Learning Curve of Laparoscopic Radical Prostatectomy in a University Teaching Hospital: Experience after the First 600 Cases

european urology supplements 5 (2006) 914–924

available at www.sciencedirect.com journal homepage: www.europeanurology.com

Learning Curve of Laparoscopic Radical Prostatectomy in a University Teaching Hospital: Experience after the First 600 Cases Luis Martı´nez-Pin˜eiro *, Felipe Ca´ceres, Carlos Sa´nchez, Angel Tabernero, Jose´ R. Cansino, Sergio Alonso, Jesu´s Cisneros, Jesu´s J. de la Pen˜a Urology Department, La Paz University Hospital, Madrid, Spain

Article info

Abstract

Keywords: Laparoscopy Learning curve Prostate cancer Radical prostatectomy

Objectives: To review features of initial and subsequent learning curves of laparoscopic radical prostatectomy (LRP). Methods: A total of 604 patients underwent LRP. Two surgeons started the programme. After the completion of the first 103 cases, three generations of surgeons entered the programme stepwise. Thirty-four patients were operated by four different surgeons, with limited laparoscopic experience, and were considered as a single, separate group for analysis. Patient data, operating data, intraoperative and postoperative complications, and positive surgical margins were analysed chronologically for the whole group and for each surgeon. Results: Mean operating time (201.5  68.0 min), estimated blood loss (346.7  351.7 ml), transfusion rate (11.3%), and intraoperative complications diminished with surgical experience and were less in the newer generations of surgeons ( p < 0.001). However, postoperative complications, prolonged hospital stay, and late removal of the drainage tube occurred significantly more frequently in surgeons who just performed LRP procedures occasionally. Postoperative pain decreased significantly with increasing surgical experience ( p < 0.05), but mean hospital stay (3.5 d) did not change in the whole series. Positive margin rate varied greatly among surgeons (overall positive margin rates pT2 = 19.2%, pT3 = 53.2%). There was a trend towards reduction of positive surgical margins in pT2 cases in most surgeons as experience grew. The combined retrograde-descending technique was associated with higher rates of positive margins at the apex (11.4% combined technique vs. 6.7% descending technique), whereas positive margins at the posterolateral region were more frequent in the descending technique (9% combined technique vs. 12.5% descending technique). Conclusions: Experience gained by the first generation of surgeons helped newer surgeons reduce the duration and morbidity of their corresponding learning curves.

Please visit www.eu-acme.org/ europeanurology to read and answer questions on-line. The EU-ACME credits will then be attributed automatically.

# 2006 European Association of Urology. Published by Elsevier B.V. All rights reserved. * Corresponding author. Pza. Conde Valle Suchil 17, 1B, 28015 Madrid, Spain. Tel. +34 91 727 73 05; Fax: +34 91 446 22 81. E-mail address: [email protected] (L. Martı´nez-Pin˜eiro). 1569-9056/$ – see front matter # 2006 European Association of Urology. Published by Elsevier B.V. All rights reserved.

doi:10.1016/j.eursup.2006.07.018

european urology supplements 5 (2006) 914–924

1.

Introduction

Laparoscopic radical prostatectomy (LRP) is becoming a standard surgical procedure in many centres worldwide. Early oncologic and functional results are similar to those obtained with open retropubic prostatectomy [1,2]. Most series have been reported by reference centres in which patients were operated on mainly by a single surgeon with vast experience in laparoscopic surgery [3–6]. We started our laparoscopic surgical programme in June 2002. We decided to make our learning curve in laparoscopy with radical prostatectomy because we had considerably more cases than nephrectomies, which allowed us to gain experience in a shorter period of time. Another reason for starting with radical prostatectomy was that although it is technically more difficult than laparoscopic nephrectomy, it is also less dangerous and has fewer life-threatening potential complications. Initially, two surgeons from our department started the programme with the transperitoneal radical prostatectomy after intensive training using the pelvic trainer and pig model and after staying 1 mo in a reference centre with a great deal of experience in LRP. After the performance of the first 100 cases another three surgeons from our department entered the programme stepwise. At the time of writing this report, five surgeons are routinely performing LRPs, and another four, including two residents, have done it only occasionally. We now summarise the features of the initial and subsequent learning curves. 2.

