Taste and smell dysfunction in patients receiving chemotherapy: a review of current knowledge

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.

Nutritional Management of Oncological Symptoms: A Comprehensive Review

Throughout their experience of illness and during the course of treatment, a substantial proportion of cancer patients are prone to develop nutritional and/or metabolic disturbances. Additionally, cancer patients often encounter long-term side effects from therapies, which may lead to impaired digestion, nutrient absorption or bowel motility. Therefore, the preservation and maintenance of an optimal and balanced nutritional status are pivotal to achieving a better prognosis, increasing the tolerance and adherence to cancer therapies and improving the overall quality of life. In this context, personalized nutritional programs are essential for addressing conditions predisposing to weight loss, feeding difficulties, digestion problems and intestinal irregularity, with the goal of promoting adequate nutrient absorption and minimizing the detrimental effects of treatment regimens. The focus of this research is to examine the most common clinical conditions and metabolic changes that cancer patients may experience, including stomatitis, xerostomia, diarrhea, nausea, vomiting, dysphagia, sub-occlusion, dysgeusia, dysosmia, anorexia, and cachexia. Furthermore, we present a pragmatic example of a multidisciplinary workflow that incorporates customized recipes tailored to individual clinical scenarios, all while maintaining the hedonic value of the meals.

Effect of Regular Consumption of a Miraculin-Based Food Supplement on Taste Perception and Nutritional Status in Malnourished Cancer Patients: A Triple-Blind, Randomized, Placebo-Controlled Clinical Trial-CLINMIR Pilot Protocol

Taste disorders are common among cancer patients undergoing chemotherapy, with a prevalence ranging from 20% to 86%, persisting throughout treatment. This condition leads to reduced food consumption, increasing the risk of malnutrition. Malnutrition is associated not only with worse treatment efficacy and poor disease prognosis but also with reduced functional status and quality of life. The fruit of Synsepalum dulcificum (Daniell), commonly known as miracle berry or miracle fruit, contains miraculin, a taste-modifying protein with profound effects on taste perception. The CLINMIR Protocol is a triple-blind, randomized, placebo-controlled clinical trial designed to evaluate the regular consumption of a food supplement containing a miraculin-based novel food, dried miracle berry (DMB), on the taste perception (measured through electrogustometry) and nutritional status (evaluated through the GLIM Criteria) of malnourished cancer patients under active antineoplastic treatment. To this end, a pilot study was designed with 30 randomized patients divided into three study arms (150 mg DMB + 150 mg freeze-dried strawberries, 300 mg DMB, or placebo) for three months. Throughout the five main visits, an exhaustive assessment of different parameters susceptible to improvement through regular consumption of the miraculin-based food supplement will be conducted, including electrical and chemical taste perception, smell perception, nutritional and morphofunctional assessment, diet, quality of life, the fatty acid profile of erythrocytes, levels of inflammatory and cancer-associated cytokines, oxidative stress, antioxidant defense system, plasma metabolomics, and saliva and stool microbiota. The primary anticipated result is that malnourished cancer patients with taste distortion who consume the miraculin-based food supplement will report an improvement in food taste perception. This improvement translates into increased food intake, thereby ameliorating their nutritional status and mitigating associated risks. Additionally, the study aims to pinpoint the optimal dosage that provides maximal benefits. The protocol adheres to the SPIRIT 2013 Statement, which provides evidence-based recommendations and is widely endorsed as an international standard for trial protocols. The clinical trial protocol has been registered at the platform for Clinical Trials (NCT05486260).

Prevention of Taste Alterations in Patients with Cancer Receiving Paclitaxel- or Oxaliplatin-Based Chemotherapy-A Pilot Trial of Cannabidiol

INTRODUCTION

Taste alteration is a common adverse effect of chemotherapy. This study aimed to investigate the effect of cannabidiol (CBD) on Lean Body Mass (LBM), and taste alterations during oxaliplatin- or paclitaxel-based chemotherapy.

METHODS

LBM was estimated by bioelectrical impedance analysis (BIA), and taste perception was evaluated by a randomized sensory test of six samples: sweet, salt, and umami, all in weak and strong concentrations. Taste perceptions were scored on visual analog scales. Patients in the intervention group received oral CBD 300 mg/day for 8 days; patients in the control group did not. Patients were followed for three cycles of chemotherapy.

RESULTS

Twenty-two/ten patients (intervention/control group) were eligible. No effects on LBM were demonstrated. At baseline, the control group was able to differentiate between weak and strong saltiness and weak and strong sweetness but lost this ability after three cycles of chemotherapy. At baseline, the intervention group was unable to differentiate between the concentrations but gained the ability to significantly differentiate between weak and strong sweetness (p = 0.03) and weak and strong saltiness (p = 0.04) after three cycles of chemotherapy and treatment with CBD.

CONCLUSIONS

CBD may improve patients' ability to differentiate taste strengths during chemotherapy.

Taste loss in cancer patients: clinicians' perceptions of educational materials and diagnostic tools

PURPOSE

Cancer therapy is essential and lifesaving; however, it can have short- and long-term consequences on patients' health. Up to 87% of cancer patients report changes in taste function, yet patients report a lack of support from clinicians regarding their experience with taste loss during and following treatment. Thus, the objective of this study was to assess clinicians' knowledge and experience with managing patients with taste loss and identify potential gaps in the availability of educational materials and diagnostic tools.

METHOD

In an online survey, sixty-seven participants who identify as clinicians and practice in the United States and work with cancer patients that complain of taste problems answered questions on their knowledge and experience supporting cancer patients experiencing changes in taste function and provided their opinion on access to educational materials.

RESULTS

The current study reports gaps in participants' knowledge of taste and taste disorder terminology, with 15.4% correctly defining both taste and flavor and roughly half were familiar with specific taste disorder classifications. Over half of the participants reported not having access to adequate information to help their patients manage taste alterations. Only two-thirds of participants reported routinely asking patients if they are experiencing changes in taste function.

CONCLUSION

Clinicians' responses emphasized the need to improve access to educational materials regarding taste changes and increase the availability of information regarding management strategies. Addressing these inequities in education and improving the standard of care is the first step in improving the care for cancer patients suffering from altered taste function.

