Abstract
Background/Aim: There are few reports on the clinical significance of the geriatric nutritional risk index (GNRI) in patients with locally advanced rectal cancer who undergo preoperative chemotherapy (NAC, neoadjuvant chemotherapy) followed by radical resection; this study examined the relationship between preoperative GNRI, postoperative complications, and prognosis in these patients. Patients and Methods: Fifty-seven patients with rectal cancer who underwent radical resection after NAC at Osaka University Hospital between November 2011 and May 2018 were included. The GNRI was calculated as follows: GNRI= [1.489×serum albumin level (g/l)]+[41.7×present/ideal body weight (kg)]. Patients were classified into high (GNRI ≥96.74; n=36) and low GNRI (GNRI <96.74; n=21) groups, based on the results of the receiver operating characteristic curve analysis. Results: The Kaplan–Meier analysis showed that the low GNRI group had a significantly poorer cancer-specific survival (CSS) and a poorer overall survival tendency than the high GNRI group. In the univariate analysis, venous invasion, lymphatic vessel invasion, and low GNRI were significantly correlated with CSS; depth of tumor invasion, lymph node metastasis, and lymphatic vessel invasion were significantly correlated with disease-free survival (DFS). In the multivariate analysis, there were no significantly poor prognostic factors for CSS and DFS. Conclusion: Preoperative GNRI may be a useful predictor for recurrence and poor prognosis in elderly patients with rectal cancer who undergo radical resection after NAC. Further studies and accumulation of cases should investigate the relationship between preoperative GNRI and prognosis after NAC in elderly patients.
Malnutrition is reportedly related to cancer prognosis, and various indices have been used to measure this relationship (1). Bouillanne et al. reported that the geriatric nutritional risk index (GNRI), which is based on serum albumin levels (ALB), present body weight (PBW), and ideal body weight (IBW), is a simple nutritional screening tool for predicting the risk of nutrition-related complications and mortality in elderly patients (2).
It has been reported that the GNRI is a useful predictor of recurrence and mortality after radical resection in elderly patients with colorectal cancer (3). In addition, it has been reported that preoperative GNRI is associated with postoperative complications and prognosis not only in elderly patients but also in patients with hematological tumors and solid tumors (4-6). In recent years, curative resection after preoperative treatment for locally advanced rectal cancer has been performed; the expected outcome is tumor reduction. However, clinical trials are still underway.
There are few studies on the clinical significance of GNRI in patients who undergo radical surgery after preoperative chemotherapy [neoadjuvant chemotherapy (NAC)] for locally advanced rectal cancer. In this study, we examined the relationship between preoperative GNRI, postoperative complications, and prognosis in patients with rectal cancer who underwent radical resection after NAC.
Patients and Methods
Patients and datasets. Patients with rectal cancer who underwent rectal resection or rectal amputation after NAC were retrospectively selected from 370 patients with rectal cancer who underwent surgery at Osaka University Hospital between November 2011 and May 2018. Patient exclusion criteria were: 1) recurrent surgery, 2) multiple primary cancers, 3) preoperative chemoradiation, 4) transanal endoscopic microsurgery, and 5) insufficient pathological findings or preoperative laboratory data.
We collected the following information from the patients’ medical records: clinicopathological factors such as age, sex, body mass index (BMI), albumin (ALB), white blood cell count, C-reactive protein (CRP), carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), location of primary tumor, distant metastasis, pathological findings, and postoperative complications.
Preoperative blood samples, height, and weight were measured within 7 days before surgery. Clinicopathological factors were classified according to the 8th edition Union for International Cancer Control Tumor–Node–Metastasis (TNM) classification (7). Postoperative complications were classified using the Clavien– Dindo (CD) classification; only patients with CD Grade ≥II were included in this study (8).
All patients were followed up postoperatively according to the Japanese treatment guidelines. Tumor markers (CEA and CA19-9) were evaluated every 3 months. Computed tomography was performed every 3-6 months, while colonoscopy was performed every 1 to 2 years.
Nutritional assessment using GNRI. The GNRI, calculated using ALB, present body weight (PBW), and ideal body weight (IBW), is a simple screening tool for nutrition-related complications and mortality in elderly patients. The IBW was calculated as follows: IBW=(height in meters)2 ×22. The formula for GNRI was obtained from previous reports; it was as follows: GNRI=[1.489×serum albumin level (g/l)]+[41.7×PBW/IBW (kg)] (2). We classified patients into two groups according to the receiver operating characteristic (ROC) curve analysis based on complications (CD grade ≥III).
