Change of the Neutrophil-to-Lymphocyte Ratio during Treatment: A Potential Prognostic Biomarker in Metastatic Prostate Cancer Treated with Radium-223 Dichloride

SIMPLE SUMMARY: We analyzed the influence of the neutrophil to lymphocyte ratio (NLR) and its change during therapy as a potential prognostic marker in metastatic prostate cancer patients treated with (223)Radium ((223)Ra) and patients treated with docetaxel. We found that a low NLR at baseline as well as at 12 weeks of treatment was associated with a better overall survival only in patients treated with (223)Ra but not in patients treated with Docetaxel. Patients with a baseline NLR ≤ 5 that remained low (NLR ≤ 5) at 12 weeks of treatment had significantly longer median survivals compared to patients whose NLR was low (<5) at baseline and that converted at 12 weeks to >5. The prognostic value of NLR at baseline and 12 weeks will need to be validated in larger prospective cohorts. ABSTRACT: The neutrophil to lymphocyte ratio (NLR) at baseline has been shown to have prognostic value in metastatic prostate cancer. Little is known about the importance of a change in the NLR during treatment in patients treated with Radium-223 ((223)Ra). We investigated the prognostic value of the NLR at baseline and during therapy in patients with metastatic prostate cancer treated with (223)Ra and also in patients treated with Docetaxel. We reviewed all patients treated with (223)Ra in our center and randomly chosen patients treated with Docetaxel. Patients were stratified according to NLR ≤ 5 and >5 at baseline and at 12 weeks of therapy. The relationship between NLR measured at baseline and at 12 weeks and overall survival (OS) were evaluated. A total of 149 patients treated with (223)Ra and 170 with Docetaxel were evaluated. For patients treated with (223)Ra, overall survival was significantly better in patients that had both an NLR ≤ 5 at baseline and at 12 weeks. No such effect of NLR was found in patients treated with Docetaxel. In the present study, NLR at baseline and after 12 weeks of therapy was found to be prognostic factor in patients treated with (223)Ra but not in those treated with Docetaxel.