Mimicking the Biological Sense of Taste In Vitro Using a Taste Organoids-on-a-Chip System

Thanks to the gustatory system, humans can experience the flavors in foods and drinks while avoiding the intake of some harmful substances. Although great advances in the fields of biotechnology, microfluidics, and nanotechnologies have been made in recent years, this astonishing recognition system can hardly be replaced by any artificial sensors designed so far. Here, taste organoids are coupled with an extracellular potential sensor array to form a novel bioelectronic organoid and developed a taste organoids-on-a-chip system (TOS) for highly mimicking the biological sense of taste ex vivo with high stability and repeatability. The taste organoids maintain key taste receptors expression after the third passage and high cell viability during 7 days of on-chip culture. Most importantly, the TOS not only distinguishs sour, sweet, bitter, and salt stimuli with great specificity, but also recognizes varying concentrations of the stimuli through an analytical method based on the extraction of signal features and principal component analysis. It is hoped that this bioelectronic tongue can facilitate studies in food quality controls, disease modelling, and drug screening.

Chemobrain, Olfactory and Lifestyle Assessment in Onco-Geriatrics: Sex-Mediated Differences between Chemotherapy and Immunotherapy

A possible link between chemotherapy and cognitive impairment has been identified. In the literature, this condition is usually called chemobrain and can mostly affect some memory domain but can lead also to other cognitive impairments. Olfaction, which is known to be linked with cognitive domain and the nociception system, can also be affected by chemotherapy. The aim of this study was to investigate the main cognitive and olfactory abilities and the functional and nutritional state of a cohort of chemotherapy and immunotherapy onco-geriatric patients and control geriatrics subjects. Cognitive, olfactory, geriatric and nutritional assessments were performed through the Mini Mental State Examination (MMSE), Sniffin' Sticks Screening 12, G8 test and a questionnaire on the adherence of the Mediterranean diet, respectively. Our findings show a gender effect on the MMSE. Overall results indicate more pronounced impairments both at the cognitive and frailty level regardless of the type of therapy. On the other hand, the Sniffin' Sticks performances highlight a significant decrease in olfactory perception ability of subjects following immunotherapy. Significant correlations between olfactory performance and MMSE and G8 scores were also found, as well as between MMSE and G8 measures.

Taste and smell disturbances in patients with chronic oral graft vs. host disease: An observational study

Background

A common complication of allogeneic hematopoietic stem cell transplantation (alloHSCT) is chronic oral graft vs. host disease (cGvHD). Oral cGvHD may present as mucosal lesions, salivary gland dysfunction, and trismus. Moreover, taste and smell ability may be affected, but the prevalence, nature and severity of altered taste and smell function, and their impact on quality of life (QoL) are understudied.

Aim

To identify the prevalence, nature, and severity of taste and smell disturbances, their impact on QoL and to assess whether altered taste/smell ability is associated with oral mucosal cGvHD or hyposalivation.

Materials and methods

AlloHSCT recipients at least 100 days post-HSCT and referred for oral cGvHD-related oral complaints were eligible for participation in this cross-sectional study. Manifestations of oral mucosal cGvHD were scored, the (un)stimulated salivary flow was measured, and objective taste and smell ability was evaluated. Subjective taste and smell alterations, and overall and oral health (OH)-related QoL were assessed.

Results

In total, 45 patients were included, of which objective reduced taste ability (hypogeusia) was identified in 68.9%; 28.9% had reduced smell ability and 11.1% had complete loss of smell. Nevertheless, only 31.1% of patients reported severe taste alterations and 22% reported moderate taste alterations indicating that not all the patients were aware of their altered taste sense. Taste/smell disturbances were not related to oral mucosal cGvHD or hyposalivation. Most alloHSCT recipients reported a decreased OH-related QoL. However, a relation between taste/smell ability and global or OH-related QoL could not be identified.

Conclusion

Taste and smell disturbances are prevalent among alloHSCT recipients. Most patients reported a decreased OH-related QoL, but the specific impact of taste and smell disturbances remains to be elucidated.

The role of saliva in taste dysfunction among cancer patients: Mechanisms and potential treatment

Two of the highest prevalent symptoms reported by cancer patients are taste dysfunction (17.6-93%) and dry mouth/xerostomia (40.4-93%). While it has been hypothesized that reduced saliva may impair taste function, few studies investigate the co-occurrence of taste and dry mouth symptoms in cancer patients. This review provides a summary of the physiological relationship between saliva and taste, focusing on taste transduction mechanism, regulation of the taste sensitivity, and protection of taste receptor cells, including the impact of cancer treatments and malignancy on saliva function, salivary components, and the mechanisms in which it can negatively impact the taste function. Here, the authors present a scoping review of the recent literature reporting on the association between taste dysfunction and dry mouth in cancer patients, including reports of non-pharmaceutical liposomal agents or drugs taken to improve dry mouth symptoms that also assess taste dysfunction. Considering the complexities of cancer and cancer treatment, understanding the physiological relationship between saliva and taste function may provide important insight into identifying treatments for alleviating taste dysfunction and dry mouth symptoms. There are substantial research gaps given the limited studies assessing the co-occurrence of taste loss and dry mouth and inconsistencies in the assessment of these symptoms. Clinical studies examining taste dysfunction will provide a foundational groundwork that will help understand the relationship between taste and saliva. Considering the increased rates in survivorship and the significant negative impact of taste dysfunction on quality of life, more research is needed to reduce the suffering of cancer patients.

Taste alterations during neo/adjuvant chemotherapy and subsequent follow-up in breast cancer patients: a prospective single-center clinical study

PURPOSE

Dysgeusia and taste alterations (TAs) are side effects of cytotoxic chemotherapy and affect patients' quality of life; however, the prevalence, types, and duration of TAs and their potential relationship with other clinical disturbances are not well-described. Our primary aim was to prospectively evaluate the characteristics of TAs in early breast cancer (EBC) patients during (neo)adjuvant chemotherapy and up to 1 year after its completion.

METHODS

From April 2014 to June 2018, 182 EBC patients entered the study and received (neo)adjuvant chemotherapy, mostly with taxane and anthracycline-containing regimens (65% of cases). A dietitian performed TAs assessment through the Common Terminology Criteria for Adverse Event v4.0 (CTCAE) and the Chemotherapy-induced Taste Alteration Scale (CiTAS) questionnaire during chemotherapy and follow-up according to defined time points: at baseline (T0, before starting chemotherapy); at the first follow-up visit, (T1, 2 months after starting chemotherapy); at the final follow-up visit (T2, 1 week after completing chemotherapy); after that, every 3 months up to 12 months.

RESULTS

Dysgeusia was reported by 69.8% of patients at T1 and declined subsequently; salty flavor distortion was the most frequently reported TA (51.6% of cases). CiTAS was significantly different between T0 and T2 (p < 0.001). Dysgeusia occurred more frequently in patients reporting nausea, mucositis, diarrhea, and appetite modification.

CONCLUSIONS

TAs are common but transient during chemotherapy and occurred frequently with other distressing gastrointestinal side effects. The assessment of these side effects is crucial in managing EBC patients during (neo)adjuvant chemotherapy.