Statistical analysis. Continuous variables were expressed as means±standard deviation values. Differences in clinicopathological factors and complications between the GNRI groups were analyzed using the chi-square test or Fisher’s exact test. Continuous variables with parametric distributions were analyzed using Student’s t-test or analysis of variance.
Overall survival (OS), disease-free survival (DFS), and cancerspecific survival (CSS) curves were plotted using the Kaplan–Meier method and compared using the generalized log-rank test.
Univariate and multivariate analyses were performed using a Cox proportional hazards regression model to identify independent risk factors for CSS and DFS (9). Statistical significance was defined as two-sided p<0.05. All statistical analyses were performed using JMP software version 16 (SAS Institute Inc., Cary, NC, USA).
Ethical review. This study was approved by the Research Ethics Committee of Osaka University (approval number: No. 15144-6) and was conducted in accordance with the Declaration of Helsinki. Informed consent was obtained from all the study participants.
Results
Patient characteristics. Thirty-four (59.6%) men and 23 (40.4%) women were enrolled into the study. The median age was 64 years (range=40-79 years). Twenty (35.1%), nine (15.8%), 20 (35.1%), and eight (13.3%) patients had tumors with pathological stages I, II, III, and IV, respectively. The patients with Stage IV tumors had liver metastases, lung metastases, extra-regional lymph node metastases, and peritoneal dissemination. Thirty (50.6%) patients had CD Grade ≥II postoperative complications, of whom 9 (15.8%) had CD Grade ≥III complications.
Distribution and classification of the GNRI. The overall mean preoperative GNRI was 98.9±7.9. There were no differences in the preoperative GNRI distribution according to sex and age (>65 years or <65 years of age) (Figure 1). The mean GNRI was 99.0±8.2 in men and 98.6±7.6 in women. There was no significant difference in the preoperative GNRI between the sexes (p=0.820) (Figure 1A).
Distribution of the geriatric nutritional risk index (GNRI) according to (A) sex (male or female) and (B) age (over 65 or under 65).
Given that the GNRI is used for the nutritional assessment of elderly patients (>65 years) and has been reported to be associated with postoperative complications and prognosis, we compared the two groups (over 65 and under 65). The mean GNRI values were 97.5±6.8 and 99.9±8.6 for the over 65 and under 65 groups, respectively. There was no significant difference in the preoperative GNRI between the two groups (p=0.196) (Figure 1B).
The GNRI was first reported by Bouillanne et al. They classified elderly patients into four groups: a no-risk group (GNRI >98), a low-risk group (GNRI: 92-98), a moderate-risk group (GNRI: 82-92), and a high-risk group (GNRI <82). The ROC curve analysis of postoperative complications (CD Grade ≥III) showed that the optimal preoperative GNRI cutoff value was 96.74 (area under the curve=0.539, sensitivity=0.889, specificity=0.417) (Figure 2).
Receiver operating characteristic (ROC) curve analysis of the geriatric nutritional risk index (GNRI) for postoperative complications (Clavien–Dindo Grade ≥III) in elderly patients with rectal cancer.
Based on previous studies and the ROC analysis, we classified patients into a high GNRI (GNRI ≥96.74) group (36 patients, 63.2%) and a low GNRI (GNRI <96.74) group (21 patients, 36.8%), instead of the four classifications of Bouillanne et al. The relationship between GNRI status and clinicopathological factors in the entire study population is shown in Table I.
The relationship between geriatric nutritional risk index (GNRI) status and clinicopathological factors in all patients.
There were no significant differences in age, sex, preoperative CEA, preoperative CA19-9, degree of differentiation, depth of tumor invasion, distant metastasis, venous invasion, TNM stage, CD Grade ≥II postoperative complications, and CD Grade ≥III postoperative complications between the high and low GNRI groups. However, there were significant differences in BMI, preoperative ALB, preoperative CRP, lymph node metastasis, and lymphatic vessel invasion between the two groups.
