Dietary Counseling Is Beneficial for the Patient With Cancer

Abstract

The maintenance of good nutritional status during initial treatments for cancer is generally recommended to increase the likelihood of successful completion of prescribed therapies, and possibly to promote improved quality of life during and after that phase of care. In cross-sectional studies, reduced intake and poor nutritional status have been observed to be correlated with poor outcome, but cause and effect cannot be assumed from such observations. Results of a randomized controlled study focused on colorectal cancer patients undergoing radiation therapy reported in this issue of the Journal of Clinical Oncology provide scientific evidence for the benefits of nutritional counseling in the management of these patients. The study confirms that individualized dietary counseling can promote the maintenance of adequate dietary intakes and body weight, resulting in a marked reduction in the incidence and severity of anorexia and diarrhea, and improved quality of life. Most notably, the beneficial effects observed in association with dietary counseling were generally maintained 3 months after the completion of radiation therapy. In this study, various effects of individualized dietary counseling focused on regular foods were compared with the effects of prescribing nutrient-dense, high-protein liquid dietary supplements or ad libitum intake in 111 colorectal cancer patients treated with radiation therapy. The prospective study design allows a comparison of the effects of intervention across the study arms over time, and several types of outcome variables were measured, including symptom severity, health-related quality of life, and nutritional status indicators. Another important characteristic of the study is the inclusion of a study arm that involved prescribing liquid dietary supplements, an approach that theoretically addresses the challenge of maintaining adequate intakes for these patients, but with less intensity or specificity than is achieved with dietary counseling. The randomization was stratified by stage; at baseline, malnutrition was evident only among the patients who had been diagnosed at more advanced stages of colorectal cancer. Measures that were conducted at baseline, at completion of prescribed radiation therapy, and 3 months thereafter included anthropometric measurements, an index of nutritional status based on a multicomponent assessment tool, a detailed dietary history, the presence and degree of symptoms related to radiation therapy (such as anorexia, nausea and vomiting, and diarrhea), and health-related quality of life. The latter was assessed with an established cancer-specific questionnaire that included queries relating to various functions such as physical, cognitive, social, symptoms, and other potential negative results of the disease or condition. The goal of nutrition intervention, in both the dietary counseling and supplement study arms, was to enable the patient to meet the estimated requirements for intakes of energy, protein, and other nutrients, determined by standard calculations. After completion of the prescribed radiation therapy, both the dietary counseling group and the liquid dietary supplement group exhibited an increase in energy intake (averaging an increase of 555 and 296 kcal/d, respectively), whereas the ad lib group reported a decline in energy intake (averaging 285 kcal/d). At 3 months postradiation therapy, the counseling group maintained their intakes, while both of the other groups exhibited a decline at that time point. As a result of these intakes, the patients determined to be malnourished at baseline in the dietary counseling group actually recovered an average 4 kg of body weight at the 3-month follow-up time point. After radiation therapy, only three of 37 patients in the dietary counseling group exhibited a decline from baseline in nutritional status, compared with 19 of 37 patients in the liquid supplement group and 34 of 37 patients in the ad libitum group. In association with good dietary intakes and nutritional status, the dietary counseling group also exhibited the lowest symptom severity score, JOURNAL OF CLINICAL ONCOLOGY E D I T O R I A L VOLUME 23 NUMBER 7 MARCH 1 2005