Journal of Food Processing & Technology

Implementing Nutrition in Cancer Care

Călescu Roxana^* Dietitian, Medical Oncology, The Clinical Hospital Coltea, Bucharest, Romania
^*Correspondence: Călescu Roxana, Dietitian, Medical Oncology, The Clinical Hospital Coltea, Bucharest, Romania, Email:

Received: 01-Jun-2020 Published: 10-Jul-2020, DOI: 10.35248/2157-7110.20.11.830

Introduction

Cancer treatment is the main factor that influences many of the changes in the patient ’ s diet. Having side effects due to a treatment can really make you have a hard time in choosing the right food and getting advice from a dietician is exactly what you need.

Many people skip or avoid for a long time many nutritious dishes just because they know what they have to avoid, but not what to replace them with. Nobody knows that better than a dietician, whom not only will tell you what to eat instead, but also the exact amount and frequency of the foods you have to include in your diet when you are feeling sick (e.g., nausea, vomiting, diarrhoea, constipation).

It is helpful to have a weightier that measures the skeletal muscle mass, fat mass and metabolic rate in order to understand the changes that are happening at every examination, and to know what should be increased in the diet plan (proteins, fats, lipids, vitamins, minerals).

There are different types of patients in cancer when it comes to nutritional status. The first category, and unfortunately the most common one found in head and neck, lung and gastric cancer is cancer related malnutrition, a fast and hard to reverse weight lost, in which a dietician should fight first for maintaining the patient’s actual weight if he has lost ~5% in the last 6 months.

The second one would be the patients; mostly females treated for breast, endometrial and ovarian cancer which either gains or maintain an overweight or obese Body Mass Index (BMI). This means that you could find some common points in many of the patients, if we widely analyse them, but when it comes to eating each and every of them have different preferences, numbers of meals, quantities of food, foods that they like or dislike, food restrictions due to their diagnosis but not last, appetite influenced by the side effects of their cancer treatment.

Results and Discussion

The number of newly cancer diagnosed in 2017 was 1.7 million new cases [1], but cancer screening, early detection and treatment have reduced the annual number of deaths to 600.920 in the same year [1,2]. In order to manage complications due to disease focus has been increased on ameliorating symptoms through the cancer evolution [3].

The main aim of cancer treatment is to heal, monitor or alleviate, and on the other hand the role of nutritional support through the cancer pathway is to manage the needs and treatment goals [1-4]. All cancer patients may encounter malnutrition through the cancer trajectory even since the diagnosis [5,6]. Malnutrition has been identified in 15%-20% of all cancer patients at diagnosis, in 80% of those with advanced cancer, and (85-90)% of patients in terminal phase [7,8]. Malnutrition has been related with reduced response to chemotherapy, a negative impact on quality of life, and high mortality [9,10] being the cause of death in cancer of (20-30)% cases [7,8]. Losing 5% of the initial body weight before the diagnostic or starting the treatment has been predictor for early death no matter the cancer stage [10-12].

The main reasons of the risk for malnutrition in cancer and cancer related treatment are higher request for energy, which leads every biological response and all primary processes of the human body, including cardiopulmonary and immune responses [2,7].

The Academy of Nutrition and Dietetics and American Society of Parenteral and Enteral Nutrition defined malnutrition as having ≥ 2 of the following characteristics: lowered energy intake, weight loss, waste of muscle mass, waste of subcutaneous fat, edemas and lowered performance status by hand grip strength [13].

The mechanism of cancer is represented by hyper metabolic changes by releasing catabolic hormones and inflammatory cytokines that hold back protein synthesis and make increasing the lean body mass more difficult (e.g., ubiquitine-proteasome, complex acute-phase proteins, IL-6) [14-18]. In some types of cancers, functional and mechanical issues may impair the ability to eat or absorb nutrients (e.g., gastrointestinal and head and neck cancers) [15,19]. Some of the patients have different eating habits, appetite, culture and perception of tastes depending on the area they come from [20]. The initial nutritional status before diagnosis is important because patients may require additional macronutrients (carbohydrates, proteins, fats) and micronutrients (vitamins and minerals) before and during treatment. Higher initial intake of soy protein, omega-3 fatty acids, green tea, tomatoes have been associated with reducing cancer risk, compared to higher animal fat and beta-carotene that showed increased risk [14].

