INTRODUCTION
Malnutrition in patients with colorectal cancer is a significant clinical and nursing problem. Colorectal cancer is a malignant neoplasm, which is one of the most common cancers among the inhabitants of highly developed countries. It develops within the colon, cecum with appendix, sigmoid colon, rectosigmoid junction, rectum, and anus. It manifests e.g. as rectal bleeding (regardless of the moment of defecation), belatedness, the presence of blood and/or mucus in the stools, abdominal pain, urgent or painful straining, and a change in the rhythm of
bowel movements [1, 2].
The basic diagnostic test used to confirm the diagnosis of colorectal cancer is colonoscopy, which enables macroscopic evaluation of the mucous membrane of the entire large intestine, as well as obtaining the material for histopathological examination. After the histopathological diagnosis of colorectal cancer, diagnostics should be carried out to determine the stage of the disease, and then a multidisciplinary consultation should be convened to qualify the patient for appropriate oncological treatment (surgery, chemotherapy, radiotherapy, molecularly targeted treatment).
One of the complications of cancer therapy is malnutrition. According to the definition of the European Society for Clinical Nutrition and Metabolism (ESPEN), malnutrition is a condition resulting from the lack of absorption or lack of consumption of nutrients, leading to changes in body composition, impairment of physical and mental functions of the body, and adversely affecting the outcome of treatment of the underlying disease [3].
According to the available literature, there are 3 forms of protein-energy malnutrition, which are divided as follows:
marasmus type – resulting from chronic starvation; muscle and fat mass decreases, anthropometric and immunological indicators decrease (while the protein concentration in the blood is normal);
*Kwashiorkor type – resulting from infection, significant injury, or surgery; the concentration of protein in the blood decreases, while the anthropometric indicators are normal;
*mixed type – develops in chronically ill patients with marasmus type malnutrition as a consequence of injuries and surgical procedures [4, 5].
Advanced stages of cancer are often accompanied by cachexia, which is defined as a multifactorial syndrome characterised by unintentional weight loss with progressive loss of muscle mass with or without loss of fat mass, which cannot be completely reversed or stopped using conventional methods. nutritional treatment [6–8].
There are 3 stages of cancer cachexia:
1. Pre-cachexia – a condition in which body weight loss is ≤ 5% and metabolic disorders or loss of appetite occur.
2. Cachexia – defined as:
a) weight loss > 5% in 6 months, or
b) weight loss > 2% in patients with a reduced body mass index (BMI < 20 kg/m2), or
c) weight loss > 2% in patients with sarcopaenia. It is common in cachexia,decreased food intake or generalised inflammation.
3. Persistent cachexia – this is a varying degree of cachexia, characterised by active catabolism (procatabolic cancer disease and unresponsive to anticancer treatment) or the presence of factors that make further weight loss treatment impossible or inappropriate.
Persistent cachexia is characterised by a low overall performance status (WHO 3 or 4) and a predicted survival < 3 months [8].
According to Fearon et al., cancer cachexia concerns patients with a loss of > 5% of body weight in the last 6 months or > 2% (in patients with a BMI of > 20 kg/m2), or loss of muscle mass together with a loss of at least 2% of body weight.
The diagnosis of cachexia based on the criteria proposed by Fearon et al. is, among others, recommended by the ESPEN society [8].
The frequency of malnutrition and cachexia depends on the type of cancer, its stage, comorbidities, and the age of the patient. Weight loss affects up to 80% of cancer patients and is often considered an inseparable element of the disease [9]. An important element of the care of oncological patients is the assessment of the nutritional status, which enables the identification of malnourished people and those at risk of malnutrition, the determination of the degree of malnutrition and its cause, and the monitoring of the effectiveness of nutritional therapy [10, 11]. Weight loss in the period before chemotherapy increases the number of complications, shortens the uncomplicated time of treatment, reduces the response rate, and impairs the quality of life [12, 13]. Signs of malnutrition are found in a significant proportion of patients admitted to oncology wards. Patients with diagnosed and treated colorectal cancer are at risk of malnutrition and a decrease in the quality of life, which may result from both the ongoing disease process and the impact of the anticancer therapy itself [14].
