Obesity, Risk of Biochemical Recurrence, and PSADT after Radical Prostatectomy: Results from the SEARCH Database

To examine the association between body mass index (BMI) and aggressive biochemical recurrence (BCR) using the Shared Equal Access Regional Cancer Hospital (SEARCH) database.

We identified 4,123 men with complete data treated by radical prostatectomy between 1988 and 2015. We tested the association between BMI and BCR using Cox models and among men with BCR, PSA doubling time (PSADT) was compared across BMI categories using linear regression. Models were adjusted for age, race, PSA, biopsy Gleason score, clinical stage, year, and surgical center.

Overall, 922 men (22%) were normal weight (BMI <25 kg/m2), 1863 (45%) were overweight (BMI 25-29.9), 968 (24%) were obese (BMI 30-34.9), and 370 (9%) were moderately or severely obese (BMI ≥35). After adjustment for multiple clinical characteristics, higher BMI was significantly associated with higher risk of BCR (p=0.008). Among men with a BCR, men in the four BMI categories had similar multivariable adjusted PSADT values (increasing BMI categories: 20.9 vs. 21.3 vs. 21.0 vs. 14.9 months, p=0.48).

While we confirmed higher BMI was associated with BCR, we found no link between BMI and PSADT at the time of recurrence. Our data suggest obese men do not have more aggressive recurrences. Future studies are needed to test whether obesity predicts response to salvage therapies. This article is protected by copyright. All rights reserved.

Freedland SJ, Branche BL, Howard LE, Hamilton RJ, Aronson WJ, Terris MK, Cooperberg MR, Amling CL, Kane CJ; SEARCH Database Study Group. Obesity, risk of biochemical recurrence, and prostate-specific antigen doubling time after radical prostatectomy: results from the SEARCH database. BJU Int. 2019 Jul;124(1):69-75. doi: 10.1111/bju.14594. Epub 2018 Nov 16. PMID: 30347135; PMCID: PMC6476692.