Significance of Neutrophil-to-Lymphocyte Ratio, Platelet-to-Lymphocyte Ratio and Monocyte-to-Lymphocyte Ratio in the Prognosis of Newly Diagnosed Multiple Myeloma Patients

Background

Multiple myeloma is a cancer of the plasma cells, characterized by abnormal proliferation in the bone marrow. In 2023 about 12,590 deaths are expected to occur secondary to the disease. It is important to identify the predictors of disease progression for prognostication.Tumor microenvironment influences the growth of malignant plasma cells. Neutrophilia can enhance tumor growth, angiogenesis and provide a favorable matrix for metastasis. Lymphopenia is also suggestive of disease progression. Hence, an increased neutrophil-to-lymphocyte ratio (NLR) has been linked with a poor prognosis in many cancers. Monocytes are thought to be recruited by tumor cells for suppressing the immune cells and aiding in prolonged survival. In patients with multiple myeloma, a low platelet count is linked to a worse prognosis since a greater marrow myeloma burden leads to inhibition of thrombopoiesis.Hence, a low platelet-to-lymphocyte ratio (PLR) and high monocyte-to-lymphocyte ratio (MLR) are linked with worse prognosis.The aim of our study was to investigate the role of NLR, PLR and MLR in the prognosis of our patients.

Methods

This is a retrospective study that analyzed patients diagnosed with Multiple Myeloma from 2012 to 2022 at Saint Vincent Cancer Center, Worcester, Massachusetts. We performed a chart review and collected demographics including age at the time of diagnosis, gender, BMI, race. Additionally, we also collected data such as multiple myeloma type, R-ISS staging, complete blood count (cbc), chemotherapy used, auto stem cell transplant, 5-year survival. NLR, PLR and MLR were calculated based on pre-treatment cbc. Based on literature review, cutoffs for High NLR (≥2), Low NLR (<2), High PLR (≥120.00), low PLR (<120.00) and high MLR (≥0.27), and low MLR (<0.27) were made. SPSS was used for analysis of the data. A logistic regression was used to calculate the Odd's ratio (OR). A p value less than equal to 0.05 was considered significant.

Results

The total number of patients analyzed were 97. 47.4% (n=46) were females and 52.6% (n=51) were males. Mean age at diagnosis was 69.3 years. Mean BMI was 30.16 kg/m ². 35.1% (n=34) of the patients had IgG subtype. 36.1% (n=35) of our study population belonged to R-ISS stage 2. 38.1% (n=37) of the patients were treated with lenalidomide, bortezomib, dexamethasone combination. Mean NLR was 3.4, mean PLR was 166.949 and mean MLR was 0.46. 66% (n=64) of the patients belonged to the high NLR group, 61.9% (n=60) to the high PLR group and 64.9% (n=63) to the high MLR group. Out of 97 patients, 56.7% (n=55) were alive at 5 years. High NLR (≥2) was associated with lower odds of 5-year survival with a p value of 0.037 and a 95% confidence interval (0.095-0.931). High MLR (≥0.27) was associated with lower odds of 5-year survival with a p value of 0.042 and a 95% confidence interval (0.124-0.962). PLR did not correlate with 5-year survival and was not statistically significant (p value of 0.157).

Conclusions

Based on our study, a high NLR (≥2) and high MLR (≥0.27) were associated with lower odds of 5-year survival. Hence NLR and MLR are independent prognostic factors in newly diagnosed multiple myeloma patients which can be economical and effective methods for early evaluation of patient prognosis.