Mastication in health-related quality of life in patients treated for oral cancer: A systematic review.

INTRODUCTION: Treatment for oral cancer can impair oral functions such as mastication, which may negatively affect quality of life (QoL). In this review, an overview is provided of masticatory ability in patients treated for oral cancer. METHODS: The PubMed (MEDLINE), Embase and Cochrane databases were systematically searched for scientific literature on masticatory ability in relation to QoL in patients treated for oral cancer. Studies were included when oral cancer treatment was provided, and the University of Washington Quality of Life (UW-QoL) questionnaire was used. Risk of bias (MINORS) was independently assessed by two authors. RESULTS: The PubMed (MEDLINE), Embase and Cochrane search yielded 575 unique records of which 111 were assessed full text, and 27 studies were included. The UW-QoL mastication scores ranged from 31.9 to 97.4. There was a wide variety in methodology, patient groups, tumour site, treatment and assessment moment, to such a degree that outcome scores are difficult to compare. CONCLUSION: The wide variety in studies exploring health-related QoL in relation to mastication in oral cancer patients prevents the identification of possible relations between treatment, masticatory ability and QoL. Our findings underline the limitations in currently available literature and indicate the necessity for more comparable research.