The type of treatment recommended for treating cancer (e.g., surgery, chemotherapy, radiation, hormone therapy, immunotherapy, biological therapy, target therapy, transplantation, or any of them combined) can affect appetite, taste, absorption, and loss of nutrients. Treatment’s side effects, like mucositis, nausea or vomiting, diarrhoea or constipation enhance the risk of malnutrition [21].

The National Comprehensive Cancer Network created a Palliative Care Guideline in which cancer cachexia and anorexia have been recognized as a concern of palliative care [13]. Diagnosing pre-cachexia or mild cachexia at its early-onset could help clinicians in to prevent moderate or severe cachexia [22-24].

Cancer cachexia is the type of progressive syndrome manifested by systemic inflammation, continuously waste of skeletal muscle mass (with or without waste of fat mass) with a negative protein/ energy balance [16]. Cancer cachexia is characterized by anorexia and weight lost and cannot be completely reversed by the conventional nutrition counselling [13,17]. Finally, cachexia leads to generalized weakness, cardiorespiratory weakness, delayed wound healing, affected immune system and on-going functional impairment [15,16,21].

Globally, it is estimated that ~2 million people will die every year due to the consequences of cancer related cachexia. Cachexia can be found in approximately 50% of all cancer patients, and is characterized by severe body weight lost, with skeletal muscle proteins waste of approximately 75% when the patients already lost 30% of body weight. Muscle wasting is one of the most important phenotypic characteristic of cancer cachexia, even though not much success has been achieved in reversing or preventing this catabolic process. When we talk about the elderly, the combination of age-related muscle loss (sarcopenia) and cancer diagnosis (with cachexia at the disease onset) is considered a metabolic challenge that older skeletal muscle is not able to do because of metabolic abnormalities like increased glucose turnover, increased lipolysis and insulin resistance, deregulated hormone housekeeping (hypogonadism), decreased muscle protein net balance, elevated cytokines and elevated acute-phase protein synthesis [25]. All of these factors can cause metabolic syndrome in the nutritionally compromised elderly, with the concomitant impairment of cancer therapy and quality of life. Therefore, it is needed that physicians and scientists to insure targeted nutritional support offered by a RDN in order to control the involuntary weight loss and death through the cancer treatment [26].

There have been eyes set on cancer survivors agreeing that reducing the recurrence of the disease consists in a healthy lifestyle based on healthy diet, normal weight and exercise in order to reduce cancer recurrence and death [27]. In order to do so, the nutrition experts, RDNs are well prepared to advice the patients in order to implement and apply healthy lifestyle interventions for those at high-risk for developing cancer, for cancer patients and for those who survived cancer. Early implementation of nutrition has benefits in improving quality of life and reducing future cancer risks [28]. RDN’s working with cancer patients have to develop specific knowledge, information, competencies and venue in order to provide safe and effective nutrition support in each stage of cancer (prevention, treatment and survivorship) [29].

An RDN has to provide oncology nutrition and dietetics care and services, to self-evaluate hers or his proper knowledge, information and venue in order to assure a safe and effective oncology nutrition and dietetics practice, to improve the topics in which better knowledge, information and venue are needed to become a competent, proficient or expert practitioner of oncology nutrition and dietetics. RDN’s must also create a base for public and professional accountability in oncology nutrition and dietetics support and facilities; sustain efforts for strategic planning, achievement and notification of oncology nutrition and dietetics facilities and resources; improve professional identity and ability in communicating the kind of oncology nutrition and dietetics care and services; to control the development of oncology nutrition and dietetics related education and on-going education programs, job descriptions, practical guidelines, skills evaluation tools and career pathways; and to attend educators and preceptors in teaching students and interns the knowledge, competencies and venue needed to work in oncology nutrition and dietetics and the understanding of the full role of applying it in cancer care [30].