Individual Differences in Chemosensory Perception Amongst Cancer Patients Undergoing Chemotherapy: A Narrative Review

Chemotherapy is an aggressive form of treatment for cancer and its toxicity directly affects the eating behavior of many patients, usually by adversely affecting their sense of smell and/or taste. These sensory alterations often lead to serious nutritional deficiencies that can jeopardize the patient's recovery, and even continue to affect their lives once treatment has terminated. Importantly, however, not all patients suffer from such alterations to their chemical senses; and those who do, do not necessarily describe the side effects in quite the same way, nor suffer from them with equal intensity. The origin of these individual differences between cancer patients undergoing chemotherapy treatment has not, as yet, been studied in detail. This review is therefore designed to encourage future research that can help to address the perceptual/sensory problems (and the consequent malnutrition) identified amongst this group of patients in a more customized/personalized manner. In particular, by providing an overview of the possible causes of these large individual differences that have been reported in the literature. For this reason, in addition to the narrative bibliographic review, several possible strategies that could help to improve the chemosensory perception of food are proposed.

Oral chronic GVHD after allogeneic stem cell transplantation without total body irradiation performed at a young age

Purpose

Long-term survivors (LTSs) of allogeneic hematopoietic stem cell transplantation (allo-HCT) may experience oral long-term effects like chronic graft-versus-host disease (oral cGVHD). The aim of this study was to investigate oral cGVHD in patients treated at a young age (< 30 years) more than 5 years after allo-HCT without total body irradiation (TBI).

Methods

All 94 participants went through a semi-structured interview, and an oral examination. Diagnosis of oral cGVHD was based on the “National Institutes of Health (NIH) cGVHD diagnosis and staging consensus criteria” from 2014.

Results

Mean age at transplantation was 17.5 years (range 0.4–29.9 years), and mean time since transplantation was 16.7 years (range 6–26 years). Oral cGVHD was diagnosed in 26 (28%) of 94 LTSs. Of which 20 (21.5%) showed lichen planus-like (LPL) changes, and additionally six (6.5%) also fulfilled the diagnostic criteria of oral cGVHD since they had one or more distinctive signs and symptoms of oral cGVHD combined with definite cGVHD in another organ. No LTSs reported oral cGVHD (NIH) grade 3. There was a significant association between cGVHD in the oral cavity and cGVHD in another organ (77% vs 29%, p < 0.001). Out of 72 LTSs, who answered the questions regarding taste disturbances, 16 (22%) reported dysgeusia. No LTSs developed secondary malignancies in the oral cavity during follow-up time.

Conclusion

Oral long-term effects, such as oral cGVHD, may persist for many years after allo-HCT without TBI-conditioning in patients treated at a young age.

Nutritional Status Impairment Due to Neoadjuvant Chemotherapy Predicts Post-Radical Cystectomy Complications

Background: Radical cystectomy (RC) is the standard treatment for muscle invasive bladder cancer (MIBC). Neoadjuvant chemotherapy (NAC) is associated with improved patient survival. The impact of NAC on nutritional status is understudied, while the association between malnutrition and poor surgical outcomes is well known. This study aims to examine the association between NAC, nutritional status impairment, and post-operative morbidity. Materials and Methods: We included MIBC patients who underwent RC and received NAC from multiple academic centers in Israel. Cross-sectional imaging was used to measure the psoas muscle area and normalized it by height (smooth muscle index, SMI). Pre- and post-NAC SMI difference was calculated (represents nutritional status change). The primary outcomes were post-RC ileus, infection, and a composite outcome of any complication. Logistic regression models were fit to identify independent predictors of the outcomes. Results: Ninety-one patients were included in the study. The median SMI change was −0.71 (−1.58, −0.06) cm²/m². SMI decline was significantly higher in patients with post-RC complications (−18 vs. −203, p < 0.001). SMI change was an independent predictor of all complications, ileus, infection, and other complications. The accuracy of SMI change for predicting all complications, ileus, infection, and other complications was 0.85, 0.87, 0.75, and 0.86, respectively. Conclusions: NAC-related nutritional deterioration is associated with increased risk of complications after RC. Our results hint towards the need for nutritional intervention during NAC prior to RC.

Lactoferrin supplementation for taste and smell abnormalities among patients receiving cancer chemotherapy

PURPOSE

Taste and smell abnormalities (TSA) are common in patients receiving chemotherapy and may lead to altered nutritional intake, treatment withdrawal, and impaired quality of life. Lipid peroxidation in the oral cavity is one cause of TSA. Lactoferrin (LFN), an iron-binding salivary protein, reduces production of lipid oxidation byproducts and has been shown to reduce perception of unpleasant flavors. To assess the feasibility of LFN as a treatment for TSA, we conducted pilot investigations among patients with cancer who self-reported TSA following onset of chemotherapy. The primary objective was to assess change in subjective taste and smell perception from baseline to completion of 30 days of LFN supplementation.

METHODS

Patients were treated with 750 mg LFN daily for 30 days and followed for an additional 30 days without LFN. TSA was measured via the taste and smell questionnaire (TSQ) including taste (score 0-10), smell (score 0-6), and composite scores (0-16) (0 = no TSA) at baseline, day 30, and day 60.

RESULTS

A total of 26 patients enrolled; 19 remained on study at day 30 and 17 at day 60. Baseline mean TSQ scores were 6.5 (taste), 3.1 (smell), and 9.6 (composite). By day 30, mean composite TSQ score improved by 1.7 (p = 0.018); taste and smell improved by 0.6 (p = 0.062) and 1.1 (p = 0.042), respectively. From baseline to day 60, mean composite TSQ score improved by 3.8 (p < 0.0001); taste and smell improved by 1.9 (p = 0.001) and 1.8 (p = 0.003).

CONCLUSIONS

Further evaluation of LFN is warranted to determine its value for improving self-reported TSA among patients receiving chemotherapy.

Cyclophosphamide-Induced Inflammation of Taste Buds and Cytoprotection by Amifostine

Taste buds in the oral cavity have a complex immune system regulating normal functions and inflammatory reactions. Cyclophosphamide (CYP), a chemotherapy drug, has wide-ranging disruptive effects on the taste system including loss of taste function, taste sensory cells, and capacity for taste cell renewal. In bladder epithelium, CYP also induces inflammation. To determine if CYP induces inflammation in taste buds, we used immunohistochemistry to examine tumor necrosis factor alpha (TNF-α) (a proinflammatory cytokine) expression over a 72-hour period. Expression of TNF-α increased in a subset of PLCβ2 labeled (Type II) cells, but not SNAP-25 labeled (Type III) cells, between 8 and 24 h postinjection and declined slowly thereafter. This inflammatory response may play an important role in the disruptive effects of CYP on the taste system. Further, pretreatment with amifostine, a sulfhydryl drug known to protect normal tissues during chemo- or radiation therapy, reduced the amount of CYP-induced TNF-α expression in taste buds, suggesting this drug is capable of protecting normal cells of the taste system from adverse effects of CYP. Amifostine, used as a pretreatment to CYP and possibly other chemotherapy drugs, may offer clinical support for preventing negative side effects of chemotherapy on the taste system.

