A systematic review of smell alterations after radiotherapy for head and neck cancer

• Published in: Cancer treatment reviews 2017-03, Vol.54, p.110-121
• Main Authors: Álvarez-Camacho, M., Gonella, S., Campbell, S., Scrimger, R.A., Wismer, W.V.
• Format: Article
• Language: English
• Subjects: Dose-Response Relationship, Radiation; Head and neck cancer; Head and Neck Neoplasms - radiotherapy; Humans; Odor detection; Odor discrimination; Odor recognition; Olfaction; Olfaction Disorders - etiology; Olfactory dysfunction; Radiotherapy; Radiotherapy - adverse effects; Smell alterations
• ISSN: 0305-7372; 1532-1967
• DOI: 10.1016/j.ctrv.2017.02.003

[Display omitted] •Publications investigating olfactory dysfunction as an explicit side effect of radiotherapy for head and neck cancer were reviewed.•Detection, identification and discrimination olfactory functions are impaired after radiotherapy.•A radiotherapy dose–effect has been calculated for odor identification and discrimination.•Future studies should explore the effect of olfactory dysfunction on weight loss and energy intake. To review the current knowledge on radiotherapy associated olfactory dysfunction among head and neck cancer (HNC) patients. A systematic review of RT-related olfactory dysfunction in HNC was performed. Searches were conducted in several databases (Medline, EMBASE, CINAHL, CAB Abstracts, SCOPUS, Proquest Dissertations and Theses, PROSPERO, ALLEBM Reviews – Cochrane DSR, ACP Journal Club, DARE, CCTR, CMR, HTA, and NHSEED). Publications investigating olfactory dysfunction as an explicit side effect of Radiotherapy (RT, or RT-chemo or RT-monoclonal antibodies) were eligible, no limits were applied. Two hundred and twenty-nine papers were screened and 23 met inclusion criteria. Odor detection, identification and discrimination are olfactory functions impaired after RT for HNC. An RT dose–effect has been calculated for odor identification and odor discrimination. There were no studies of the effect of olfactory dysfunction on weight loss or energy intake among RT-treated HNC patients. To improve our understanding of RT associated olfactory dysfunction among HNC patients, future studies should include a multi-dimensional assessment of olfactory function in a longitudinal design, track other conditions affecting olfaction, assess retronasal olfactory perception, adopt validated self-report tools and explore the impact of olfactory dysfunction on the eating experience of HNC patients.