Association of Obesity with Prostate Cancer at Time of Biopsy: A MultiCentre 10-Year Retrospective Study

Abstract

Background and Aim: The incidence of Prostate cancer (PCa) is on the rise in Cameroon, making it the most commonly diagnosed cancer amongst men. Factors, such as obesity, smoking, and the consumption of high fat diet have been reported to play a role in the aetiology and progression of cancers in general. However, the exact relationship between obesity and prostate cancer in Africans is still poorly described. The present study aimed to evaluate the association between obesity as measured by the body mass index (BMI) and high-grade prostate cancer in Cameroonians. Methods: This was a retrospective analyses of the clinical records of 300 consecutive men who underwent transrectal ultrasound-guided core needle prostate biopsy between January 2010 and January 2020. Patients were grouped as obese (BMI ≥30kg/m²) and non-obese (BMI <30kg/m²) and binary logistic regression modelling was used to compare the association between obesity and patient characteristics, such as age, digital rectal examination (DRE) findings, prostate specific antigen (PSA) level, prostate volume, PSA density, and Gleason score (GS). Results: The mean age at diagnosis of PCa was 65.46 ± 8.54 years (Range: 34-89 years), the mean BMI was 28.93 ± 4.57 kg/m² (Range: 18.35-42.37 kg/m²), and the median total PSA level was 44.2 ng/ml. In total, 142 men (47.3%) were obese and biopsies detected high-grade prostate cancer in 160 men (63.3%). Obese men were significantly younger and had a higher risk (OR= 2.74, p <0.001) of having high-grade PCa compared to nonobese men. Furthermore, 94 obese men (58.75%) had high-grade PCa. Obese men had higher age-adjusted PSA densities (P<0.001), while there was no statistical difference in DRE findings (OR= 1.06, p= 0.225). Conclusion: This study demonstrated that obesity is associated with a higher risk of high-grade prostate cancer. This risk is more pronounced among younger patients and DRE findings are not influenced by BMI.