Cancer Registration Statistics, England 2020

Cancer registration is the systematic collection of data about cancer and tumour diagnoses. In England, this data collection is managed by the National Disease Registration Service (NDRS) in NHS Digital. Every year, the NDRS collects information on over 275,000 diagnoses of cancer, including patient details, as well as detailed data about the type of cancer, how advanced it is and the treatment the patient receives.

Data are submitted to the NDRS from a range of healthcare providers and other services (for example, histopathology and haematology services, radiotherapy departments, screening services and general practitioners). The National Cancer Registration and Analysis Service (NCRAS), which is a part of NDRS, then uses these multiple sources to build a comprehensive picture of cancer incidence in England, as well as other detailed analysis and interpretations covering the entire cancer pathway on all patients in England. For more information, please see the Data Resources Profile for NCRAS.

The quality and accuracy of the data are validated and processed to ensure that they are consistent and to a high standard. Once all the expected records for any one incidence year have been received and validated, NCRAS takes a snapshot of the dataset, which provides a single, consistent source of cancer registrations. Cancer incidence for 2020 was created from a snapshot taken on 6 October 2022, for the period January to December 2020. The snapshot will vary year on year due to the dynamic nature of registration data:

• new cancer diagnoses will be registered which can include new “late” registrations after cancer incidence has been published for that year
• cancer records can be amended, for example the site code of a record can be modified when more accurate information becomes available
• cancer records can be cancelled (although this is uncommon)
• A less common reason for changes to historical data is a patient exercising their right to opt-out of the cancer registration datasets.

The mortality data is provided by the Office for National Statistics from their annual mortality registration files.

The gap between the diagnosis counts that were first published for a registration year and the most recent cancer incidence figures has varied considerably over time. Over the 44-year period reported, differences between what has previously been published and the current number of registrations (refreshed in 2022) for each year average less than 5% (Figure 14).

The figures for numbers and rates of “all cancer” in this release refer to all malignant neoplasms which include International Classification of Diseases: ICD-10 codes of C00 to C97, excluding NMSC (ICD-10 C44). Although common, the available figures for NMSC before 2013 are known to be underestimates and unreliable for comparison purposes over time. This is because previously there has been variation in the policies and practices for the recording of NMSC. Since 2013, a “first NMSC tumour per patient” methodology has been used which more consistently reflects the incidence of NMSC.

Any regional differences in benign, uncertain and unknown neoplasms should be interpreted with caution. There is known historical variation in the way these tumours were recorded across the country.

The most recent five years of registered cancer diagnoses may be revised to reflect the results of extra tests that happen while a patient is being treated. Although the estimates of counts and rates for previous years may alter, these changes will be small. After five years have elapsed, it is unusual to see these changes occurring.

The methodology documentation contains important information on:

• the strengths and limitations of the data and how it compares with related data
• uses and users of the data
• how the output was created
• the quality of the output including the accuracy of the data.

Table 7 shows the site definitions used in the estimates of cancer incidence by stage at diagnosis.

Table 7: Cancer site and group definitions by ICD-10 revision 5 code

Notes:

• Staging systems are often valid for particular combinations of the cancer site and morphologies (subtypes that describe the individual forms and structures of the cancer).
• Some cancers come from a stageable site but have a morphology that means the cancer cannot be staged; these cancers are called “unstageable”.
• Some cancers come from a stageable site and have a morphology that means they could be staged but some other vital information is not available. These cancers are described as having missing data.
• The UK and Ireland Association of Cancer Registries Performance Indicator for early stage includes primary peritoneal carcinomas in the Ovary and Fallopian tube group – these have not been included in this report.