Predicting prostate specific antigen failure after radical retropubic prostatectomy for T1c prostate cancer

PURPOSE: Clinicopathological data were reviewed to find a predictor of prostate specific antigen (PSA) failure in Taiwanese patients who had received radical retropubic prostatectomy (RRP) for stage T1c prostate cancer (PC). METHODS: Fifty-five consecutive men who underwent RRP for stage T1c PC were included. The clinical end point was PSA failure (PSA >0.2 ng/ml). Preoperative PSA, free-to-total PSA ratio, prostate volume, PSA density, transrectal sextant biopsy and whole mount of RRP parameters were analyzed for their ability to predict postoperative PSA failure. RESULTS: Fifteen of the 55 patients developed PSA failure during the follow-up period. Those with PSA failure had higher PSA, higher percentage of cancer in biopsies and higher biopsy Gleason score than the freedom from PSA failure group (all P < 0.05). The PSA failure group had higher pathology Gleason score and a higher incidence of extracapsular tumor extension than the freedom from PSA failure group (all P < 0.05). The PSA failure group had a larger tumor volume and higher incidence of combined peripheral lobe with transitional lobe involvement than the freedom from PSA failure group (all P < 0.05). Multivariate analysis revealed that the predictors for PSA failure after RRP were biopsy Gleason score > or =6, tumor volume > or =2.5 ml and PSA > or =10 ng/ml. CONCLUSION: The single most significant predictor for PSA failure in T1c PC patients after RRP was tumor volume > or =2.5 ml.     

Preoperative prediction of surgical margin status in patients with prostate cancer treated by radical prostatectomy.

PURPOSE: We sought to determine the preoperative factors associated with surgical margin status in patients who underwent radical prostatectomy for prostate cancer. PATIENTS AND METHODS: The study group consisted of 339 patients who were treated by radical retropubic prostatectomy and bilateral pelvic lymphadenectomy at the Mayo Clinic. None received preoperative adjuvant therapy. The mean age at the time of surgery was 66 years (range, 45 to 79 years). All specimens were totally embedded and whole-mounted. Positive surgical margin was defined as the presence of cancer cells at the inked margins. Numerous pathologic characteristics in needle biopsies and preoperative clinical findings were analyzed. RESULTS: The overall margin positivity rate was 24%. In univariate analysis, preoperative serum prostate-specific antigen (PSA) level, Gleason score, perineural invasion, percentage of cancer in the biopsy specimens, and number and percentage of biopsy cores involved by cancer were all associated with positive surgical margins. In multivariate analysis, preoperative serum PSA level (odds ratio for a doubling of PSA levels, 1.9; 95% confidence interval, 1.5 to 2.4; P <.001) and percentage of cancer in the biopsy specimens (odds ratio for a 10% increase, 1.3; 95% confidence interval, 1.2 to 1.4; P <.001) were predictive of margin status in radical prostatectomy. With use of preoperative serum PSA level and percentage of cancer in the biopsy as predictors of surgical margins, the overall accuracy as measured by the area under the receiver operating characteristic curve was 0.74. CONCLUSION: Preoperative serum PSA level and percentage of cancer in the biopsy specimens were independently associated with surgical margin status in patients who underwent radical prostatectomy for prostate cancer. The combination of these two factors provides a high level of predictive accuracy for margin status.     

Assessment of relative tumor burden in patients with clinical T1c prostate cancer treated with either external beam or radical prostatectomy.