Patients and methods

Between 28 June 2002 and 28 April 2006 we have performed 604 LRP procedures. In four patients the surgery was reconverted to open surgery and they are not included in the statistical analysis. Patients were decodified and ordered chronologically from number 1 to number 600 for this review. Nine surgeons have participated in this laparoscopic programme. Surgeons 1 and 2 started the programme at the same time and have performed 168 and 144 procedures, respectively. In addition, each of them had to reconvert two cases. Surgeons 3, 4, and 5 did 119, 85, and 50 cases, respectively, and operated their first patients in place sequence 103, 173, and 236, respectively. The other 34 patients were operated by two staff members and two residents, with their first patient number 198 of the list. These four surgeons were considered as one single surgeon (surgeon number 6) for purposes of statistical analysis. The first two surgeons acted as assistants for each other during their first 20 cases. Thereafter, they were assisted by residents in their last 2 yr of training and by the newer generation of surgeons. The

915

latter were helped by the previous generation of surgeons during their first five cases and thereafter by the last-year residents. All patients were diagnosed previously with localised prostatic adenocarcinoma. All the surgeons used the descending transperitoneal surgical technique [7] except surgeon 1, who used the combined transperitoneal retrograde-descending technique or the Heilbronn technique [8] for the first 88 patients. Patients 89–122 were operated on with the same technique but with a modified apical dissection to diminish the positive margin rate at the apex. This technique consists in dissecting the neurovascular bundle off the apex before transecting the urethra. Patients 123–168 were operated on with the transperitoneal descending technique with the modified apical dissection. Urethrovesical anastomosis was performed with interrupted stitches by surgeon 1 following the Heilbronn technique [8]; the other surgeons used a running suture as described by Curto et al. [7]. Patients were treated following the clinical pathway of LRP of our department. Postoperative analgesia included administration of dipyrone 2.5 g intravenously every 6 h during the first 24 h and 1 g orally every 6 h thereafter until discharge. If further analgesia was requested by the patient (visual analogue scale [VAS] > 4), 10 mg ketorolac was administered intravenously every 6 h during the first 24 h and 10 mg orally every 6 h thereafter. On postoperative day 1 all patients were assisted in mobilisation and received a liquid diet; on postoperative day 2 they received a solid diet. All radical prostatectomy specimens were sectioned with whole-mount technique by specialised uropathologists. A positive surgical margin was defined as tumour cells in contact with the inked surface of the specimen, regardless of the length or size of the positive margin. We have reviewed the following data: patient age and body mass index (BMI), operating time (OR time), estimated blood loss, number of days with drainage, pain in the second postoperative day using a VAS with a score range from 0 to 10, hospital stay, presence or absence of urinary leak, days with postoperative bladder catheter, intraoperative complications, immediate postoperative complications (appearing within the first month after surgery), long-term complications (appearing after the first postoperative month), TNM staging (Union Internationale Contre le Cancer [UICC] 2002 classification), and surgical margin status. Postoperative erectile dysfunction and incontinence are not reviewed in this paper. To study the learning curve, all variables were calculated for the whole group of patients, for every 100 consecutive patients, for all the patients operated on by each single surgeon, and for every 25 consecutive patients operated on by each surgeon. The relative risk of positive margins was adjusted with a multivariate analysis. Statistical analysis was performed with the SPSS programme (Statistical Package for Social Sciences, version 11.01, Chicago, IL). ANOVA was used to compare nominal variables with continuous variables. The x2 and linear by linear association analysis was used to compare nominal variables among them. Cox multivariate regression analysis was used to correlate positive surgical margins with different risk factors. Data are expressed as mean  standard deviation and range unless otherwise specified.

916

3.

european urology supplements 5 (2006) 914–924

Results

Mean patient age was 62.3  29.1 yr (range: 48–76 yr) and mean BMI was 26.9  2.9 kg/m2 (range: 19.7– 38.8 kg/m2) with no statistical significant difference between patients operated on by different surgeons (ANOVA p > 0.05). The mean biopsy Gleason score was 6.26 (range: 5–9) and mean prostate volume was 39.6 cc (range: 10–125 cc) with no differences found among patients operated on by different surgeons (ANOVA p > 0.05). Open conversion was necessary only in patients 1, 6, 12, and 18. The respective reasons for conversion were long OR time and bladder injury (case 1, surgeon 1), inability to perform the vesicourethral anastomosis laparoscopically (case 6, surgeon 2), respiratory acidosis and subsequent atrial fibrillation in a patient with previous partial resection of one lung (case 12, surgeon 1), iliac artery plus iliac vein plus bowel perforation during the insertion of the second trocar (case 18, surgeon 2). Mean OR times of the whole series (201.5  68.0 min) and of each surgeon are shown in Fig. 1 and Table 1. The OR time decreased significantly over time with surgical experience (ANOVA p < 0.001) and was statistically different among the different surgeons (ANOVA p < 0.001; Fig. 2). It took approximately 80–100 cases for the first two surgeons to reach a stable OR time, whereas only 50 cases for the second generation, 20 for the third generation, and 10 for the fourth generation. Surgeons considered as surgeon 6 are not included in this analysis. Lymphadenectomy was performed in 96 patients (16%). The number and relative percentage of lymphadenectomies performed by each surgeon in his personal series was as follows: surgeon 1, 42 cases (25%); surgeon 2, 43 cases (29.9%); surgeon 3, 2 cases (1.7%); surgeon 4, 3 cases (3.5%); surgeon 5, 5 cases (10%); surgeon 6, 1 case (2.9%). Mean estimated blood loss was 346.7  351.7 ml (range: 50–3500 ml). Estimated blood loss and the

