Geriatric nutritional risk index after neoadjuvant chemoradiotherapy and survival in older patients with advanced rectal cancer.

Purpose: To investigate the clinical impact of malnutrition on the survival of older patients with advanced rectal cancer who underwent neoadjuvant chemoradiotherapy.

Methods: We investigated the clinical significance of the geriatric nutritional risk index (GNRI) in 237 patients aged over 60 years with clinical stage II/III rectal adenocarcinoma who were treated with neoadjuvant long-course chemoradiotherapy or total neoadjuvant therapy followed by radical resection from 2004 to 2017. Pre-treatment and post-treatment GNRI were evaluated, with patients split into low (< 98) and high (≥ 98) GNRI groups. The prognostic impact of pre-treatment and post-treatment GNRI levels on overall survival (OS), post-recurrence survival (PRS), and disease-free survival (DFS) was evaluated using univariate and multivariate analyses.

Results: Fifty-seven patients (24.1%) before neoadjuvant treatment and 94 patients (39.7%) after neoadjuvant treatment were categorized with low GNRI. Pre-treatment GNRI levels were not associated with OS (p = 0.80) or DFS (p = 0.70). Patients in the post-treatment low GNRI group had significantly poorer OS than those in the post-treatment high GNRI group (p = 0.0005). The multivariate analysis showed that post-treatment low GNRI levels were independently associated with poorer OS (hazard ratio, 3.06; 95% confidence interval, 1.55-6.05; p = 0.001). Although post-treatment GNRI levels were not associated with DFS (p = 0.24), among the 50 patients with recurrence, post-treatment low GNRI levels were associated with poorer PRS (p = 0.02).

Conclusion: Post-treatment GNRI is a promising nutritional score associated with OS and PRS in patients over 60 years with advanced rectal cancer treated with neoadjuvant chemoradiotherapy.