A RDN can help patients with hyper metabolic conditions, such as cancer or undergoing cancer treatment [31]. The first step is to provide them more proteins, which are the main source of calories used in energy conversion. In order to manage hyper metabolism that occurs in stress and illness, patients need additional proteins [31]. Calculating the caloric/energetic needs for adults are assessed by current condition and custom body weight. A healthy person normally needs (25-30) kcal/kg/day; those that have to gain weight need (30-40) kcal/kg/day, while obese ones need (21-25) kcal/kg/day [8,31]. Another thing that must be taken in consideration is hydration because of the electrolyte balance, which maintains normovolemia and avoids dehydration [6,8]. Modalities of measuring hydration status are weight measurement, intake/discharge, edema, skin analyses, oral analyses and respiratory status [32]. Moderate dehydration can make patients manifest fatigue, xerostomia, dizziness, constipation and nausea amplified by cancer and treatment specific side effects such as nausea¸ vomiting¸ diarrhoea, ascites and fever [33]. The calculation of the fluid needs is (30-35) ml/kg.

When it comes to intervening with nutritional support the cancer type and stage are taken into consideration, as well as the treatment applied [8,34]. Two important targets of nutritional therapy are maintaining adequate calories, proteins, fluids, general nutrition status and preventing or dealing with cancer treatment side effects [3]. Early nutritional support identifies patients at risk of malnutrition and avoids nutritional impairment as encountered in cachexia [6].

Promoting a good nutritional support through the cancer pathway is equivalent with preventing malnutrition. The nutritional support must be centred on physical evaluation, weight monitoring, appetite, gastrointestinal modifications such as nausea, vomiting, diarrhoea, mucositis, and constipation [8]. Healthy diet with an adequate intake of proteins and proper hydration, combined with physical activity, of 150 minutes of moderate activity every week, are key factors for a longer survival [34]. If at the implementation of the treatment the patients are malnourished, the amount of protein calories must be increased [8,35]. The simplest way to achieve this target is by eating 6 small meals through the day with an adequate hydration. If nutritional requirements are not accomplished, the traditional oral supplements (e.g., Boost, Boost Control, Glucerna, Nutricomp, Nutridrink) might not be suitable because of the high amount of fructose and the gastrointestinal effect of carrageenan [31,36]. Organic supplements with a lower sugar content and carrageenan free provide better quality as protein source. Protein can be added in cooked meals as pea protein, hemp or whey supplements [8,34]. There are patients that believe certain foods can heal cancer. A RDN must modulate this discussion toward healthy diet, proper energy/protein intake and prevention of muscle atrophy and deconditioning due to the disease [35,37].

There are studies that show a lower risk for some cancers and chronic disease (e.g., heart disease, diabetes) [38-42] by consuming a variety of fruits, vegetables, seeds, legumes, whole grains, herbs and spices. These aliments are rich in antioxidants (vitamin A, C, E) that could pre- vent cancer and cellular deterioration. Care is needed, anyways, because of the concerns that antioxidants may lower the efficiency of some cancer treatment [43]. Before the use of any antioxidant it is better to communicate with the oncologist.

There are patients that during the cancer treatment don ’ t experience weight lost. Some of them were obese at the disease onset and can keep gaining weight. Obesity, especially abdominal, is a factor of risk in cervical, oesophageal, postmenopausal breast cancer, pancreatic, renal, colon and rectal cancer [3,41]. The abdominal obesity is associated with insulin resistance, increased insulin production, therefore increased cancer chance. Obesity is considered a factor of developing comorbidies or secondary cancers, and a weight loss diet could be appropriated. The ideal weight lost is maximum 1 kg per week, and special monitoring of body nutrient necessities meanwhile losing weight and following cancer treatment is required [3].

