RESULTS: PCa was detected on biopsy in 192 39.8% patients. PCa was detected only in the TZ for 10 patients 5.2%, only in the PZ for 69 patients 35.9%, and in both the TZ and PZ for 113 patients 58.9%. Obtaining a biopsy only from the TZ resulted in a significantly lower cancer detection rate than obtaining the biopsy only from the PZ or from the combined PZ and TZ P < .05. High GSs ≥ 7 were found in 3 of 10 patients 30% with PCa detected in the TZ, 29 of 69 patients 42% with PCa detected in the PZ, and 90 of 113 patients 79.6% with PCa detected in the combined TZ and PZ. Among the patients with PSA levels < 10 ng/mL, none of the 4 patients with PCa detected only in the TZ had GSs ≥ 7; however, 14 of 41 patients 34.1% with PCa detected only in the PZ and 18 of 32 patients 56.3% with PCa detected in the combined TZ and PZ had GSs ≥ 7. Patients with a biopsy only from the TZ had significantly fewer GSs ≥ 7 than patients with a biopsy only from the PZ or from the combined PZ and TZ in this PSA rangeP < .05.CONCLUSION: It may be possible to omit a prostate biopsy from the TZ for patients with serum PSA < 10 ng/mL.
A transition zone biopsy is when tissue is taken from the middle part of the prostate. This part usually has benign elements from BPH and not cancer. I usually biopsy the transition zone in patients that have had a negative biopsy and need a repeat biopsy for a rising PSA.
From memory, I have seen patients with transition only prostate cancer and have performed robotic prostatectomy on them. The ones that had a surprising (more than we would expect) amount of prostate cancer were the ones with the PSA over 10.
I will continue to perform the prostate biopsy as I have done after this article, but will think of ways of looking into this more with my practice. I do not think the morbidity of 2 extra transition zone biopsies is very different than a standard biopsy. My standard biopsy currently has 12 cores with 2 extra cores from the anterior apex, which has led to a better cancer detection rate and I have used the presence of cancer at the apex to better delineate the amount of tissue I leave on the anterior prostate apex.