Should the cut-off values of the lymphocyte to monocyte ratio for prediction of prognosis in diffuse large B-cell...

A recent study suggested a prognostic role for the peripheral blood absolute lymphocyte/monocyte ratio (LMR) at diagnosis of diffuse large B-cell lymphoma (DLBCL). Here, we investigated the significance of LMR in DLBCL patients in relation to advanced age.

We examined the prognostic impact of LMR in 603 DLBCL treated with rituximab plus CHOP, using the receiver operating characteristic curve analysis for optimal cut-off values, and performed a subgroup analysis according to age.

In elderly groups (age ≥ 70), absolute monocyte count was significantly increased, whereas LMR was significantly decreased compared to younger groups. Patients under 70 yr of age with LMR < 3.04 had significantly lower overall survival (OS) and progression-free survival (PFS) compared to those with LMR ≥ 3.04 (P < 0.001 for both). However, in elderly patients (age ≥ 70), there was no significant difference in OS between patients' LMR levels using the 3.04 cut-off value (P = 0.059). Therefore, a new LMR cut-off value of 2.36 was selected in elderly patients, having observed that elderly patients with LMR < 2.36 had significantly lower OS compared to those with LMR ≥ 2.36 (P = 0.021). In multivariate analysis, LMR remained a significant prognostic factor for OS (P = 0.004) or PFS (P < 0.001).

We suggest the use of a different cut-off value of LMR in elderly patients to distinguish high-risk from low-risk groups.