WHO EMRO - Noncommunicable diseases

Noncommunicable diseases

Cancer

Cancer registry

Disease registers are part of the surveillance system for several diseases, but they have been more important, and successful, for cancer than for any other condition. This is because of the serious nature of most cancers, which means that except in a few societies without access to medical care, patients will almost always present for diagnosis and treatment. This has permitted the development and use of cancer registries, particularly population-based registries, which relate the incident cancer cases to a defined population at risk.

The population-based cancer registry collects data on every person with cancer in a defined population, usually comprising people resident in a well-defined geographical region. The cooperation of the medical profession and health care services is vital to the success of cancer registration. The population-based cancer registry provides incidence rates and the emphasis is on epidemiology and public health.

A major source of information and advice about population-based cancer registries and international data from such registries is the International Agency for Research on Cancer (IARC), a part of WHO. Located in Lyon, France, IARC should be called upon to assist in any planned development or reorganization of a cancer registry.

The emphasis of a cancer registry should be on the quality of the data collected, rather than on the quantity. Some of the most successful and productive registries collect only a very limited amount of data for each patient. Registries in developing countries should collect only the basic information common to all registries. This includes subject identification (including age and sex), ethnicity, incidence date, site and histology of the tumour, and the most valid basis of diagnosis. Other items, which are extremely useful, include the extent of disease (stage) and disease outcome for survival.

The establishment of a population-based cancer registry is highly desirable in the development of a national cancer control programme. Such registries are useful in the context of documenting cancer patterns in a given region/country, in measuring the cancer burden and in studying survival from cancer as well as in evaluating trends in the incidence of cancers over time. Thus, they are valuable for the evaluation of national cancer control programmes. Hospital-based information systems provide valuable sources of information regarding methods of diagnosis, stage distribution, treatment methods, response to treatment, and survival, although accurate information on cancer incidence is unobtainable because of case referral and population coverage issues.