Diabetic men undergoing radical prostatectomy (RP) for prostate cancer are more likely to develop castration-resistant and metastatic disease if they have worse glycemic control, according to the authors of a new study.

Stephen J. Freedland, MD, of Cedars-Sinai Medical Center in Los Angeles, and colleagues reviewed the medical records of 1409 patients with diabetes undergoing RP during 2000 to 2017 at 8 Veterans Affairs hospitals. Of these, 699, 631, and 79 patients had a hemoglobin A1c (HbA1c) value of less than 6.5%, 6.5% to 7.9%, and 8.0% or more, respectively, in the year prior to surgery. Those with the highest HbA1c values tended to be younger and black. The median follow-up duration following RP was 6.8 years.

On multivariable analysis, as a continuous variable, higher HbA1c was significantly associated with a 27% and 21% increased risk of castration-resistant disease and metastasis, respectively, Dr Freedland’s team reported in Cancer. Models were adjusted for biopsy grade group and PSA only because of limitations of few events. No association was found between HbA1c and biochemical disease recurrence, in line with previous studies.

“Although the current study data suggest there may be an association between serum glucose levels and PCa progression, future studies are needed to understand whether insulin or hyperglycemia is of greater clinical significance,” Dr Freedland and his colleagues concluded. Only a small proportion of men had HbA1c levels exceeding 8%, so the researchers encouraged larger studies with longer follow-up beyond 7 years.

Reference

Nik-Ahd F, Howard LE, Eisenberg AT, et al. Poorly controlled diabetes increases the risk of metastases and castration-resistant prostate cancer in men undergoing radical prostatectomy: Results From the SEARCH database. Canc. doi:10.1002/cncr.32141