paywalled: Comparability of stage data in cancer registries in six countries: lessons from the international cancer benchmarking partnership - Walters - International Journal of Cancer - Wiley Online Library

 
Comparability of stage data in cancer registries in six countries: lessons from the international cancer benchmarking partnership 

Abstract

The International Cancer Benchmarking Partnership is investigating cancer survival differences between six high-income nations using population-based cancer registry data. Differences in overall survival are often explained by differences in the stage at diagnosis and stage-specific survival. Comparing stage at diagnosis using cancer registry data is challenging because of different regional practices in defining stage, despite the existence of international staging classifications such as TNM. This paper describes how stage data may be reconciled for international analysis. Population-based cancer registry data were collected for 2.4 million adults diagnosed with colorectal, lung, breast (women) or ovarian cancer during 1995-2007 in Australia, Canada, Denmark, Norway, Sweden and the United Kingdom. The stage data received were coded to a variety of international systems, including the TNM classification, Dukes' for colorectal cancer, FIGO for ovarian cancer, and to national 'localised, regional, distant” categorisations. To optimise comparability for analysis, a rigorous and repeatable process was defined to produce a final stage variable for each patient. An algorithm was also defined to map TNM, Dukes' and FIGO to a “localised, regional, distant” categorisation. We recommend how stage data should be recorded and processed to optimise comparability in population-based international comparisons of stage-specific cancer outcomes. The process we describe to produce comparable stage data forms a benchmark for future research. The algorithm to convert between TNM and a “localised, regional, distant” categorisation should be valuable for international studies, until global consensus is achieved to adhere to a single staging system like TNM.

Abstract: Which staging system to use for gynaecological cancers: a survey with recommendations for practice in the UK

Aims
There are two commonly used staging systems for gynaecological cancers, namely Federation Internationale de Gynecologie et d'Obstetrique (FIGO) and TNM. The authors wished to ascertain which staging system is most commonly used in dealing with gynaecological cancers in the UK.
Methods
The authors undertook a survey among participants in the National Gynaecological Pathology EQA scheme to investigate whether gynaecological pathologists in the UK use FIGO or TNM staging in their routine reporting of gynaecological cancers.
Results
There were 105 respondents out of 278 participants (38%). Of the analysed results, a majority of respondents (64%) use FIGO staging, while 32% use both FIGO and TNM. 80% of respondents stated that their multidisciplinary team meeting uses FIGO staging, while 18% use both FIGO and TNM. Only an extremely small minority of pathologists and multidisciplinary team meetings use TNM alone. A survey of members of the British Gynaecological Cancer Society revealed similar findings.
Conclusions
Since FIGO and TNM are not always equivalent, and there may be confusion when more than one staging system is used, it is recommended that FIGO staging be used for gynaecological cancers. The survey revealed support for the use of TNM, as well as FIGO, only for cervical cancer, since FIGO does not take the lymph node status into account. Given the prevalent practice in the UK, the British Association of Gynaecological Pathologists, British Gynaecological Cancer Society and gynaecological clinical reference group of the National Cancer Intelligence Network recommend that FIGO staging be used for gynaecological cancers with recording of the lymph node status for cervical cancer. This may be done by providing a TNM stage for this cancer type only or by recording the lymph-node status at the multidisciplinary team meeting.