Purpose: The inflammatory status of patients with cancer appears to affect cancer progression and patient prognosis. We examined the characteristics of cancer-associated systemic and local inflammation and its impact on the overall survival (OS) of patients with locally advanced rectal cancer (LARC) who received neoadjuvant radiotherapy (nRT).
Patients and methods: Seventy-six consecutive LARC patients who received nRT from February 2012 to September 2015 were retrospectively analyzed. The peripheral neutrophil-to-lymphocyte ratio (NLR) was determined at diagnosis, and the CD8+ T-cell count was determined from surgical specimens. Factors associated with OS were identified by univariate and multivariate Cox regression.
Results: The median follow-up time was 23.0 months (range: 2–59), and the overall 5-year OS rate was 68.6% (95% CI =46.06–91.14). Patients with a high NLR (≥2.0) and a low CD8+ T-cell count (<9%) had a significantly worse 5-year OS than those with a low NLR and a high CD8+ T-cell count (P =0.005). NLR was also associated with lymphovascular invasion (P =0.014) and T stage (P =0.047), and the CD8+ T-cell count was associated with mucinous adenocarcinoma (P =0.005) and T stage (P =0.049). An NLR <2.0 was associated with pathological complete regression after nRT (P =0.039). Multivariate Cox regression indicated that NLR (P =0.025), CD8+ T-cell count (P =0.018), age (P =0.020), lymphovascular invasion (P =0.038), and T stage (P =0.011) were independently associated with OS.
Conclusion: A high NLR and a low CD8+ T-cell count were significantly associated with poor survival in our population of patients with LARC. Measurement of markers of systemic and local inflammation might help to predict the prognosis of patients with LARC after nRT.
Keywords: inflammation, NLR, CD8+ T-cell count, prognosis, rectal cancer, neoadjuvant radiotherapy