Fig. 1 – Operating time of the whole series. Arrows point out when the different surgeons did their first case. Surgeon 6 comprises a group of four different surgeons performing laparoscopic radical prostatectomies only occasionally.

need for transfusion decreased significantly over time (ANOVA p < 0.001; Fig. 3). Intraoperative or postoperative transfusion was necessary in 11.7% of our 100 first patients (11.3% overall), whereas only 6% of the last 200 patients required transfusion. Patients were given transfusions if the haemoglobin level fell to <9 g/l or if the patient was symptomatic with haemoglobin values between 9 and 11 g/l. In 92% of the patients, the drain was removed during the first 3 d postoperatively, with no differences observed between the first 100 cases and the patients operated on thereafter (range: 89–98%; x2 p > 0.05). The criteria to remove the drain were when the daily volume drained was <60 ml and whenever there was no suspicion of urinary

Table 1 – Number of cases operated by each surgeon and mean operating time Surgeon 1 2 3 4 5 6

No. of cases 168 144 119 85 50 34

Mean OR time 238.6  65.2 169.2  72.7 186.9  60.2 184.9  43.3 194.7  35.6 253.8  58.4

(150–630) (75–580) (110–390) (90–300) (105–270) (120–420)

Last 50 cases 207.9  23.1 126.2  28.6 174.4  43.2 184.5  42.7 194.7  35.6

(155–255) (75–210) (120–300) (90–300) (105–270)

Right column shows the mean OR time of the last 50 patients operated by each surgeon. Surgeon 6 comprises four different surgeons with limited experience. OR time = operating time.

917

european urology supplements 5 (2006) 914–924

Fig. 3 – Percentage of patients who needed intraoperative or postoperative blood transfusion among the series. Interpolation line shows tendency.

Fig. 2 – Operating time of the different surgeons (interpolation line).

leakage. In patients operated by surgeons 2, 5, and 6, the drain was removed more frequently after the third postoperative day than in patients operated by surgeons 1, 3, and 4 (x2 p < 0.001). Major intraoperative complications were statistically more frequent during the first 200 cases (4.5%) than thereafter (1.25%; x2 p = 0.045), whereas immediate- and long-term postoperative complica-

tions did not decrease with the number of cases operated on (Table 2). Major complications during surgery (Fig. 4), in the immediate postoperative period, or in the long term occurred only with surgeons 1 and 2. Of the 13 rectal injuries, 11 were caused by surgeon 2 and 2 by surgeon 1. The group of surgeons number 6 who performed LRP only occasionally had significantly more minor

Table 2 – Complications related to surgical experience Complications

Cases

Total

1–100

101–200

201–300

301–400

401–500

501–600

Major intraoperative Iliac vessel injury Rectal injury Ileal injury Pneumothorax

1 4* – 1

– 3* – –

– 1 – –

– 1 – –

– 2* – –

– – 1 –

1* 11 1* 1

Minor intraoperative

7

3

–

2

1

5

18

Major immediate postoperative Haemorrhage requiring surgery Bowel injuries Pelvic abscess Deep vein thrombosis

2 – 1 1

1 1 – –

– – – –

1 1 – –

– 1 – –

– – – –

4* 3* 1 1

Minor immediate postoperative Ileus Urine collected by drain Other

5 2 3

2 1 –

3 1 –

– – –

5 3 1

1 5 2

16 12 1

Major long-term complications Pulmonary thromboembolism Cerebral haemorrhage

– –

– –

2 –

– 1

– –

– –

2 1

Minor long-term complications Trocar incisional hernia Urethrovesical anastomotic stricture Other

5 – 2

3 – –

7 – –

1 1 1

– – –

2 – 2

18 1 5

*

Major complications, surgery performed by the same surgeon.

