To improve prostate cancer control, we performed RRP-WR for 90 cases of preoperative locally confined prostate cancer, and we evaluated the surgical outcome by morbidity and curability with surgical margin status pathologically. We tried to demonstrate preliminary clinical outcomes by achievement of undetectable PSA and BCR without immediate adjuvant therapy after surgery.
Half the procedures took more than 4 h to complete, partly because of the time taken for lymph node dissection. We routinely performed obturator lymph node dissection, and internal iliac lymph node dissection was also implemented for high-risk cases by NCCN classification. Lymph node dissection in radical prostatectomy is mainly for the purpose of staging, but for advanced cases it may be therapeutic. Only four instances of lymph node metastasis were found in this series of cases, and three of these four patients achieved undetectable postoperative PSA, two without BCR at 3 and 30 months, and the other two cases recurred biochemically at 25 and 47 months after surgery.
Although blood loss was not trivially small, it could be deemed acceptable because no allo-transfusion was required and the loss level of less than 1,000 ml is lower than or comparable to the values of 800 to 1,650 ml noted in previous reports[17, 18]. The number of days with urethral catheter presence after surgery and the number of days spent in the hospital after surgery were also not longer than those in previous reports. It takes time to recover from incontinence (6.5% required more than two pads a day at 3 months after surgery), but after 6 months, incontinence with more than one pad a day was seen only in three cases with early BCR. Another report on this procedure also mentioned that a period of 6 months is required to recover continence. Thus, the procedure can be seen as feasible.
Kupelian et al. reported that intracapsular pSM for organ-confined (pT2) disease from radical prostatectomy with inadvertent incision through the capsule in a tumor was 18%. Kordon et al. also reported that among 1,378 cases of pT2, 16.9% showed pSM. Even with minor modification to reduce apical pSM, pSM in organ-confined disease could not be eliminated completely. In this study, we achieved resection without pSM for all pT2 patients through RRP-WR, although the number of cases was small. Locating the rectourethral muscle enabled clarification not only of the urethral sphincter’s location, but also that of the prostate apex. This is a major advantage of the procedure for resection without pSM. However, most cases with organ-confined disease are in a good risk group for which more than 10 years of survival can be expected with any definitive monotherapy[1, 22]. In terms of control for organ-confined (pT2) prostate cancer, we consider that this procedure would be as successful as the regular RRP procedure, although more would cause erectile dysfunction, which was not analyzed in this work.
For patients with pT3 and pT4, curative resection was achieved without pSM at a rate of 77.5%. Inagaki et al. reported a no-pSM rate of 38.7% for 106 cases of pT3a and pT3b that had been diagnosed as cT1 and cT2 preoperatively, and Kordon et al. also reported that the incidence of no pSM in 288 pT3a cases was 52.1%, which is much lower than the respective 82.1% and 85.7% values seen in our series.
This increase in the ratio of resection without pSM for cases with pT3 and pT4 seems to have contributed to better cancer control. In this series, pT3 and pT4 cases without pSM demonstrated an 84.5% BCR-free survival rate 2 years after surgery, which is much higher than the 37.5% value seen for cases with pSM. Since the follow-up period is short, we also evaluated achievement of undetectable PSA after surgery, which has been reported as a significant predictor of BCR in pT3 cases after surgery by multivariate analysis, and found a figure of 92.5% for cases with pT3 and pT4. Recently, Preston et al. reported the prognostic significance of curative resection for cases with non organ-confined disease by radical prostatectomy. They demonstrated that cases with completely resected extraprostatic disease had a higher probability of BCR-free survival (86 % at 5 years after surgery) than those with capsular incision into tumors of organ-confined disease did (77 % at 5 years after surgery). Thus, with RRP-WR we can expect better prognosis of locally confined prostate cancer with EPE treated surgically than previous reports indicate, although it is necessary to confirm the long-term results for a large number of cases before making a firm conclusion.
In terms of the indication of this procedure compared to regular RRP, we consider that locally confined but non-organ-confined or no seminal vesicle involvement (pT3a) cases may deserve the advantage of the procedure as opposed to regular RRP. As mentioned above, for good risk cases [such as those with an initial PSA of less than 10, a Gleason score of less than 7 or organ-confinement (pT2)], the regular and well-established procedure of radical prostatectomy is good enough to achieve a survival period of 10 years. The authors demonstrated 10-year cause-specific survival greater than 95% for pT2 cases treated by radical prostatectomy. Erectile dysfunction, which cannot be avoided because of the nature of wide resection, is one disadvantage of this procedure, although we did not assess erectile dysfunction in this work. Thus, for pT2 cases, nerve-sparing prostatectomy results in a better risk/benefit ratio. Cases of pT3b (seminal vesicle invasion) and pT4 (direct invasion to surrounding organ or muscle) had poor outcomes even after resection without pSM from pathological evaluation of prostatectomy specimens. As preoperative evaluation cannot ascertain beyond doubt whether the disease is pT3a, such cases cannot be chosen before the operation. Without pathological evaluation of the entire prostate after removal by radical prostatectomy, it is also not possible to tell at the preoperative stage whether the disease is organ-confined.
In this series, concerning the T category, we found that most of the cases (62 of 90 cases) were underestimated preoperatively compared to the results from the prostatectomy specimens. We reevaluate the cases of this study using the Japan PC table to find the reason for this discrepancy. As the Japan PC table and NCCN risk criteria seem to correlate with each other in this series, our results are also in line with the prediction of the table. Thus, we confirmed that simple clinical T category cannot tell the pathological results in prostatectomy specimens and that the Japan PC Table is useful to determine the probability of EPE of clinically organ-confined disease.
Also in our series, 30 (40.5%) of 74 cT1c and cT2 cases were pT3 and worse pathologically. Among these 30 preoperatively underestimated cases, successful removal was achieved in 23 (76.7%) by RRP-WR. More than half of the cases in this series did not require RRP-WR to achieve resection without pSM, but 23 of 74 cases (31.1%) with cT1c and cT2 would have failed if the procedure had not been performed. Although it is difficult to expect a good prognosis for cases with pT3b and pT4 from radical prostatectomy alone, even without pSM, 18 of 22 patients with pT3a that had been diagnosed as cT1c or cT2 preoperatively deserved the advantage of RRP-WR because prostate and prostate cancer removal was achieved without pSM.