Is TNM Staging the Most Relevant Prognostic Clinical Factor to Consider for Treatment Decisions Before and After Surgery
The tumour nodes metastasis (TNM) system is currently the most utilised staging system to predict outcome and guide the management of patients with rectal cancer. Serial changes to the system have been made over recent years with different versions being
- PDF / 269,486 Bytes
- 6 Pages / 504.567 x 720 pts Page_size
- 97 Downloads / 119 Views
Is TNM Staging the Most Relevant Prognostic Clinical Factor to Consider for Treatment Decisions Before and After Surgery? Caroline A. Young and Nicholas P. West
6.1
Introduction
The tumour nodes metastasis (TNM) staging system was devised in the 1940s–1950s by Pierre Denoix. It is an anatomical staging system which reflects the natural progression of most solid tumours: local growth and spread occurs first (T), followed by spread to regional lymph nodes (N) and finally distant metastasis (M). Numerous possible T, N and M combinations exist; therefore combinations are grouped into ‘stages’ according to prognosis. In general tumours within one stage share a similar prognosis and higher stage is associated with poorer prognosis. The TNM staging system provides a consensus framework to describe the extent of a tumour, allowing comparison of data from different countries and over time and defines groups of
C.A. Young, BMBCh, MA N.P. West, PhD, FRCPath (*) Pathology and Tumour Biology, Leeds Institute of Cancer and Pathology, University of Leeds, Leeds, UK e-mail: [email protected]
patients within clinical trials. Prognostic staging information informs treatment decisions, i.e. decisions regarding neoadjuvant therapy; the type, extent and timing of surgery; adjuvant therapy; intensity of follow-up; and discussions with patients. The American Joint Committee on Cancer (AJCC) and the TNM Committee of the Union for International Cancer Control (UICC) periodically update the TNM manual to reflect new evidence from the literature and national cancer registries.
6.2
NM Staging of Rectal T Cancer
Although rectal cancer has many features that distinguish it from colon cancer, the two share a common basic TNM staging system. The current version is TNM 8. However, various international guidelines recommend using different versions of TNM, e.g. the United Kingdom currently mandates reporting according to TNM 5 [10]. In order to accurately compare data between countries and over time, it is therefore important not only to record the TNM stage of rectal cancers but also the version of TNM used for staging.
© Springer-Verlag Berlin Heidelberg 2018 V. Valentini et al. (eds.), Multidisciplinary Management of Rectal Cancer, https://doi.org/10.1007/978-3-319-43217-5_6
45
C.A. Young and N.P. West
46
6.3
omparison of TNM Versions C 4, 5, 6 and 7
TNM versions 4, 5, 6 and 7 differ markedly in their definitions of deposits of tumour within the mesorectal fat and under which category (T or N) they should be coded. TNM 4 states that tumour deposits should be considered as regional lymph node metastasis (N). TNM 5 refines this definition and considers only tumour deposits greater than 3 mm in diameter as regional lymph node metastasis (N), whilst those equal to or less than 3 mm are considered as discontinuous extensions of the tumour (T). In contrast, TNM 6 considers tumour deposits with smooth outlines as involved lymph nodes (N) and those with irregular contours to represent venous invasion and to be coded under the
Data Loading...
