Leptin and adiponectin as new markers of undernutrition in cancer.

OBJECTIVES: To evaluate leptin and adiponectin as markers of undernutrition in cancer patients, and compare their performances with those of other biomarkers. DESIGN AND METHODS: This was a prospective and observational study of 132 patients with various types of cancer. Following the recommended professional criteria, we diagnosed undernutrition at the time of blood sampling for the biological analysis of leptin, adiponectin, paraoxonase (hydrolysis rate of three substrates: paraoxon (PON), phenylacetate (ARE) and thiolactone (LAC)), and the calculation of the Prognostic Inflammatory and Nutritional Index (PINI). Patients were monitored for one year to establish the mortality rate of the group. Relationships between biological variables and undernutrition were evaluated using univariate and multivariate logistic regression models. The Kaplan Meier method was used to analyse survival curves. Hazard ratios for death were calculated according to the quartiles of each biological variable. RESULTS: In the case of undernutrition, a decrease was observed in levels of leptin and in the lactonase activity (LAC) of paraoxonase, while adiponectin levels increased. Besides PINI, leptin was the only parameter that was independently related to undernutrition. While no relation was found between survival and leptin or adiponectin levels, evidence was found that PINI, LAC and ARE were associated with survival, even in multivariate analysis. CONCLUSIONS: Leptin and PINI are good markers of installed undernutrition, and PINI and ARE or LAC are reliable markers of the risk of death in patients suffering from cancer.

Paired measurement of serum amyloid A (SAA) and paraoxonase 1 (PON1) as useful markers in breast cancer recurrence.

OBJECTIVES: Paraoxonase 1 (PON1) and serum amyloid A (SAA) are carried by HDL. In case of inflammation, SAA and PON1 tend to change in opposite direction. In this study we determined if inflammation leads to altered PON1 activity using three different substrate hydrolysis rates, paraoxonase (PON), arylesterase (ARE) and lactonase (LAC) in breast cancer recurrence. DESIGN AND METHODS: 49 patients with a recurrence of breast cancer were analyzed for SAA, CRP, lipids, oxidized LDL, PON, ARE and LAC. Distribution of PON1 activities across the quartiles of CRP and SAA were compared by the Kruskal Wallis test. Non-parametric estimates of the survivor function were computed with Kaplan-Meier method. The association of SAA and ARE with short term death was assessed by logistic regression models. RESULTS: HDL and ARE decrease significantly across the quartiles of CRP. No significant differences were observed across SAA quartiles. The survival time was significantly related to the level of SAA (log rank: p<0.001) as well as the level of ARE (log rank: p=0.039). SAA and ARE were independently related to survival time below one year. CONCLUSIONS: PON1 does not seem to be directly affected by SAA, for any of the tested substrates, PON, ARE and LAC. The combined measurement of SAA and ARE could be a useful tool in this clinical situation, since they are independently related to short term death.

Acquired von Willebrand syndrome associated with monoclonal gammopathy: a single-center study of 36 patients.

In this single-center retrospective study, we evaluated the accuracy of laboratory tests in diagnosing acquired von Willebrand syndrome associated with lymphoproliferative disorders in 36 consecutive patients diagnosed at the University Hospital of Nantes, France. We also compared hemostatic treatments in the following groups: 21 patients with Waldenström macroglobulinemia (WM), 14 with monoclonal gammopathy of undetermined significance (MGUS) (10 with IgG-MGUS and 4 with IgM-MGUS), and 1 with IgA multiple myeloma (IgA-MM). The diagnosis was made in 18 (50%) patients during systematic screening, in 6 (17%) during active mild hemorrhage, and in 12 (33%) during an active, severe bleed. Of the laboratory tests studied, only closure times measured on the Platelet Function Analyzer (PFA)-100 device reliably diagnosed the hemostatic problem. There was no relationship between the factor VIII activity (FVIII:C) or von Willebrand factor activity (VWF:RCo) levels and the previous history of hemorrhage described by patients.We studied hemostatic treatment in most patients: IgG-MGUS patients responded well to high-dose intravenous immunoglobulin (IVIg) infusions (1 g/kg per d), although patients with IgM-MGUS did not. Desmopressin infusions were effective in 3 patients with IgG-MGUS and 2 patients with IgM-MGUS when the baseline values were above 10 IU/dL, but levels soon returned to the baseline. The 7 WM patients had a good response to desmopressin. These results confirm the efficacy of IVIg in IgG-MGUS patients and the prominent role of closure time in the diagnosis of acquired von Willebrand syndrome.

Evaluation of an automated von Willebrand factor activity assay in von Willebrand disease.

We evaluated the use of the turbidimetric HemosIL von Willebrand Factor (VWF) Activity assay (VWF:Act) on the STA-R automated coagulometer (Stago, Asnières, France) for the diagnosis of von Willebrand disease (VWD). For this, we prospectively screened 268 patients. As a second part, we retrospectively assayed 111 patients with well-defined VWD subtype. In the first prospective study, we demonstrate that in most cases of VWD, VWF ristocetin cofactor activity (VWF:RCo) and VWF:Act are highly correlated but that they both cannot be considered a good screening assay when used alone, since they could miss about 25% of VWF abnormalities. However, the association of VWF:Act analysis and the Platelet Function Analyzer-100 (PFA-100) test constitutes an excellent screening strategy. In our second retrospective study concerning VWD subtypes, VWF:RCo and VWF:Act were well correlated but could be very discrepant, especially for some cases of type 2M VWD. We consider that VWF:RCo remains the "reference assay" for VWD subtype classification.