Circulating CD8+ lymphocytes, white blood cells, and survival in patients with mycosis fungoides.

Background: There is a need for reliable, easily measurable laboratory markers that may help dermatologists to predict the course of mycosis fungoides (MF) when they first evaluate their patients.

Objectives: Our objective was to identify clinical, haematological or immunological parameters as predictors of mortality in patients with MF.

Methods: We conducted a retrospective study on a prevalent cohort of 124 patients with MF hospitalized at IDI-IRCCS, Rome, Italy, from 1983 to 2001. We calculated the proportion of patients surviving (Kaplan-Meier product-limit estimates) 5 and 10 years after first hospital admission, and hazard ratios (HR) from the Cox proportional hazards model.

Results: Patients' survival was linked to age and staging (lower survival in older patients and in patients with staging IIB-IV). Higher numbers of white blood cells (WBC) and neutrophils, lower numbers of CD8+ lymphocytes, low haematocrit and lower levels of albumin were significantly associated with a lower survival probability. When simultaneously accounting for age and staging, CD8+ [HR = 3.02, 95% confidence interval (CI) 1.01-9.07 for CD8+ < 250 vs. > or = 600 cells microL(-1)] and WBC (HR = 2.59, 95% CI 0.96-6.96 for WBC > or = 9000 vs. < 6000 cells microL(-1)) were associated with survival. In addition, we observed an exceedingly high risk of death (HR = 12.40, 95% CI 3.11-49.43) for patients with a combination of WBC > or = 9000 and CD8+ < 600 cells microL(-1) vs. WBC < 9000 and CD8+ > or = 600 cells microL(-1)).

Conclusions: The measurement of CD8+ cells and WBC in MF seems to be a promising criterion to predict survival, and possibly to support treatment decisions and inclusion of patients in randomized controlled trials.