The Get Data Out programme routinely publishes cancer statistics produced by NHS E (previously PHE and NHS D) in a consistent table, called the Get Data Out (GDO) table. This table collects patients into groups with common characteristics, and then publishes information such as incidence, treatment rates, survival and Routes to Diagnosis for these groups.

This document sets out the definitions of the cohort and groups for the Get Data Out tables for the 2023 release of data on liver and biliary tract cancer between 2013 and 2020.

Liver and biliary tract tumours cohort

The cohort of liver and biliary tract used for Get Data Out is all tumours coded to C22, C23, C24, D015, D376, or D134 in ICD 10. These ICD 10 codes cover all primary tumours of liver and intrahepatic bile ducts, all primary tumours of the gallbladder, and all primary tumours of the other and unspecified parts of the biliary tract.

Year

The cohort is first split by the year of diagnosis.

Tumour Type

Tumours were classified based on their site, as defined by ICD 10, into ‘Malignant liver and biliary tract’ and ‘Non-malignant liver and biliary tract’.

These groupings are defined by:

Tumour Type 2 - Site

The ‘Malignant liver and biliary tract’ group is split further by ICD 10 site into ‘Liver excluding intrahepatic cholangiocarcinoma’ and ‘Biliary tract’.

These groupings are defined by:

Tumour Type 3 - Site

The ‘Biliary tract’ group is further split by site into ‘Gallbladder’, ‘Ampulla of Vater’ and ‘Cholangiocarcinoma’.

These groupings are defined by:

Tumour Type 3 - Morphology

The ‘Liver excluding intrahepatic cholangiocarcinoma’ group is split by morphology as defined by ICD-O3 into: ‘Hepatocellular carcinoma’, ‘Other liver’, ‘Unspecified liver’, ‘Combined hepatocellular carcinoma and cholangiocarcinoma’ and ‘Hepatoblastoma’. These groupings are defined in the first table of the appendix.

Tumour Type 4

The ‘Cholangiocarcinoma’ group of ‘Biliary tract’ is further split by site in ICD 10. There is a change to the partition between 2016 and 2017 to reflect the increased use of the Perihilar/Klatskin ICD-O3 morphology code (8162). Pre 2017, the Perihilar tumours are included in the site groups listed below, and post 2017, tumours coded to the Perihilar morphology code are extracted from these groups and form a separate group of their own.

From 2013-2016, ‘Cholangiocarcinoma’ is split purely by site into:

From 2017 onwards, the ‘Cholangiocarcinoma’ group is split into ‘Intrahepatic cholangiocarcinoma’, ‘Extrahepatic/distal and other cholangiocarcinoma’ and ‘Perihilar/Klatskin cholangiocarcinoma’, based on ICD 10 site codes and ICD-O3 morphology codes. The second table in the appendix details the definitions of these groups.

Given this change in partition between 2016 and 2017, 2015-2017 and 2016-2018 combined years data containing the different definitions of intrahepatic cholangiocarcinoma should not be used.

Stage

Stage splits are provided for:

‘Hepatocellular carcinoma’ and ‘Ampulla of Vater’:

‘Gallbladder’:

‘Other liver’:

The registration of 2019 tumours were being completed during the COVID-19 pandemic. This led to reduced access to the usual data sources, and despite the registry’s best efforts a noticeable decrease in data quality in some fields. This is most commonly seen in an increase in ‘stage unknown’ tumours, and a corresponding decrease in other stage groups. This should be noted when undertaking time-series analysis on the data.

The vast majority of cases are staged in either the UICC 7 or UICC 8 system, where the recommended staging system changed from UICC 7 to UICC 8 between 2017 and 2018 diagnoses. A very small percentage of cancers (less than 1%), were staged in other systems, as reported in the known limitations page. The following table shows the percentage of cases staged in each of UICC7 and UICC8 over time.

Age

Age splits are provided for:

‘Other cholangicarcinoma’:

Stage 1-2, stage 3-4 and stage unknown ‘Hepatocellular carcinoma’ and stage 4 ‘Gallbladder’:

‘Unspecified liver’, ‘Intrahepatic cholangicarcinoma’, ‘Extrahepatic/distal cholangiocarcinoma’, ‘Extrahepatic/distal and other cholangiocarcinoma’, ‘Perihilar/Klatskin cholangicarcinoma’ and the Stage unknown group of ‘Other liver’:

Gender

Where numbers allow the data is then split into male and female.

Appendix

ICD-O3 morphology codes used in the ‘Liver’ morphology split

Cholangiocarcinoma splits - pre-2017 and 2017 onwards