A longitudinal evaluation of smell and taste function in children with cancer during and after treatment with chemotherapy.

Smell and taste changes are bothersome treatment symptoms interfering with food intake. It remains unclear how and when children with cancer experience such changes during chemotherapy, and if the symptoms resolve after treatment. In this longitudinal study, we measured smell and taste function of 94 childhood cancer patients treated for hematological, solid, or brain malignancies. Smell and taste function were assessed using commercial Sniffin' Sticks and Taste Strips, respectively. For both tests, normative values were used to identify the presence of smell and taste abnormalities. Self-reported chemosensory and appetite changes were assessed using a questionnaire. Measurements were taken approximately 6 weeks (T0), 3 months (T1), 6 months after starting chemotherapy (T2), and 3 months after termination of chemotherapy or maintenance phase for children with acute lymphoblastic leukemia (ALL) (T3). We found that smell and taste scores did not change during active treatment (T0-2). However, approximately 20% of the patients suffered from decreased taste function according to normative values, particularly children with lymphoma or solid tumors. Changes in smell were predominantly characterized as increased rather than decreased. Self-reported changes were much more common than objectively measured, with smell changes ranging from 26 to 53% and taste changes up to 80% during treatment. After active treatment, odor threshold scores decreased in children with ALL during maintenance phase, whereas total taste scores increased in all children at T3. In summary, objectively measured smell and taste function remained stable during active treatment, while at the individual level a fairly large number of children suffered from chemosensory distortions which comprised either increased or decreased sensitivity. Individual dietary advice and coping strategies are warranted to prevent detrimental effects on food intake in children with cancer.

Taste function in children: normative values and associated factors.

BACKGROUND: Although less frequent than in adults, taste loss also occurs in childhood. "Taste Strips" are frequently used for diagnosing taste dysfunction; however, normative values are lacking for children. In this study, we will create normative values for the "Taste Strips" in children. METHODS: This cross-sectional study included 609 children aged 6-15 years. "Taste Strips" were used to determine sweet, sour, salty, and bitter taste scores by a non-forced procedure. The 10th percentile was used to distinguish normal taste function from a reduced sense of taste. Multivariable generalized linear models (GLM) were estimated to study the effect of age (group), sex, and 6-n-propylthiouracil (PROP) status on taste function. RESULTS: Taste function changed with age, allowing for a distinction of three age groups: (I) 6-7 years, (II) 8-9 years, and (III) 10-15 years. Normative values were created for the age groups and boys and girls separately. Additionally, GLM showed a significant effect of (1) age (group) on sweet, salty, bitter, and total taste scores; (2) sex on sweet, sour, and total taste scores; and (3) PROP status on total taste scores. CONCLUSIONS: This study provided normative values for the "Taste Strips" in children, highlighting age- and sex-related differences. IMPACT: Taste dysfunction can be harmful and impacts quality of life, a topic that became increasingly important since the COVID-19 pandemic. Although taste dysfunction is thought to be rare in childhood, the detrimental impact of such dysfunction might be large, as children's eating habits are strongly influenced by input from the chemical senses. Measuring taste function may elucidate the relationship between taste dysfunction and disease, fostering the development of more appropriate supportive strategies. However, adequate tools are lacking for children. Normative values of the "Taste Strips" are now available for children, which bolster the clinical utility of this test.

Taste Dysfunction in Children-A Clinical Perspective and Review of Assessment Methods.

Taste dysfunction has been associated with aging and is therefore thought to be less common in children. However, children can face medical conditions influencing their taste function. Measuring and understanding taste dysfunction in children may foster the development of treatments/interventions mitigating the detrimental effects of taste dysfunction on children's appetite and quality of life. But measuring loss of taste function requires adequate tools. This review was conducted to 1) provide an overview of etiologies (i.e., disease and iatrogenic) associated with taste dysfunction in a pediatric population; 2) to investigate which tools (psychophysical tests and questionnaires) are available to assess taste function in children; and 3) to identify what tools can be and are actually used in clinical practice. It is concluded that only a minority of available tools to assess taste function in children are readily suitable for a pediatric clinical setting. Considering the profound impact of taste dysfunction in the pediatric setting, developing, and implementing a standard taste test that is sensitive, simple, and practical to use with children is pertinent.

Smell and taste function in childhood cancer patients: a feasibility study.

PURPOSE: Chemotherapy can affect smell and taste function. This has never been investigated in childhood cancer patients during chemotherapy. The objective of this study was to determine whether psychophysical smell and taste tests are suitable for children with cancer. Taste and smell function, fungiform papillae density, and eating behavior were measured before (T1) and after (T2) a cycle of chemotherapy and compared with healthy controls. METHODS: Thirty-one childhood cancer patients treated for a hematological, solid, or brain malignancy (median age 12 years, 16 girls), and 24 healthy controls (median age: 11 years, 10 girls) participated. Smell function was measured using Sniffin' Sticks, including a threshold, discrimination, and identification test. Taste Strips were used to determine recognition thresholds for sweet, sour, salty, and bitter taste. Papillae density was investigated by counting the fungiform papillae of the anterior tongue. Eating behavior was assessed using the Behavioral Pediatrics Feeding Assessment Scale (BPFAS). RESULTS: Smell and taste function could be investigated in more than 90% of the patients, while fungiform papillae density could be determined in 61% of the patients. A significant difference in smell threshold was found between patients and controls (p = 0.001), showing lower thresholds in patients. In patients, sweet taste (p < 0.001), bitter taste (p = 0.028), and total taste function (p = 0.004) were significantly different after a cycle of chemotherapy, with higher scores at T2. CONCLUSION: The assessment of smell, taste, and fungiform papillae density is feasible in children with cancer. Results of the current study suggest that smell and taste sensitivity increased in children with cancer.

The impact of changes in taste, smell, and eating behavior in children with cancer undergoing chemotherapy: A qualitative study.

Background and aims: Taste changes are the third most common bothersome symptom during treatment in children with cancer. However, it is still unclear what the essence of these taste changes are, to what degree concomitant changes in sense of smell qualify this bothersome treatment symptom and how much of an impact these changes have on the life of children with cancer. The aim of this study was to explore characteristics of both taste and smell changes and to gain insight into the impact of these changes in children with cancer receiving chemotherapy. Methods: Semi-structured interviews were performed until data saturation was achieved in each age group (6-12, 13-17 years). This resulted in an in-depth description of taste and smell changes, including its impact on the life of 27 children with various cancer types receiving chemotherapy. Thematic analysis of interview data was performed. Results: Interview data could be grouped into three main themes, namely changes in (1) taste, (2) smell, and (3) eating behavior. As expected, most children reported experiencing taste and smell changes just after start of treatment, but changes varied greatly between children; that is, some reported changes in intensity (increased or decreased), whereas others reported different perceptions or preferences (from sweet to savory). Taste and smell changes (regardless of direction) negatively impacted quality of life, with these changes commonly described as "disappointing" or "frustrating." Interestingly, particular chemotherapeutic agents were frequently mentioned regarding taste and smell changes, prompting sensory-specific coping strategies. Children's eating behavior changed in terms of alterations in food liking and appetite, sometimes due to chemosensory changes, but children also mentioned specific medication or hospital food being responsible for their altered eating behavior. Conclusions: Both taste and smell changes are common in children with cancer. The essence of these changes varies widely, but taste and smell changes are generally considered bothersome treatment symptoms. Ways to cope with taste or smell changes specifically were described by the children warranting further research and offering the opportunity for enhancing patient-centered care.