Relationship between serum adiponectin and prostate cancer grade

BACKGROUND. Obesity is associated with prostate cancer (PCA) grade, but the mechanism behind this relationship is not understood. Adiponectin is an adipokine that has been linked with the development of hormonally sensitive carcinomas, including prostate cancer. We evaluated the relationship between serum adiponectin and Gleason score (GS) in a prospective series of patients seen in a single institution. METHODS. Localized PCA patients evaluated at Dana-Farber Cancer Institute between 2001 and 2005 who enrolled in a prospective serum banking protocol were eligible for this study. Patients with prior hormonal therapy and/or metastatic disease were excluded. High-grade disease was defined as biopsy or radical prostatectomy (RP) GS of 7 or higher. Logistic regression models were used to assess the relationship between high-grade disease and adiponectin levels while adjusting for other potential prognostic variables. RESULTS. There were 539 patients included in this study, of whom 199 had undergone RP. Median age was 60 years. Median PSA was 5.1 ng/dl. Biopsy GS of 7 or higher was seen in 46.9% of patients. For biopsy GS, higher PSA, older age, and higher BMI were significantly associated with increased odds of GS 7 or higher, but adiponectin was not. In men undergoing RP, there was a significant inverse relationship between pathologic GS and adiponectin dichotomized at the median, due to a significantly higher rate of upgrading in patients with lower adiponectin (P = 0.014). CONCLUSIONS. Although there was no association between biopsy GS and adiponectin, in patients who had undergone RP, lower adiponectin was independently associated with high-grade prostate cancer.