918

european urology supplements 5 (2006) 914–924

Fig. 4 – Percentage of minor (Intra.Minor) and major intraoperative complications (Intra.Major) related to surgeon. Only surgeons 1 and 2 (S1, S2), who had the first learning curve, had major complications. The group of surgeons number 6, with limited laparoscopic experience, had significantly more minor complications.

complications than the second, third, and fourth generation of surgeons. Mean hospital stay was 3.5 d and did not change with growing experience. No statistical difference could be found between the first 20 and first 50 cases compared to the subsequent cases performed. However, prolonged hospital stay (>3 d) was more frequent in surgeons 2, 5, and 6 (x2 p < 0.001). Mean postoperative pain was rated as 2  1.5 (range: 0–8). The percentage of patients with pain score >3 diminished significantly with time (from 32.9% in the first 100 patients to 3.2% in the last 100 patients; linear by linear association p < 0.05), but no statistical significant difference was found among the different surgeons. Cystourethrographies were performed in 54 consecutive patients on postoperative day 7 once each

of the first two surgeons had completed their first 20 cases successfully. Twenty-eight patients (51%) showed no leak of contrast medium at the anastomotic site, 23 (43%) only a small leak, and 3 (5%) a large leak. After these results, we decided to leave the catheter for 2 weeks in all subsequent patients and withdraw it without previous cystourethrographies, unless the patient had persistent urine leak through the drainage during the postoperative period (Table 2). The mean preoperative serum prostate-specific antigen (PSA) concentration was 8.04  5.19 ng/ml (range: 0.83–48.7 ng/ml). Mean PSA values did not change significantly during the study period (ANOVA p > 0.05). However, the relative percentage of non–organ-confined cancer cases increased progressively and significantly over time from 24% in the first 100 cases to 37% in the last 100 cases (linear by linear association p = 0.044). cTNM, pTNM, biopsy Gleason score, and positive surgical margins are summarised in Tables 3–5. Table 4 correlates biopsy Gleason score, PSA density, and positive surgical margins. Positive surgical margin rates decreased significantly from cases 101 to 400 (linear by linear association p = 0.047) when adjusted (Cox multivariate regression analysis) for different risk factors, such as preoperative serum PSA, BMI, patient age, digital rectal examination, percentage of positive biopsy cores, absolute number of positive biopsy cores, Gleason score of biopsy, preoperative erectile function, neurovascular bundle preservation, and surgeon (Fig. 5). Most surgeons showed a reduction of the positive margin rate over time in pT2 cases except surgeon 3, who had a persistent and continuous increase along his series (ANOVA

Table 3 – Relationship between T category, positive surgical margins, and pT category T category T1 T2–3

No.

Positive margins

pT0–2

pT3–4

460 (76.7%) 140 (23.3%)

123 (26.7%) 53 (37.8%)

348 (75.6%) 75 (53.6%)

112 (24.4%) 65 (46.4%)

Table 4 – Relationship between biopsy Gleason score, PSA density, and positive surgical margins PSA density

Biopsy Gleason score 6

7

8

<0.15 0.15–0.25 >0.25

14.9% (27/181) 24% (36/150) 34.5% (39/113)

17.6% (6/34) 42.9% (18/42) 64.8% (35/54)

40% (2/5) 40% (2/5) 77.7% (21/27)

Total

22.9% (102/445)

45.4% (59/130)

60% (15/25)

PSA = prostate-specific antigen.

european urology supplements 5 (2006) 914–924

919

Table 5 – Relationship between pT category and positive surgical margins stratified per surgeon Surgeon

pT2a-c

pT3a-b

pT4

1 2 3 4 5 6

23% (26/113) 10% (11/110) 24.4% (21/86) 17.9% (10/56) 26.5% (9/34) 18.1% (4/22)

57.7% (30/52) 45.5% (15/33) 66.7% (20/30) 41.4% (12/29) 50% (8/16) 53.8% (7/13)

0 100% (2/2) 0 0

Total

19.2% (81/421)

53.2% (92/173)

75% (3/4)

50% (1/2)

Two pT0 cases are not included.

p = 0.000; Fig. 6). Positive margins in pT3–4 cases did not change significantly with the surgeon’s experience (Fig. 7). Surgeon 1 changed the surgical technique over time. He performed the combined retrogradedescending technique (Heilbronn technique) during the first 122 cases and a pure descending technique in cases 123–168. During his first 88 cases the positive margin rate was 36.1% (22 of 61) in pT2 and 59.3% (16 of 27) in pT3 cases. From cases 89 to 122 he modified the apical dissection and instead of cutting the urethra before dissecting the neurovascular bundles off the prostate, he transected it only once the neurovascular bundles had been completely separated off the prostatic apex. Margins with this modified dissection went down to 4.3% (1 of 23) in pT2 (x2 p = 0.004) and 45.5% (5 of 11) in pT3 cases (x2 p = 0.43; Figs. 6 and 7). Cases operated by this surgeon with the descending technique and using the modified apical dissection had a positive margin rate of 10% (3 of 30) in pT2 (x2 p < 0.009 with respect to initial apical dissection technique) and 68.8% (11 of 16) in pT3 cases (x2 p > 0.05 with respect to previous cases). The descending technique was substantially not modified by the rest of the surgeons during the entire study period. Location of margins and evolution with the number of cases operated on are shown in Table 6 and Fig. 8. Posterolateral and apical margins were the most frequent. Although there was a tendency to have fewer isolated posterolateral positive margins and more isolated apical margins with time, during the last 100 cases the tendency changed completely. When analysing the locations of margins in cases done by surgeon 1, who changed the surgical technique with time, the relative percentage of isolated positive surgical margins at the posterolateral aspect of the prostate increased significantly (x2 p < 0.05) with the descending technique with respect to the retrograde technique (from 25% [11 of 44] to 42.8% [6 of 14]), whereas the relative percentage of positive apical margins remained

