Robot-Assisted Radical Prostatectomy in Low-Volume Regions: Should It Be Abandoned or Adopted? A Multi-Institutional Outcome Study

Abstract

Purpose:

To present multinational experience in robot-assisted radical prostatectomy (RARP) by fellowship-trained expertise in low-volume regions in Gulf Cooperation Council (GCC) countries and to compare the current results with global outcomes reported in recent meta-analyses.

Methods:

A retrospective review of prospectively collected data was performed for patients undergoing RARP for localized prostate cancer (PCa). Three fellowship-trained surgeons at four academic and referral centers in Saudi Arabia and Kuwait performed all procedures between February 2014 and December 2019. Data on demographics, perioperative characteristics, pathology, and adverse events were collected.

Results:

A total of 207 patients were included with a median (IQR) follow-up duration of 28 (15–38) months. The median prostate volume and prostate-specific antigen were 42 (32–53) g and 9.1 (5.8–14.1) ng/mL, respectively. While 65.2% of patients had a Gleason score ≥7, 20% had grade group 4 disease, and 7.8% had ≥cT3 disease. The mean ± SD operative time was 203 ± 52 minutes, and the mean estimated blood loss was 158 ± 107 mL. Only 4 (1.9%) patients received perioperative blood transfusions. Positive surgical margins were observed in 21.7% of patients, all of whom had ≥pT3 disease. There were 23 complications in 18 (8.7%) patients, including Clavien-Dindo grade III complications in 2.4%. At the 12-month follow-up, 35.8% of patients were potent, 94.6% were continent, and 9.2% had biochemical recurrence.

Conclusions:

The safety and efficacy of RARP by fellowship-trained expertise in GCC countries were well established. The outcomes seem promising and comparable to international centers and should improve with increasing case volume and fellowship-trained expertise.

Introduction

Prostate cancer (PCa) is the most common cancer in men, and it has high morbidity and mortality rates.¹ The emergence of surgical robots facilitates intracorporeal dissection and suturing due to the three-dimensionally magnified vision, depth perception, and EndoWrist technology. The robotic arms allow surgeons to perform more precise dissection, which leads to better preservation of vital structures, reduced positive surgical margins (PSMs), and better perioperative outcomes.²

With the advancement of surgical techniques, procedures performed using minimally invasive robotic technology have replaced many open surgical procedures. Despite its increasing costs, robot-assisted radical prostatectomy (RARP) has become the most commonly performed urologic robotic procedure, and it is almost regarded as the standard surgical approach for the treatment of localized PCa.³

Although comparable to laparoscopic radical prostatectomy in PSM rate compared to retropubic prostatectomy (RRP), RARP has the advantages of reduced blood loss, shorter hospital stay, and significantly lower perioperative complications, readmission, and reoperation rates.^3,4 Despite being ranked third among other malignancies between 1998 and 2012,⁵ the incidence and mortality rates of PCa in Middle Eastern countries are not as high as North America and Europe.

Twenty-four da Vinci^® robotic systems are installed in Gulf countries, including 14 (58.3%) in Saudi Arabia (Kingdom of Saudi Arabia, KSA) and two (8.3%) in Kuwait. However, the availability of surgical robots in the Middle East lacks appropriate marketing, which results in a scarcity of related research and publications and limits the characterization of robotic surgery trends in this area.⁶

Robotic surgery is becoming more popular in the Middle East, and many fellowship-trained surgeons are returning with expertise in robotic surgery to pave the way for this minimally invasive surgery to become the standard of care, especially for complex oncologic cases. Notably, most KSA respondents to an online survey felt that robotic training should be included in their career goals.⁷ Therefore, the current study presented the first multinational multicenter experience in RARP in the Middle East and compared the perioperative outcomes with international published data.

Methods

Study design

After obtaining institutional ethical approval, a retrospective review of prospectively collected data was performed for all patients undergoing RARP for localized PCa. Three fellowship-trained surgeons (R.A., D.R., and S.A.) at four different academic and referral centers in the KSA and Kuwait performed all procedures between February 2014 and December 2019, using the da Vinci surgical system (Intuitive Surgical, Inc., Sunnyvale, CA). All operable cases who presented with localized PCa underwent surgery, with no bias in the choice of smaller glands or lower prostate-specific antigen (PSA). Data analyses did not include the first cases performed by surgeons. Urethral catheters were removed between the 7th and 10th postoperative days unless there was urine leakage. Perioperative cystography was not routinely performed unless urine leakage was suspected intraoperatively or from the drain.

