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Glossary of Cancer Statistics

Cancer Incidence Rates

Cancer Mortality Rates

Cancer Survival Statistics

Cancer Prevalence Statistics

Lifetime Risk of Developing or Dying of Cancer

Glossary of Cancer Statistics

Below you will find a brief description of the different types of cancer statistics. For more detailed definitions, please use the section tabs to go to the specific statistic.

  • Incidence is the number of newly diagnosed cases during a specific time period
  • Mortality is the number of deaths during a specific time period
  • Survival is the proportion of patients alive at some point subsequent to the diagnosis of their cancer
  • Prevalence is new and pre-existing cases for people alive on a certain date
  • Lifetime Risk is the probability of developing or dying of cancer

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Cancer Incidence Rates

A cancer incidence rate is the number of new cancers of a specific site/type occurring in a specified population during a year, usually expressed as the number of cancers per 100,000 population at risk. That is,

Incidence rate = (New cancers / Population) × 100,000

The numerator of the incidence rate is the number of new cancers; the denominator is the size of the population. The number of new cancers may include multiple primary cancers occurring in one patient. The primary site reported is the site of origin and not the metastatic site. In general, the incidence rate would not include recurrences. The population used depends on the rate to be calculated. For cancer sites that occur in only one sex, the sex-specific population (e.g., females for cervical cancer) is used.

An age-adjusted rate is a weighted average of the age-specific rates, where the weights are the proportions of persons in the corresponding age groups of a standard population. The potential confounding effect of age is reduced when comparing age-adjusted rates computed using the same standard population.

Find published reports and research tools for calculating Incidence Statistics.

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Cancer Mortality Rates

A cancer mortality rate is the number of deaths, with cancer as the underlying cause of death, occurring in a specified population during a year. Cancer mortality is usually expressed as the number of deaths due to cancer per 100,000 population. That is,

Mortality Rate = (Cancer Deaths / Population) × 100,000

The numerator of the mortality rate is the number of deaths; the denominator is the size of the population. The population used depends on the rate to be calculated. For cancer sites that occur in only one sex, the sex-specific population (e.g., females for cervical cancer) is used. The mortality rate can be computed for a given cancer site or for all cancers combined.

Find published reports and research tools for calculating Mortality Statistics.

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Cancer Survival Statistics

Cancer survival statistics are typically expressed as the proportion of patients alive at some point subsequent to the diagnosis of their cancer. Relative survival is an estimate of the percentage of patients who would be expected to survive the effects of their cancer. Observed survival is the actual percentage of patients still alive at some specified time after diagnosis of cancer. Survival considers deaths from all causes, cancer or otherwise. Overview of Population-based Cancer Survival Statistics contains a more detailed description and information on the interpretation of survival statistics.

Find published reports and research tools for calculating Survival Statistics.

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Cancer Prevalence Statistics

Cancer prevalence is defined as the number or percent of people alive on a certain date in a population who previously had a diagnosis of the disease. It includes new (incidence) and pre-existing cases, and is a function of both past incidence and survival. Information on prevalence can be used for health planning, resource allocation, and an estimate of cancer survivorship. Overview of Cancer Prevalence contains a description of the types of and methodology for calculating prevalence statistics.

Find published reports and research tools for calculating Prevalence Statistics.

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Lifetime Risk of Developing or Dying of Cancer

Lifetime and age-conditional risk estimates of developing cancer provide a useful summary of the current cancer risk and how this risk compares with earlier periods and among select subgroups of society. These reported estimates have the potential to promote early detection efforts, to increase cancer awareness, and to serve as an aid in study planning.

Statistical models are used to compute the probability of developing or dying of cancer from birth or conditional on a certain age. The development of this statistical methodology is described on the Statistical Research and Applications Branch Web site.

Find published reports and research tools for calculating Lifetime Risk Statistics.

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