Importance of Transition Zone Prostate Biopsies in Patients with Gray-Zone PSA Levels Undergoing the Ultrasound-Guided Systematic Ten-Biopsy Regimen for the First Time

Is a sampling transition zone important to increase the detection of prostate cancer in systematic prostatic biopsies?

BACKGROUND

Use of transrectal ultrasound (US)-guided biopsies improved diagnosis and treatment for patients with high prostate-specific antigen (PSA) or abnormal digital rectal exam (DRE).

PURPOSE

To investigate whether taking two transition zone (TZ) biopsies in addition to routine prostate double-sextant biopsies (12-cores) would improve detection rates of prostate cancer (PCa).

MATERIAL AND METHODS

A retrospective analysis of 1107 in a single institution database after Institutional Review Board approval, which underwent US-guided prostate biopsies from January 2014 to June 2016. All patients with suspected PCa based on positive DRE or high PSA submitted to US-guided prostate biopsy (double-sextant 12-cores alone and 12-cores with two TZ extra cores) were included.

RESULTS

A total of 1107 patients were included; 120 patients underwent double-sextant 12-cores alone and 987 underwent 12-cores with two TZ extra cores. Among patients submitted to two TZ extra cores, TZs of 755 (76.5%) patients were negative to neoplasia and 232 (23.5%) were positive to neoplasia. Among these patients, 26 (2.6%) had their final Gleason score increased with TZ core; TZ fragments of 20 (2.0%) patients led to a treatment change (re biopsy, active surveillance or from active surveillance to radiation therapy or radical prostatectomy). When the complication rate is analyzed (with or without hospital admission), among the patients submitted to TZ cores, 259 (26.2%) complications were observed; between those submitted to double-sextant 12-cores, 26 (21.7%) complications were observed (P=0.279).

CONCLUSION

Extended core biopsy protocol with two TZ extra fragments improves detection rates of cancer when compared to double-sextant biopsy protocol without increasing complication rates. TZ routine cores should be considered.

Impact of extended prostate biopsy including apical anterior region for cancer detection and prediction of surgical margin status for radical prostatectomy

Objectives

We investigated diagnostic yield of initial biopsy and repeated biopsy including apical cores.

Methods

We investigated 573 consecutive men with PSA of ≤20 ng/ml who underwent prostate biopsy between 2004 and 2013. The initial 14-core biopsy consisted of the sextant type, lateral sites at the base and middle, lateral apices (la) at anterior horn sites, and apical anterior sites (aa). The repeated 18-core biopsy consisted of the initial 14-core biopsy with four transition zone (TZ) sites at the base (tzb) and middle (tzm).

Results

Prostate cancer was diagnosed in 178 (38.9%) of 458 men with the initial 14-core biopsy, and 44 (38.3%) of 115 men with the repeated 18-core biopsy. In the initial biopsy setting, the unique cancer detection rate was high in apical sites (apex, la, and aa: 6.2%, 6.2% and 5.1%, respectively). In the repeated setting, it was high in the TZ site in addition to the apical site (apex, la, aa, tzm, and tzb: 6.8%, 6.8%, 11.4%, 9.1% and 11.4%, respectively). The positive SM rate at the apex was higher in patients whose cancer was detected only in sites other than the sextant region than for those in the sextant region (36.4% vs. 14.8%, P = 0.037).

Conclusions

The initial 14-core and the repeated 18-core biopsy scheme including apical anterior cores are feasible for prostate cancer detection. We propose that apical biopsy cores can be used to predict not only the existence of cancer but also surgical margin status at the apex.

Anatomy of the prostate revisited: implications for prostate biopsy and zonal origins of prostate cancer

Over the past 25 years, our understanding of prostatic disease has evolved secondary to the increased detection, treatment and study of both benign and neoplastic prostatic lesions. The advent of aggressive prostate-specific antigen screening and standardization of extended transrectal needle biopsy protocols has resulted in significant stage migration and earlier detection of prostate cancers, a growing proportion of which are lower-volume posterior peripheral zone tumours. Consequently, an increased incidence of anterior-predominant prostate cancers has been observed. Given the histomorphological complexity of the prostate, these developments have necessitated a reconsideration of prostatic anatomy, biopsy strategies in the detection of anterior tumours and the determination and relevance of zonal origin in prostate cancer. This review will provide a contemporary update of these topics, while highlighting specific areas in which a keen understanding of prostatic histoanatomy may influence biopsy interpretation.

Do prostatic transition zone tumors have a distinct morphology?

Previous studies have proposed that the morphologic spectrum of prostatic glands of variable size with tall columnar cells displaying basally oriented nuclei and clear to pale pink cytoplasm (TZ-LOOK) is characteristic of the well to moderately differentiated component of transition zone (TZ) tumors. However, the specificity of these findings has not been well studied. In a recent report, we identified dominant peripheral zone (PZ) and TZ tumors situated anterior to the prostatic urethra. Currently, we evaluate the histopathologic features of 215 dominant tumors, including 63 TZ and 73 anterior PZ lesions and an additional cohort of 79 posterior PZ tumors, in radical prostatectomy specimens, to identify the prevalence of this morphology in tumors of different zonal origin. Each dominant tumor was assigned a TZ-LOOK extent score of 0 to 4, with 0 = no such morphology, 1 = 1% to 25%, 2 = 26% to 50%, 3 = 51% to 75%, and 4 = >75%. Overall, 121/215 (56%) tumors showed some degree of this histology, including 56 of 63 (89%) TZ tumors and 65 of 152 (43%) PZ tumors (P<0.0001). Thirty-seven of 215 (17%) lesions had scores of 3 to 4, with 31 (84%) of these being of TZ origin. However, only 31/63 (49%) TZ tumors had >50% TZ-LOOK. Among PZ tumors, 6/152 (4%) had predominant (>50%) TZ-LOOK morphology, yet 23/152 (15%) of all PZ tumors and 23/65 (35%) of PZ tumors displaying any degree of TZ-LOOK had scores of 2 to 3 (>25%; nonfocal). In tumors of both zones with predominant (scores 3 to 4; >50%) TZ-LOOK histology, darker glands of usual acinar adenocarcinoma was often seen at the periphery. Conversely, in tumors with nonpredominant TZ-LOOK (scores 1 to 2; 50% of this histology are very likely of TZ origin, but this scenario occurs in only half of TZ tumors. Importantly, the TZ-LOOK is nonfocal in up to 35% of PZ tumors exhibiting any degree of this morphology. Given this lack of specificity, caution should be exercised in assigning zone of origin based on this histologic appearance, especially in limited samples such as prostate needle biopsy.