Data collection and outcomes

The perioperative data included operative time, estimated blood loss (EBL), transfusion rate, length of hospitalization, catheterization duration, and complications. The functional outcomes included potency and urinary continence at the 12-month follow-up, and the oncologic outcomes included the final pathologic stage and surgical margin. Follow-up was regularly performed after 8 weeks, every 3 months for the first 2 years, every 6 months for the subsequent 2 years, and yearly thereafter.

Surgeon's experience

The three surgeons completed their fellowships in high-volume oncology centers in the United States. R.A. did a high-volume robotic uro-oncology fellowship at the University of Southern California in Los Angeles mentored by pioneers in the field. S.A. did his Society of Urologic Oncology fellowship training at MD Anderson Cancer Center. Both surgeons had extensive training in advanced robotic urologic oncology during their fellowships. Their fellowship involvement in cases was similar and included at least 50% hands-on experience with independence in decision-making. D.R. did an Endourology fellowship in Eastern Virginia Medical School followed by a fellowship in Uro-oncology at Memorial Sloan Kettering Cancer Center. There was minimal robotic experience in 2002–2004, and all of his training was laparoscopic. All three surgeons are registered with intuitive as a robot-trained urologist.

Definitions

A PSM was defined by the presence of cancer in the inked margin. Extended lymph dissection was performed in high-risk patients, and other patients underwent standard lymphadenectomy. Biochemical recurrence (BCR) was defined as a PSA level >0.2 ng/mL on two consecutive samples in patients who had an undetectable PSA level at the 8th week postoperatively. Continence was defined as the use of 0 pads, and potency was defined as the ability to penetrate during sexual intercourse with or without oral phosphodiesterase-5 inhibitors (PDE5-I). Postoperative complications were graded according to the Clavien-Dindo classification system and grouped as minor (grades I and II) or major (grades III-V).⁸ The D'Amico Risk Classification for PCa⁹ assessed the 5-year risk of treatment failure based on clinical factors.

Data analysis

Data analyses were performed using the commercially available Statistical Package for Social Science for Windows (SPSS, Chicago IL), version 22. Descriptive data are presented as numbers and percentages for categorical variables and medians and interquartile ranges (IQRs) or means ± SD for continuous variables. Categorical variables were analyzed using Fisher's exact test, and the Mann–Whitney U test was used to analyze continuous variables. A two-tailed p-value of <0.05 indicated significant differences.

Results

A total of 207 patients diagnosed with prostatic adenocarcinoma were included in the data analyses. Table 1 summarizes the baseline demographics and clinical characteristics of the patients. The median (IQR) age was 64 (59–69) years, and the median prostate volume and PSA levels were 42 (32–53) g and 9.1 (5.8–14.1) ng/mL, respectively. While 65.2% of patients had a Gleason score ≥7, 20% had grade group 4 disease and 7.8% had ≥cT3 disease. D'Amico risk stratification showed 81.2% with an intermediate-to-high risk.

Table 1.

Preoperative Demographics and Clinical Characteristics (n = 207)

Parameter	Median (IQR)/Mean ± SD or No. (%)
Age (years)	64 (59–69)
Nationality
Gulf citizen	138 (67.0)
Non-Gulf citizen	69 (33.0)
Family history of cancer	29 (14.0)
History of TURP	7 (3.4)
Smoker (n = 176)
No	112 (63.6)
Yes	50 (28.4)
Ex-smoker	14 (8)
Comorbidities
DM	87 (42.0)
Hypertension	105 (50.7)
CVD	20 (9.7)
Others	66 (31.9)
SHIM score (n = 84)
≥ 22–25	38 (45.2)
8 − 21	22 (26.2)
≤ 7	24 (28.6)
Prostate size (mL)	42 (32–53)/48.3 ± 37.4
PSA (ng/mL)	9.1 (5.8–14.1)/12.6 ± 11.6
PIRADS	5 (4–5)/4.33 ± 0.97
D'Amico risk classification
Low	39 (18.9)
Intermediate	86 (41.5)
High	82 (39.6)
ASA score (n = 112)
ASA I	19 (17)
ASA II	84 (75)
ASA III	9 (8)
Clinical stage “cT”
cT1C	141 (68.1)
cT2	50 (24.1)
cT3	16 (7.8)
Biopsy Gleason score/GG
3 + 3/GG1	72 (34.8)
3 + 4/GG2	63 (30.4)
4 + 3/GG3	31 (15)
≥4 + 4/GG4/5	41 (19.8)

IQR = interquartile range; DM = diabetes mellitus; CVD = cardiovascular disease; TURP = transurethral resection of the prostate; PSA = prostate-specific antigen; GG = grade group; SHIM = sexual health inventory for men.

