Anastomotic leakage (AL) remains one of the most serious complications after esophagectomy, and is the main cause of increased risk of postoperative death.[2] In addition, EGAL also affects the long-term prognosis of patients, and the overall survival and disease-free survival of patients with severe anastomotic leakage are significantly reduced. [10] If the possibility of postoperative anastomotic leakage can be evaluated before surgery and active measures are taken to prevent it, postoperative recovery of patients can be promoted. Therefore, this study combined preoperative factors to construct a nomogram to predict the possibility of AL, aid in clinical decision-making regarding treatment selection, and improve patient the prognosis.
The nutritional assessment of patients with esophageal cancer is particularly important, because it is helpful for carrying out reasonable and effective nutritional intervention and treatment, improving the nutritional status of patients with malnutrition, reducing the occurrence of complications, and improving the prognosis. Turrentine et al. showed that preoperative weight loss was positively correlated with an increased incidence of anastomotic leakage.[11] However, there is no specific nutritional assessment tool for preoperative patients with esophageal cancer. Nutrition risk screening (NRS 2002), a nutritional screening tool for hospitalized patients recommended by the guidelines of the European Society for Parenteral and Enteral Nutrition (ESPEN), is the first evidence-based nutritional risk screening tool in the world [12]. Since the 1970s, there have been a variety of nutritional assessment methods such as the Mini Nutritional Assessment (MNA)[13] and Malnutrition Universal Screening Tool (MUST) [14]. However, these nutritional assessment tools have certain limitations, and cannot avoid the interference of subjective assessment. Therefore, the geriatric nutritional risk index (GNRI), a nutritional assessment tool based on objective indicators, can more accurately reflect the nutritional status of patients.[15] Yamana et al. reported the effectiveness of the GNRI in screening for respiratory complications after radical resection of esophageal cancer.[16] Bo et al. reported the efficacy of the GNRI in predicting the prognosis of patients older than 60 years with esophageal squamous cell carcinoma who received radiotherapy.[17] In this study, the GNRI was found to be an independent risk factor for EGAL, which also suggested that preoperative improvement in nutritional status in patients with esophageal cancer can improve the incidence of EGAL.
In addition, this study revealed that age is an independent risk factor for AL, and older patients are more prone to AL. It is speculated that older patients have poor physical condition, often with underlying disease, and weakened organ function, body compensation and tissue repair function, which not only increases the risk of surgery but also increases the likelihood of postoperative complications.[18] In terms of sex, Gao C[19] and Goense L[20] reported that EGAL was related to sex, and the incidence of EGAL in males was significantly greater than that in females. They believed that male sex was usually associated with poor living habits such as smoking and drinking. However, this study revealed no significant relationship between anastomotic leakage and sex. It is speculated that this may be related to the different living habits of people in different regions, which may be one of the reasons why the results of our study are different from those of other studies, but the details still need to be further explored.
Smoking is considered to be a risk factor for EGAL,[21] which is similar to the results of this study. However, the mechanism by which smoking affects EGAL is not fully understood. Previous studies have shown that smoking can cause tissue hypoxia and affect blood perfusion.[22] In addition, long-term drinking invasion of the digestive tract can cause gastrointestinal mucosal ulcers, erosion, bleeding and other injuries, and postoperative anastomotic infection can easily delay tissue healing.[23] Due to the adverse effects of smoking and drinking on perioperative patients, patients should be encouraged to quit smoking and drinking at any time.
It has been well established that cervical anastomosis is more likely to cause EGAL than thoracic anastomosis. A meta-analysis involving 13 centers revealed a significant increase in the incidence of EGAL in the cervical anastomosis group,[24] and another meta-analysis involving four experiments reported similar results.[25] Importantly, reasons are that the cervical anastomosis requires a longer tubular stomach, poor blood perfusion around the anastomosis, and the greater tension of the cervical anastomosis and the superficial position of the neck increases the susceptibility of the anastomosis site to compression and ischemia. Although cervical anastomosis has a greater incidence of EGAL, because of the superficial position of cervical anastomosis, it is easy to detect EGAL earlier and treat it in quickly. In addition, this study revealed that neoadjuvant therapy was not a risk factor for EGAL. Kumagai et al. also reported that neoadjuvant therapy did not increase the incidence of EGAL.[26] However, the timing of surgery after neoadjuvant therapy can affect the occurrence of EGAL and the long-term survival rate.[27] Whether neoadjuvant therapy increases the incidence of postoperative complications in patients with esophageal cancer still needs further study. The nomogram suggested that for patients with advanced age, long-term smoking, heavy drinking, malnutrition and cervical anastomosis, we should pay attention to the possibility of anastomotic leakage after surgery. These patients will be monitored more closely after surgery, including basic vital signs, atrial fibrillation, and daily evaluation of inflammatory indicators. Early upper gastrointestinal radiography and endoscopy are helpful for early diagnosis and targeted treatment.