[Practical significance of the 6 level neck classification in cancers of the aerodigestive tract].

Lymph node metastases are one of the main reasons of treatment failure in head and neck cancer. Thus, knowledge of lymphatic system anatomy and routs of spreading the metastases in particular primary tumor localisation is of great practical importance. Typical sites of neck metastases in larynx and tonsil cancer were presented. The neck lymphatic system classification according to American Academy of Otolaryngology--Head and Neck Surgery from 1991 was used. The most often site of metastases in larynx cancer was the II and III level, in tongue and floor of mouth cancer--level I and II and in nasopharynx malignancies--level II and V respectively. Knowledge of the neck regions with elevated risk of harbouring metastases was important not only during the surgery but as well before planning of the selective or elective radiotherapy.