What is TNM? ! TNM is a system for classifying malignant tumours ! It is a cancer staging system, which describes the extent of a person's cancer ! Most types of cancer have TNM designations, but some do not1 ! Most medical facilities use this system as their main method for cancer reporting1 1. National Cancer Institute, Cancer Staging, 2010 How does the TNM system work? The 3 parameters of the TNM system1: A number is added to each letter to indicate1: T = extent of the tumour the size or extent of N = the extent of spread the primary tumour to the lymph nodes M = presence of distant the extent of cancer spread metastases 1. National Cancer Institute, Cancer Staging, 2010 T = extent of primary tumour T is classified as follows:1 Tx: Primary tumour cannot be evaluated | T0: No evidence of primary tumour Tis: Carcinoma in situ (CIS)2 | T1, T2, T3, T4: Size and/or extent of the primary tumour T0 organ T1 T2 T3 local tissues 1. National Cancer Institute, Cancer Staging, 2010 2. CIS – abnormal cells are present but have not spread to neighbouring tissue; although not cancer, CIS may become cancer and is sometimes called pre-invasive cancer N = extent of spread to lymph nodes N is classified as follows1: Nx: Regional lymph nodes cannot be evaluated | N0: No local lymph node involvement N1: Tumour has spread to local lymph nodes | N2, N3: Involvement of local and distant lymph nodes (number of lymph nodes and/or extent of spread) N0 N1 distant nodes local nodes 1. National Cancer Institute, Cancer Staging, 2010 N2 M = presence of distant metastases M is classified as follows1: Mx: Distant metastasis cannot be evaluated | M0: No distant metastasis M1: Distant metastasis is present M0 M1 Mx ? lung bone liver 1. National Cancer Institute, Cancer Staging, 2010