Pitfalls of the tnm classification of head and neck tumors

Any TNM system has to be a reproducible description for the anatomic extent of the tumor. In addition, the TNM should reflect the biology of the disease in a specific site in cancer patients at a specific time in the Life history of the cancer. A modified TNM classification for the head and neck cancers is proposed considering available data on: (i) survival rate vs level of involvement; (ii) lymphatic drainage patterns; (iii) embryological development of the neck lymphatics. The modified TNM definitions contain the old 'T','M' and new 'N1', 'N2', 'N3' and 'M1(lymph)' descriptions. The involvement of the supraclaviclar lymph nodes is described by 'M1(lymph)' since the biological significance is that of a distant metastases.