Impact of Learning Curve in Laparoscopic Radical Prostatectomy on Margin Status: Prospective Study of First 100 Procedures Performed by One Surgeon

Learning curves in laparoscopic and robot-assisted prostate surgery: a systematic search and review

PURPOSE

To perform a systematic search and review of the available literature on the learning curves (LCs) in laparoscopic and robot-assisted prostate surgery.

METHODS

Medline was systematically searched from 1946 to January 2021 to detect all studies in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement, reporting on the LC in laparoscopic radical prostatectomy (LRP), laparoscopic simple prostatectomy (LSP), robot-assisted radical prostatectomy (RARP) and robot-assisted simple prostatectomy (RSP).

RESULTS

In total, 47 studies were included for qualitative synthesis evaluating a single technique (LRP, RARP, LSP, RSP; 45 studies) or two techniques (LRP and RARP; 2 studies). All studies evaluated outcomes on real patients. RARP was the most widely investigated technique (30 studies), followed by LRP (17 studies), LSP (1 study), and RSP (1 study). In LRP, the reported LC based on operative time; estimated blood loss; length of hospital stay; positive surgical margin; biochemical recurrence; overall complication rate; and urinary continence rate ranged 40-250, 80-250, 58-200, 50-350, 110-350, 55-250, 70-350 cases, respectively. In RARP, the corresponding ranges were 16-300, 20-300, 25-200, 50-400, 40-100, 20-250, 30-200, while LC for potency rates was 80-90 cases.

CONCLUSIONS

The definition of LC for laparoscopic and robot-assisted prostate surgery is not well defined with various metrics used among studies. Nevertheless, LCs appear to be steep and continuous. Implementation of training programs/standardization of the techniques is necessary to improve outcomes.

Five year biochemical recurrence free survival for intermediate risk prostate cancer after radical prostatectomy, external beam radiation therapy or permanent seed implantation

OBJECTIVE

To compare biochemical recurrence-free survival (bRFS) for patients with intermediate-risk prostate cancer treated by retropubic radical prostatectomy (RRP), laparoscopic radical prostatectomy (LRP), external beam radiation therapy (RT), or permanent seed implantation (PI).

METHODS

Patients treated for intermediate-risk prostate cancer per National Comprehensive Cancer Network guidelines from 1996 to 2005 were studied. Variables potentially affecting bRFS were examined using univariate and multivariate Cox regression analysis. Five-year bRFS rates were calculated by actuarial methods; bRFS was calculated using Kaplan-Meier analysis. Nadir +2 definition of biochemical failure was used for RT and PI patients; a PSA ≥ 0.4 ng/mL was used for radical prostatectomy (RP) patients. Time to initiation of salvage therapy was compared for each treatment group using the Kruskal-Wallis test.

RESULTS

Nine-hundred seventy-nine patients were analyzed with a median follow-up of 65 months. Five years bRFS rate was 82.8% for all patients (89.5% PI, 85.7% RT, 79.9% RRP, and 60.2% LRP). Patients treated by LRP had significantly worse bRFS than RT (P < .0001), PI (P < .0001), or RRP patients (P = .0038). Treatment modality (P < .0001) and average number of PSA tests per year (P < .0001) were the only independent predictors of bRFS on multivariate analysis. Median time to initiation of salvage therapy from time of treatment was 28.6 months for all patients (26.1 RP, 21.0 LRP, 47.4 PI, 47.8 RT; P < .0001).

CONCLUSIONS

Patients with intermediate-risk prostate cancer choosing PI, RT, or RRP appear to have improved 5-year bRFS and delayed salvage therapy compared with LRP.

The learning curve for robot-assisted radical cystectomy

OBJECTIVE

Robot-assisted radical cystectomy has the potential to cure patients from bladder cancer while offering the benefits of minimally invasive surgery. We sought to evaluate the learning curve for this technically demanding procedure.

MATERIALS AND METHODS

Robot-assisted radical cystectomy was attempted in 100 consecutive patients. An IRB-approved review of our robot-assisted radical cystectomy database was conducted. Total operative (OR) time, cystectomy time, pelvic lymph node dissection (PLND) time, estimated blood loss (EBL), margin positivity, complications, and length of hospital stay were compared among patients divided into 4 cohorts of increasing surgical experience. Scattergrams and continuous curves were plotted to develop a robotic cystectomy learning curve.