There is a concept in the medical practice and care that “sugar feeds cancer ” . By this we can understand that glucose is a mediator in the tumor metabolism by promoting cancer cell growth and division. The truth is that cancer cells normally use glucose with a higher rate than noncancerous cells, but this doesn ’ t mean that patients should take into consideration eliminating glucose or simple sugars (carbohydrates). This could even be a challenge for many patients, because carbohydrates provide the biggest proportion of the U.S. Recommended Daily Intake (RDI) from all macronutrients (carbohydrates, fats and proteins). When it comes to healthy individuals, the total daily caloric intake should be 20%-35% provided by fats, and approximately 50%-60% coming from carbohydrates. There is a contradiction between scientists when it comes to the appropriate RDI of proteins, although the current recommendation remains at 0.8 g/kg. The contradictions are focused on protein intake of healthy individuals, but little attention on the nutritional needs of the patient with cancer, no matter the age.

The plasma levels of all the essential amino acids (AAs, expecting tryptophan, and in some cases threonine) are lower than normal in patients with cancer [44-52], which shows inadequately nutritional intake. When it comes to the American Society for Parenteral and Enteral oncology patients, the recommendation is minimum daily protein supply of 1 g/kg body weight, and target supply of (1-1.2) g/kg. The argument for increased intake of protein and amino acid (AA) sources in cancer patients is simple: providing an anabolic stimulation on the skeletal muscles in moments when it is exposed to a higher rate of breakdown because of the cancer and tumor related factors [53].

When it comes to cancer and aging, the stimulation of the muscle protein synthesis can be achieved by adding amino acid (AA) such leucine, which is the principal nutrient responsible for the stimulation of muscle protein synthesis [54], to highprotein supplements [55-57], or well-adjusted meals with a lean protein source [58]. It is known that the difference exists in the time course of the anabolic response to nutritional support related to age, the ingestion of amino acid (AA) acutely [59-61] and chronically [62] stimulates muscle protein anabolism [63] in healthy older adults. By the use of isotopic methodologies and tracer of phenylalanine, one study showed that 40 g of mixed amino acids (AAs) given in small amounts to avoid gastrointestinal side effects stimulates muscle protein synthesis in a mix of younger and older patients with ovarian cancer [64].

Skeletal muscle anabolism in response to an amino acid (AA) supply in healthy elderly individuals can be solid, taking in count the degree of skeletal muscle anabolic resistance with aging [65-67] to amino acids (AAs), which can be valid in the case of elderly with cancer disease. The metabolic response in elderly with cancer is slower and affected compared to healthy elderly or younger cancer patients [64].

Conclusion

Implementing nutrition in cancer care is a major key to support the patient’s tolerance through all stages and types of therapy. Even though studies show inconclusive results or evidence when it comes to certain supplements formulas, higher attention is required on food intake.

A RDN must consult cancer patients after they have visited their oncologist and help them implement the proper diet for their cancer diagnosis and related diagnoses (e.g., diabetes, hypertension, gout, etc.).

Cancer treatment is the main factor that influences many of the changes in the patient ’ s diet. Having side effects due to a treatment can really make you have a hard time in choosing the right food and getting advice from a dietician is exactly what you need.

In order to understand and apply the nutritional indications correctly a personalized diet with all the meals of the day and the proper quantities should be delivered to the patient and explained.

If the patient can’t keep up with the diet for different reasons besides treatment’ s side effects or other oncological causes (e.g., dysphagia, odynophagia, total gastrectomy, etc.) and shows signs of depression he must be directed immediately to a psychologist for therapy. Being depressed can also make the patient neglect the meals and to back up not only when it comes to nutrition, but also dispense cancer treatment and lose touch with the medical team.

Therefore, a cancer patient needs to be treated by more than one specialist in order for him to follow the treatment with fewer complications than usually expected or seen in previous patients. Offering the patient ’ s multimodal supporting (treatment, nutrition, and psychology) can make him understand his diagnosis better and motivate him to continue the battle with cancer by creating better quality of life and emotional stability, all from his medical care team.

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