The choice between external beam radiation therapy (EBRT) or retropubic radical prostatectomy (RPX) as potentially curative treatment for localized carcinoma of the prostate gland (CaP) has not been delineated in randomized studies. Both treatments are more effective if tumor burden is low. We sought to compare these two treatments in patients who had clinical stage T1c (cT1c) lesions and who were thought to have limited tumor burdens pretreatment. Sixty cT1c patients referred to the Department of Radiation Oncology received 66 Gy in 33 sessions of EBRT to localized prostate ports and 59 cT1c patients had RPX. No neoadjuvant nor early adjuvant therapies were prescribed. Radiotherapy success was defined biochemically as a nonrising prostate-specific antigen (PSA) of +/- 1.5 ng/ml. RPX success required a postoperative PSA that was undetectable (PSA <0.2 ng/ml by the Hybritech or Abbott IMx technics). Analysis for nonrising posttreatment PSA levels was performed using Kaplan-Meier and Cox regression methods. Mantel-Haenszel methods were used to determine odds ratios for treatment groups adjusting for potential confounders. We ultimately assessed the relative tumor burden by histologic examination of the RPX specimens. The two treatment groups, although not randomized, were statistically similar in biopsy Gleason Scores, transrectal ultrasonography calculated gland volumes, number of positive biopsy cores, and estimated amount of cancer identified on initial biopsies. Pathologic stage T3 was identified in 25% of RPX patients. Fifty to 60% of RPX specimens histologically had substantial tumor burden and by inference also the EBRT patients. At a median follow-up (F/U) of 36 months, 76% of RPX patients maintained an undetectable PSA, whereas 62% of EBRT patients had a PSA < 1.5 ng/ml at a median F/U of 29 months. The pretreatment PSA values significantly affected EBRT patients' risk of a rising posttreatment PSA level. Twenty-four months after treatment, RPX patients were 3.7 times more likely to maintain a nonrising PSA level (RPX patients posttreatment PSA < 0.2 ng/ml), than EBRT patients (posttreatment PSA < or = 1.5 ng/ml) (p = 0.006). Sixty-six gray in 33 sessions to localized EBRT ports is not sufficiently aggressive therapy for one third or more of patients with cT1c CaP. RPX alone is insufficient therapy for one fourth of cT1c patients. Analysis of the RPX specimens showed that many cT1c tumors have a significant tumor burden. Selection methodologies to separate out patients who require more than conventional dose or type of radiotherapy or more than RPX as monotherapy are needed. Pretreatment PSA and number of positive biopsies may assist this selection process.     

Morbidity of radical retropubic prostatectomy following previous prostate resection

A total of 153 patients with prior prostate surgery underwent a radical retropubic prostatectomy for carcinoma of the prostate. Ninety-seven patients had undergone transurethral resection of the prostate (TURP), and 56 patients had undergone suprapubic transvesical prostatectomy (SPP). In 115 patients, the diagnosis of malignancy was made at the time of transurethral resection or enucleation. No perioperative deaths occurred and no patient suffered rectal injury or ureteral transection. Operative time and blood loss were similar between the TURP and SPP groups and were not different in a group of patients who had not had prior prostate surgery. Early and late complications occurred in eight patients (5.2%), of whom seven had had previous TURP. Complete urinary control was achieved in 96% (147) of the patients; stress incontinence was present in 4% (6 patients); and no patient was totally incontinent. Postoperative complications and the occurrence of stress incontinence were not related to the time elapsed between the previous prostate surgery and the radical prostatectomy. Sexual function was preserved in 32 (71%) of the 45 patients in whom we performed a nerve-sparing radical prostatectomy. Residual cancer was found in the radical prostatectomy specimen in 77 (67%) of the stage A patients. Twenty-nine (25%) of the stage A and 13 (34%) of the stage B patients had pathological evidence of disease extension beyond the confined prostate. Follow-up was 6–92 months, with a mean of 32 months. Four patients died of prostatic cancer, two patients died without cancer, and five have evidence of disease progression; 142 (93%) are alive without evidence of disease. Although radical prostatectomy sometimes is more difficult after previous prostate surgery, operative complication rates, patient morbidity, and the opportunity for surgical cure are not different from those seen in patients with no history of previous prostate Operations. © Wiley-Liss, Inc.     