Fig. 5 – Percentage of positive surgical margins according to pT category and number of cases. Coloured numbers in the graph represent the percentage of cases with unilateral or bilateral preservation of neurovascular bundles for each group of patients.

stable regardless of the surgical technique used (Fig. 9). Overall, the combined retrograde-descending technique had a 11.4% (14 of 122) rate of positive margins at the apex versus 6.7% (32 of 478) for the descending technique, whereas positive margins at the posterolateral region were found in 9% (11 of 122) with the combined technique versus 12.5% (60 of 478) with the descending technique. The isolated surgical margin rate with the modified dissection of the apex using the combined technique was 5.8% (2 of 34) which compares favourably with the 6.7% using the descending technique.

4.

Discussion

We have reviewed our experience with LRP. Our centre is a university teaching hospital with a

Fig. 6 – Percentage of positive surgical margins in pT2 cases according to each surgeon and the number of cases operated consecutively by each of them.

920

european urology supplements 5 (2006) 914–924

Fig. 7 – Percentage of positive surgical margins in pT3–4 cases according to each surgeon and the number of cases operated consecutively by each of them.

resident training programme. We previously had almost no experience in laparoscopy. We had performed only a few cases of pelvic lymphadenectomy and lymphocele marsupialisation after renal transplantation in the early 1990s. In December 2001, L.M.-P. watched a live LRP procedure performed by Dr R. Gaston and was immediately convinced that the laparoscopic technique offered a much better view of the surgical anatomy than the open technique. After intensive training with the pelvic trainer and pig model and after staying 1 mo at a reference centre along with another surgeon from our department, we started the laparoscopic programme and performed the first LRP in June 2002. Between June 2002 and April 2006 we did 604 cases. We had four open conversions (0.66%), which occurred during the first 20 cases. This percentage of conversion is similar to the early series of LRPs reported by Rassweiler et al. [8] and Guillonneau et al. [9]. The OR time of the first cases was very high because we had no previous laparoscopic experience and we did not have the possibility of having a Spanish mentor. LRP was being started in very few centres in Spain at that time and nobody in our country had enough

experience to act as a mentor. The two first surgeons had to endure the initial learning curve and then after completion of the first 103 cases the newer generations of surgeons started their first cases. Mean OR time, estimated blood loss, transfusion rate, and intraoperative complications diminished with surgical experience and were fewer in the newer generations of laparoscopic surgeons (Figs. 1–4). Transfusion rate was just 6% during the last 200 cases. Similar findings have been reported by other centers [3,4,10–14]. Although OR time varied among the different surgeons depending on surgical technique used and personal abilities, there was a tendency for the learning curve to become shorter in the newer generation of surgeons (Fig. 2). It took approximately 80–100 cases for the first two surgeons to reach a stable OR time, whereas only 50 cases for the second generation, 20 for the third generation, and 10 for the fourth generation (Fig. 2). The second generation of surgeons started their first cases once the two first surgeons had each completed 50 surgeries. This means that there were three surgeons at a certain period of time who were improving the surgical technique at the same time and reducing the OR time simultaneously, which can be clearly seen in Fig. 2. The third and fourth generations started their first cases once the first generation had almost stabilised the OR time. It took the last generation of surgeons just 10–20 cases to stabilise the OR time. They acted as first assistants of the first two generations and not only learned different ways of doing the same operation, but learned from the errors and pitfalls of the previous surgeons. The four surgeons grouped as surgeon 6, who performed the surgery only occasionally, showed a significantly higher mean surgical time with no tendency to reduce after the initial cases. This fact, together with a higher rate of postoperative complications and longer hospital stay and drain removal, demonstrates that sporadic participation in a laparoscopic programme is not the way to go and

Table 6 – Location of positive surgical margins stratified per surgical technique Location of positive margins

Combined (n)

Descending (n)