Taste and Smell Function in Head and Neck Cancer Survivors

Survivors of head and neck squamous cell cancers (HNSCC) frequently complain of taste dysfunction long after radiation therapy is completed, which contradicts findings from most sensory evaluation studies that predict dysfunction should resolve few months after treatment. Therefore, it remains unclear whether taste and smell function fully recovers in HNSCC survivors. We evaluated HNSCC survivors (n = 40; age 63 ± 12 years, mean ± standard deviation) who received radiation therapy between 6 months and 10 years before recruitment and compared their responses to those of a healthy control group (n = 20) equivalent in age, sex, race, smoking history, and body mass index. We assessed regional (tongue tip) and whole-mouth taste intensity perception using the general Labeled Magnitude Scale and smell function using the University of Pennsylvania Smell Identification Test (UPSIT). To determine possible differences between groups in retronasal smell perception, we used solutions of sucrose with strawberry extract, citric acid with lemon extract, sodium chloride in vegetable broth, and caffeine in coffee and asked participants to rate perceived smell and taste intensities with and without nose clips. We found groups had similar UPSIT and taste intensity scores when solutions were experienced in the whole mouth. However, HNSCC survivors were less likely to identify low concentrations of bitter, sweet, or salty stimuli in the tongue tip relative to healthy controls. Our findings suggest persistent and subtle localized damage to the chorda tympani or to the taste buds in the fungiform papillae of HNSCC survivors, which could explain their sensory complaints long after completion of radiotherapy.

Transient Effects of Cyclophosphamide on Basal Cell Proliferation of Olfactory Epithelia

Cancer is often treated with broad-spectrum cytotoxic drugs that not only eradicate cancerous cells but also have detrimental side effects. One of these side effects, disruption of the olfactory system, impedes a patient's ability to smell, perceive flavor, and ultimately may interfere with their nutritional intake and recovery from cancer. Recent studies reported that the chemotherapy drug, cyclophosphamide (CYP), can damage gustatory epithelia and disrupt cell proliferation in olfactory epithelia. In this study, we asked if CYP altered globose and horizontal basal cell proliferation in the murine main olfactory epithelium (MOE) and vomeronasal organ (VNO). We used antibodies for Ki67, a marker strictly associated with cell proliferation, and Keratin 5, a marker for the cytoskeleton of horizontal basal cells. Our results revealed a significant CYP-induced decrease in the number of proliferative cells in both epithelia, especially globose basal cells in the MOE, within the first 1-2 days postinjection. Recovery of cell renewal was apparent 6 days after injection. The immunohistochemical markers showed significantly higher levels of globose and horizontal basal cell proliferation in CYP-injected mice at 14 and 30 days postinjection compared with control mice. The prolonged proliferative activation of globose and horizontal basal cells suggests that, besides altering proliferation of olfactory epithelia, the epithelial substrate needed for successful cell renewal may be adversely affected by CYP.

ALTERTASTE: improving food pleasure and intake of oncology patients receiving chemotherapy

ALTERTASTE is a prospective study to evaluate changes in taste/flavor perception and food preferences in patients treated with adjuvant or neoadjuvant chemotherapy for breast or colorectal cancer. The study adopts a longitudinal approach. Taste and odor responsiveness, food preferences and habits, emotions elicited by foods, and quality of life will be measured at six-time points: before chemotherapy (T0), after two cycles (T1, after around 1 month), after four cycles (T2, after around 2 months), after six cycles (T3, after around 4 months), at the end of chemotherapy (T4, after around 6 months) and 3 months after the conclusion of the therapy (T5). In addition, patients will be characterized for oral responsiveness and their psychological traits and attitudes toward food. The ALTERTASTE trial is expected to improve the understanding of the impact of chemotherapy on taste and smell and the repercussions of these alterations on food behaviors. Furthermore, the trial aims to develop an easy and reliable procedure to test smell, taste and food behavior alterations to allow a routine measure with patients. Clinical trial registration: NCT04495387 (ClinicalTrials.gov).

The effects of zinc on radiation-induced dysgeusia: a systematic review and meta-analysis

PURPOSE

Many head and neck cancer patients who receive radiation therapy experience radiation-induced dysgeusia (RID), which has no standard treatment. The only supplement controlled clinical trials have evaluated for the treatment of RID is zinc. However, the results of these and other studies investigating the use of zinc for RID have been inconsistent. To assess the validity of zinc as a treatment for RID, we conducted a systematic literature search and performed a meta-analysis to determine the extent to which zinc affects RID incidence and the degree to which ongoing RID responds to zinc.

METHODS

We searched the Ovid MEDLINE, Ovid Embase, PubMed, and Cochrane Library databases to identify studies investigating the use of zinc-based therapy for RID in head and neck cancer patients treated with radiation that were published between January 1, 2003, and November 9, 2017. Using American Society of Clinical Oncology criteria, we selected studies with a high level of evidence for inclusion in the meta-analysis.

RESULTS

Of the 32 full-text articles eligible for inclusion, three were included in the final review and meta-analysis. The meta-analysis showed that, compared with placebo, zinc reduces the incidence of RID (risk ratio, 0.72; 95% confidence interval, 0.67-0.92) but does not improve taste acuity more rapidly following radiation therapy (risk ratio, 2.58; 95% confidence interval, 0.97-6.88).

CONCLUSION

Our findings indicate that zinc-based therapy reduces the incidence of RID but has a minimal effect on ongoing RID. Our findings also highlight the need for additional evidence-based research on this topic.

Drinking Ice-Cold Water Reduces the Severity of Anticancer Drug-Induced Taste Dysfunction in Mice

Taste disorders are common adverse effects of cancer chemotherapy that can reduce quality of life and impair nutritional status. However, the molecular mechanisms underlying chemotherapy-induced taste disorders remain largely unknown. Furthermore, there are no effective preventive measures for chemotherapy-induced taste disorders. We investigated the effects of a combination of three anticancer drugs (TPF: docetaxel, cisplatin and 5-fluorouracil) on the structure and function of mouse taste tissues and examined whether the drinking of ice-cold water after TPF administration would attenuate these effects. TPF administration significantly increased the number of cells expressing apoptotic and proliferative markers. Furthermore, TPF administration significantly reduced the number of cells expressing taste cell markers and the magnitudes of the responses of taste nerves to tastants. The above results suggest that anticancer drug-induced taste dysfunction may be due to a reduction in the number of taste cells expressing taste-related molecules. The suppressive effects of TPF on taste cell marker expression and taste perception were reduced by the drinking of ice-cold water. We speculate that oral cryotherapy with an ice cube might be useful for prophylaxis against anticancer drug-induced taste disorders in humans.

