Association between variants of 5-hydroxytryptamine receptor 3C (HTR3C) and chemotherapy-induced symptoms in women receiving adjuvant treatment for breast cancer.

Administration of chemotherapy is associated with a wide array of symptoms affecting quality of life. Genetic risk factors for severity of chemotherapy-induced symptoms have not been determined. The present study aimed to explore the associations between polymorphisms in candidate genes and chemotherapy-induced symptoms. Women treated with at least two cycles of adjuvant doxorubicin and cyclophosphamide, with or without paclitaxel for early breast cancer (n = 105) completed the memorial symptom assessment scale and provided blood for genotyping. DNA was extracted from peripheral blood leukocytes and assayed for single nucleotide polymorphisms (SNPs) in GTP cyclohydrolase 1 (GCH1, rs10483639, rs3783641, and rs8007267), catecholamine-o-methyltransferase (COMT, rs4818), and 5-hydroxytryptamine (serotonin) receptor 3C (HTR3C, rs6766410, and rs6807362). Genotyping of HTR3C revealed a significant association between the presence of rs6766410 and rs6807362 SNPs (K163 and G405 variants) and increased severity of symptoms (p = 0.0001 and p = 0.007, respectively). Multiple regressions revealed that rs6766410 and rs6807362, but not age or stage at diagnosis, predicted severity of symptoms (p = 0.001 and p = 0.006, respectively) and explained 12 % of the variance in each regression model. No association was found between the genetic variants of CGH1 or COMT and symptom score. Our study indicates, for the first time, an association between variants of HTR3C and severity of chemotherapy-induced symptoms. Analyzing these genetic variants may identify patients at increased risk for the development of chemotherapy-induced symptoms and targeting the serotonin pathway may serve as a novel treatment strategy for these patients.

The symptom experience of oncology outpatients has a different impact on quality-of-life outcomes.

The aims of this replication study were to determine if subgroups of oncology outpatients receiving active treatment could be identified based on their experience with the symptoms of fatigue, sleep disturbance, depression, and pain; whether patients in these subgroups differed on selected demographic, disease, and treatment characteristics; and if patients in these subgroups differed on functional status and quality of life (QOL). A convenience sample of 228 oncology outpatients was recruited from seven outpatient settings in Israel. Patients completed a demographic questionnaire, a Karnofsky Performance Status score, the Multidimensional Quality of Life Scale-Cancer, the Lee Fatigue Scale, the General Sleep Disturbance Scale, the Center for Epidemiological Studies-Depression Scale, and a numeric rating scale of worst pain intensity. Cluster analysis was used to identify the patient subgroups based on their symptom experience. Four relatively distinct patient subgroups were identified based on their experiences with the above symptoms (i.e., low levels of all four symptoms (32.9%), low levels of pain and high levels of fatigue (18.0%), high levels of pain and moderate levels of fatigue (42.5%), and high levels of all four symptoms (6.6%). No differences were found among the four subgroups on any demographic, disease, or treatment characteristics. The subgroup of patients who reported high levels of all four symptoms reported the worst functional status and poorest QOL. In conclusion, differences in the symptom experience of oncology outpatients suggest that patients may harbor different phenotypic characteristics (e.g., environmental or physiologic) or genetic determinants for experiencing symptoms that are independent of demographic, disease, and treatment characteristics.

The Effect of Reflexology on the Pain-Insomnia-Fatigue Disturbance Cluster of Breast Cancer Patients During Adjuvant Radiation Therapy.

OBJECTIVE: To evaluate the effects of reflexology treatment on quality of life, sleep disturbances, and fatigue in breast cancer patients during radiation therapy. METHODS/SUBJECTS: A total of 72 women with breast cancer (stages 1-3) scheduled for radiation therapy were recruited. DESIGN: Women were allocated upon their preference either to the group receiving reflexology treatments once a week concurrently with radiotherapy and continued for 10 weeks or to the control group (usual care). OUTCOME MEASURES: The Lee Fatigue Scale, General Sleep Disturbance Scale, and Multidimensional Quality of Life Scale Cancer were completed by each patient in both arms at the beginning of the radiation treatment, after 5 weeks, and after 10 weeks of reflexology treatment. RESULTS: The final analysis included 58 women. The reflexology treated group demonstrated statistically significant lower levels of fatigue after 5 weeks of radiation therapy (p < 0.001), compared to the control group. It was also detected that although the quality of life in the control group deteriorated after 5 and 10 weeks of radiation therapy (p < 0.01 and p < 0.05, respectively), it was preserved in the reflexology group, which also demonstrated a significant improvement in the quality of sleep after 10 weeks of radiation treatment (p < 0.05). Similar patterns were obtained in the assessment of the pain levels experienced by the patients. CONCLUSIONS: The results of the present study indicate that reflexology may have a positive effect on fatigue, quality of sleep, pain, and quality of life in breast cancer patients during radiation therapy. Reflexology prevented the decline in quality of life and significantly ameliorated the fatigue and quality of sleep of these patients. An encouraging trend was also noted in amelioration of pain levels.