RESULTS

Overall OR time decreased from 375 minutes in cohort 1 to 352 minutes in cohort 4, with less than 1% change in OR time after case 16. Time from incision to bladder extirpation decreased from 187 minutes in cohort one to 165 minutes in cohort 4. Time for PLND increased from 44 minutes in cohort 1 to 77 minutes in cohort 4. Lymph node yield increased from 14 nodes in cohort 1 to 23 nodes in cohort 4. Positive surgical margins decreased from 4 patients in cohort 1 to 0 patient in cohort 4. The complication rate had no change from 9 patients in cohort 1 to 9 patients in cohort 4.

CONCLUSION

Operative results and oncologic outcomes for robot-assisted radical cystectomy constantly improve as the technique evolves.

Positive Surgical Margins in Robotic-Assisted Radical Prostatectomy: Impact of Learning Curve on Oncologic Outcomes

OBJECTIVE

The presence of positive surgical margins following radical prostatectomy is a known risk factor for disease recurrence and may lead to adjuvant treatment. Our goal was to assess the incidence of positive surgical margins in our series of robotic-assisted radical prostatectomy (RARP) and its relationship to our learning curve.

METHODS

Between February 2003 and August 2005, 140 patients underwent RARP by the same surgical team at our institution. The records of our first 100 consecutive RARPs were retrospectively reviewed. The patients were divided into three groups based on the time of surgery: group I included the first 33 cases; group II included the second 33 cases; and group III comprised the last 34 cases. We compared the incidence and location of positive surgical margins among the groups. Additional variables evaluated included the patient's prostate-specific antigen (PSA) level, preoperative/postoperative Gleason score, clinical/pathologic stage, and pathologic tumour volume.

RESULTS

The positive margin rates were 45.4%, 21.2%, and 11.7% for groups I, II, and III, respectively. The difference in positive margin rates in the three groups was statistically significant (p=0.0053). Positive margin rates declined specifically at the apex and bladder neck when comparing the first 33 patients to the last 34 patients. Patient demographics and preoperative staging variables were comparable among all three groups, with no statistically significant differences among them.

CONCLUSIONS

This study illustrates that experience gained with time led to a decrease in the incidence of positive surgical margins. We do not feel that a selection bias affected our results because clinical and pathologic staging was evenly distributed within the three study groups. A steady reduction in positive surgical margin rates demonstrates a learning curve, of approximately 30 patients, associated with RARP, and suggests that oncologic outcome is affected by the experience of the robotic surgeon.

Laparoscopic Radical Prostatectomy: Impact of Modified Apical and Posterolateral Dissection In Reduction of Positive Surgical Margins in Patients with Clinical Stage T2 Prostate Cancer and High Risk of Extracapsular Extension

PURPOSE

To determine whether modifications of extraperitoneal endoscopic radical prostatectomy (EERP) reduce the rate of a positive surgical margin (PSM) in men with clinical stage T(2) prostate cancer and a high risk of extracapsular extension.

PATIENTS AND METHODS

A consecutive series of 182 men with stage cT(2) tumors and a high risk of extracapsular extension underwent EERP by a single surgeon (VP). The patients were divided into two groups: 71 patients who underwent a standard EERP (group 1) and 111 patients who underwent EERP with the modified technique (group 2). The basic principles of the modified technique are more thorough and wider resection of the posterolateral prostatic pedicles and extensive excision of periprostatic soft tissue at the apex, which results in better mobilization and exposure of the apex before the urethral transection. Differences in PSM rates were analyzed statistically.

RESULTS

No significant differences were found between the two groups regarding the clinical and pathologic findings (P > 0.05). The rate of PSM was 28% in group 1 and 10% in group 2 (P < 0.001). Group 2 was less than one third as likely to have PSM as group 2 (odds ratio 2.9; 95% confidence interval 1.6, 3.9). The strongest (P < 0.0001) independent predictors of PSM were the surgical technique, the presence of extracapsular disease, and the volume of the cancer. Preservation of the neurovascular bundles had no impact on margin status (P = 0.93). Functional outcomes and complication rates were not adversely affected by these modifications.