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.

Patient-reported taste change assessment questionnaires used in the oncology setting: A narrative review

PURPOSE

Patient-reported questionnaires to assess taste changes (TC) among patients with cancer and the common domains or aspects assessed by those questionnaires are identified in this narrative review. Taste changes are a prevalent symptom experienced by patients with cancer that impact food choice and enjoyment, reduce food intake, and diminish quality of life. Appropriate assessment is essential to detect and manage this symptom.

METHOD

A systematic search of relevant databases between 1999 and 2018 yielded 1959 articles; 38 articles were included in the review.

RESULTS

Seventeen questionnaires designed specifically to assess patient-reported taste changes among patients with cancer are described in the review. Seven domains were identified among the questionnaires; the most frequently assessed domain was the description of the taste change in 14 questionnaires). Timeframe, scoring, number of items and domains, and item phrasing varied greatly among questionnaires and the approach to domain and item evaluation was inconsistent. Comprehensive questionnaires (n = 7) assessed five or more domains to characterize the taste change experience. The majority of questionnaires have been cited only once or twice.

CONCLUSION

Patient-reported taste change assessment in oncology has been achieved by a large number of diverse questionnaires; no standard tool or approach is used. Development of a question bank of validated or standardized taste change modules or items may strengthen the consistency and applicability of research in this area.

Taste alterations in patients with breast cancer following chemotherapy: a cohort study

BACKGROUND

Chemotherapy-induced taste and smell alterations in cancer patients are associated with multiple adverse effects, namely, malnutrition, weight loss, and a diminished quality of life. The aim of this prospective study was to identify the incidence of taste alterations following epirubicin and cyclophosphamide (EC) chemotherapy in patients with breast cancer without previous history of cancer or chemotherapy.

METHODS

Forty-one patients undergoing EC chemotherapy for breast cancer at Tokai University Hospital were included. A subjective (questionnaire) and an objective (filter paper disk method) assessment for 5 basic tastes were administered on day 4 post-chemotherapy and immediately before the subsequent cycle of chemotherapy for each cycle, in addition to an olfactory evaluation and oral examination. The correlation between subjective and objective taste alterations and factors influencing these alterations were analyzed by statistical means.

RESULTS

The mean incidence of subjective taste alteration on the 4th day after chemotherapy was 53%. In each of the 4 cycles, taste alterations decreased to about 9.0% immediately before the next cycle. A significant correlation between subjective and objective assessments was seen only for salty taste, suggesting important differences in subjective versus objective assessment outcomes. A multivariate analysis indicated that age and body surface area influenced taste alterations.

CONCLUSIONS

EC chemotherapy induced taste alterations in more than 50% of patients, which decreased to less than 10% immediately before the next chemotherapy cycle. A combination of objective and subjective assessments is essential to evaluate taste alterations induced by EC chemotherapy. These could be used in routine clinical practice.

The impact of hematological malignancies and their treatment on oral health-related quality of life as assessed by the OHIP-14: a systematic review

Patients with hematologic cancers often develop acute and chronic oral complications from their disease and its treatment. These problems could change patients' oral health-related quality of life (OHRQoL) negatively. Quality of life (QoL) has become an increasingly important outcome measure in oncology. This systematic literature review evaluates the impact of hematological malignancies and their treatment on OHRQoL as assessed by the Oral Health Impact Profile (OHIP-14) questionnaire. Medline through Pubmed and Web of Science were searched through April 2017. Two randomized controlled trials, one cohort study, one cross-sectional study, and one case-control study were included. Heterogeneity across the included studies did not allow for meta-analysis. OHIP-14 domains that were frequently given the highest scores were functional limitation (67%), physical pain (50%), physical disability (50%), and psychological discomfort (33%). The domains that were frequently given the lowest scores were social handicap (100%), social disability (100%), and psychological disability (67%). Insufficient evidence is available to draw any robust conclusions regarding OHRQoL assessed by the OHIP-14 in individuals with hematological malignancies. However, functional limitations because of problems with oral mucosal tissues, the dentition, or dentures, seem to have a larger negative impact on the OHRQoL than social aspects associated with oral health problems. Well-designed larger studies are required to determine effects of hematological malignancies as well as acute and long-term effects of their treatment on patients' OHRQoL.

Chemosensory Changes from Cancer Treatment and Their Effects on Patients' Food Behavior: A Scoping Review

Individuals undergoing treatment for cancer can experience changes in taste or smell that are often assumed to affect constructs related to food behavior, although this relationship is rarely measured directly. To ascertain the extent to which measured changes in taste and smell during and after cancer treatment affect food behavior, we conducted a scoping review and completed a comparative analysis for studies that met our criteria, which were: they directly measured cancer patients’ (a) psychophysical response to taste and/or olfactory stimuli, and (b) food behavior (including food enjoyment, food preference, dietary intake) in people affected by cancer. Eleven studies met these criteria and were included in the review. All 11 studies evaluated taste and five also measured smell. A comparative analysis exploring taste and food behavior shows that a reduced sweet taste function (decreased sensitivity) was associated with a reduced intake of a variety of different macro and micro nutrients, reduced appetite, and overall lower energy intake. One out of six studies that measured smell and food measured observed changes in olfactory function following cancer treatment. There were no significant relationships reported between olfactory measures and food behavior. Taste changes that arise from cancer treatment appear to have a direct effect on food behavior, although there is a need for more research using standardized measures and larger sample sizes. A better understanding of taste alterations and their implications for dietary intake and food enjoyment will support optimal nutritional health by identifying strategies to help patients eat well during and after cancer treatment.

Effect of using tobacco on taste perception

Background:

Impaired taste perception has impact on quality of life. Tobacco is a perilous factor that contributes to an impaired taste.

Objective:

To evaluate and compare taste perception among tobacco chewers and nonchewers.

Materials and Methods:

Sixty subjects (30 tobacco chewers + 30 nonchewers as controls) were enrolled in the study for evaluating taste perception. Taste identification time using four aqueous solutions of basic tastes – sweet, salty, sour, and bitter – was recorded (in seconds) and compared between tobacco chewers and controls. The data were analyzed using Student's t-test and analysis of variance using SPSS 20 version software.

