Low High-Density Lipoprotein Cholesterol (HDL) Is a Significant Poor Prognostic Factor in Malignant Lymphoma

Objective: HDL is reportedly an independent prognostic factor in some malignant lymphoma (ML). We retrospectively analyzed the correlation between the prognosis of ML, including both Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL) and dyslipidemia in patient cases from our experience.

Methods: Analyzed patients were; ML patients admitted to our hospital between April, 2009 and March, 2015. We excluded the patients who did not receive any treatments or were observed for less than two years after starting treatment. Dyslipidemia was defined as blood serum HDL, low-density lipoprotein cholesterol (LDL), and Triglyceride (TG) levels <40 mg/dL, >140 mg/dL, and >150 mg/dL, respectively. We performed statistically univariate and multivariate analyses.

Results: Analyzed patients were: total 221 patients, median age of 68 (20-89), male 130 and female 91, B cell NHL 183, T/NK cell NHL 29, HL 8, and others 1, age under 60 62 and above 60 159, Performance Status (PS) 0-1 172 and 2-4 49, Ann Arbor classification I-II 48 and III-IV 173. 57 patients were deceased and 164 were alive at the analysis. The low HDL group (97 cases) showed a significantly shorter survival than high HDL group (124 cases; p = 0.0001), while there were no correlations between either high TG (38 cases) or high LDL (22 cases) and survival. In multivariate analysis, PS 2 or more, and low HDL were extracted as significant adverse prognostic factors.

Discussion: The mechanisms of this correlation between survival of ML and low HDL level are still unclear. It is reported that inflammatory cytokines produced by ML cells may induce dyslipidemia. Because scavenger receptor-B1 with high affinity for HDL is highly expressed on ML cell-surface, it is possible that low HDL is correlated to the ML tumor-volume or fast tumor turnover. Since expression of scavenger receptor-B1 is low on normal lymphocytes, consumption of HDL may occur in ML. In this point there have been several attempts for treatment using HDL, such as an administration of HDL nanoparticle as a drug delivery vehicle in animal lymphoma-models. Thus, we will further investigate this correlation between HDL and ML with more patients and also study the mechanism.