Quality of life of patients after retropubic radical prostatectomy for prostatic cancer

We studied quality of life in males after retropubil radical prostatectomy (RRP) for local prostatic cancer (LPC). A total of 159 men aged 41-80 years (mean age 67 years) 7-75 months after RRP responded questionnaires. The questions concerned urination and urine retention, erectile function, quality of life, satisfaction with results of operative treatment. 20.75% patients had no urine retention; 59.12% patients had some episodes of such retention, 20.13% had urine retention. In the postoperative period erection recovered in 13.87% patients; 26.42% observed weak force of the urine; 37.11%--improvement of quality of life and 30.19%--aggravation of quality of life. Most of the responders were satisfied with the treatment. Thus, quality of life after RRP worsens. Now, complications of RRP can be corrected and quality of life of such patients can be improved.     

A novel 8-gene panel for prediction of early biochemical recurrence in patients with prostate cancer after radical prostatectomy

Approximately 25% of prostate cancer (PCa) cases experience biochemical recurrence (BCR) following radical prostatectomy (RP). The patients with BCR, especially with BCR ≤2 year after RP (early BCR), are more likely to develop clinical metastasis and castration resistance. Now decision-making regarding BCR after RP relies solely on clinical parameters. We thus attempted to establish an early BCR-risk prediction model by combining a molecular signature with clinicopathological features for guiding clinical decision-making. In this study, an 8-gene signature was derived, and these eight genes were SPTBN2, LGI3, TGM3, LENG9, HAS3, SLC25A27, PCDHGA1, and ADPRHL1. The Kaplan-Meier analysis revealed a significantly prolonged BCR-free survival in the patients with low-risk scores compared to those with high-risk scores in both training and validation datasets. Harrell’s concordance index and time-dependent receiver operating characteristic analysis demonstrated that this gene signature tended to outperform three commercial panels at early BCR prediction. Moreover, this signature was also proven as an independent predictor of BCR-free survival. A nomogram, incorporating the gene signature and clinicopathologic features, was constructed and excellently predicted 1-, 2- and 3-year BCR-free survival of localized PCa patients after RP. Gene set enrichment analysis, tumor immunity, and mRNA expression profiling analysis showed that the high-risk group was more prone to the immunosuppressive microenvironment and impaired DNA damage response than the low-risk group. Collectively, we successfully developed a novel 8-gene signature as a powerful predictor for early BCR after RP and created a prognostic nomogram, which may help inform the clinical management of PCa.     

Preoperative nomogram predicting the 10-year probability of prostate cancer recurrence after radical prostatectomy

An existing preoperative nomogram predicts the probability of prostate cancer recurrence, defined by prostate-specific antigen (PSA), at 5 years after radical prostatectomy based on clinical stage, serum PSA, and biopsy Gleason grade. In an updated and enhanced nomogram, we have extended the predictions to 10 years, added the prognostic information of systematic biopsy results, and enabled the predictions to be adjusted for the year of surgery. Cox regression analysis was used to model the clinical information for 1978 patients treated by two high-volume surgeons from our institution. The nomogram was externally validated on an independent cohort of 1545 patients with a concordance index of 0.79 and was well calibrated with respect to observed outcome. The inclusion of the number of positive and negative biopsy cores enhanced the predictive accuracy of the model. Thus, a new preoperative nomogram provides robust predictions of prostate cancer recurrence up to 10 years after radical prostatectomy.     