Postoperative complications (CD Grade ≥II) (Table II). Thirty patients had CD Grade ≥II postoperative complications. The complications included dysuria (12 patients), ileus (6 patients), catheter infection (4 patients), anastomotic leakage (3 patients), compartment syndrome (2 patients), surgical site infection (2 patients), neuropathy (2 patients), postoperative bleeding (1 patient), urinary tract infection (1 patient), and others (6 patients). The occurrence of surgical site infection tended to be higher in the low GNRI group than in the high GNRI group (p=0.066).
The relationship between geriatric nutritional risk index (GNRI) status and. postoperative complications (Clavien–Dindo Grades ≥II and ≥III).
Survival analysis and poor prognostic factors. The median follow-up duration was 54.1 months (range=3.8-110.8 months). We examined OS, CSS, and DFS in the survival analysis. OS tended to be significantly worse in the low GNRI group than in the high GNRI group (p=0.068). CSS was worse in the low GNRI group than in the high GNRI group (p=0.017). In contrast, DFS was not significantly different between the two groups (Figure 3).
Kaplan–Meier analyses of overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS) according to geriatric nutritional risk index (GNRI).
The results of the univariate and multivariate analyses of the clinicopathological factors for CSS and DFS are found in Table III and Table IV. In the univariate analysis, venous invasion (p=0.032), lymphatic vessel invasion (p=0.039), and low GNRI (p=0.046) were risk factors for poor CSS.
Univariate and multivariate analyses of prognostic factors for cancer-specific survival (CSS).
Univariate and multivariate analyses of prognostic factors for disease-free survival (DFS).
In the multivariate analyses using a Cox proportional hazards model, no independent prognostic risk factor for CSS was identified. Similarly, in the univariate analysis, depth of tumor invasion (T3 and T4) (p=0.030), lymph node metastasis (p<0.001), and lymphatic vessel invasion (p=0.003) were risk factors for poor DFS. In the multivariate analyses using the Cox proportional hazards model, no independent prognostic risk factor for DFS was identified.
Discussion
Our results showed that preoperative GNRI was associated with prognosis and may be a useful marker in patients with locally advanced rectal cancer who undergo radical resection after NAC.
Malnutrition is a significant risk factor for postoperative complications and mortality in patients with malignant tumors and has been reported to be associated with prognosis (10, 11). Some nutritional indices, such as the prognostic nutritional index, platelet-lymphocyte ratio, and modified Glasgow prognostic score, have been used to predict postoperative complications and long-term prognosis of cancer (12-15).
Buzby et al. reported that the nutritional risk index (NRI), which is calculated using ALB, PBW, and normal body weight, is used to estimate the association between nutritional status and postoperative complications (16, 17). However, the NRI is difficult to assess in elderly patients because they do not remember their usual body weight often (18). Bouillanne et al. changed the actual weight to IBW in the NRI formula. They reported that the GNRI is a simple screening tool for predicting the nutrition-related risk of complications and mortality in elderly patients specifically (2).
There are tools for assessing nutritional status, such as BMI, sarcopenia, PNI, and subjective global assessment. These tools have been reported to be associated with cancer prognosis, but optimal cut-off values are still debated (19-22).
Additionally, subjective global assessment is based on many subjective factors that require expertise. For example, some studies have examined the usefulness of sarcopenia in relation to postoperative complications and cancer prognosis (23-25). Sarcopenia is a useful tool for evaluating nutritional status, but its measurement is complex.
GNRI is an objective and simple prediction tool. It is calculated using only ALB, height, and body weight, which are usually measured on admission for most patients. The iliopsoas muscle area (cm2) is used to assess sarcopenia. Shoji et al. reported a correlation between the iliopsoas muscle area at the third lumbar vertebral level and GNRI score (26).
Cereda et al. reported an association between GNRI and mid-upper arm muscle circumference, arm muscle area, handgrip strength, and handgrip strength/arm muscle area (27). Therefore, the GNRI may be a useful predicting tool for postoperative complications and prognosis, especially in patients in whom assessing sarcopenia is difficult or in institutions lacking measuring equipment.
The GNRI was proposed and has been widely used for nutritional assessment in elderly patients aged ≥65 years with heart failure (28), chronic renal failure on hemodialysis (29), and chronic obstructive pulmonary disease (30) and has been reported to be significantly correlated with ALB, prealbumin, body weight, and BMI (2).
