Olfaction in chemotherapy for head and neck malignancies

Smell and Taste Alterations in Patients Receiving Curative or Palliative Chemotherapy-The CONKO 021-ChemTox Trial

Previous data regarding chemotherapy-induced olfactory and gustatory dysfunction (CIOGD) are heterogeneous due to inconsistent study designs and small numbers of patients. To provide consistent, reliable data, we conducted a cohort study using standardized testing. Patients diagnosed with lymphoma, leukemia, or gastrointestinal malignancies were examined up to five times (T1 to T5), beginning prior to chemotherapy. We examined patients receiving temporary treatment up to 12 months post-therapy. Clinical assessment included extensive questionnaires, psychophysical tests of olfactory and gustatory function, and measurement of peripheral neuropathy. Statistical analysis included non-parametric tests to evaluate the longitudinal development of CIOGD. Our data (n = 108) showed a significant decline in olfactory and gustatory testing during chemotherapy (p-values < 0.001). CIOGD appeared stronger among patients above 60 years, while sex did not matter significantly. However, we identified distinct associations between CIOGD and reported anorexia as well as with higher neuropathy scores. Self-assessment appeared less sensitive to chemosensory dysfunction than psychophysical testing. Post-therapy, olfactory and gustatory function regenerated, though baseline levels were not attained within 6 to 12 months. In conclusion, our data highlight the wide prevalence and slow recovery of CIOGD. Understanding CIOGD as a potential neurotoxic effect may disclose new therapeutic prospects.

Taste and Smell Disorders in Cancer Treatment: Results from an Integrative Rapid Systematic Review

Taste and smell disorders (TSDs) are common side effects in patients undergoing cancer treatments. Knowing which treatments specifically cause them is crucial to improve patients' quality of life. This review looked at the oncological treatments that cause taste and smell alterations and their time of onset. We performed an integrative rapid review. The PubMed, PROSPERO, and Web of Science databases were searched in November 2022. The article screening and study selection were conducted independently by two reviewers. Data were analyzed narratively. Fourteen studies met the inclusion criteria and were included. A high heterogeneity was detected. Taste disorders ranged between 17 and 86%, while dysosmia ranged between 8 and 45%. Docetaxel, paclitaxel, nab-paclitaxel, capecitabine, cyclophosphamide, epirubicin, anthracyclines, and oral 5-FU analogues were found to be the drugs most frequently associated with TSDs. This review identifies the cancer treatments that mainly lead to taste and smell changes and provides evidence for wider studies, including those focusing on prevention. Further studies are warranted to make conclusive indication possible.

Dysphagia in Solid Tumors Outside the Head, Neck or Upper GI Tract: Clinical Characteristics

CONTEXT

Dysphagia is common in cancer, but underlying pathophysiology and manifestations within patients are unknown.

OBJECTIVES

To examine dysphagia characteristics in those with solid malignancies outside the head, neck and upper gastrointestinal tract.

METHODS

Seventy-three individuals with dysphagia (46 male, 27 female, aged 37-91) were recruited from a parent trial conducted in two acute hospitals and one hospice. Cranial nerve function, Oral Health Assessment Tool (OHAT), Mann Assessment of Swallowing Ability (MASA) and Functional Oral Intake Scale (FOIS) evaluated swallow profile.

RESULTS

Only 9/73 (12%) had documented dysphagia prior to study enrollment. MASA risk ratings found n=61/73 (84%) with dysphagia risk and n=22/73 (30%) with aspiration risk. Food texture modification was required for n=34/73 (47%), fluid texture modification for n=1/73 (1%). Compensatory strategies for food were needed by n=13/73 (18%) and for fluids by n=24/73 (33%). Cranial nerve deficits were present in n=43/73 (59%). Oral health problems were common, with xerostomia in two-thirds. Worse dysphagia on MASA was associated with disease progression, affecting hospice, and palliative care the most. Worse performance status was indicative of poorer MASA raw score (P<0.001, OR 2.2, 95% CI 1.5-3.4), greater risk of aspiration (P=0.005, OR 2.1, 95% CI 1.3-3.6) and lower FOIS (P=0.004, OR 2.0, 95% CI 1.2-3.2).

CONCLUSION

Dysphagia management in those with cancer requires robust assessment to uncover clinically important needs like food texture modification and safe swallowing advice. Better assessment tools should be developed for this purpose. Oral health problems should be routinely screened in this population since they exacerbate dysphagia.