Total

Posterolateral Apical Combined-multiple Anterior Bladder neck Seminal vesicle

9% (11) 11.4% (14) 12.3% (15) 4.1% (5) 0.8% (1) –

12.5% 6.7% 4.1% 1.2% 2.1% 0.4%

(60) (32) (20) (6) (10) (2)

40.3% (71) 26.1% (46) 19.8% (35) 6.2% (11) 6.2% (11) 1.1%(2)

Total

37.7% (46/122)

27.1% (130/478)

29.3% (176)

european urology supplements 5 (2006) 914–924

Fig. 8 – Location of single and combined positive surgical margins. Relative percentage among patients with positive margins. Posterolat. = posterolateral; bladd. = bladder.

requires a real commitment of the surgeon to act as an assistant for a long period of time before performing the surgical procedure himself. Lymphadenectomy was performed almost exclusively by the surgeons with the most experience, which may reflect a higher technical laparoscopic ability. Personal decisions and criteria for indicating the lymph node dissection may have played a role also. If we look at the major complications (Table 2 and Fig. 4), they appeared only in the first learning curve and were significantly more frequent in one of the two surgeons who started the laparoscopic programme. Curiously, this surgeon (number 2) was the fastest of the whole team, a fact that could have played a role in a poorer haemostasis (four patients required reintervention due to postoperative bleeding) and a poorer vision during surgery, making involuntary bowel injuries more frequent. On the other hand, this surgeon had the lowest margin rate, which is probably related to a more radical surgical technique. This might be also the reason for the higher percentage of rectal injuries that he presented (11 of 13 of the whole series) because rectal lesions are more frequent when the dissection of the pedicles and posterior plane is carried out more distant from the prostate [15]. Late removal of the surgical drain and prolonged hospital stay was usually related to urinary leakage, postoperative haemorrhage, or bowel lesion. Urine extravasation occurred in 1–5% (mean 2%) of the patients and was present uniformly along the whole series (Table 2). A similar percentage of urine extravasation has been described by the German Laparoscopic Working Group [16]. Mean hospital stay was 3.5 d and did not change significantly during the whole study period. In our

921

setting the shortest possible hospital stay was 2 d. Therefore, it is very difficult to shorten the mean stay of the whole series. Minor postoperative complications, which could not be reduced significantly with time and happened to all the surgeons, increased the mean hospital stay uniformly along the study period. Therefore, the mean hospital stay did not change along the initial learning curve. Also no statistical difference in hospital stay was found between the first 20 patients and the rest. Similar findings have been reported by Fabrizio et al. [12]. Postoperative pain could be reduced with surgical experience. A total of 32.9% of the first 100 patients operated by the first generation of surgeons had pain scores >3, whereas only 3.2% had such high scores among the last 100 patients. This is probably due to better surgical technique with fewer tractions and more precise dissection, together with a reduction of OR time, which has been shown to be related to decreased postoperative pain [17]. One of the areas in which we awaited a major impact associated with increased surgical experience was the rate of positive surgical margins. Our global positive margin rate was 19.1% for pT2 cases and 53.2% for pT3 cases, which is somewhat higher than that reported in the literature by most authors [1,2,18–21]. Differences in the positive surgical margin rates reported in the literature can be due to differences in the surgical technique or differences in the processing of the prostatic specimen and evaluation among different pathology laboratories. In our hospital we have two specialised uropathologists, who section and study the prostate with the whole-mount technique and are very sensitive in finding positive surgical margins. In pT2 cases, three of the five surgeons showed a

Fig. 9 – Location of single and combined positive surgical margins of surgeon 1. Relative percentage among patients with positive margins. Patients 1–122 were operated with the combined retrograde-descending technique and patients 123–168 with the descending technique. The technique of apical dissection was modified after patient 88. Posterolat. = posterolateral.

