Mean Platelet Volume to Lymphocyte Ratio: A New Biomarker Predicting Response in Patients with Solid Tumors Treated with Nivolumab.

Introduction: Although immune checkpoint inhibitors (ICIs) are widely used in cancer treatment, identifying factors that predict treatment response remains a challenge in clinical practice. There is a need for biomarkers to identify patients who may not benefit from these treatments. It is crucial to identify a simple and cost-effective biomarker that can be easily incorporated into clinical practice. This study aims to investigate the mean platelet volume to lymphocyte ratio (MPVLR), as measured by a hemogram test, and median overall survival (mOS) in patients with cancer treated with nivolumab.

Methods: A total of 131 adult patients with metastatic cancer, including malignant melanoma (MM), renal cell carcinoma (RCC), non-small cell lung cancer (NSCLC), and head and neck cancer (HNC), were included in this study. Baseline demographics, ECOG (Eastern Cooperative Oncology Group) performance status, tumor type, and blood count parameters were recorded. Univariate and multivariate analyses were conducted to evaluate potential risk factors.

Results: The median age of the patients was 59.87 ± 11.97 years, and the median follow-up period was 20.20 months (IQR, 12.80-27.60). RCC (43.5%) and MM (25.9%) were the most common diagnoses. Patients with ECOG scores of 0-1 had a longer mOS than those with scores of 2-3 (mOS: 20.60 months [95% CI, 14.94-25.29] vs. 5.24 months [95% CI, 0-16.42], p < 0.001). Additionally, patients with lactate dehydrogenase (LDH) levels within the normal range had a longer mOS than those with high LDH levels (mOS: 24.54 months [95% CI, 14.13-34.96] vs. 13.10 months [95% CI, 4.49-21.72], p = 0.038). Patients with low MPVLR also had a longer mOS than those with high MPVLR (mOS: 33.70 months [95% CI, 25.99-41.42] vs. 11.07 months [95% CI, 6.89-15.24], p < 0.001). In the multivariate Cox regression analysis, high MPVLR, ECOG score of 2-3, and high LDH level were associated with shorter mOS (p < 0.001, p = 0.001, and p = 0.046, respectively).

Conclusion: This study demonstrates that MPVLR could serve as a novel biomarker for predicting response to nivolumab treatment. Incorporating MPVLR into clinical practice may aid in identifying patients who are less likely to benefit from the treatment.