The ratio of the absolute lymphocyte count to the absolute monocyte count is associated with prognosis in Hodgkin's lymphoma: correlation with tumor-associated macrophages

Abstract

Background: Although most patients with classical Hodgkin's lymphoma (cHL) have a long survival duration, the current risk stratification is imperfect. A recent study suggested a prognostic role for the peripheral blood absolute lymphocyte count/absolute monocyte count (ALC/AMC) ratio at diagnosis in cHL. It is intriguing to investigate the significance of the ALC/AMC ratio in relation to tumor-associated macrophages (TAMs), yet another prognostic factor for cHL.

Methods: We examined the prognostic impact of the ALC, AMC, and ALC/AMC ratio in 312 cHL patients (median age, 37 years) using receiver operating characteristic curve analysis for optimal cutoff values, and compared these with TAM content.

Results: The median follow-up was 65 months (range, 0.1-245 months). On univariate analysis, a low ALC/AMC ratio (<2.9) was correlated with a poorer overall survival (OS) outcome. A subgroup analysis of patients with limited-stage disease showed that the ALC/AMC ratio was significantly correlated with the OS time. Multivariate analysis showed the ALC/AMC ratio to be an independent prognostic factor for OS outcome. A Spearman correlation test of TAM content showed a negative correlation with the ALC/AMC ratio and a positive correlation with the peripheral blood macrophage percentage.

Conclusions: This study suggests that the ALC/AMC ratio may be a simple, inexpensive, and independent prognostic factor for OS outcome in patients with cHL and may have a role in the stratification of cHL patients in addition to the International Prognostic Score and TAM content.

Conflict of interest statement

Disclosures: The authors indicated no financial relationships.

Figures

Figure 1.

Receiver operating characteristic curve (ROC) and area under the curve (AUC) for the ALC (A), AMC (B), and ALC/AMC ratio (C) at diagnosis. Abbreviations: ALC, absolute lymphocyte count; AMC, absolute monocyte count; CI, confidence interval.

Figure 2.

Comparison of the survival using the cutoff value of 2.9 for ALC/AMC ratio at diagnosis. (A): Overall survival and (B) even-free survival. Abbreviations: ALC, absolute lymphocyte count; AMC, absolute monocyte count.

Figure 3.

Comparison of ALC/AMC ratio and International Prognostic Score in limited-stage disease (A, C) and advanced-stage disease (B, D). Abbreviations: ALC, absolute lymphocyte count; AMC, absolute monocyte count.

Figure 4.

Comparison of the survival using the cutoff value of 2.9 for ALC/AMC ration at diagnosis in patients with the nodular sclerosis subtype (A) and mixed cellularity subtype (B) of Hodgkin's lymphoma. Abbreviations: ALC, absolute lymphocyte count; AMC, absolute monocyte count.

Figure 5.

Spearman correlation between peripheral monocytes (%) and number of CD68+ cells (p = .019) (A), peripheral monocytes (%) and number of CD163+ cells (p < .001) (B), and the ALC/AMC ratio and number of CD68+ cells (p = .006) (C). Abbreviations: ALC, absolute lymphocyte count; AMC, absolute monocyte count.