Results:

A statistically significant increase in taste identification time for salty taste in tobacco chewers (12.32 s) was noted compared with nonchewers (10.21 s) (P = 0.03). The average taste identification time was higher for tobacco chewers than nonchewers for sweet and salty taste. However, the average taste identification time was lower for tobacco chewers than nonchewers for sour and bitter taste. In nonchewers, the average taste identification time was 13.01, 10.21, 8.43, and 7.56 s for sweet, salty, bitter, and sour taste, respectively. In tobacco chewers, the average taste identification time was 15.16, 12.32, 7.75, and 7.04 s for sweet, salty, bitter, and sour taste, respectively.

Conclusion:

The results of the study demonstrated noticeable decrease in taste perception to salty taste among tobacco chewers when compared with tobacco nonchewers. There is a remarkable difference in taste perception to basic tastes among tobacco chewers and controls.

Association of oral toxicity and taste changes during hematopoietic stem cell transplantation: a preliminary study

PURPOSE

The aim of this study was to characterize the taste changes and taste bud atrophy observed in the period of neutropenia of HCT and to determine the influence of transplantation toxicity on these changes.

METHODS

Autologous and allogeneic HCT patients (n = 51) were selected to perform taste acuity tests prior to conditioning (T0) and during neutropenia (T1). The frequency and time duration of oral mucositis, presence of tongue depapillation, and salivary flow rate were also evaluated. Quality of life was assessed using specific questionnaires.

RESULTS

We observed a significant increase in hypogeusia (66.6%, p = 0.001) and dysgeusia (21.4%, p = 0.013) at T1, compared with T0. Bitter taste was the most altered, mainly when the patient underwent conditioning with melphalan (OR = 4.47, p = 0.049). Prolonged oral mucositis (≥ 8 days) (OR = 5.62, p = 0.039) and autologous transplantation (OR = 4.08, p = 0.033) were predictive factors for tongue depapillation. Changes in sour taste (OR = 10.70, p = 0.045) and reduced salivary flow (OR = 21.00, p = 0.013) were associated to body weight loss at T1. Taste changes significantly reduced the quality of life at T1, compared with T0.

CONCLUSIONS

Frequency of hypogeusia was high in the neutropenia period of the HCT. None of the taste changes was determined by oral mucositis, tongue depapillation, or reduced salivary flow, but melphalan conditioning reduced the bitter taste sensation. Loss of body weight and poor quality of life were associated with taste changes and reduced salivary flow. Further studies are necessary to elucidate this association and the risk factors for taste changes in HCT.

Modifications of taste sensitivity in cancer patients: a method for the evaluations of dysgeusia

PURPOSE

Taste changes due to chemotherapy may contribute to the high prevalence of malnutrition in cancer patients. It is believed that 50-70% of patients with cancer suffer from taste disorders. The aim of the present study was to analyze the taste alterations in patient population compared with that in controls, also in relation to gender. In this way, it could open to a new approach for a personalized diet to prevent and/or reduce taste alterations and malnutrition in cancer patients.

METHODS

Forty-five cancer patients undergoing chemotherapy were compared with healthy controls (n = 32). Taste function test was used to determine taste sensitivity. Different concentrations for each of the four basic tastes (salty, sweet, sour, bitter) and also fat and water tastes were evaluated.

RESULTS

A significant difference in taste sensitivity between patients and control group was found, in line with previous similar studies. As in the control group, taste perception in patients was better in females than in males, suggesting interaction effect between group and gender.

CONCLUSIONS

Coping strategies regarding subjective taste impairment should be provided since alterations in taste sensitivity influence food preferences and appetite. Clinicians could thus have the potential to underpin changes in dietary intake and consequently in nutritional status; understanding the extent of the contribution of each taste would help in the development of effective interventions in future. Consequently, patients can adopt appropriate appetizing strategies and, based on that, change their feeding habits.

Metal Ions Activate the Human Taste Receptor TAS2R7

Divalent and trivalent salts exhibit a complex taste profile. They are perceived as being astringent/drying, sour, bitter, and metallic. We hypothesized that human bitter-taste receptors may mediate some taste attributes of these salts. Using a cell-based functional assay, we found that TAS2R7 responds to a broad range of divalent and trivalent salts, including zinc, calcium, magnesium, copper, manganese, and aluminum, but not to potassium, suggesting TAS2R7 may act as a metal cation receptor mediating bitterness of divalent and trivalent salts. Molecular modeling and mutagenesis analysis identified 2 residues, H943.37 and E2647.32, in TAS2R7 that appear to be responsible for the interaction of TAS2R7 with metallic ions. Taste receptors are found in both oral and extraoral tissues. The responsiveness of TAS2R7 to various mineral salts suggests it may act as a broad sensor, similar to the calcium-sensing receptor, for biologically relevant metal cations in both oral and extraoral tissues.

Nutritional Status of Patients with Cancer: A Prospective Cohort Study of 1,588 Hospitalized Patients

BACKGROUND

We aimed to assess the nutritional status of cancer patients according to site or treatment type.

METHODS

We prospectively evaluated the nutritional status of 1,588 patients based on cancer site and treatment type using the Patient-Generated Subjective Global Assessment tool. We also investigated length of stay (LOS), complication rates after surgery and quality of life (QoL).

RESULTS

The patients with esophageal, pancreaticobiliary, and lung cancer had higher malnutrition rates than those with stomach, liver, and colon cancer (52.9%, 47.6%, and 42.8% vs. 29.1%, 24.7%, and 15.9%, respectively; P < 0.05). Patients undergoing chemoradiotherapy (CRT) or supportive care had higher malnutrition rates than those undergoing surgery (35.2% or 68.6% vs. 12.3%; P < 0.05). Among patients undergoing surgery, malnourished patients had longer LOS and tended to have more complications than well-nourished patients (P < 0.05 and P = 0.146, respectively). Malnourished patients had also poorer QoL than well-nourished patients (P < 0.05).

CONCLUSION

Malnutrition complicated more in patients with esophageal, pancreaticobiliary, or lung cancer than in those with stomach, liver, or colon cancer. Patients undergoing CRT or supportive care are more likely to be malnourished than those undergoing surgery. Malnutrition may increase LOS and impair QoL.

Augmented Flavours: Modulation of Flavour Experiences Through Electric Taste Augmentation

In recent years there has been a growing interest in the potential benefits and new applications that may be afforded by incorporating digital flavour augmentation technologies into traditional eating and drinking experiences. Although many studies have shown how controlled olfactory, visual and auditory cues can impact flavour experiences, there has been a relatively small amount of work that has investigated the utilisation of digital gustatory (taste) augmentation in the same context. Hence, we have created two utensils, a pair of chopsticks and a soup bowl, that apply controlled electrical pulses to the tip of the tongue during consumption in order to augment flavours through electrical stimulation. As such, in this paper we present a study that aimed to evaluate the impact of electric taste augmentation on two types of eating experiences: consuming mashed potato and miso soup. Based on this study, our findings demonstrate that 1) significant increases in perceived saltiness and sourness can be achieved when consuming unsalted mashed potato and 2) significantly higher ratings of sourness can be achieved when consuming diluted miso soup.