Perioperative data

The means ± SD operative time and EBL were 203 ± 52 minutes and 158 ± 107 mL, respectively. Only 4 (1.9%) patients received perioperative blood transfusions, with no conversions to open surgery. The mean catheterization time and hospital stay were 11.6 ± 5.3 and 4.46 ± 2.52 days, respectively (Table 2). Standard and extended lymphadenectomy were performed in 55.1% and 19.3% of patients, respectively. Unilateral and bilateral nerve-sparing procedures (NSP) were performed in 43% and 10.6% of patients, respectively.

Table 2.

Perioperative Data and Functional Outcomes of Patients

Parameter	Median (IQR)/Mean ± SD or No. (%)
Resident involvement	62/207 (30.0)
Operative time (min)	180 (180–240)/203 ± 52
EBL (mL)	100 (50–200)/158 ± 107
EBL <200 mL	77.8%
Perioperative transfusion	4 (1.9%)
Lymph node dissection
Not performed	53 (25.6)
Standard	114 (55.1)
Extended	40 (19.3)
Nerve sparing
Not performed	96 (46.4)
Bilateral	22 (10.6)
Unilateral	89 (43.0)
Hospital stay (days)	4 (3–5)/4.46 ± 2.52
Catheterization time (days)	9 (8–14)/11.6 ± 5.3
Postop. cystography	63/182 (34.6)
Postop. potency	39/109 (35.8)
Postop. urinary incontinence	66/148 (44.6)

SD = standard deviation; ASA = American Society of Anesthesiology; EBL = estimated blood loss; Postop = postoperative.

Pathologic outcomes

The median (IQR) prostate weight was 50 (40–62) g. pT3 was found in 41.1% of patients, including 9 (4.3%) patients with SVI. Diseases in grade groups 2 and ≥3 were detected in 45.9% and 36.2% of patients, respectively. PSM was observed in 21.7% of patients. All were found in patients with ≥pT3 disease, and 17.9% of patients had extracapsular extension (ECE) (Table 3).

Table 3.

Pathologic Data of the Robot-Assisted Radical Prostatectomy Patients (n = 207)

Parameter	Median (IQR) or No. (%)
Final prostate weight (g) (n = 180)	50 (40–62)
Total number of examined lymph nodes	8 (4–12)
Lymph node status
Negative	161 (77.8)
Positive	16 (7.7)
NA (X)	30 (14.5)
Margin status ECE & SVI
Overall PSM	45 (21.7)
ECE	37 (17.9)
SVI (uni/bilateral)	9 (4.3)
SVI (uni/bilateral)	(6/3) (2.9/1.4)
Peripheral nerve invasion	91 (44.0)
Lymphovascular invasion	19 (9.2)
Pathologic staging (pT)
pT2	122 (58.9)
pT3a	61 (29.5)
pT3b	24 (11.6)
Final Gleason score/GG
3 + 3/GG1	37 (17.9)
3 + 4/GG2	95 (45.9)
4 + 3/GG3	43 (20.8)
4 + 4/GG4	5 (2.4)
4 + 5/GG5	27 (13.0)
Postoperative PSA (ng/mL)
8 weeks after surgery	0.003 (0.0–0.035)
Latest follow-up	0.003 (0.0–0.079)
Salvage therapy
None	184 (88.9)
Radiotherapy or ADT	11 (5.3)
Combination therapy	12 (5.8)

IQR = interquartile range; PSM = positive surgical margin; PSA = prostate-specific antigen; ECE = extracapsular extension; SVI = seminal vesicle invasion; GG = grade group; ADT = androgen deprivation therapy.

Complications

There were 23 complications detected in 18 (8.7%) patients, including 18 minor and five grade III complications. Two complications were managed intraoperatively (a rectal injury and a left ureteral injury in two different patients), and three complications were diagnosed after three, seven, and 13 months, including one case of incisional hernia and two bladder neck contractures. Cystography was performed in 66 (34.6%) patients to exclude urinary leakage, which was detected in four patients and necessitated prolonged catheterization.

Functional outcomes

Of the 84 patients who were evaluated using the Sexual Health Inventory for Men (SHIM) questionnaire, 38 (45.2%) had a preoperative score ≥22 and underwent NSP. After 12 months, 35.8% of patients were potent with or without a PDE5-I. After 12 months, 94.6% of patients were continent, and most patients developed continence between the 8- and 12-week follow-up visits. The mean time to urinary continence recovery was 5.2 ± 4.2 months.