The GNRI is a recently confirmed useful predictor of morbidity and mortality in patients with cancer (3). Li et al. reported an association between low GNRI and severe postoperative complications including liver failure and poor OS, in elderly patients with hepatocellular carcinoma (31). Kushiyama et al. reported that a GNRI<92 was a risk factor for postoperative complications in elderly patients with gastric cancer (32). Bo et al. reported that a GNRI≤98 was a potential indicator of poor survival in elderly patients with esophageal cancer treated with radiotherapy (33). Miyake et al. also reported that the GNRI could be a prognosis predictor in elderly patients with non-metastatic renal cell carcinoma, and that those with a GNRI≤98 had a significantly worse CSS than other patients (6). Sasaki et al. reported that patients with colorectal cancer aged ≥65 years after curative surgery having a preoperative GNRI ≤98 had more postoperative complications and a poorer prognosis (3). Iguchi et al. reported that patients with liver metastasis of colorectal cancer had poor prognosis in the group of GNRI ≤98 (34).
There are various studies on GNRI cut-off values. Some studies used the modified GNRI classification according to the complications (32, 35), survival (6, 33), and hospitalization (8), and others used the four-group classification suggested by Bouillanne et al. (2). There are no reports on NAC cases, but postoperative complications in patients with colorectal cancer have been reported to be associated with poor oncologic outcomes, even if they are mild or moderate (CD Grade II) (36).
However, owing to the small number of cases in this study, we considered CD Grade ≥III complications. This is because the number of cases in our study was small, and if we considered moderate complications (CD Grade II), more than half of the patients would be considered as having postoperative complications. Therefore, we determined a new cut-off from the ROC curve based on postoperative complications (CD Grade ≥III).
It has been reported that the GNRI may be a useful indicator not only for elderly patients. There was no significant difference in the preoperative GNRI between the two groups (over 65 or under 65 years), suggesting that the GNRI was not biased by age.
Low ALB levels have been shown to be correlated with poor cancer prognosis in many studies (37). ALB is a known indicator of nutritional status (38), and malnutrition impairs several functions, including immunity, gastrointestinal function, and wound healing (39). The absence of these functions increases the risk of infection and postoperative complications (40, 41), and immunosuppressive conditions lead to inadequate anti-tumor immunological reactions (42, 43).
Furthermore, it has been reported that ALB is influenced by inflammation (38), and systemic inflammation is associated with a poor cancer prognosis (44). BMI is also widely used in clinical practice as an indicator to assess nutritional status and has been reported to be associated with cancer prognosis (45). Thus, we suggest that the GNRI, which combines ALB and body weight, may predict nutrition-related risk better than ALB alone.
There are limitations to our study. First, this study was a retrospective study with a small sample size and few participating institutions, making it subject to several selection and information biases. Prospective multicenter studies should be performed in the future. Second, we adapted the GNRI to patients below 65 years of age in this study. In the future, we will accumulate cases and examine the usefulness of the GNRI in elderly patients. In addition, we will examine a new prediction formula for the GNRI according to age. Third, this study showed that the NAC course and regimen were not uniform, and the time intervals between NAC and surgery were not similar. We predict that patients with rectal cancer who undergo radical resection after NAC will increase, hence the need to unify our NAC courses and regimens.
To conclude, we identified GNRI as a significant marker of poor prognosis in patients with locally advanced colorectal cancer who underwent NAC followed by radical resection. We will continue to examine preoperative GNRI and prognosis after NAC in elderly patients.
Acknowledgements
The Authors are grateful to Aayaka Tojo and Aya Ito for helping with this study.
Footnotes
Authors’ Contributions
S.M., N.M., S.F., Y.D., and H.E. contributed to the conception and design of this study. S.M., N.M., and S.F. collected, analyzed, and interpreted the data. S.M., N.M., and S.F. wrote the manuscript. S.M., S.K., Y.S., T.H., T.O., H.T., M.U., and H.Y. followed up the clinical data. All Authors discussed the results and approved the manuscript.
Conflicts of Interest
The Authors declare no competing interests in relation to this study.
- Received May 18, 2022.
- Revision received June 13, 2022.
- Accepted June 14, 2022.
- Copyright © 2022 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.