Development and validation of the taste alteration scale for children receiving chemotherapy

BACKGROUND

Taste alteration is one of the most common and frequently ignored side effects of chemotherapy.

AIMS

Our aim was to develop the Taste Alteration Scale for Children with Cancer Receiving Chemotherapy (TAS-CrC).

METHODS

This study is a descriptive and cross-sectional type. The study was conducted between May and September 2016 at the child haematology clinics and outpatient clinics of six hospitals. A total of 165 children with cancer who were followed in the clinics and outpatient clinics of the mentioned hospitals between May and September 2016 and received chemotherapy constituted the population of the study. Our sample comprised 95 children with cancer who were followed in the clinic and outpatient clinic between the dates specified and met the study criteria.

RESULTS

It is observed that the correlation values of the item analysis of the TAS-CrC vary between 0.49 and 0.86. One sub-dimension of the scale was determined by explanatory factor analysis. The Cronbach's alpha reliability coefficient of the scale was determined to be 0.88. It was determined that there was a statistically significant relationship between the test-retest (first and second application) of the scale (p < 0.01).

CONCLUSIONS

According to the data obtained from the study, it was determined that the TAS-CrC was a valid and reliable scale.

Taste changes as a metaphor for biographical disruption: A qualitative study in patients undergoing haematopoietic stem cell transplantation

PURPOSE

and objective: The treatment side effects of patients undergoing haematopoietic stem cell transplantation can cause various eating difficulties. The objective of this study was to explore the significance of eating experiences and taste changes from the perspective of patients undergoing haematopoietic stem cell transplantation.

METHOD

This was a qualitative, exploratory study based on semi-structured interviews applied during hospitalisation for haematopoietic stem cell transplantation. Thematic content analysis and the biographical disruption concept were used as theoretical references to explore the results.

RESULTS

Twenty patients were studied. The overarching theme identified from the results was deconstruction of the taste reference resulting from sensory taste change, loss of eating references and changes to the hedonic relationship with food caused by the treatment. In addition to this deconstruction, participants described the reformulation of eating habits as a way of coping with the disease, which affected the eating experience and motivated the dietary strategies adopted.

CONCLUSIONS

Taste changes during haematopoietic stem cell transplantation are related to both biological issues and metaphysical aspects. This study raises the meaning of loss of sensory references and their symbolic aspects. These results were important to expand our view to include other aspects that can contribute to improving the care given to these individuals.

The habenula as a novel link between the homeostatic and hedonic pathways in cancer-associated weight loss: a pilot study

BACKGROUND

Little is known about the brain mechanisms underlying cancer-associated weight loss (C-WL) in humans despite this condition negatively affecting their quality of life and survival. We tested the hypothesis that patients with C-WL have abnormal connectivity in homeostatic and hedonic brain pathways together with altered brain activity during food reward.

METHODS

In 12 patients with cancer and 12 healthy controls, resting-state functional connectivity (RSFC, resting brain activity observed through changes in blood flow in the brain which creates a blood oxygen level-dependent signal that can be measured using functional magnetic resonance imaging) was used to compare three brain regions hypothesized to play a role in C-WL: the hypothalamus (homeostatic), the nucleus accumbens (hedonic), and the habenula (an important regulator of reward). In addition, the brain reward response to juice was studied. Participants included 12 patients with histological diagnosis of incurable cancer (solid tumours), a European Cooperative Oncology Group performance status of 0-2, and a ≥5% involuntary body weight loss from pre-illness over the previous 6 months and 12 non-cancer controls matched for age, sex, and race. RSFC between the hypothalamus, nucleus accumbens, and habenula and brain striatum activity as measured by functional MRI during juice reward delivery events were the main outcome measures.

RESULTS

After adjusting for BMI and compared with matched controls, patients with C-WL were found to have reduced RSFC between the habenula and hypothalamus (P = 0.04) and between the habenula and nucleus accumbens (P = 0.014). Patients with C-WL also had reduced juice reward responses in the striatum compared with controls.

CONCLUSIONS

In patients with C-WL, reduced connectivity between both homeostatic and hedonic brain regions and the habenula and reduced juice reward were observed. Further research is needed to establish the relevance of the habenula and striatum in C-WL.

Assessing taste and smell alterations in cancer patients undergoing chemotherapy according to treatment

PURPOSE

Taste and smell changes are common side effects in cancer patients undergoing chemotherapy treatments (CT). This can lead to a reduced food enjoyment and an inadequate nutrient intake with a high impact on nutritional status and quality of life. The aim of this study was to evaluate the self-reported chemosensory alterations of patients undergoing chemotherapy according to CT type.

METHODS

An observational study was conducted with 151 patients undergoing CT at Oncology Outpatient Unit from Onkologikoa Foundation. An interviewer-assisted questionnaire was designed to investigate chemosensory changes in patients undergoing CT.

RESULTS

Seventy-six percent patients reported taste disorders and 45% smell changes. Xerostomia is the most frequent symptom reported by patients receiving chemotherapy in our study (63.6%), and it is strongly associated to bad taste in mouth (OR = 5.96; CI = 2.37-14.94; p value = 0.000) and taste loss (OR = 5.96; CI = 2.37-14.94; p value = 0.000). Anthracyclines, paclitaxel, carboplatin, and docetaxel were the CT agents producing the highest taste disturbance rates. Cisplatin and 5-Fluorouracil are the CT resulting in the lowest complaints. Logistic regression revealed statistically significant associations between taste loss and carboplatin and docetaxel (OR = 3.50; CI = 1.12-10.90; p value = 0.031) and cold hypersensitivity and oxaliplatin (OR = 12.14; CI = 4.18-35.25; p value = 0.000). Not only platin-based CT such as carboplatin produced dysgeusia, but also anthracyclines and paclitaxel treatments.

CONCLUSIONS

The better knowledge of taste and smell alterations according to CT type may provide valuable information for the design of new strategies to tackle CT side effects. It is important to take into account taste and smell dysfunctions and other alterations such as xerostomia together.

