Cupp M R, Bostwick D G, Myers R P, Oesterling J E
Department of Urology, Mayo Clinic, Rochester, Minnesota, USA.
J Urol. 1995 May;153(5):1543-8.
Previous studies suggest that prostate cancer with a volume of 0.5 ml. or less and a Gleason score of less than 7 may be clinically insignificant and may be managed with watchful waiting. A proposed method of determining the volume of cancer in the prostate gland has been the grade and volume of cancer present in the transrectal needle biopsy specimen. Volume of cancer in the biopsy specimen as a predictor of volume of cancer in the prostate gland was studied in 130 men who underwent radical retropubic prostatectomy for adenocarcinoma. Of the men 46 (35%) had clinical stage T1c (nonpalpable) disease, while 84 (65%) had clinical stage T2 (palpable) disease. Each radical prostatectomy specimen was whole-mounted and step-sectioned for accurate cancer volume determination. Three parameters for measuring volume of cancer in the biopsy specimen (percentage of biopsy cores involved, millimeters of cancer per biopsy core and percentage of cancer in the biopsy specimen) were determined and compared by Spearman rank correlation analysis. The percentage of cancer in the biopsy specimen was marginally better than the percentage of cores involved and the millimeters of cancer per biopsy core as a predictor of cancer volume in the radical prostatectomy specimen. While regression analysis revealed a direct correlation between the volume of cancer in the biopsy and radical prostatectomy specimens (r = 0.51), there was significant variability in prostate cancer volume for a given percentage of cancer in the biopsy specimen since the standard error of the estimate was 6.1 ml. Of the 13 patients with 5% or less cancer volume and a Gleason score of less than 7 in the biopsy specimen 1 (8%) had a cancer smaller than 0.5 ml. in volume in the radical prostatectomy specimen. Therefore, the risk of removing clinically insignificant prostate cancer, even when the biopsy parameter indicates low volume disease, is less than 10%. Overall, only 3 study patients (2.3%) had a prostate cancer volume of less than 0.5 ml. With 97.7% of the men having a clinically significant cancer by a volume criterion, it is apparent that the majority of clinically insignificant prostate cancers remained undetected and untreated. Currently, transrectal needle biopsy does not provide adequate information for differentiating between clinically insignificant and life threatening prostate cancer on an individual basis.
以往研究表明，体积为0.5毫升或更小且Gleason评分低于7分的前列腺癌在临床上可能无显著意义，可采用密切观察等待的方式处理。一种确定前列腺癌体积的建议方法是经直肠穿刺活检标本中癌的分级和体积。对130例行根治性耻骨后前列腺切除术治疗腺癌的男性患者，研究了活检标本中癌体积作为前列腺癌体积预测指标的情况。这些男性患者中，46例（35%）为临床T1c期（不可触及）疾病，84例（65%）为临床T2期（可触及）疾病。对每个根治性前列腺切除标本进行整体包埋并进行连续切片，以准确测定癌体积。通过Spearman等级相关分析确定并比较了测量活检标本中癌体积的三个参数（活检组织条块受累百分比、每个活检组织条块中的癌毫米数以及活检标本中的癌百分比）。活检标本中的癌百分比作为根治性前列腺切除标本中癌体积的预测指标，略优于活检组织条块受累百分比和每个活检组织条块中的癌毫米数。虽然回归分析显示活检标本和根治性前列腺切除标本中的癌体积之间存在直接相关性（r = 0.51），但对于活检标本中给定百分比的癌，前列腺癌体积存在显著变异性，因为估计的标准误差为6.1毫升。在活检标本中癌体积为5%或更小且Gleason评分低于7分的13例患者中，1例（8%）在根治性前列腺切除标本中的癌体积小于0.5毫升。因此，即使活检参数显示疾病体积较小，切除临床上无显著意义的前列腺癌的风险也小于10%。总体而言，只有3例研究患者（2.3%）的前列腺癌体积小于0.5毫升。由于97.7%的男性根据体积标准患有临床上有意义的癌症，显然大多数临床上无显著意义的前列腺癌仍未被发现和治疗。目前，经直肠穿刺活检无法提供足够信息以个体区分临床上无显著意义和危及生命的前列腺癌。