机器人辅助前列腺癌根治术治疗大体积前列腺癌的临床应用研究

目的:评估大体积前列腺癌行机器人辅助前列腺癌根治术（RALP）的疗效和安全性,探讨前列腺体积对手术难度的影响。方法:回顾性分析2013年1月至 2017年3月应用机器人辅助前列腺癌根治术治疗大体积前列腺癌35例患者临床资料（前列腺体积≥100 ml）,tPSA水平为6.5~58.5 ng/ml,平均（19.5±8.7） ng/ml,Gleason评分≤6分4例,7分19例（3+4分8例,4+3分11例）,8分7例,9~10分5例。3例有经尿道前列腺电切手术史,5例术前行新辅助内分泌治疗。手术方式均采用经腹膜内入路机器人辅助腹腔镜前列腺癌根治术,高危患者同时行扩大盆腔淋巴结清扫并术后辅助内分泌治疗12~18个月。结果:35例患者均顺利完成手术,无中转开放、直肠损伤及输血病例。手术时间为86~191 min,平均（154±19.8） min;术中出血量45~330 ml,平均（132±60.5） ml;住院时间5~9 d,平均（6.5±0.8） d。术后病理切缘阳性3例（8.6%）;盆腔淋巴结阳性2例（5.7%）。术后漏尿1例,术后2周停止。1例吻合口狭窄,经尿道扩张后排尿通畅。术后1~12个月复查,无生化复发病例,术后3个月有不同程度尿失禁9例（25.7%）,1年内控尿满意33例（94.3%）。结论:大体积前列腺癌手术难度明显增大,需在具备丰富手术经验的前提下完成,采取合理的技术优化可以明显降低手术难度。     

Neoadjuvant docetaxel before radical prostatectomy in patients with high-risk localized prostate cancer.

PURPOSE: To determine the clinical, pathologic, and molecular effects of neoadjuvant docetaxel chemotherapy in high-risk localized prostate cancer. EXPERIMENTAL DESIGN: Patients with biopsy Gleason scores of 8 to 10, serum prostate-specific antigen levels >20 ng/mL, and/or clinical stage T3 disease received weekly docetaxel (36 mg/m2) for 6 months, followed by radical prostatectomy, and were monitored with weekly visits, serum prostate-specific antigen measurements, and endorectal magnetic resonance imaging (MRI). Frozen tumor specimens were collected for microarray analysis. RESULTS: The 19 patients enrolled received 82% of the planned chemotherapy. Toxicity was mild to moderate; fatigue and taste disturbance were common. Prostate-specific antigen declines of >50% were seen in 11 of 19 patients (58%; 95% confidence interval, 33-80%) and endorectal MRI showed maximum tumor volume reduction of at least 25% in 13 of 19 patients (68%; 95% confidence interval, 47-85%) and at least 50% in 4 patients (21%; 95% confidence interval, 6-46%). Sixteen patients completed chemotherapy and had radical prostatectomy; none achieved pathologic complete response. Microarray analysis identified coordinate up-regulation of genes involved in androgen metabolism associated with docetaxel therapy. Specifically, RNA expression for genes that decrease cellular levels of bioactive androgens was coordinately increased in response to chemotherapy. CONCLUSIONS: Neoadjuvant docetaxel administered for 6 months before radical prostatectomy is feasible, well tolerated, and often results in prostate-specific antigen declines of >50% and decreased tumor volume on endorectal MRI. No pathologic complete responses were observed. Altered androgen metabolism may partially account for the noted declines in prostate-specific antigen and be a mechanism for chemotherapy resistance.     

Significant decrease in angiopoietin-1 and angiopoietin-2 after radical prostatectomy in prostate cancer patients

BACKGROUND: Abnormalities in coagulation/platelet activation and angiogenesis are present in all common human cancers. We hypothesized that surgical treatment of prostate cancer would modulate these abnormalities. METHODS: Forty-two men with biopsy-proven prostate cancer were recruited of whom 24 had radical prostatectomy (RP), 12 other treatments and 6 had no treatment. RP patients were followed up from baseline, and samples were collected at 3- and 12-month intervals to assess the effects of the surgery. Plasma was obtained for the measurement of markers of vascular/coagulation/platelet activation (von Willebrand factor (vWf), soluble P selectin (sPsel) (all ELISA), fibrinogen and D-dimer (both nephelometry)) and angiogenesis (vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2) and their receptors s-Flt-1 and s-Tie-2). We also measured the angiogenesis markers VEGF and angiopoietin-1 within platelets (all ELISA). RESULTS: In those undergoing RP, there were changes in plasma VEGF (to 48% of pre-surgery levels at 1 year follow up), Ang-1 (to 82%), Ang-2 (to 27%), sPsel (78%), and fibrinogen (to 91%) at 3 months and/or 12 months (p<0.03). The relative falls in Ang-2, Ang-1 and VEGF were not significant (p=0.448). CONCLUSIONS: RP is associated with a lowering of markers of angiogenesis and platelet activation. This suggests that these pathological processes are driven to a large extent by the tumour and/or tumour-secreted factors, and that removal of the primary growth results in a gradual normalisation of measured indices.     

