Prognostic value of quantitative immune alterations in melanoma patients

Abstract

• Purpose: The immune response is altered in patients with neoplasms. Immunosuppression has important consequences in patients with melanoma. The aim of this study was to assess quantitative immune alterations in melanoma patients.. • Material and methods: We obtained a peripheral blood sample in EDTA from 86 melanoma patients (63 of them disease-free and 23 with distant disease). Total leukocytes and lymphocytes, B lymphocytes (CD19), types CD3, CD4, CD8 lymphocytes, and NK lymphocytes (CD56) were counted by determining the surface markers by flow cytometry, using a Coulter Epics Elite (Coulter Corp.). IgA, IgG, IgE and IgM were assayed by nephelometric methods employing a Hyland PDQ laser nephelometer. • Results: We found significant differences between disease-free patients and those with active disease with regard to lymphocytes total count (median: 2251.57 vs. 1783.04/mm 3 , p=0.010), NK lymphocytes (CD56) (149.54 vs. 115.2/mm 3 , p=0.016), and IgA levels (241.59 vs. 300.55 mg/dl, p=0.044), when taken as continuous variables. When considering each parameter as a discontinuous variable, only changes in absolute lymphocyte count retained an statistical difference depending on the presence or absence of active disease, 73.9% of the patients with active metastatic disease having a lymphocyte count below 2000 cells/mm 3 versus only 36.5% of the disease-free patients (c2 Pearson=9.476, df=1, p=0.002). The median survival for the 46 patients with absolute lymphocyte count above 2000 cells/mm 3 was 965 days (DF=65.03, IC 95%=792.72-1090.30) versus 441 days (DF=75.61, IC 95%=292.81-589.19) for the 40 patients with absolute lymphocyte count below 2000 cells/mm3 (log rank=4.54, df=1, p=0.0331). • Conclusions: There are significant differences in some lymphocyte populations and IgA levels between patients with metastases and disease-free patients. Melanoma patients with absolute lymphocyte levels above 2000 cells/mm3 have a longer survival than those with a lymphocyte count below 2000 cells/mm 3 .