Classifications

The diagnostic identification of solid tumours in adults is primarily determined by the ICD-10 disease code in the CNCR data. A more precise identification of cancer is determined by its morphological type, biological behaviour and degree of differentiation according to ICD-O-3. The TNM classification describes the extent of the disease.

International Classification of Diseases, 10th Revision (ICD-10)

The ICD-10 has been in force in the Czech Republic since 1 January 1994 (CZSO Communication No. 495 of 18 December 2003 on the publication of the ICD-10, No. 160/2003 Coll.). This classification serves as a basic description of cancer diagnosis [1]. During the development of the CNCR, the ICD 8th revision (until 1978) and 9th revision (until 1993) were successively used in the CNCR; these records were later converted to ICD-10 in the CNCR data (2014 update).

International Classification of Diseases for Oncology, 3rd edition (ICD-O-3)

MKN-O-3 has been in force in the Czech Republic since 1 January 2005 (CZSO Communication No. 49 of 17 January 2005, No. 11/2005 Coll.). MKN-O-3 is a dual classification with coding systems for both topography and morphology. The topographical code describes the site of origin of the tumour and uses the same three- and four-digit categories (codes). This allows a higher specificity for coding non-malignant tumours than in ICD-10. The morphological code describes the cell type making up the tumour, its biological activity (describing the tumour's characteristics) and its degree of differentiation (grade) from the surrounding tissue. It also allows detailed identification of all cancer diagnoses [2]. Detailed morphology has been in the CNCR data only since 1984, and the records correspond to the validity of the ICD-O editions (first edition until 1993, second edition from 1994 to 2004, third edition from 2005 to 2018, and the revised ICD-O-3.2 edition since 2019).

TNM classification of malignant tumours (TNM)

The TNM classification describes the anatomical extent of the primary tumour using the following three components: T – the extent of the primary tumour, N – absence or presence and extent of regional lymph node metastases, and M – absence or presence of distant metastases. Disease stage is derived based on clinical and postoperative T, N and M. TNM classification is used almost exclusively for solid tumours [3]. During its development, the TNM classification of the CNCR has been successively used in the 2nd revision (until 1981), 3rd revision (1982-1994), 4th revision (1995–2000), 5th revision (2001–2004), 6th revision (2005–2010), 7th revision (2011–2018), and currently the 8th edition, which has been valid in the CNCR data since 2019. TNM entries in the CNCR data correspond to the validity of the classification editions, but they are generally not convertible to higher versions of the TNM classification.

References

  1. Institute of Health Information and Statistics of the Czech Republic, International Statistical Classification of Diseases and Associated Health Problems, current version ICD-10. Available (in Czech language only) from: http://www.uzis.cz/katalog/klasifikace/mkn.
  2. Institute of Health Information and Statistics of the Czech Republic, ICD-0-3 International Statistical Classification of Diseases for Oncology 2004, 3rd edition (Czech version), ISBN: 80-7280-373-5. Available (in Czech language only) from: https://www.uzis.cz/publikace/mkn-3-mezinarodni-statisticka-klasifikace-nemoci-pro-onkologii-2004-3-vydani-ceska-verze.
  3. Institute of Health Information and Statistics of the Czech Republic, TNM Classification of Malignant Neoplasms, 7th edition 2011, ISBN: 978-80-904259-6-5. Available (in Czech language only) from: https://www.uzis.cz/publikace/tnm-klasifikace-zhoubnych-novotvaru-7-vydani-original-2011.