Insomnia in men treated with radical prostatectomy for prostate cancer

This study assessed the prevalence, clinical characteristics and risk factors for insomnia in patients treated with radical prostatectomy for prostate cancer. A total of 327 patients completed a battery of questionnaires assessing sleep and related issues (i.e. anxiety, depression, fatigue, quality of life). Results indicated that 31.5% of the patients currently reported non-specific sleep difficulties, while 18% met specific criteria for an insomnia syndrome. In most of these latter cases (95%), the insomnia was chronic (duration of 6 months or more). Nearly half of patients with an insomnia syndrome reported that the onset of their sleep difficulties followed the cancer diagnosis. A similar proportion had no comorbid clinical levels of anxiety or depression. Risk factors for the presence of an insomnia syndrome included a younger age, a worse prognosis, and the presence of intestinal, pain, depressive, and androgen blockade-related symptoms. Thus, insomnia is a frequent problem associated with prostate cancer, that often occurs independently of anxiety and depression, but seems to be influenced by the presence of physical and psychological symptoms associated with prostate cancer and its treatment.     

Antegrade radical retropubic prostatectomy with preliminary ligation of vascular pedicles in 614 consecutive patients

BACKGROUND: We present our procedure of antegrade radical retropubic prostatectomy with preliminary ligation of vascular pedicles and assess the time trends of patient characteristics, surgical and oncological outcome in 614 consecutive patients in a single institution over a 12-year period. METHODS: From April 1994 to December 2005, 614 consecutive Japanese patients with cT1-3N0M0 prostate cancer underwent antegrade radical prostatectomy with preliminary ligation of vascular pedicles (dorsal vein complex and prostatic pedicles) prior to the tumor manipulation. Biochemical progression is defined as prostate-specific antigen value over 0.2 ng/ml or the initiation of therapy after surgery. Biochemical progression-free, cancer-specific and overall survival curves were calculated by the Kaplan-Meier method. RESULTS: During the study period pre-operative PSA, clinical T stage, duration of surgery, amount of estimated blood loss have decreased. Pathological stage showed a significant downward migration and the rate of positive surgical margin has also decreased. At a mean follow-up of 48 months, 21 men were dead including eight who died of prostate cancer. Overall and cancer-specific survival rates were 97/99% at 5 years and 89/95% at 10 years, respectively. Neoadjuvant hormonal treatment had no beneficial impact on oncological outcome of patients regardless of clinical stage. In 370 patients treated surgically alone, cancer-specific and biochemical progression-free survival rates were 99.6/80.5% at 5 years and 97.9/73.3% at 10 years for patients with clinical T1/2 disease and 95.5/41.9% at 5 years and 87.5/41.9% at 10 years for those with T3 disease, respectively. In the 370 patients biochemical progression-free survival has been significantly improved over the 12-year period (P < 0.0001). CONCLUSIONS: Antegrade radical prostatectomy with preliminary ligation of vascular pedicles can be performed with excellent oncological outcome.     

