Background: Patients with head and neck cancers (HNCs) are at increased risk of experiencing malnutrition, which is associated with poor outcomes. Advances in the treatment of HNCs have resulted in improved outcomes that are associated with severe toxic oral side effects, placing patients at an even greater risk of malnutrition. Prophylactic placement of percutaneous endoscopic gastrostomy (PEG) tubes before treatment may be beneficial in patients with HNC, especially those undergoing more intense treatment regimens. PEG tube placement, however, is not without risks. Methods: A comprehensive review of the literature was conducted. Results: Systematic evidence assessing both the benefits and harm associated with prophylactic PEG tube placement in patients undergoing treatment for HNC is weak, and benefits and harm have not been established. Conclusions: More research is necessary to inform physician behavior on whether prophylactic PEG tube placement is warranted in the treatment of HNC. © 2011 American Society for Parenteral and Enteral Nutrition.