The course of cancer treatment is special, both for therapeutic and deontological aspects. Coping with the disease requires the patient to be able to cope with this ever-changing health situation and to consciously accept the interactions between the disease and the changing environment of the patient’s life. The latter circumstance, in turn, can exacerbate the disadvantages created by the emergence of a malnutritional state. The adaptation processes – closely related to the psychological side of the patient – are influenced, among other things, by the information provided in the form of specific messages about the disease, and the phases of development of the latter are undeniably related to the potentially emerging (or intensifying) process of malnutrition. Lack of reliable information about the disease or false information based on stereotypes build maladaptive emotional attitudes towards the disease and the whole treatment process and can directly influence the malnutrition process [15]. A helpful instrument that can provide a foundation for communication between the oncology physician and the oncology patient is, for example, the SPIKES protocol for communicating unhelpful information by Baile et al. It interacts with the standards contained in the Code of Medical Ethics [16].
MATERIAL AND METHODS
The study included 101 patients with metastatic colorectal cancer treated in the Clinical Oncology Department of the Oncology Centre of St. John of Dukla in Lublin. There were 60 men (59.4% of patients) and 41 women (40.6% of patients) in the study group, and the average age of the patients was 67.3 ±10.6 years. 92% (93/101) of the surveyed people were over 51 years old, and most of the patients lived in urban areas (87/101, 86.1% of the study group), had secondary education (55/101, 54.5% of people), and did not perform work due to illness (76/101, 75.2%). Almost all patients declared an average or good socio-economic situation (99/101, 98%), lived with their family (99/101, 98%), and were in a partnership or married relationship (98/101, 97%).
In 26/101 (25.8%) people, cancer was diagnosed within the last 6 months, in 39/101 (38.6%) of the respondents between 6 and 12 months preceding participation in the study, and in 36/101 (35.6%) of patients the disease was diagnosed for more than 12 months. The examined people were most often in a good performance status – Eastern Cooperative Oncology Group-World Health Organisation (ECOG-WHO) grade 1 (78/101, 77.2%), while the most common location of the tumour was the rectum and the sigmoid colon, respectively, in 34.7% (35/101 people) and 28.7% (29/101 people) of patients. The most common site of distant metastases was the liver (in 89/101 patients, 88.1%), and the least frequent were bone metastases (in 6/101 patients, 5.9%).
Table 1 summarises the results of the anthropometric assessment and interview regarding the regularity and quality of the diet used during treatment for colorectal cancer. 89.1% (90/101) of the surveyed people in the interview declared proper fluid intake, i.e. maintaining their volume and regularity throughout the day. 75.2% (76/101) of the patients admitted that they take care of regular consumption of meals, and all the subjects considered that their diet was wholesome. Adverse gastrointestinal symptoms were observed in 31/101 (30.7%) of the subjects, most often nausea (100% of patients with gastrointestinal symptoms) and anorexia (41.9% of patients with gastrointestinal symptoms).
Statistical analysis
The particular stages of the statistical analysis were carried out using the computer program MedCalc version 18.5 (MedCalc, Belgium). The distribution of the values of the examined parameters showed a normal distribution; therefore, parametric tests were used in the analysis. Differences in the values of the examined parameters between patients with different subjective global assessment (SGA) and numerical rating scale (NRS)-2002 classifications as well as changes in BMI and body weight over time were assessed using Student’s t-test for independent and dependent groups, respectively. Comparison of the frequency of individual characteristics of patients depending on the SGA and NRS-2002 classifications was carried out using the Fisher and χ2 test. The correlation of the examined features was tested using the Pearson test. Results with p values < 0.05 were considered statistically significant.
RESULTS
Assessment of nutritional status and risk of malnutrition in patients with advanced colorectal cancer
Results obtained from the evaluation of the subjective global assessment and numerical rating scale 2002 questionnaires
I
n the study group of patients, 77/101 (76.3%) people had normal nutritional status (SGA-A), while 22/101 (21.8%) patients were classified as SGA-B, and 2/101 (1.9%) as SGA-C. 63/101 (62.4%) of the subjects had no risk of malnutrition (NRS < 3), while 38/101 (37.6%) patients had a result (NRS ≥ 3) indicating the risk of malnutrition and the need to consider nutritional treatment. On average, the examined patients obtained 2 points in the nutritional assessment carried out using the NRS-2002 questionnaire (NRS = 2) (Table 2).
