The relationship between adiposity and gleason score in men with localized prostate cancer

Relationship of self-reported body size and shape with risk for prostate cancer: A UK case-control study

INTRODUCTION

Previous evidence has suggested a relationship between male self-reported body size and the risk of developing prostate cancer. In this UK-wide case-control study, we have explored the possible association of prostate cancer risk with male self-reported body size. We also investigated body shape as a surrogate marker for fat deposition around the body. As obesity and excessive adiposity have been linked with increased risk for developing a number of different cancers, further investigation of self-reported body size and shape and their potential relationship with prostate cancer was considered to be appropriate.

OBJECTIVE

The study objective was to investigate whether underlying associations exist between prostate cancer risk and male self-reported body size and shape.

METHODS

Data were collected from a large case-control study of men (1928 cases and 2043 controls) using self-administered questionnaires. Data from self-reported pictograms of perceived body size relating to three decades of life (20's, 30's and 40's) were recorded and analysed, including the pattern of change. The associations of self-identified body shape with prostate cancer risk were also explored.

RESULTS

Self-reported body size for men in their 20's, 30's and 40's did not appear to be associated with prostate cancer risk. More than half of the subjects reported an increase in self-reported body size throughout these three decades of life. Furthermore, no association was observed between self-reported body size changes and prostate cancer risk. Using 'symmetrical' body shape as a reference group, subjects with an 'apple' shape showed a significant 27% reduction in risk (Odds ratio = 0.73, 95% C.I. 0.57-0.92).

CONCLUSIONS

Change in self-reported body size throughout early to mid-adulthood in males is not a significant risk factor for the development of prostate cancer. Body shape indicative of body fat distribution suggested that an 'apple' body shape was protective and inversely associated with prostate cancer risk when compared with 'symmetrical' shape. Further studies which investigate prostate cancer risk and possible relationships with genetic factors known to influence body shape may shed further light on any underlying associations.

Obesity is not associated with aggressive pathologic features or biochemical recurrence after radical prostatectomy

OBJECTIVE

To determine whether obesity is associated with adverse pathologic characteristics, positive surgical margins, greater biochemical recurrence rates, and interval to death after primary treatment with radical prostatectomy (RP).

MATERIALS AND METHODS

A 12-year, retrospective, single-institution analysis of patients treated with RP was performed. Patients were categorized by their body mass index (BMI) as normal weight (n = 533), overweight (n = 1342), obese (n = 603), and morbidly obese (n = 22). The associations among the BMI, clinicopathologic characteristics, and biochemical recurrence rates were assessed.

RESULTS

After adjusting for multiple clinical preoperative characteristics, the BMI category was not associated with positive surgical margins (P = .66), organ-confined disease (P = .10), Gleason score (P = .22), extracapsular extension (P = .09), seminal vesicle invasion (P = .15), percentage of cancer in the prostate gland (P = .67), largest tumor nodule (P = .13), or lymph node metastasis (P = .39). Gleason score 4+3 (P <.001), Gleason score 9 and 10 (P <.001), and an increasing prostate-specific antigen level (P <.001) were associated with biochemical recurrence. At a mean overall follow-up of 55.6 months, 276 patients (11.0%) had developed biochemical recurrence (normal weight 11.3%, overweight 10.5%, obese 12.3%, and morbid obesity 4.5%). After multivariate adjustment for age, ethnicity, risk group, clinical stage, Gleason score, preoperative prostate-specific antigen level, and year of surgery, no association was found between the BMI and biochemical recurrence (P = .87).

CONCLUSION

In men undergoing RP for clinically localized prostate adenocarcinoma, obesity was not associated with adverse pathologic features, positive surgical margins, or biochemical recurrence. These data provide evidence that obese men undergoing RP are not more likely to have aggressive prostate cancer.