GBC refers to a rare disease, the commonest incursive tumor in the biliary mechanism[1, 15]. Nevertheless, GBC progress rapidly, developing rare early symptom[16]. Accordingly, detection in advance and surgical treating process in advance are upheld [15], whereas GBC prognostic process is still not effective. Accordingly, novel biomarkers for the prognosis of GBC are required. Low GNRI was identified a less effective predicting factor of OS and RFS in GBC patients after they underwent GBC radical surgery.
Serum albumin level and BMI are critical variables capable of reflecting the survival risk in malignancies patients. Serum albumin refers to a highly related malnutrition indicator, effectively indexing cachexia or malnutrition in cancer patients, since this factor is partly suggested by hypoalbuminemia. Nutrition can be employed as a critical factor to determine immune response[17]; For this reason, hypoalbuminemia may show associations with damaged immune response. In comparison, a systematic review revealed that high serum albumin concentration displayed associations with higher cancer patients’ surviving condition [18].
Though a number of works demonstrated an association between obesity and risk of GBC incidence [19], these are also studies that weight of body loss refers to an ineffective prognosis factor of CBG. According to Jinwoo Kang, survival was considerably better in patients exhibiting large BMI in comparison to those exhibiting poor BMI. Furthermore, body weight loss was expected under negative cell regulating mechanisms for cancer or in patients of aggressive cancer. Nevertheless, low BMI or body weight loss refers to a negative prognosis factor for GBC patients[20].
According to Kawai et al., nutrition critically determines immune responses, and malnutrition most frequently leads to immunodeficiency[21]. Furthermore, malnutrition displayed associations with cell-mediated immunity damage for the host defenses resisting cancer. Malnutrition is a state of protein-energy or other nutritional imbalance, as well as a feature of cachexia. Systemic inflammation in the course of tumor progression will result in cachexia in cancer patients. In cancer patients with cachexia, elevated circulating concentrations of a range of inflammatory cytokines were identified[22]. Given the mentioned results, malnutrition is likely to confirm poor outcome even in GBC patients resected in a surgical manner.
The GNRI as relying on body weight loss and serum albumin concentration reveals the nutritional status. Accordingly, the GNRI can assess both of the mentioned variables in the meantime. In addition, GNRI can be simply obtained according to laboratory data achieved routinely and can assess the nutritional status. In fact, in Fig. 2, GNRI exhibited the largest area under ROC curve in comparison to those of BMI and albumin, which is noticeable from the perspective of statistics. Nevertheless, few studies have verified the clinics-based use of GNRI for organ malignancies, expect esophageal cancer[11].
In this study, approximate 51% of patients had GNRI less than 100, though each case appeared to be in sufficient health, according to these patients’ preoperative functional tests results and appearance, for undergoing surgical resection. As revealed by the mentioned result, preoperative GNRI can be adopted to effectively to identifying patients undernourished among all patients with appropriate organ functions and allowed to receive surgery.
In the present study, compared with patients exhibiting large GNRI before surgery, patients exhibiting poor GNRI exhibited larger NLR (P < 0.001), CA19-9 (P = 0.028), incidence of gallstones (P = 0.048) and poorer tumor differentiation. Accordingly, patients exhibiting poor GNRI were likely to show tumor development. For this reason, such variable is likely to be an effective index of high-grade tumor malignancy. Nevertheless, this study cannot draw the conclusion that low GNRI is likely to lead to or be attributed to tumor malignancy according to this work.
Furthermore, by multivariate analysis, poor differentiation, low hemoglobin, high age, low GNRI, lymph node metastases and TNM III + IV were identified as separate prognostic factors in GBC patients. Considering our knowledge, it was first reported in this study that a preoperative low GNRI is a predictive and prognostic factor of GBC, since no existing analyses reported that GNRI is feasible to treat other cancers. Moreover, it was reported that low GNRI patients had considerably shorter OS than high GNRI patients. Accordingly, GBC and low GNRI patients are at high-risk of death even after undergoing therapeutic processes. For this reason, after this type of patients have undergone surgeries, more careful follow-up should be conducted.
Bo et al. reported that the GNRI estimated survival in old esophageal cancer patients received radiotherapy[11]. Given the conclusion drawn by these researchers, the GNRI was a single prognosis factor in elderly esophageal cancer patients underwent radiotherapy. The mentioned data supported the findings of this study as well.
The present study has several limits. Firstly, a retrospective study was carried out in an individual institution, and bias existed, in particular bias of selection. Nevertheless, such bias was restricted by including consecutive patients in a set period. Secondly, in a single cohort, the GNRI’s prognosis implication was tested, as well as its cutoff value. Though the study tends to be overfitting, no other cohort can be presented, or our cohort cannot be split to a training and verification cohort. The results of this study are supposed to be verified in larger single cohorts. Irrespective of the mentioned limits, the first data are presented, revealing the GNRI as a vital prognosis factor in GBC patients. Since the GNRI includes available parameters, the GNRI applies to standard clinical settings.