Table 3 shows the proportion of patients who lost weight in the 3 months prior to participation in the study depending on the baseline location of the cancerous tumour. It can be noted that weight loss was observed most often in patients with colon cancer (14/19 patients; 73.7%), while it was least frequently reported in the group of people with sigmorectal flexion (4/15 patients; 26.7%). It is worth noting that the differences found were close to achieving statistical significance (p = 0.066).
It was then assessed whether the location and number of metastases are associated with weight loss in patients with advanced colorectal cancer (Table 4).
Weight loss in the examined patients was recorded with a similar frequency regardless of the number of distant organs occupied by cancer metastases (p = 1.0). In addition, there were no differences in the proportion of patients with recorded weight loss depending on the location of metastatic foci in distant organs (p = 0.266).
DISCUSSION
There is a close relationship between cancer (especially colorectal cancer) and risk of malnutrition. The effects of their simultaneous occurrence can be extremely burdensome (and sometimes drastic), causing a deterioration in the quality of life, and sometimes posing a threat to the patient’s life. It is impossible to remain indifferent to such important health problems. In people diagnosed with malnutrition according to the SGA scale, improper fluid intake during the day, lack of regularity of meals, and more frequent side effects from the digestive system are significantly more often noted – compared to people with proper nutritional status; hence, the effects of this type of disorder may directly affect the quality and effectiveness of the treatment process used.
The aim of the above study was to assess the degree of malnutrition of patients with colorectal cancer in the generalised stage in patients treated at the St. John of Dukla Oncology Centre of the Lublin Region in Lublin. The study was conducted from February to March 2023 among a group of 101 patients using the diagnostic survey method with the following research tools: a self-design questionnaire, the SGA scale, the NRS-2002 scale, anthropometric studies, the ECOG-WHO form, skin fold measurement, and medical documentation.
The NRS-2002 and SGA scales are mandatory in Poland in accordance with the Regulation of the Minister of Health of 22 November 2013 on guaranteed services in the field of hospital treatment (consolidated text, Journal of Laws of 2023, item 870, as amended). Pursuant to §6(1) of the said regulation, a service provider providing hospitalisation and elective hospitalisation services subjects all service recipients admitted for treatment, with the exception of the hospital emergency department, to a screening of nutritional status (SGA or NRS-2002 – in adults, on growth grids in children and adolescents), in accordance with the principles set out in the “Standards of parenteral nutrition and enteral nutrition” of the Polish Nutrition Society Parenteral and enteral or, in the case of children, in accordance with the rules set out by the Polish Society of Clinical Nutrition for Children.
In the study group, 23.7% of patients were at risk of malnutrition according to the SGA scale. However, according to the NRS scale, 37.6% of patients obtained a result indicating the risk of malnutrition and the need to consider nutritional treatment.
In the study of Thoresen et al. [17], the nutritional status of 77 patients with solid tumours within the intestines was assessed. The results of the study were similar to those in the author’s study. In the entire study group, it was noted that 34% had the features of malnutrition, 49% had a risk of developing malnutrition, and 39% of the entire study pool had a decrease in muscle mass.
The results of the author’s study were similar and stated that patients characterised by wasting accounted for 25% of all cases. A high risk of malnutrition was found in 43% of the examined people, and 9% of people had normal nutritional status. In 63/101 (62.4%) of the subjects there was no risk of malnutrition (NRS < 3), while 38/101 (37.6%) patients had a result (NRS ≥ 3) indicating the risk of malnutrition and the need to consider nutritional treatment [17].
In a similar study conducted and described by A. Lewandowska, A. Depta³a, and A. Kraszewska, the impact of malnutrition on the quality of life of patients with colorectal cancer was assessed. The study enrolled 60 men aged 18 to 70 years who stayed at the Department of Oncology and Haematology of the Central Clinical Hospital of the Ministry of Internal Affairs in Warsaw. The study group was divided into 2 subgroups: the BN group, whose lean body mass results were within the range of the norm appropriate to age and sex, and the BO group, in which the amount of lean body mass turned out to be reduced compared to the values considered normal. In both groups, the risk of malnutrition was demonstrated – only 28% of patients from the BN group and 14% of patients from the BO group presented normal nutritional status [18].
