Systematic review and meta-analysis of nutritional indices in breast cancer prognosis
This is a systematic review and meta-analysis of 13,120 individuals with breast cancer, examining the prognostic value of the prognostic nutritional index (PNI) and controlling nutritional status (CONUT) score. The authors synthesized evidence on overall survival (OS), disease-free survival (DFS), and pathological complete response (pCR).
For PNI, higher values were linked with improved OS (HR = 0.49; 95% CI 0.39-0.61; P < 0.00001) and longer DFS (HR = 0.69; 95% CI 0.58-0.81; P < 0.00001). The association with pCR was inconclusive (OR = 1.57; 95% CI 1.00-2.47; P = 0.05). For CONUT, higher scores corresponded to poorer OS (HR = 1.77; 95% CI 1.29-2.44; P = 0.0005) and shorter DFS (HR = 2.08; 95% CI 1.75-2.47; P < 0.00001).
The authors acknowledge key limitations. Evidence for an association between PNI and pCR was inconclusive. Results were sensitive to individual studies. Prediction intervals for PNI and OS, PNI and DFS, PNI and pCR, and CONUT and OS all crossed the null value, indicating substantial between-study variability.
Practice relevance is restrained; the authors suggest PNI and CONUT may be considered candidate prognostic indicators in breast cancer. No safety data were reported, and the certainty of evidence was not formally assessed.