Is periprostatic adipose tissue associated with aggressive tumor biology in prostate cancer?

Abstract

The prevalence of overweight and obesity and their health-related problems have been increasing. Obesity is increasingly recognized as a risk factor in different types of cancer in humans. The mechanisms supporting the link between obesity and cancer development have not been fully understood. Leptin, a circulating cytokine produced by adipocytes, may influence prostate cancer (PCa) progression in different ways. Body mass index seems to be an unreliable predictor for the development of PCa, but its influence on progression and poor oncological outcomes seems to be clear. Given the fact that abdominal fat is the most metabolically active fat, with different metabolic and paracrine effects, related anthropometric measurements may lead to a better estimation of PCa risk. Metabolically active periprostatic abdominal fat may also play an important role in releasing cytokines and growth factors that may promote tumor cell proliferation or even create a favorable environment for aggressive tumor biology. Different imaging measurements, e.g., periprostatic adipose tissue (PPAT) thickness, may be significant predictors of PCa. Several genes in the PPAT of obese men have been identified to contribute to chronic immuno-inflammatory responses which eventually lead to cell cycle alteration with oncological potential. In vitro studies showed the importance of PCa and its interaction with its microenvironment particularly in patients with aggressive PCa. Different types of cytokines, such as interleukin-6, may promote a tumorigenic microenvironment. This article endeavors to review the current literature on the association of PPAT with aggressive tumor biology in PCa.

Keywords: Prostate cancer, Obesity, Periprostatic fat

Core tip: Globally, prostate cancer (PCa) is highly prevalent. Although the prevalence of PCa is similar across different populations, major differences in PCa incidence and mortality are seen worldwide. A contribution of environmental factors, such as obesity, may play an important role. Most studies used body mass index as a factor of obesity. However, only visceral fat is metabolically active. In a study by van Roermund et al, periprostatic fat measured on a computed tomography scan correlated with tumor aggressiveness. In this review, we aim to give more insight into the relationship between periprostatic fat and Pca aggressiveness by reviewing the recent literature.