CONCLUSION

The modified dissection in EERP significantly reduces the rate of PSM in patients with stage cT(2) prostate cancer and a high risk of extracapsular extension.

Laparoscopic Radical Prostatectomy: A Critical Analysis of Surgical Quality

OBJECTIVE

To review the literature and answer the question of whether the laparoscopic approach meets the quality standards.

METHODS

We conducted an extensive Medline literature search. The articles obtained and the experience at Memorial Sloan-Kettering Cancer Center were used for interpretation and critical analysis of results. Long-term quality indicators are oncologic efficacy, potency rate, and continence rate. Short-term quality indicators are blood loss and transfusion rate, hospital stay, postoperative recovery, and rate and severity of complications.

RESULTS

Long-term quality indicators. Oncologic efficacy. Despite recent evidence that pelvic lymph node dissection (PLND) at radical prostatectomy may be necessary to detect occult positive lymph nodes, and that extended node dissection may also have a positive impact on disease-free survival, PLND is rarely performed during laparoscopic radical prostatectomy (LRP), which may have a negative impact on the long-term recurrence-free probability. Positive margins rates range from 11% to 26%, ranging from 6% to 8% for organ-confined disease and from 35% to 60% in those with extraprostatic extension. Most of these data include the first patients operated on when the technique of LRP was in early development. These rates seem high as compared to the contemporary data achieved in retropubic radical prostatectomy. Short-term biochemical recurrence rate have been published by only two centers and generalization to the whole laparoscopic patients and to long-term results are at present time hazardous. Functional outcome. Given the complexity of measuring, interpreting, and reporting continence and erectile dysfunction, the available results after LRP do not allow drawing any conclusion. Furthermore, the number of patients on whom results are reported is disproportionately low in relation to the large LRP experience accumulated so far. Short-term quality indicators. Assessment of LRP equanimity includes factors such as blood loss, transfusion rates, hospital stay, duration of catheterization, and complication profile. All the reports are concordant and demonstrate a benefit for the laparoscopic approach. However, no prospective and parallel studies compare the respective advantages of LRP and radical retropubic prostatectomy in reference centers.

CONCLUSIONS

In a review of the published literature results of LRP, there is not enough evidence to answer the question of whether the laparoscopic approach meets the quality standards. The available biochemical recurrence information is promising but limited to the short-term and the experience of two centers only. The question of omitting the PLND or performing a limited one in high-risk patients needs to be answered. The functional results analyses suffer from a lack of uniformity in methodology, a limited follow-up, and a disproportionately small number of patients in relation to the accumulated experience. Future reports of the post-learning phase era are dramatically needed.

Modular Training for Residents with no Prior Experience with Open Pelvic Surgery in Endoscopic Extraperitoneal Radical Prostatectomy

PURPOSE

To establish a teaching program for the performance of endoscopic extraperitoneal radical prostatectomy (EERPE) that would ascertain the safe and efficacious training of residents with no previous experience with open pelvic surgery.

MATERIALS AND METHODS

The technique of EERPE was divided in 12 segments with 5 levels of difficulty. We thus designed a training program, where the resident learned the procedure in a mentor-defined schedule. During each educational EERPE, the trainee only performed the operative steps corresponding to his acquired skill level. The mentor performed the remaining parts of the EERPE, with the trainee assisting. The first 50 and consequent 100 cases performed by the residents were compared to the first 50 and last 100 cases (cases 521-621) performed by the mentor.

RESULTS

Two residents with no prior experience with open pelvic surgery participated in the study, and required 43 and 38 procedures respectively, until they were considered to be competent. The initial 50 procedures performed completely independently by the residents had mean operative times of 176 and 173 minutes. There were 2 intraoperative rectal injuries (one patient developed recto-urethral fistula), and 1 hemorrhage, and 1 lymphocele, postoperatively. The positive margin rate for pT2 disease was 14.3 and 11.5%, and for pT3 tumors 38.8 and 29.1%, respectively. After an additional 100 procedures operated by the same residents, mean operative times were 142 and 146 minutes. There was one patient who needed a transfusion. Postoperative complications requiring re-intervention were 1 hemorrhage, 2 anastomotic leakages and 4 symptomatic lymphoceles. The positive margin rate for pT2 disease was 12.8% and 6.5%, and for pT3 tumors 33.3% and 26.3% respectively. No statistical significant differences were observed when comparing with the mentors cases.

