islander.

interval cancer: A bowel cancer that is diagnosed after completion of a negative screening episode and before the next screening examination or within 24 months of a negative screening episode, whichever comes first.

invitee: A person invited to participate in the National Bowel Cancer Screening Program.

lymph node: A mass of lymphatic tissue, often bean‑shaped, that produces adaptive immune system cells and through which lymphatic fluid filters. These nodes are located throughout the body.

malignant: Describes tumours with the capacity to spread to surrounding tissue or to other sites in the body.

metastasis: The process by which cancerous cells are transferred (or spread) from one part of the body to another; for example, via the lymphatic system or the bloodstream.

morbidity: Ill health in an individual, or the level of ill health in a population or group.

mortality: The number of deaths occurring during a given period.

new cancer case: A person who has a new cancer diagnosed for the first time. One person may have more than one cancer and therefore may be counted more than once in incidence statistics if it is decided that the additional cancers are not of the same origin. This decision is based on a series of principles, set out in more detail in a publication by Jensen et al. (1991).

non-valid address: A non-valid address may be a result of the NCSR not recognising a current postal address, or a return to sender flag is currently recorded against the invitee and their given address.

opt out: Describes what invitees do who advise that they do not wish to participate in the National Bowel Cancer Screening Program, now or in the future. Invitees who opt out will not be contacted again. Invitees may elect to opt back in at a later date.

participant: A person who has agreed to participate in the National Bowel Cancer Screening Program by returning a completed iFOBT kit and participant details form.

polyp: A small growth of colon tissue that protrudes into the colonic or rectal lumen. Polyps are usually asymptomatic, but sometimes cause visible rectal bleeding and, rarely, other symptoms. Most polyps are benign. Adenomatous polyps are more likely to become malignant than other types of polyps.

polypectomy: The removal of a polyp or adenoma.

positive predictive value: Proportion of people with a positive iFOBT screen who have adenomas or cancer detected at colonoscopy and confirmed by histopathology.

prevalence: The total number of people alive at a specific date who have been diagnosed with a particular disease (such as cancer) within a defined period.

primary health‑care practitioner (PHCP): A general practitioner or other primary health‑care provider. This may include remote health clinics or specialists providing general practitioner services.

prognosis: The likely outcome of an illness.

radiation therapy: The treatment of disease with any type of radiation, most commonly with ionising radiation, such as X‑rays, beta rays and gamma rays.

relative survival: A measure of the average survival experience of a population of people diagnosed with cancer, relative to the ‘average’ Australian of the same sex and age, at a specified interval after diagnosis (usually 5 or 10 years). A 5-year relative survival figure of 100% means that the cancer has no impact on the person’s chance of still being alive 5 years after diagnosis, whereas a figure of 50% means that the cancer has halved that chance.

screening: Repeated testing, at regular intervals, of asymptomatic people to detect a medical condition at an earlier stage than would otherwise be the case. Screening tests are not diagnostic (for example, see false positive, false negative, and positive predictive value); therefore, people who receive a positive screening result require further assessment and diagnosis to determine whether they have the disease or risk marker being screened for.

skipping a round: As of November 2019, people who are potentially eligible for the National Bowel Cancer Screening Program but who have had a recent colonoscopy (within the last 2 years) are notified that they will skip a round of the immunochemical faecal occult blood test (iFOBT), rather than being invited to participate.

stage: The extent of a cancer in the body. Staging is usually based on the size of the tumour, whether lymph nodes contain cancer, and whether the cancer has spread from the original site to other parts of the body (undergone metastasis).

symptom: Any evidence of disease apparent to the patient. For the purposes of this report, symptoms can include visible rectal bleeding, change in bowel habit, bowel obstruction or anaemia.

target population: People who are actively targeted by the National Bowel Cancer Screening Program. This includes people aged 50–74 registered on a green Medicare card or a Department of Veterans’ Affairs gold card. See also eligible population.

tumour: An abnormal growth of tissue. Can be benign (not a cancer) or malignant (cancer).

underlying cause of death: The disease or injury that initiated the train of events leading directly to death, or the circumstances of the accident or violence that produced the fatal injury.

valid results: iFOBT results that are classified as either positive or negative. Inconclusive results are excluded.

Years lived with disability (YLD): A measure of the years of what could have been a healthy life but were instead spent in states of less than full health. YLD represent non-fatal burden.

Years of life lost (YLL): Years of life lost due to premature death, defined as dying before the global ideal life span at the age of death. YLL represent fatal burden.