Arai Y, Okubo K, Terada N, Matsuta Y, Egawa S, Kuwao S, Ogura K
Department of Urology, Kurashiki Central Hospital, 1-1-1 Miwa, Kurashiki 710-8602, Japan.
Prostate. 2001 Feb 1;46(2):134-41. doi: 10.1002/1097-0045(20010201)46:2<134::aid-pros1017>3.0.co;2-9.
Estimates of volume-weighted mean nuclear volume (MNV) are the only means by which unbiased estimates of three-dimensional parameters can be obtained from a single two-dimensional section, with stereological methods. The present study was conducted to elucidate the role of MNV in predicting tumor biology for patients treated with radical prostatectomy.
A retrospective prognostic study of 71 patients with T1/T2 disease, treated with radical prostatectomy alone, was performed. MNV was estimated using biopsy specimens based on a stereological method, and was compared with other preoperative clinical variables. For patients with prostate-specific antigen (PSA) failure, we determined the correlation of MNV with PSA doubling time (PSA DT) which was calculated using PSA values obtained with an ultrasensitive assay.
Mean MNVs for pathologically organ-confined and non-organ-confined tumors were 198.9 and 236.3 microm3, respectively; this difference was significant (P = 0.0364). Univariate analysis showed that PSA, MNV, and Gleason score were significant predictors of prognosis (P = 0.0126, 0.0148, and 0.0375, respectively). Multivariate analysis revealed that MNV and preoperative PSA were powerful independent predictors of prognosis (P = 0.0160 and P = 0.0147, respectively), but the Gleason score was not correlated with prognosis (P = 0.4120). For patients with PSA failure, PSA DT was significantly correlated with MNV (r = -0.597, P = 0.0099). When these patients were classified using median PSA DT at 6 months into two groups, MNV was significantly greater in PSA rapid-riser group than in the slow-riser group (P = 0.0008), but no differences were observed between these groups in PSA, the Gleason score, or cancer volume.
The findings of the present study suggest that MNV is a powerful predictor of PSA failure for patients with clinically organ-confined disease treated with radical prostatectomy. More importantly, they suggest that MNV can be a useful new parameter for prediction of tumor biology for patients with PSA failure after radical prostatectomy.
体积加权平均核体积（MNV）的估计是唯一能够通过体视学方法从单个二维切片获得三维参数无偏估计的手段。本研究旨在阐明MNV在预测接受根治性前列腺切除术患者肿瘤生物学特性中的作用。
对71例仅接受根治性前列腺切除术的T1/T2期疾病患者进行回顾性预后研究。基于体视学方法，使用活检标本估计MNV，并将其与其他术前临床变量进行比较。对于前列腺特异性抗原（PSA）失败的患者，我们确定了MNV与PSA倍增时间（PSA DT）的相关性，PSA DT使用超敏检测获得的PSA值进行计算。
病理局限于器官内和非器官内肿瘤的平均MNV分别为198.9和236.3立方微米；差异具有统计学意义（P = 0.0364）。单因素分析显示，PSA、MNV和Gleason评分是预后的显著预测因素（分别为P = 0.0126、0.0148和0.0375）。多因素分析显示，MNV和术前PSA是预后的有力独立预测因素（分别为P = 0.0160和P = 0.0147），但Gleason评分与预后无关（P = 0.4120）。对于PSA失败的患者，PSA DT与MNV显著相关（r = -0.597，P = 0.0099）。当根据6个月时的中位PSA DT将这些患者分为两组时，PSA快速升高组的MNV显著高于缓慢升高组（P = 0.0008），但两组在PSA、Gleason评分或癌体积方面未观察到差异。
本研究结果表明，MNV是接受根治性前列腺切除术的临床局限于器官内疾病患者PSA失败的有力预测因素。更重要的是，它们表明MNV可能是预测根治性前列腺切除术后PSA失败患者肿瘤生物学特性的一个有用的新参数。
