Chapter 113 Prostate

Question 1

What is the pathophysiology behind BPH

Answer 1

Prostate gland begins to enlarge and function in the dog with onset of puberty and continues to undergo progressive androgen-mediated enlargement throughout life as the consequence of BPH changes
Circulating testosterone is metabolized by 5α-reductase to 5α-dihydrotestosterone in the prostate, where, through interaction with a receptor protein, it regulates gene expression in the nuclei to control prostatic growth.

Question 2

What percentage of beagles were affected by BPH at 2 year, 4-5 years, and > 7 years of age

Answer 2

16% at 2 years
50% at 4-5 years
70% over 7 years

Question 3

What are the two histologically distinct types of BPH and when are they more likely to occur

Answer 3

Glandular in dogs < 5 years old and complex in dogs over 5 years old

Question 4

Pathophys of glandular BPH

Answer 4

Circulating testosterone is metabolized by 5α-reductase to 5α-dihydrotestosterone in the prostate, where, through interaction with a receptor protein, it regulates gene expression in the nuclei to control prostatic growth.

Increased number and size of secretory cells but histologic structure and arrangement is still organized

Question 5

Pathophys of complex BPH

Answer 5

As prostate size increases, tissue dihydrotestosterone concentrations decrease which matches decreasing secretory capacity
Decline in glandular dihydrotestosterone is paralleled by an increase in metabolism of androgens in the prostate and increasing numbers of nuclear androgen receptors, resulting in increased response to androgens by the prostate as it ages