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

Cancer Treat Rev. 2017 Mar;54:110-121. doi: 10.1016/j.ctrv.2017.02.003. Epub 2017 Feb 16.

Abstract

Purpose: To review the current knowledge on radiotherapy associated olfactory dysfunction among head and neck cancer (HNC) patients.

Methods: 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.

Results: Two hundred and twenty-nine papers were screened and 23 met inclusion criteria.

Conclusions: 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.

Keywords: Head and neck cancer; Odor detection; Odor discrimination; Odor recognition; Olfaction; Olfactory dysfunction; Radiotherapy; Smell alterations.

Publication types

  • Review
  • Systematic Review

MeSH terms

  • Dose-Response Relationship, Radiation
  • Head and Neck Neoplasms / radiotherapy*
  • Humans
  • Olfaction Disorders / etiology*
  • Radiotherapy / adverse effects*