922

european urology supplements 5 (2006) 914–924

tendency towards the reduction of positive margins (Fig. 6) and only two of them (surgeons 2 and 5) had a constant increase with time. Surgical dissection of the neurovascular bundles by these two surgeons is carried along the intrafascial and interfascial plane very frequently, which might explain the higher rate of positive margins. In pT3–4 cases the number of positive margins was not influenced by surgical experience and remained in the range of 30–60% along the series without a clear tendency to diminish in any surgeon but one (Fig. 7). Patients with higher Gleason scores and higher serum PSA values, in which a pT3 category is suspected, therefore would be ideal candidates for a surgeon to start a learning curve. In this group of patients the margin rate seems less influenced by the experience of the surgeon and neurovascular bundle preservation is not indicated, making the surgery less demanding. Furthermore, taking into account the relationship of positive surgical margins, PSA density, and biopsy Gleason score reflected in Table 4, a further selection of patients can be performed in which a wide resection of the neurovascular bundles and periprostatic tissue would be indicated to avoid positive margins. Surgeon 3 had an initial dramatic decrease of positive margin rate in the first 25 cases, from 100% to 30%, but later when he gained further experience the positive margin rate increased again spectacularly, probably because this surgeon used the intrafascial and interfascial plane of dissection more frequently, as explained, to try to preserve sexual function in as many patients as possible. This high rate of positive margins during the last cases of this surgeon together with a higher rate of positive margins in the other surgeons also translates into a tendency towards higher positive margins for the whole series during the last 300 patients (Fig. 5). This is one of the reasons patients 100–300 had the lowest rate of positive margins. Regarding the location of positive margins (Fig. 8 and Table 6) we see that the most common locations are in the posterolateral and apical regions. Anterior margins seem to be stable with time, remaining <10% (relative percentage regarding absolute number of margins). We had an increase of margins at the bladder neck with time, reaching a relative percentage of 10%, which might be explained by two facts: (1) the significant increase of non–organconfined cancers that we had with time (from 24% in the first 100 cases to 37% in the last 100 cases) and (2) the tendency of the whole team to preserve the bladder neck to facilitate the fashioning of a watertight urethrovesical anastomosis. The performance of intraoperative frozen sections can help reduce the

rate of positive margins at the apex, as demonstrated by Dillenburg et al., and deserves to be used whenever there is a doubt of a positive apical margin after transecting the urethra, but it seems to be of no help reducing the positive margin rate at the bladder neck [22]. Surgeon 1 changed his surgical technique from a combined retrograde-descending technique (Heilbronn technique) performed in his first 122 cases to a pure descending technique performed in cases 123–168. Furthermore, after the first 88 cases he also modified the apical dissection technique, transecting the urethra only after sectioning the Walsh pillars and peeling the neurovascular bundles away from the prostatic apex or cutting them in case of no neurovascular preservation. This change was performed due to the high number of isolated positive margins at the apex that he presented at the beginning of his personal series (Figs. 6 and 9). With the classical retrograde technique the first manoeuvre after transecting the Santorini plexus is cutting the anterior urethral wall and generating cephalic traction with the bladder catheter, as is done in open radical prostatectomy, to expose the posterior aspect of the urethra. The traction of the catheter probably deforms the apex and makes the surgeon follow an incorrect plane of dissection, leaving prostatic parenchyma attached to the urethra when sectioning the lateral and posterior aspects of the urethra. The change in the apical dissection technique produced a dramatic decrease of positive margins from 43.1% to 17.6%, decreasing the absolute number of margins at the apex (Fig. 9). The same surgeon increased his positive margin rate to 30.4% during the next 46 cases performed with the descending technique, due to a relative increase of margins at the posterolateral aspect of the prostate. This fact might be attributed to the learning curve of this technique. Preservation of the neurovascular bundles with this technique requires the dissection to be carried along very close to the prostatic surface at the prostatic pedicles. This manoeuvre facilitates entering the interfascial plane of dissection that allows a complete preservation of the neurovascular bundles, but probably increases the risk of positive margins at this site.

5.

Conclusions

Experience gained by the first generations of surgeons helped newer generations of surgeons reduce the duration and morbidity of their corresponding learning curves.

european urology supplements 5 (2006) 914–924

Complications were significantly more frequent in surgeons who just performed LPR procedures occasionally, which indicates that sporadic participation in a laparoscopic programme is not the way to go and requires a real commitment of the surgeon to act as an assistant for a long period of time before performing the surgical procedure himself. Patients with higher Gleason scores and higher serum PSA values, in which a pT3 category is suspected, are the ideal candidates on whom a surgeon should start a learning curve. In this group of patients the margin rate seems less influenced by the experience of the surgeon and neurovascular bundle preservation is not indicated, making the surgery less demanding. The descending technique is associated with a greater rate of isolated positive surgical margins at the posterolateral aspect of the prostate (12.5%) compared to the combined retrograde-descending technique (9%). On the other hand, the combined technique has a higher rate of isolated positive margins at the apex (11.4% vs. 6.7%). To avoid positive surgical margins at the apex with the combined retrograde-descending technique, the urethra should be cut only after sectioning the Walsh pillars and peeling the neurovascular bundles away from the prostatic apex or cutting them in case of no neurovascular preservation (isolated apical margin rate = 5.8%).

Acknowledgements The authors thank Dr J. M. Alonso-Dorrego and Dr J. J. Lo´pez-Tello for their help in reviewing the charts of the operated patients. We also would like to thank the following members of the urology department of our hospital for referring their patients with localised prostate cancer: A. Aguilera, P. Ca´rcamo, E. Cuervo, M. J. Garcı´a-Matres, M. Hmeidan, J. Jime´nez, D. Lozano, S. Luengo, J. A. Moreno, J. Robles, F. Rodriguez Bethencourt, and J. P. San Milla´n. We also would like to thank our secretary Silvia for her administrative work.