Biochemical recurrence

The postoperative PSA level never became undetectable (<0.1 ng/mL) in 13 (6.2%) patients: eight patients had pT3b disease, and five patients had pT3a disease. These patients were treated with androgen deprivation therapy (ADT) ± radiation therapy. After a median (IQR) follow-up of 28 (15–38) months, 19 (11.1%) patients had BCR, including 11/61 (18.0%) pT3a and 8/24 (33.7%) pT3b patients. Patients with pT3b disease and/or lymph node metastases were referred for adjuvant therapy before reaching a PSA level >0.2 ng/mL.

Perioperative, functional, and oncologic outcomes were comparable between the three surgeons (Table 4).

Table 4.

Perioperative, Functional, and Oncologic Outcomes of the Three Surgeons

Surgeon	R.A.	S.A.	D.R.	p-value
Cases	82 (39.6)	60 (29.0%)	65 (31.4)	NA
Perioperative
Mean prostate size/mL	55.0 ± 10.7	41.5 ± 9.4	43.9 ± 2.2	0.23
Mean PSA at diagnosis (ng/mL)	14.66 ± 1.33	7.9 ± 2.14	9.63 ± 0.73	0.11
Mean Operative time/min	246 ± 36	175 ± 42	218 ± 85	0.28
Mean EBL/mL	222 ± 27	116 ± 108	105 ± 13	0.09
Mean Hospital stay/day	3.2 ± 0.5	2.9 ± 1.2	2.7 ± 0.14	0.82
Final pathology Gleason score/GG
3 + 3/GG1	17 (20.7)	11 (18.3)	9 (13.8)	0.09
3 + 4/GG2	39 (47.6)	26 (43.3)	30 (46.2)
4 + 3/GG3	12 (14.6)	19 (31.7)	12 (18.5)
≥4 + 4/GG4/5	14 (17.1)	4 (6.7)	14 (21.5)
PSM	21 (25.6)	12 (20.0)	12 (18.4)	0.54
BCR at 12 months	9 (11.0)	6 (10.0)	4 (6.2)	0.58
Functional
Continence at 12 month	92.6	94.8	95.2	0.12
Potency at 12 month	35.8	81.7	40.0	0.06
Patients with adverse events	5 (6.1)	7 (11.7)	6 (9.2)	0.49

Data are presented in No (%) or mean ± SD.

PSM = positive surgical margin; BCR = biochemical recurrence; PSA = prostate-specific antigen; EBL = estimated blood loss; GG = grade group; NA = not applicable.

Discussion

Since its first approval in 2000, RARP has become the preferred minimally invasive procedure for the management of clinically localized PCa. Several technical modifications to RARP were reported, but no specific techniques demonstrated better improvements in functional outcomes.¹⁰ The current study presented the first multinational multicenter experience in RARP in the Middle East, considering the lack of characterization of robotic surgery trends in this area. Our perioperative outcomes were comparable to a meta-analysis that included 110 articles (Table 5), with a mean operative time of 152 minutes, a mean EBL of 166 mL, and a mean transfusion rate of 2%. The mean catheterization time and length of hospital stay were 6.3 and 1.9 days, respectively.¹¹

Table 5.

Comparison of the Current Series with Recently Published Meta-analyses

Parameter	Current	Meta-analyses	p-value
Mean operative time (min)	203 ± 52	264 ± 102^a	<0.001
Mean EBL (mL)	158 ± 107	287 ± 291^a	<0.001
Perioperative transfusion (%)	1.9	2.3^a	0.88
Mean hospital stay (d)	4.5 ± 2.5	2.2 ± 1.9^a	<0.001
PSM
Overall (%)	45 (21.7)	1098/4929^b (22.3)	0.19
≤pT2 (%)	0/122 (0.0)	314/2139^b (14.7)	<0.001
≥pT3 (%)	45/85 (52.9)	434/1049^b (41.4)	0.04
BCR at 12 months (%)	19/207 (9.2)	204/2766^b (7.4)	0.07
Continence rate at 12 months (%)	140/148 (94.6)	1845/2575^b (71.6)	<0.001
Potency rate at 12 months (%)	39/109 (35.8)	381/2599^b (14.6)	<0.001
Adverse events
Total (%)	18/207 (8.7)	81/602^b (13.5)	0.36
Major >GII (%)	5/207 (2.4)	11/335^b (3.3)	1.00

Davis et al.²⁴ (n = 27,348).

Cao et al.²⁵ (n = 4929).

PSM was detected in the 45 (21.7%) patients who had ≥pT3 disease, and none of our pT2 patients had a PSM, which is consistent with other reports.^12
–14 In a multi-institutional study involving 6000 patients, the overall PSM rate was 15.7%, and the PSMs for pT2 and pT3 disease were 9.4% and 37.2%, respectively.¹² Our higher overall PSM may be due to the inclusion of intermediate- and high-risk patients. A mean (range) overall PSM of 15% (6.5–32) was reported, with means of 9% (4–23) and 37% (29–50) in pT2 and pT3 cancer, respectively.¹⁵ The surgeon and tumor characteristics were the most relevant predictors of a PSM, which may further explain the higher PSM rate in our study in pT3 patients.