Salvage radiotherapy in patients with persisting prostate-specific antigen after radical prostatectomy for prostate cancer

Salvage radiotherapy in patients with persisting prostate-specific antigen (PSA) after radical prostatectomy for prostate cancer offers an approach to reduce local recurrence rates and to improve the rate of biochemical freedom from relapse. 30-70% of these patients experience a decrease in their PSA to an undetectable range; in about 40-50% of these patients, PSA remains stable after 5 years. Therefore, radiation therapy offers these patients an ultimate chance of cure. The pre-irradiation PSA value is of particular importance. The PSA level should not exceed 2 ng/ml because otherwise the rate of distant metastases increases significantly. Serious side effects are apparently low, thus confirming the suitability of this therapeutic approach.     

Declining rates of extracapsular extension after radical prostatectomy: evidence for continued stage migration.

PURPOSE: Prostate-specific antigen (PSA)-based screening is responsible for a profound clinical stage migration in newly detected prostate cancers. Extracapsular extension (ECE) is an important predictor of outcome after radical prostatectomy (RP). We examined trends in the rate of ECE for cancers detected by PSA screening in 731 RP specimens between 1987 and 1997, when screening became routine urologic practice in the United States. METHODS: The rates of ECE were examined in 311 prostates with nonpalpable (stage T1c) disease and 420 with palpable but clinically localized (stage T2) disease. Specimens were step-sectioned and examined by a senior pathologist. Rates of ECE were compared with respect to time, and logistic regression was used to identify predictors of ECE. RESULTS: The rate of ECE decreased from 81% to 36% during the 10-year observation period. Multivariateanalysis involving clinical tumor stage, preoperative serum PSA level, and Gleason score demonstrated that year of treatment was an independent predictor of ECE, with a two-fold reduction of risk occurring during the study period (P <. 001; odds ratio, 1.96; 95% confidence interval, 1.37 to 2.78). CONCLUSION: PSA screening has resulted in a downward trend in pathologic stage in clinically localized prostate cancer, independent of preoperative PSA level, tumor stage, and Gleason score. This time-dependent downward stage migration suggests the need for continuous updating of predictive nomograms and caution in interpreting differences in contemporarily treated patients compared with historical controls. Further study is needed to determine whether this trend will translate into improved disease-free survival.     

经腹膜外腹腔镜下与开放性前列腺癌根治术的临床比较

目的 比较开放性前列腺癌根治术(open radical prostatectomy,ORP)与经腹膜外腹腔镜下前列腺癌根治术(extraperitoneal laparoscopic radical prostatectomy,ELRP)的临床疗效.方法 回顾性分析行前列腺癌根治术的患者65例.ORP组38例行ORP治疗,ELRP组27例行ELRP治疗,比较两组患者术前、围手术期及术后各项指标.结果 ELRP组患者均获成功,无术中转开放手术,手术时长为(135.0±31.7)min,与ORP组的(147.0±40.3)min比较,差异无统计学意义(P>0.05).ELRP组出血量为(210±80)mL,少于对照组的(470±100)mL(P<0.05).在术后住院恢复期中,ELRP组的术后肠功能恢复时间、卧床时间以及住院时间均少于ORP组[(12.1±7.8)h、(9.9±6.7)h、(7.9±2.2)d vs(40.7±10.4)h、(36.3±11.9)h、(15.2±3.4)d,均P<0.05].ORP组尿漏、尿失禁、吻合口狭窄及勃起功能障碍等并发症发生率为63.2%(24/38),而ELRP组并发症发生率为51.9%(14/27),两组比较差异无统计学意义(P>0.05).随访10~12年,两组在完全控尿率及生化复发率方面差异均无统计学意义(均P>0.05).结论 相较于ORP,ELRP是一种更安全有效的前列腺癌根治术术式.术后患者肠功能恢复快、下床时间早、住院时间短,长期随访两者术后完全尿控率及生化复发率无差异.     

