Which way do I go? Gaining an understanding of head and neck lymphatic drainage patterns

Learning Objectives To review head and neck lymphatic drainage patterns in order to provide one with a better understanding of how to approach potential neoplastic routes of metastasis.

METHOD: Present an overview, based on review of the literature, of common potential drainage routes for spread of nasopharyngeal, oropharyngeal, and oral cavity neoplastic lesions. DISCUSSION: As nuclear medicine physicians caring for head and neck cancer patients, we are committed to providing referring clinicians with anatomical information which will help guide the care of our mutual patients. Not uncommonly, we as imagers can see what they cannot, based on physical examination and direct visualization alone. There are also times when imaged findings may not be initially obvious. In particular, this can be true regarding lymphatic drainage patterns of head and neck cancers which may include occult metastatic lymph nodes, parallel lymphatic drainage routes, and involvement of multiple sentinel lymph nodes, involving 2 or more regional basins. However, if we learn about the routes that head and neck cancers typically travel, we will be better equipped to successfully navigate the courses of potential tumor spread and more effectively uncover lesions of concern. CONCLUSION: There are typical, although not unique and often complex, lymphatic drainage patterns for each subset of head and neck cancers, based on the location and cytology of the primary lesion. Unfortunately, occult metastasis also plays a not insignificant role in the spread of disease, involving 30-40% of head and neck cancer patients. Thus, it is in the best interest of our patients that we first gain a fine grasp of the typical places to investigate for the presence of obvious pathological lymph nodes, while also understanding how to better expose more occult lesions, in the hope of finding a means of sparing patients potentially unnecessary neck dissections with associated risks for morbidity and mortality.