[4]

[5] [6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17]

[18]

References [1] Rassweiler J, Hruza M, Teber D, Su L. Laparoscopic and robotic assisted radical prostatectomy—critical analysis of the results. Eur Urol 2006;49:612–24. [2] Toujier K, Guillonneau B. Laparoscopic radical prostatectomy: a critical analysis of surgical quality. Eur Urol 2006;49:625–32. [3] Frede T, Erdogru T, Zukosky D, Gulkesen H, Teber D, Rassweiler J. Comparison of training modalities for

[19]

[20]

923

performing laparoscopic radical prostatectomy: experience with 1,000 patients. J Urol 2005;174:673–8. Bollens R, Sandhu S, Roumeguere T, Quackels T, Schulman C. Laparoscopic radical prostatectomy: the learning curve. Curr Opin Urol 2005;15:79–82. Trabulsi EJ, Guillonneau B. Laparoscopic radical prostatectomy. J Urol 2005;173:1072–9. Guillonneau B, el-Fettouh H, Baumert H, et al. Laparoscopic radical prostatectomy: oncological evaluation after 1,000 cases at Montsouris Institute. J Urol 2003;169:1261–6. Curto F, Benijts J, Pansadoro A, et al. Nerve sparing laparoscopic radical prostatectomy: our technique. Eur Urol 2006;49:344–52. Rassweiler J, Sentker L, Seemann O, Hatzinger M, Stock C, Frede T. Heilbronn laparoscopic radical prostatectomy. Technique and results after 100 cases. Eur Urol 2001; 40:54–64. Guillonneau B, Rozet F, Cathelineau X, et al. Perioperative complications of laparoscopic radical prostatectomy: the Montsouris 3-year experience. J Urol 2002;167:51–6. Stolzenburg JU, Schwaibold H, Bhanot SM, et al. Modular surgical training for endoscopic extraperitoneal radical prostatectomy. BJU Int 2005;96:1022–7. Poulakis V, Dillenburg W, Moeckel M, et al. Laparoscopic radical prostatectomy: prospective evaluation of the learning curve. Eur Urol 2005;47:167–75. Fabrizio MD, Tuerk I, Schellhammer PF. Laparoscopic radical prostatectomy: decreasing the learning curve using a mentor initiated approach. J Urol 2003;169:2063–5. El-Feel A, Davis JW, Deger S, et al. Positive margins after laparoscopic radical prostatectomy: a prospective study of 100 cases performed by 4 different surgeons. Eur Urol 2003;43:622–6. Hoznek A, Salomon L, Olsson LE, et al. Laparoscopic radical prostatectomy. The Creteil experience. Eur Urol 2001;40:38–45. Martı´nez-Pin˜eiro L, Pe´rez-Chrzanowska H, Serra Gonza´lez J, de la Pen˜a JJ. Handling complications in laparoscopic radical prostatectomy. In: de la Rosette J, Gill I, editors. Laparoscopic urologic surgery in malignancies. Berlin: Springer; 2005. p. 185–200. Rassweiler J, Stolzenburg J, Sulser T, et al. Laparoscopic radical prostatectomy—the experience of the German Laparoscopic Working Group. Eur Urol 2006;49:113–9. Remzi M, Klingler HC, Tinzl MV, et al. Morbidity of laparoscopic extraperitoneal versus transperitoneal radical prostatectomy verus open retropubic radical prostatectomy. Eur Urol 2005;48:83–9, discussion 89. Rassweiler J, Schulze M, Teber D, et al. Laparoscopic radical prostatectomy with the Heilbronn technique: oncological results in the first 500 patients. J Urol 2005; 173:761–4. Stolzenburg JU, Rabenalt R, Do M, et al. Endoscopic extraperitoneal radical prostatectomy: oncological and functional results after 700 procedures. J Urol 2005;174: 1271–5. Hoznek A, Samadi DB, Salomon L, De La Taille A, Olsson LE, Abbou CC. Laparoscopic radical prostatectomy: published series. Curr Urol Rep 2002;3:152–8.

924

european urology supplements 5 (2006) 914–924

[21] Guazzoni G, Cestari A, Naspro R, et al. Intra- and perioperative outcomes comparing radical retropubic and laparoscopic radical prostatectomy: results from a prospective, randomised, single-surgeon study. Eur Urol 2006;50:98–104.

[22] Dillenburg W, Poulakis V, Witzsch U, et al. Laparoscopic radical prostatectomy: the value of intraoperative frozen sections. Eur Urol 2005;48:614–21.