1.Risk factors for the occurrence of malnutrition
Esophageal cancer patients often suffer from malnutrition and even cachexia due to swallowing difficulties, surgical complications, side effects of radiotherapy, etc. Malnutrition can easily lead to lower quality of life, lower therapeutic efficacy, lower survival rate and poor prognosis. The causes of malnutrition in esophageal cancer patients are complicated and can be divided into two categories: surgery-related and non-surgical treatment (mainly chemotherapy and radiotherapy) related.
Patients with surgical treatment may suffer from pain, weakness, loss of appetite, digestive disorders, etc. Malnutrition will increase the negative impact on wound healing, recovery, postoperative adaptation, infection rate, and hospitalization time. In non-surgical treatment, chemotherapeutic drugs affect firstly the rapidly proliferating cells and secondly the gastrointestinal epithelium.
Chemotherapeutic drugs induce mucositis, enteritis, ulcers, gastrointestinal bleeding, leukopenia, and immune system suppression, which increase the infection rate and increase the metabolic rate of patients. The side effects of radiotherapy include oral mucositis, esophagitis, and painful swallowing, which can lead to malnutrition due to difficulty in eating. Therefore, the impact of nutritional support on the treatment of esophageal cancer has positive significance.
2.Screening and assessment of malnutrition
In clinical practice, a very important issue is how to detect malnutrition at an early stage, which requires us to pay attention to the screening and assessment of malnutrition.
At present, the scales commonly used in clinical practice for malnutrition screening in oncology patients include PG-SGA, SGA, NRI and so on. The screening and assessment of malnutrition in oncology patients is mainly through the doctor’s inquiry about medical history, weight change, physical status, activity, eating condition and adverse symptoms, so as to determine whether the patient has malnutrition. Among them, weight loss is a very important index.
The best nutritional support program is selected according to the different conditions of tumor patients.
3. Nutritional support treatment methods
Clinically, there are two main ways of nutritional support, enteral nutrition and parenteral nutrition.
Enteral nutrition (EN) is a nutritional support method to provide metabolically required nutrients and other nutrients through gastrointestinal tract. The latter includes nasogastric tube, nasoduodenal tube, nasojejunal tube, gastrojejunostomy tube, etc. The characteristics of EN: convenient administration, low cost, physiological, and direct absorption of nutrients through the intestine. In addition, EN has the advantage of helping to maintain the integrity of the intestinal mucosal structure and barrier function.
Parenteral nutrition (PN) is to supply nutrition from intravenous as nutritional support before and after surgery and for critically ill patients, and all nutrients are supplied parenterally, which is called total parenteral nutrition (TPN). Clinically, PN can be combined with EN to improve the nutrition of patients.
4.Impact of nutritional support on the treatment of esophageal cancer patients
4.1 Impact on esophageal cancer patients after surgery
About 50~80% of patients diagnosed with esophageal cancer are accompanied by malnutrition. Malnutrition can increase the risk of postoperative complications, delay postoperative recovery and affect the quality of life. Nutritional support can reduce the incidence of postoperative complications in patients with esophageal cancer, and Ligthart-Melis et al. investigated the effect of enhanced nutritional support (INS) on improving the prognosis of patients with esophageal cancer after surgery. In the first year after enhanced nutritional support (INS) (i.e., March 2009 to April 2010), all patients (n = 28) who underwent surgery were in the INS intervention group. The control group (n = 37) were patients who underwent surgery within three years prior to the start of enhanced nutritional support.
Enhanced nutritional support resulted in a 4.8% increase in preoperative weight compared to control patients (P = 0.009); the study showed that enhanced nutritional support maintained preoperative weight and reduced serious postoperative complications in patients with esophageal cancer.Fujita et al. randomized 154 patients undergoing esophagectomy to either enteral or parenteral nutrition groups; patients who received early enteral nutrition had significantly decreased (P=0.02). In addition, patients who received early enteral nutrition had a higher completion rate of the clinical pathway (P=0.03) and a shorter postoperative hospital stay (P=0.04).
Therefore, the investigators concluded that for patients undergoing esophagectomy, early enteral nutrition reduces the incidence of life-threatening surgical complications and increases the completion rate of the clinical pathway.
4.2 Effect of nutritional support on chemotherapy in patients with esophageal cancer
Chemotherapeutic drugs can cause adverse effects such as myelosuppression, leukopenia, anemia, stomatitis, loss of appetite, nausea/vomiting and diarrhea, which significantly affect patients’ treatment. Reducing the toxic side effects associated with chemotherapy not only relieves pain and the aforementioned adverse effects, but also helps to maximize the efficacy of chemotherapy.
Among them, nutritional support plays a positive role in reducing the aforementioned adverse effects of chemotherapy. hiroshi Miyata et al. showed that the application of enteral nutritional support during chemotherapy in patients with esophageal cancer reduced the incidence of chemotherapy-related hematological toxicity. 91 patients with esophageal cancer receiving neoadjuvant chemotherapy (5-fluorouracil, cisplatin and adriamycin). Randomized to receive enteral nutrition EN (n=47) or parenteral nutrition PN (n=44). The dietary intake of calories during chemotherapy was equal in both groups.
The results showed no significant differences in serum albumin levels and weight changes after chemotherapy between the two groups, and no significant differences in efficacy. However, leukopenia, and neutropenia were significantly less in the EN group than in the PN group.
4.3 Effect of nutritional support on radiotherapy and radiochemotherapy for esophageal cancer patients
Radiotherapy or radiotherapy is an important part of comprehensive treatment for esophageal cancer patients with advanced stage and inoperable. Radiotherapy or radiotherapy can cause radiation esophagitis, ulcerative esophageal perforation, etc., which can lead to reduced feeding and further cause serious nutritional deficiency of patients, and malnutrition can affect the therapeutic efficacy and increase the incidence of complications.
Therefore, nutritional status is an important factor affecting the prognosis of patients with esophageal cancer treated with radiotherapy, and it is necessary to improve the nutritional status of patients by providing nutritional support. The investigators concluded that appropriate nutritional support helps patients with esophageal cancer treated with radiotherapy to achieve the desired outcome.
Based on the significant impact of nutritional support on the prognosis of esophageal cancer, our group has paid attention to the nutrition of patients with esophageal cancer for a long time. In practice, we have worked out different nutritional support programs suitable for different esophageal cancer patients and achieved better results. Our observation shows that reasonable nutritional support can help reduce the adverse effects of chemotherapy and improve the therapeutic efficacy of esophageal cancer patients. We also hope that both patients and doctors should pay close attention to the nutritional support treatment of esophageal cancer patients.