Also, in the article prepared by Viana et al., in which the risk of malnutrition and nutritional symptoms in a group of surgical patients with cancer was clearly demonstrated, only 40% of patients presented a proper nutritional status – 37.8% of people were exposed to malnutrition, and 22.2% of people were severely malnourished. Most of the patients (90.4%) had nutritional interventions [19].
Dziewiatowska et al. in an article devoted to the causes of malnutrition (especially in the case of liver dysfunction), noted that patient malnutrition is associated with insufficient food supply, co-occurring digestive and absorption disorders, as well as impaired liver function [20].
In their research, Szczepanik et al. specified that reduced food supply is associated with developing anorexia and impaired absorption and an increase in energy expenditure. As a result of biochemical processes, insulin resistance of tissues develops [9].
Szczepanik et al. also paid attention to the secondary consequences of malnutrition, i.e. an increase in the frequency of infections, disorders in wound healing, an increase in the duration of treatment, and sometimes even – as mentioned earlier – an increase in mortality [9]. Importantly, he also noticed the consequences of malnutrition, which make their mark on the psychological side of the patient, i.e. apathy (which can also be associated with depression), irritability, loss of strength [9]. In research conducted by Tokajuk et al. [21–23], which refer to the results obtained by K³ęk et al. and Kemik et al., other complications are also mentioned, i.e. a wide spectrum of possible infections, liver and kidney dysfunction, oedema, as well as the formation of a mechanism of mutual coupling (a patient who develops complications may consequently continue to consume less food, which causes a deepening of the state of malnutrition) [22, 23].
In the aforementioned study of Lewandowska’s syndrome, the most common ailments that may be an obstacle to eating meals were recurrent nausea (70% of all patients) and change in taste (50%). Less frequently were vomiting (32%) and diarrhoea (25%) [17]. In turn, in the research results presented in the work of Viana et al., as many as 51.8% of patients experienced more than 3 nutrition-related symptoms – these were, among others, lack of appetite (34.8%), nausea (36.3%), constipation (32.6%), vomiting (25.2%), change in taste (28.1%), and dry mouth (41.5%) [18].
In contrast, in our own study, the most common gastrointestinal adverse reactions were nausea (30.7%) and anorexia (41.9%). At the same time, most patients reported proper fluid intake (89.1%) and regular meals (75.2%). It can be concluded that the diagnosis of cancer, especially colorectal cancer in the generalised stage, is directly associated with a high risk of malnutrition, it increases the cost and duration of hospitalisation, and it worsens the prognosis of patients, while significantly reducing the quality of their everyday life. In some cases, it is justified to introduce parenteral nutrition before the start of chemotherapy to avoid the development of cancer wasting syndrome, which in the short term can even lead to death [21, 24, 25].
It is reported that malnutrition generally affects from 30% to as much 85% of oncological patients, and every fifth of them does not die from cancer but from malnutrition. A patient who is better nourished tolerates treatment much better and has better results, and from the point of view of therapy, it is possible to give this treatment greater dynamics and effectiveness. Hence, it is important to prevent malnutrition and develop new methods of a multidimensional view of problems related to cancer treatment (TARGET method) [21, 25]. It is impossible not to agree with Tokajuk et al., who in their research emphasised that the TARGET method should be used as widely as possible in the treatment of cancer patients who are at risk of malnutrition. That approach includes education of medical staff in the field of malnutrition (teaching), awareness of the negative impact of cancer wasting on the course of the disease and treatment (awareness), recognition criteria, the concept of genetic predisposition to the occurrence of cachexia-anorexia syndrome (genetics), the beneficial role of prevention and physical exercise in the early phase of cachexia (exercise/early intervention), and the use of appropriate, multidimensional therapy (treatment) [21].