Sinonasal Side Effects of Chemotherapy and/or Radiation Therapy for Head and Neck Cancer: A Literature Review

Radiotherapy and chemotherapy represent important treatment modalities for head and neck cancer. Rhinosinusitis and smell alterations are common side effects in the sinonasal region. This review will summarize and analyze our current knowledge of the sinonasal side effects of chemotherapy and/or radiation therapy for head and neck cancer (HNC), with a specific focus on mucosal and olfactory disorders. A review of the English literature was performed using several databases (PubMed, Embase, Cochrane, Scopus). Fifty-six articles were included in qualitative synthesis: 28 assessed mucosal disorders (rhinitis or rhinosinusitis), 26 evaluated olfactory alterations, and 2 articles addressed both topics. The incidence and severity of olfactory dysfunction and chronic rhinosinusitis were highest at the end of radiotherapy and at three months after treatment and decreased gradually over time. Smell acuity deterioration and chronic rhinosinusitis seemed to be related to radiation dose on olfactory area and nasal cavities, but different degrees of recovery were observed. In conclusion, it is important to establish the severity of chronic rhinosinusitis and olfactory dysfunction in order to find strategies to support patients and improve their quality of life.

The effect of chemotherapy on olfactory function and mucociliary clearance

OBJECTIVES

Olfactory sensory neurons and the olfactory mucosa are both important for optimal olfactory function. The potential nasal mucosal toxicity of chemotherapy regimens has not been assessed yet. The aim of this study was to objectively investigate the effect of chemotherapy on mucociliary clearance and olfactory function and to evaluate whether this effect differs between different chemotherapy regimens and age groups.

PATIENTS AND METHODS

The study included consecutive patients admitted for the treatment of a variety of primary tumors (except head and neck and brain malignancies). Patients were evaluated for olfaction and mucociliary clearance before and immediately after completing the last session of chemotherapy cycles, according to the therapeutic protocol. For objective evaluation, the saccharine test was used for mucociliary clearance and the Sniffin' Sticks test for olfactory function. Of the 46 initial patients, 30 completed the study. Groups were formed according to the chemotherapy regimen (four groups: CA (doxorubicin + cyclophosphamide), Folfox (oxaliplatin +5-FU + folinic acid), DCF (docetaxel + cisplatin +5-FU), and GC (gemcitabine + cisplatin)) and according to age (two groups: < 55 years and > 55 years).

RESULTS

In the overall analyses, significant deterioration was noted in both mucociliary clearance time and smell scores (olfactory threshold (OT), olfactory discrimination (OD), olfactory identification (OI), and the composite threshold-discrimination-identification (TDI) score). The changes in these scores showed no significant differences between chemotherapy groups. The decrease in OT and global TDI scores was more severe in the younger age group.

CONCLUSIONS

Chemotherapy impairs both the mucociliary clearance and olfactory function in cancer patients. This might reflect the collective negative effect of chemotherapy on olfactory function, not only through the neurocytotoxic effect but also the cytotoxic effect on the nasal mucosa. In addition, the reduction in olfactory threshold and total olfactory function scores was seen to be more profound in younger patients, which could have been due to higher initial scores.

Testicular cancer patients undergoing cisplatin based chemotherapy exhibit temporary olfactory threshold scores changes

Testicular cancer is the most frequent malignant disease in young males between 15 and 35 years. Platinum based chemotherapy regimen is the therapy of choice in advanced disease. This treatment has also adverse effects caused by the cytostatic active substances, such as olfactory dysfunctions. The aim of this study was, therefore, to monitor olfactory function of testicular cancer patients during and 6 months after chemotherapy. A total of 17 patients (mean age 31.06 ± 10.26 years), which underwent chemotherapy (mean 2.47 cycles ± 0.5) were enrolled in this study. Odor threshold, discrimination and identification were assessed by means of the "Sniffin' Sticks" prior to and on day 42, 90 and 180 after chemotherapy has been completed. Furthermore, patients' ratings of olfactory function and depressive symptoms were evaluated. Threshold scores were significantly lower on day 90 (8.0 ± 2.51) compared to baseline (10.4 ± 2.20) (p = 0.014) and recovered almost completely on day 180 (9.65 ± 3.26). Odor discrimination and identification did not show significant changes during therapy. The decrease of the olfactory function during/immediately after chemotherapy was underlined by the subjectively perceived impaired olfactory function during this time. In addition almost every fourth patient presented with a depressed mood at the beginning of chemotherapy. Patients should be informed about possible transient olfactory impairment during/immediately after chemotherapy.