Self-reported and objective taste and smell evaluation in treatment-naive solid tumour patients

Background Taste and smell abnormalities (TSA) commonly occur in cancer and are associated with anorexia, early satiety, malnutrition, weight loss and reduced quality of life. A recent study found a high TSA prevalence in newly diagnosed cancer patients before treatment. This suggests that TSA may originate from the tumour itself. No previous study has examined TSA, both subjectively and objectively, in newly diagnosed, treatment-naive cancer patients. This study aimed to address this gap. Methods This prospective observational study recruited consecutive, newly diagnosed, treatment-naive patients with solid tumours at Radiation Oncology Out-patients. Self-reported taste and smell changes since becoming ill were evaluated using modified Taste and Smell Survey, and objective taste and smell tests were conducted using 'Sniffin' Sticks Olfactory Test (R) and Burghart Taste Strips (R). Nutritional status was assessed with abridged Patient-Generated Subjective Global Assessment. Results Thirty completed the study. Seventy-four per cent had at least one TSA. Taste changes and/or abnormalities were more prevalent than smell, and subjective taste changes more common than objective abnormalities. Although less common, smell abnormalities impacted quality of life more. TSA characteristics were heterogeneous. Forty-seven per cent were at malnutrition risk. No association was found between TSA and nutritional status. Conclusions Over two thirds had at least one TSA and almost half were at malnutrition risk. Self-reported TSA included changes in taste and smell perception, and most commonly persistent bad taste. This study demonstrated the complexity of TSA assessment and the prevalence, severity and impact of these and related symptoms in treatment-naive cancer patients.