CONCLUSION

We have showed that residents with no prior experience in open surgery of the pelvis can adhere to the modular training scheme and successfully perform the EERPE procedure with similar risk of complications compared to the tutor.

Modular surgical training for endoscopic extraperitoneal radical prostatectomy

OBJECTIVE

To develop a modular training scheme which enabled the use of individual steps of laparoscopic radical prostatectomy (RP) for teaching and training surgeons with varied experience, including residents with no experience in open RP, as in extending laparoscopic surgery to more complex operations like RP, the proper training of urologists is crucial.

SUBJECTS AND METHODS

The technique of endoscopic extraperitoneal RP (EERP) was divided into 12 individual steps of differing complexity. The levels of difficulty were called "modules" and graded according to their requisite skills from module 1 (lowest level of difficulty) to module 5 (highest level). Based on this modular system we established a training programme whereby the trainee learns the procedure in a mentor-initiated schedule. During each training operation the trainee only performs the modules (steps) of the operation, which correspond with his or her actual skill level. The mentor performs all the other steps, with the trainee assisting. Four trainees with different surgical experience participated in the study.

RESULTS

After a phase of assisting and camera holding during EERP, the trainees entered the modular training programme and required 32-43 procedures until they were considered to be competent. An analysis of the first 25-50 procedures done independently by the trainee showed mean operative times of 176-193 min and a transfusion rate of 1.3%. Complications during and after EERP requiring re-intervention were one each of recto-urethral fistula, haemorrhage, symptomatic lymphocele and anastomotic leak. The positive margin rate for pT2 disease was 12.2% and for pT3 tumours 37%.

CONCLUSION

The modular concept for teaching EERP is an attractive concept, which overcomes many of the problems involved in complex laparoscopic procedures. Based on a highly standardized technique, this concept offers a short learning curve; it enables training on different sites in cooperation with a high-volume centre, and it makes it possible to start with this complex procedure as a beginner or with no experience in open RP.

[Prognostic implications of positive margins in radical prostatectomy specimens]

To evaluate the histopathologic implication of positive margins of prostatectomy specimens in the biochemical recurrence.

MATERIAL AND METHODS

The study group consisted of 290 patients with clinically localized prostate cancer who were treated by radical retropubic prostatectomy. Patients with neoadjuvant hormonal therapy and positive lymph nodes were excluded. The mean age at the time of surgery was 63 years (range 47-73); 166 (57.2%) patients were T1c and 124 (42.8%) T2; the average time of folow-up was of 4 years (range 1-12). Positive surgical margins were defined as the presence of cancer cells at the surface inked of prostatectomy specimens. They were classified as: Margin for capsular incision (without extraprostatic extension evidence)/ margin for extraprostatic extension, margin with smooth rounded surface/margin with irregular surface, margin < or = 4 mm/margin > 4 mm, unifocal margin/multifocal margin. We define biochemical recurrence if the PSA exceeds 0.20 ng/ml in two consecutive determinations.

RESULTS

The overall rate of positive margins was 65/290 (22.4%). The 5-year survival free of biochemical recurrence was as follows: Negative margins 71% vs positive margins 44% (p < 0.001); positive margins for capsular incision 84% vs positive margins for extraprostatic extension 33% (p < 0.01); positive margins with smooth rounded surface 58% vs positive margins with irregular surface 26% (p < 0.01); positive margins < or = 4 mm 57% vs positive margins > 4 mm 32% (p < 0.05); unifocal margins 53% vs multifocal margins 0% (p < 0.01). The multivariate analysis revealed that preoperative PSA, Gleason score and pathological classification were the best predictors of biochemical recurrence.

CONCLUSIONS

Two groups are established of positive margin. The first group with high probability of biochemical recurrence: margin for extraprostatic. The second group with less probability of biochemical recurrence: margin for capsular incision, margin with smooth rounded surface, margin < or = 4 mm and unifocal margin.