Welsh Cancer Intelligence and Surveillance Unit (WCISU)

Data Providing Organisation:
Welsh Cancer Intelligence & Surveillance Unit (WCISU)

Data Providing Type:
Registry data



The Welsh Cancer Intelligence & Surveillance Unit (WCISU) is the National Cancer Registry for Wales and its primary role is to record, store and report on all incidence of cancer for the resident population of Wales wherever they are treated. Cancer registration in Wales began almost five decades ago and today’s electronic database which holds records going back to 1972 contains in the region of 686,000 records.

Data Collection Method

WCISU collects data about occurrences of cancer in Welsh residents via direct or indirect submissions from Welsh Hospitals.

Data Highlights

Staging of malignant melanoma (ICD 10 code C43), breast (C50), colorectal (C18-C20) and cervix (C53) started in 2001 since this was when we started receiving pathological information. Staging for all other cancers started in 2010.

Treatment information started in 1995.

Caution is advised in interpreting trends over time since there have been various revisions of coding cancer site. ICD8, ICD9 and (currently) ICD10 have been in operation through the years of data supplied. We have mapped historical data (pre-1995) to ICD10 but there may be some loss of accuracy of coding due to this.

WCISU release the dataset annually and the SAIL anonymised version is updated accordingly.

Access Requirements

As a restricted dataset, that requires the agreement of the data provider in addition to our standard Information Governance procedure.

More Information

See the WCISU website for more information and to view their published reports.


Approximately 686,000 records

Data Level

Individual person

Data Years

1972 – present

SAIL Schema