Assessing the prognostic significance of transrectal ultrasound extracapsular extension in prostate cancer

AimsTo determine the prognostic value of transrectal ultrasound (TRUS)-detected extraprostatic disease for prostate cancer in patients receiving radical external-beam radiation therapy (EBRT).Materials and methodsA chart review of 181 patients treated with radical EBRT for prostate cancer was conducted. All patients underwent TRUS assessment by one radiologist. The median radiation dose delivered to the prostate was 66 Gy (range 53–70 Gy) in 33 fractions (range 20–39 fractions). Median follow-up time for all patients was 6.5 years. Sixty-four (35%) out of 181 patients were found to have extracapsular disease on TRUS. Clinical relapse was defined as the first occurrence of either salvage hormonal therapy administration by the treating oncologist or clinical, radiological, and/or pathologic evidence of recurrent or progressive disease. In terms of biochemical failure, two prognostic variable analyses were carried out using both the American Society for Therapeutic Radiology and Oncology (ASTRO) consensus guidelines and the Houston definition of biochemical failure. The primary end point for the prognostic variable analyses was time to first clinical or biochemical failure (CBF).ResultsFor time to CBF using the ASTRO consensus guidelines for biochemical failure, univariable analysis revealed that the prostate-specific antigen (PSA) (P = 0.018), clinical T stage (P = 0.002), Gleason score (P = 0.021), adjuvant hormonal therapy (P = 0.032) and TRUS T staging (P = 0.0001) were statistically significant prognostic factors. On multivariable analysis, clinical T stage (P = 0.051) was of borderline statistical significance, whereas PSA (P = 0.036), TRUS T stage (P = 0.0002) and adjuvant hormonal therapy (P = 0.015) were found to be independent prognostic factors. For time to CBF using the Houston definition of biochemical failure, univariable analysis revealed that PSA (P = 0.001), Gleason score (P = 0.026) and prostate volume (P = 0.013) were statistically significant prognostic factors. On multivariable analysis, PSA (P = 0.002), Gleason score (P = 0.012), and adjuvant hormonal therapy (P = 0.041) were found to be independent prognostic factors. TRUS T staging was not found to be independently significant.ConclusionsA clear role for TRUS staging as an independent prognostic factor, in the setting of other more established variables, such as Gleason grade, PSA, and digital rectal examination (DRE) T stage, was not confirmed in this study population.     

Preoperative parameters to predict tumor volume in Japanese patients with nonpalpable prostate cancer

Methods. In 40 patients with T1c cancers treated with radical prostatectomy, the pretreatment parameters of serum PSA, PSA density, biopsy Gleason score, and number of cancer-positive cores were determined and compared with the histological features in the surgical specimens. Pretreatment parameters were also determined in patients whose biopsy Gleason score was 6 or less, and whose biopsy specimen contained one or two cancer-positive cores, with 50% or less cancer involvement in any cancer-positive cores. Results. At the time of radical prostatectomy, 73% of patients had organ-confined disease. When insignificant cancer was defined as a volume of less than 0.5 cm³ and a Gleason score of 6 or less, in 9 of the 40 (23%) patients with clinical T1c disease, the cancer was clinically insignificant. Multiple regression analysis of the pretreatment variables, including pretreatment PSA level, PSA density, and number of cancer-positive cores demonstrated that the pretreatment PSA level and number of cancer-positive cores were independent factors that predicted tumor volume. From the biopsy features, 19 patients were assessed as having clinically insignificant disease. Nine (47%) of them had tumors of less than 0.5 cm³, whereas 2 (11%) had tumors of more than 2 cm³. The values for pretreatment PSA density and PSA density adjusted for the transition zone volume for those with a cancer volume of 0.5 cm³ or more were significantly higher than the values for those patients with a cancer volume of less than 0.5 cm³. Conclusion. T1c cancers in Japanese patients included various cancers, from clinically insignificant to locally advanced ones. Pretreatment PSA level and the number of cancer-positive cores are useful parameters with which to predict cancer volume in the surgical specimen. Received: September 14, 2001 / Accepted: January 7, 2002