This page covers the terms we use in cancer statistics reports. See the end of the page for definitions of cancer site and type, and links to BC government administrative boundary information.
The age of the patient (in completed years) at the time of diagnosis or death.
The number of new cases of cancer or cancer deaths during the year, expressed as a rate per 100,000 persons in a given age group.
The number of new cases of cancer or cancer deaths per 100,000 that would have occurred in the standard population (2021 Canadian population) if the actual age-specific rates observed in a given population had prevailed in the standard population.
Relative survival that has been statistically adjusted to account for differences in the age distribution between populations, using a standard population (the International Cancer Survival Standard (ICSS) weights), so that survival can be compared fairly over time or between groups.
A summary measure of the average yearly change in incidence or mortality rates over a specified period.
Network of cancer clinics, affiliated with BC Cancer, that provide cancer care in the community.
The number of new cancer cases or cancer deaths in a population during a specified period, divided by the total number of people in that population over a given period, usually expressed per 100,000 people, without adjusting for age.
Survival rate in which only deaths from the disease are counted.
International Classification of Diseases, Tenth Revision.
The International Classification of Childhood Cancer, Third Edition (ICCC-3): The classification of childhood cancers is based primarily on tumor morphology and primary site, with greater emphasis on morphology compared to adult cancer classification, which places more emphasis on primary site
The newly diagnosed cancer cases within a population at risk over a specific period of time. A person may be counted more than once if diagnosed with multiple primary cancers.
The probability of developing or dying from cancer over the course of a lifetime.
The number of deaths attributed to a particular type of cancer that occurred during the year.
Included are deaths of patients diagnosed in earlier years, persons with a new diagnosis during the year, and patients for whom a diagnosis of cancer is made only after death.
Survival rate in which deaths from any cause are counted.
The number of people in a defined population who are alive at a specified point in time and who have ever been diagnosed with cancer (newly or previously).
- Limited duration prevalence: The number of people alive on a specified date who were diagnosed with cancer within a defined recent period (for example, within the last 5, 10, or 20 years).
- Unlimited duration prevalence: The number of people alive on a specified date who have ever been diagnosed with cancer, regardless of how long ago they were diagnosed. If a person has multiple diagnoses of the same cancer type, only the first diagnosis is counted.
- The BC Cancer dashboard reports 1‑, 5‑, 10‑, and 20‑year limited-duration prevalence, as well as unlimited-duration prevalence.
- For example, a patient diagnosed with breast cancer in 2006 and lung cancer in 2021 who is still alive on January 1, 2025, would be included in the 5‑ and 10‑year limited-duration all-cancer prevalence based on the more recent lung cancer diagnosis, and in the 20‑year limited-duration prevalence based on the earlier breast cancer diagnosis. Because both diagnoses occurred more than one year prior to the index date, the patient would not be included in the 1‑year limited-duration prevalence.
- They would also be counted in the unlimited-duration prevalence, as this measure includes all individuals who have ever been diagnosed with cancer and are alive on the index date. The lung cancer diagnosis would not contribute separately to the 20‑year, or unlimited-duration all-cancer prevalence, as individuals are counted based on their earlier breast cancer diagnosis.
- For site-specific estimates, the breast cancer diagnosis would contribute to the 20‑year limited-duration and unlimited-duration prevalence for breast cancer. In contrast, the lung cancer diagnosis would contribute to the 5‑year, 10‑year, 20-year limited-duration and unlimited-duration prevalence estimates for lung cancer.
The proportion of people in a defined population who are alive at a specified point in time and have been diagnosed with cancer, usually expressed as a percentage or per 100,000 population.
The number of estimated new cancer cases expected to occur in the future, based on incidence trends and population projections.
The proportion of cancer patients who received radiation therapy within a specified time period.
Cancer patients receiving some level of service at a BC Cancer centre or Community Oncology clinic (e.g. seen by a BC Cancer oncologist; cases registered with the BC Cancer pharmacy for drug reimbursement).
A theoretical or benchmark group of people with a fixed, known age distribution. It is used as a statistical baseline to adjust and compare incidence or mortality rates across different groups.
The ratio of the observed number of cancer cases in a population to the number of cases that would be expected based on a reference population, adjusted for age (and sometimes sex), used to compare incidence between regions.
The ratio of the observed number of cancer deaths in a population to the number of deaths that would be expected based on a reference population, adjusted for age (and sometimes sex), used to compare mortality between regions.
The classification of cancer based on tumor characteristics, lymph node involvement, and metastatic spread based on TNM Classification of Malignant Tumours as assessed at the time of initial diagnosis.
A simplified grouping of detailed TNM categories into broader stages (for example, stages I–IV) to summarize how far the cancer has spread and to support consistent reporting and comparison.
Relative survival estimates that have been statistically smoothed over time to reduce random year-to-year variation and highlight underlying long-term trends. For more details, view
Methodology for the Survival Estimates.
Cancer surveillance includes the collection of data, and the review, analysis and dissemination of findings on incidence (new cases), prevalence, morbidity, survival and mortality.
Proportion of people alive at a given time after diagnosis (e.g. 5 year survival rate)
Elapsed time between diagnosis and death.
Two or more independent primary malignancies diagnosed in the same patient within a period of six months
TNM ensures unified procedures in the general method of classification by anatomical extent of disease. Classification by stages facilitates communication of exact unequivocal information on a malignant neoplasm. The rules of classification and division by stages will be changed in connection with new results in diagnostics and therapy.
The proportion of people diagnosed with cancer who are still alive a specified number of years after diagnosis (for example, five years), regardless of whether they are cancer free.
