Department of Urology, University Vita-Salute, Scientific Institute San Raffaele, Milan, Italy.
Eur Urol. 2010 Jan;57(1):1-8. doi: 10.1016/j.eururo.2009.08.011. Epub 2009 Aug 19.
The most efficient number and location of prostate biopsies remains a matter of debate.
To identify the combination (number and location) of sampling sites that permits the detection of 95% of the prostate cancers (PCa) detected by a 24-core biopsy (24PBx).
DESIGN, SETTING, AND PARTICIPANTS: Six hundred and seventeen consecutive patients with a suspicion of PCa were prospectively enrolled.
A transrectal ultrasound-guided systematic 24PBx was prospectively performed with local anesthesia in an outpatient setting. The 24PBx was obtained by the overlapping of medial sextant, lateral sextant, octant subcapsular, and quadrant transition cores. Before fixation, each single core was individually marked and inked according to the prostatic location sampled.
We relied on a classification and regression tree analysis to identify four subgroups of patients with different PCa detection risk at initial biopsy, according to their clinical characteristics. Subsequently, we set the cancer-positive rate of the 24PBx at 100% and calculated PCa detection rates for 255 possible combinations of sampling sites. We selected the most advantageous biopsy scheme (defined as the combination of sampling sites that detected 95% of all the cancers with the minimal number of biopsy cores) for each patient subgroup. Finally, we internally validated the tumor detection rates by using the 10-fold cross-validation method.
The 24PBx detected PCa in 289 patients (46.8%). The analysis revealed that the most advantageous schemes for patients with a negative digital rectal exam (DRE), prostate volume (PV) < or =60 cm(3), and age < or =65 yr was a combination of a 16-core biopsy. For patients with a negative DRE, PV < or =60 cm(3), and age >65 yr or a negative DRE and PV >60 cm(3), the most advantageous scheme was two different combinations of a 14-core biopsy. Finally, the sampling that permits detection of 95% of cancers in patients with a positive DRE was a combination of a 10-core biopsy.
The most beneficial scheme varied according to the clinical characteristics of the patients. We propose a user-friendly flowchart to identify the most advantageous set of sampling sites according to patients' characteristics.
最有效的前列腺活检数量和位置仍然存在争议。
确定能够检测到 24 核心活检（24PBx）检测到的 95%前列腺癌（PCa）的采样部位组合（数量和位置）。
设计、设置和参与者：617 例怀疑患有 PCa 的连续患者前瞻性入组。
在门诊环境下，经直肠超声引导下对每位患者进行前瞻性、系统性的 24PBx，局部麻醉。24PBx 通过重叠内侧六分体、外侧六分体、八分体包膜下和四分体过渡核心来获得。在固定之前，根据采样的前列腺位置，对每个单个核心进行单独标记和墨迹。
我们依靠分类和回归树分析，根据患者的临床特征，将不同初始活检 PCa 检出风险的患者分为四个亚组。随后，我们将 24PBx 的阳性率设定为 100%，并计算了 255 种可能的采样部位组合的 PCa 检出率。我们为每个患者亚组选择了最有利的活检方案（定义为检测所有癌症所需活检核心数最少的采样部位组合）。最后，我们使用 10 折交叉验证方法对内部分叉验证肿瘤检出率。
24PBx 在 289 例患者（46.8%）中检测到 PCa。分析表明，对于指诊（DRE）阴性、前列腺体积（PV）≤60cm3 和年龄≤65 岁的患者，最有利的方案是 16 核心活检。对于 DRE 阴性、PV≤60cm3 且年龄＞65 岁或 DRE 阴性和 PV＞60cm3 的患者，最有利的方案是两种不同的 14 核心活检组合。最后，在 DRE 阳性的患者中，检测到 95%的癌症的采样是 10 核心活检的组合。
最有益的方案因患者的临床特征而异。我们提出了一个用户友好的流程图，根据患者的特征来确定最有利的采样部位组合。