Innovative food products for cancer patients: future directions

One of the main challenges for cancer patients under treatment is to prevent and tackle malnutrition. The current clinical nutrition market offers different food supplements or oral nutritional support products (mainly milkshakes or modified texture products) for cancer patients under risk of malnutrition. However, it is worth mentioning that these products do not address the pleasure of eating, since they do not meet sensory requirements, such as taste and smell alterations, nor patients' food preferences, leading to a big impact on their quality of life (QOL). Still, controversy remains regarding the specific nutritional requirements for cancer patients during the disease. Several randomized controlled clinical trials yield opposite results when using different bioactive compounds such as omega-3 fatty acids or antioxidants in order to prevent malnutrition or improve QOL. The use of 'omics' technologies in oncology, such as membrane lipidomics, as a powerful tool to provide new insights for the understanding of diet and cancer and their interacting metabolic pathways, will be discussed. The better knowledge of specific requirements (nutrients, sensory parameters and food preferences) for cancer patients provides valuable information for the food industry in the design of customized food products capable of preventing malnutrition, alleviating symptoms and improving QOL. © 2017 Society of Chemical Industry.

Dealing with taste and smell alterations-A qualitative interview study of people treated for lung cancer

Taste and smell alterations have been recognized as common symptoms in relation to various cancers. However, previous research suggests that patients do not receive sufficient support in managing taste and smell alterations. Therefore, the objective of this study is to investigate how persons with experience from lung cancer-related taste and smell alterations reason about resources and strategies offered and used to manage these symptoms. Data from semi-structured individual interviews with 13 women and four men were analyzed with qualitative content analysis. We used Kleinman’s now classic medical anthropological model of local health care systems, consisting of the personal, professional, and folk sector, to interpret and understand how people respond to sickness experiences in their daily lives. By presenting the findings using this model, we demonstrate that most strategies for dealing with taste and smell alterations were undertaken in the personal sector, i.e. in participants’ daily lives, on an individual level and in interaction with family, social networks and communities. Taste and smell alterations implied two overarching challenges: 1) adjusting to no longer being able to trust information provided by one’s own senses of taste and/or smell, and 2) coming to terms with taste and smell alterations as a part of having lung cancer. Health care professionals’ involvement was described as limited, but appeared to fulfil most participants’ expectations. However, through provision of normalizing information, practical advice, and to some extent, emotional support, health care professionals had potential to influence strategies and resources used for dealing with taste and smell alterations. With this study, we further the understanding of how people deal with lung cancer-related taste and smell alterations and discuss the role of health care professionals for this process.

Unlocking the Complex Flavors of Dysgeusia after Hematopoietic Cell Transplantation

Dysgeusia is a frequently occurring symptom after hematopoietic cell transplantation (HCT) that has important long-term effects on physical, nutritional, and immunologic recovery, as well as on quality of life. Despite the relevance of this symptom, the study of dysgeusia in patients undergoing HCT has been limited, owing in part to its complexity. In this article, we review normal taste function and its clinical evaluation, discuss how dysgeusia uniquely affects patients undergoing HCT, and examine distinct, transplantation-related contributors to dysgeusia that may help elucidate strategies to ultimately reduce this symptom burden after transplantation.

Cellular mechanisms of cyclophosphamide-induced taste loss in mice

Many commonly prescribed chemotherapy drugs such as cyclophosphamide (CYP) have adverse side effects including disruptions in taste which can result in loss of appetite, malnutrition, poorer recovery and reduced quality of life. Previous studies in mice found evidence that CYP has a two-phase disturbance in taste behavior: a disturbance immediately following drug administration and a second which emerges several days later. In this study, we examined the processes by which CYP disturbs the taste system by examining the effects of the drug on taste buds and cells responsible for taste cell renewal using immunohistochemical assays. Data reported here suggest CYP has direct cytotoxic effects on lingual epithelium immediately following administration, causing an early loss of taste sensory cells. Types II and III cells in fungiform taste buds appear to be more susceptible to this effect than circumvallate cells. In addition, CYP disrupts the population of rapidly dividing cells in the basal layer of taste epithelium responsible for taste cell renewal, manifesting a disturbance days later. The loss of these cells temporarily retards the system’s capacity to replace Type II and Type III taste sensory cells that survived the cytotoxic effects of CYP and died at the end of their natural lifespan. The timing of an immediate, direct loss of taste cells and a delayed, indirect loss without replacement of taste sensory cells are broadly congruent with previously published behavioral data reporting two periods of elevated detection thresholds for umami and sucrose stimuli. These findings suggest that chemotherapeutic disturbances in the peripheral mechanisms of the taste system may cause dietary challenges at a time when the cancer patient has significant need for well balanced, high energy nutritional intake.

Alteration in Taste Perception in Cancer: Causes and Strategies of Treatment

The sense of taste is responsible for the detection and ingestion of food to cover energetic requirements in health and disease. The change in taste perception might lead to malnutrition that is usually one of the frequent causes of morbidity and mortality in patients with cancer. In this review, we summarize the mechanisms of taste perception and how they are altered in cancer. We also address the question of the implication of inflammation, responsible for the alterations in taste modalities. We highlight the role of radio- and chemotherapy in the modulation of taste physiology. Other several factors like damage to taste progenitor cells and disruption of gut microbiota are also dealt with relation to taste perception in cancer. We further shed light on how to restore taste acuity, by using different preventive methods, dietary modifications and pharmacotherapy in subjects with advanced cancer state.

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

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.

Oxaliplatin Alters Expression of T1R2 Receptor and Sensitivity to Sweet Taste in Rats

As one of the adverse effects of oxaliplatin, a key agent in colon cancer chemotherapy, a taste disorder is a severe issue in a clinical situation because it decreases the quality of life of patients. However, there is little information on the mechanism underlying the oxaliplatin-induced taste disorder. Here, we examined the molecular and behavioral characteristics of the oxaliplatin-induced taste disorder in rats. Oxaliplatin (4-16 mg/kg) was administered to Sprague-Dawley (SD) rats intraperitoneally for 2 d. Expression levels of mRNA and protein of taste receptors in circumvallate papillae (CP) were measured by real-time quantitative polymerase chain reaction (PCR) and immunohistochemistry, respectively. Taste sensitivity was assessed by their behavioral change using a brief-access test. Morphological change of the taste buds in CP was evaluated by hematoxyline-eosin (HE) staining, and the number of taste cells in taste buds was counted by immunohistochemical analysis. Among taste receptors, the expression levels of mRNA and protein of T1R2, a sweet taste receptor subunit, were increased transiently in CP of oxaliplatin-administered rats on day 7. In a brief-access test, the lick ratio was decreased in oxaliplatin-administered rats on day 7 and the alteration was recovered to the control level on day 14. There was no detectable alteration in the morphology of taste buds, number of taste cells or plasma zinc level in oxaliplatin-administered rats. These results suggest that decreased sensitivity to sweet taste in oxaliplatin-administered rats is due, at least in part, to increased expression of T1R2, while these alterations are reversible.