Guided by the need for a holistic approach to the patient, both to their physical and mental side, it is necessary to provide them with the right context of functioning in the disease. This has been noticed in numerous documents relating to issues related to the proper coexistence of a patient treated for cancer and an oncologist. The European Code of Cancer Practice of 2020 explicitly guarantees oncological patients the right to the best possible quality of life (also during treatment) and to receive integrated treatment (including supportive treatment), which undoubtedly applies to both preventing and combating the effects of malnutrition [25]. The code of medical ethics (KEL) stipulates that a doctor should treat patients kindly and culturally, respecting their personal dignity, and their right to intimacy and privacy (Article 12(1) KEL). It is also worth mentioning the content of Article 16(1), second sentence, of KEL indicates that informing the family or other persons should be agreed with the patient (with the proviso that the patient is not unconscious or underage, as in such cases different rules apply). Article 17 in turn stipulates that, in the event of an unfavourable prognosis for the patient, the doctor should inform the patient of this with tact and care. The information about the diagnosis and poor prognosis may not be communicated to the patient only if the doctor is firmly convinced that its disclosure will cause very serious suffering to the patient or other adverse health consequences (such as, inter alia, deterioration of the mental state, which may consequently lead to a state of malnutrition). However, at the patient’s express request, the doctor should provide full information. It also generally establishes the rule that a doctor may not inform a patient about his or her state of health or treatment if the patient wishes to do so (Article 16(1) KEL). This rule suffers a limitation when the patient is unconscious or underage (Article 16(2-3) KEL). It is the physician’s duty to respect the patient’s right to informed participation in decisions concerning their health, and the information provided to the oncology patient should be formulated in a way that the patient understands (Article 13(1-2) KEL). The relationship between the patient and the doctor should be based on their mutual trust, and, as is well known, this is not an immediate state, but a relationship built on the basis of a combination of competence and communication (Article 12 KEL). In spite of this, the treating physician must also not object to the patient consulting another physician about his or her condition and medical management, and they should even facilitate such consultation at the patient’s request (Article 18 – Article 20 KEL) [26]. The SPIKES protocol mentioned in the introduction (S – setting, P – perception, I – invitation, K – knowledge, E – emotions and empathy, S – strategy and summary) interacts with the rules contained in the Code of Medical Ethics. Especially the coupling occurring between the following: K – knowledge, E – emotions and empathy, S – strategy and summary, builds a relationship of trust between the patient and the oncologist, while minimising the negative effects of psychological interactions that can lead to an undesirable state of malnutrition.
CONCLUSIONS
The occurrence of disseminated colorectal cancer is associated in patients with the appearance of gastrointestinal ailments, primarily nausea and anorexia. In the study group it was found in every third patient. Half of the patients experience weight loss during treatment, mostly due to malnutrition.
Weight loss associated with advanced cancer and treatment may be related to the primary location of the cancerous tumour – the paper obtained a result close to statistical significance, suggesting that more often than in other patients weight loss is observed in people with colon cancer. Studies, on the other hand, did not directly show a direct relationship between weight loss and the location of metastases and the number of organs involved in metastases. It seems that weight loss and decrease in BMI may be dependent on the location of the primary tumour – a decrease in their values was most often observed in patients with colon and rectal cancer. However, the results of the conducted studies did not confirm the correlation between an increase in tumour mass and greater cachexia.
In people diagnosed with malnutrition according to the SGA scale, improper fluid intake during the day, lack of regularity of meals and more frequent side effects from the digestive system are significantly more common than in people with proper nutritional status, which may lead directly to a weakening of the quality and effectiveness of the treatment process. Malnutrition diagnosed according to the SGA scale was found among the examined patients with a similar frequency in both sexes. However, it was found that the risk of malnutrition in patients with metastatic colorectal cancer according to the NRS-2002 scale occurs significantly more often in older people, especially those over 67 years of age.
In clinical practice, the need for the widest possible implementation of multidimensional treatment of patients with colorectal cancer is recognised, taking into account the risks and effects of malnutrition (including those relating to the mental sphere). At the same time, it seems necessary to make medical personnel and oncological patients aware of their ethical and legal guarantees to achieve the best possible quality of life, including through the prevention and treatment of malnutrition. It is crucial in this respect to follow the correct rules of communication and, consequently, to build a relationship of trust between the oncology patient and doctor. Aspects related to the correct form of conveying unfavourable information translate directly into the psychological state of the oncology patient and the occurrence of possible adverse effects, e.g. in the form of a state of malnutrition corresponding to the patient’s psychological state.
DISCLOSURES
1. Institutional review board statement: Not applicable.
2. Assistance with the article: None.
3. Financial support and sponsorship: None.
4. Conflicts of interest: None.
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