Optimum prostate Bx: Have we finally agreed?

Dr. Gomella is chairman of the department of urology and associate director of clinical affairs, Jefferson Kimmel Cancer Center, Thomas Jefferson University, Philadelphia.

Prostate cancer is a fairly unique malignancy, with multifocal tumors found in the majority of radical prostatectomy specimens. The optimum prostate biopsy schema has evolved to maximize the detection of clinically important cancers. Not only has this been a scientific question but has become a contentious socioeconomic and reimbursement issue as well. A 2012 review suggested that urologists’ self-referral to “in-office” pathology laboratories led to more specimens per biopsy session and lower overall cancer detection rates (Health Aff 2012; 31:741-9).

Dr. Olsson and associates presented at the 2013 Genitourinary Cancers Symposium what appears to be the most extensive number of data points ever analyzed in the field of prostate cancer research (see page 00). The study included more than 4.2 million specimens from 437,937 patients who underwent prostate biopsy and compared utilization data between urologists who used their own labs and those from a national reference lab. They found no difference between the numbers of biopsy cores submitted with an increased trend toward 10 to 12 cores over the last 4 years. The positive biopsy rate of approximately 40% was also similar between the two groups.

The AUA sanctioned a multidisciplinary committee that has generated a “prostate biopsy white paper” (J Urol Feb. 25, 2013 [Epub ahead of print]). The group reviewed the available literature to define the minimum number of cores needed to accurately diagnose prostate cancer and determine how many site-labeled jars are necessary for patient care. They concluded that a 12-core systematic biopsy that incorporates apical and far-lateral cores in the template distribution allows maximal cancer detection while minimizing the detection of indolent prostate cancers. However, the review could not provide evidence that individual site-specific labeling of cores benefited clinical decision making. It recommended packaging no more than two cores in each jar to avoid reduction of cancer detection rates through inadequate tissue sampling.

Since the days of the digitally directed prostate nodule biopsy using the Vim-Silverman needle, the optimum prostate biopsy strategy has evolved. In addition to transrectal ultrasound guidance, the number of cores in the initial prostate biopsy has increased from the sextant biopsy to what is considered to be the standard of care today, namely the 12-core systematic transrectal ultrasound-guided biopsy.