All of the cumulative analyses comparing RARP with RRP demonstrated comparable overall PSM rates (OR: 1.21 vs 1.12).¹⁵ Consistent with our data at high-volume centers, PSM was found in 192 (26.3%) patients, which was independently influenced by the percentage of biopsy-positive cores, ECE, SVI, and high-volume surgeons.¹⁶

We recorded an 8.7% complication rate, including 2.4% of grade III. Fuller and Pautler reported a total of 70 (23%) complications in 305 procedures, including 22 (7%) major complications.¹³ Data from 104 research articles highlighted the significantly higher rate of major complications with RRP than RARP (OR:2.14).¹⁷ In their meta-analysis, Novara et al. reported a mean complication rate of 9%,¹¹ which is consistent with our records.

The potency rate in the current study was 35.8% at 12 months, which is similar to a meta-analysis.¹⁸ One of the meta-analyses reported post-RARP potency rates that ranged from 54% to 90% and from 63% to 94% after 12 and 24 months, respectively, where the recovery of potency was significantly associated with age, baseline potency, comorbidity index, and NSP.¹⁹

Our urinary continence recovery rate at 12 months was 94.6%, where most patients regained continence at the 12-week visit, which is consistent with recently reported findings.^20,21 All of our patients were asked to perform Kegel exercises, which contribute to the earlier recovery of urinary continence.²² A meta-analysis of 51 articles reported a mean (range) urinary incontinence rate of 16% (4–31%) after 12 months using a no-pad definition, which was significantly associated with age, body mass index, comorbidity index, prostate volume, and voiding symptoms.²¹

Menon et al.²³ found actuarial BCR-free survival rates of 95%, 91%, 87%, and 81% at 1, 3, 5, and 7 years, respectively, with a median time to BCR of 20.4 months.²³ However, a published meta-analysis reported a 7-year BCR-free survival estimate of ∼80%.¹⁵ Our BCR was 9.2%, which is comparable to previously reported rates.^15,20,23

A comparison of our current results with a recently published large series is presented in Table 6. Our data reveal a significantly lower operative time and EBL, but a longer hospital stay because most of our patients were not willing to go home with a drain. The potency and continence rates were significantly better in the current cohort. The complication rate, BCR rate, and overall PSM rate were comparable. Despite the higher PSM rate in pT3 patients in the present study, none of our pT2 patients had a PSM. Leroy et al. found that fellowship-trained RARP surgeons had significantly lower PSM rates than surgeons who performed RRP (15% vs 34%) in their first 30 cases³¹ and exceeded surgeons who had previously performed more than 25 laparoscopic procedures in the PSM rate (24% vs 35%), especially at the prostate apex (8% vs 21%).³²

Table 6.

Oncologic and Functional Outcomes and Complications in Contemporary Robot-Assisted Radical Prostatectomy Series

Study	No pts	Overall PSM	PSM ≤PT2	PSM ≥pT3	Potency at 12 months	Continence at 12 months	BCR at 12 months	Overall AEs
Kaul et al.²⁶	154	6.4	4.6	NA	96	97	0	12
Di Pierro et al.²⁷	75	16.0	8.3	46.7	54.5	88.9	11.1	40
Al-Hathal and El-Hakim²⁸	250	30.0	25.7	43.3	85	92.3	4.2	12
Fuller and Pautler¹³	305	16.0	10.2	32.0	—	91.4	—	23
Park et al.²⁹	730	11.3	36.0	44.7	—	—	—	—
Ong et al.³⁰	885	22.8	8.0	48	81	72.9	12.2	—
Menon et al.²³	60	13.0	11.0	22.0	69.2	93.3	7.3	12
Current	207	21.7	0.0	52.9	35.8	94.6	9.2	8.7

NA = not applicable.

Building an effective robotic program in low-volume regions requires attention to many aspects, including economics, teaching, and education. Surgeons should have certified fellowship training in robotic surgery before clinical use. The presence of a robotic proctor initially helps in building team confidence and setting up basic institutional protocols. The subsequent increased volume will help shape the program with continued assessments of outcomes. For the program to be cost effective and adequately implemented, multiple specialties should be involved in the program. Having a designated robotic team of nursing staff, anesthetists, surgeons, and bedside assistants improves outcomes and saves case turnover time. Social media plays an important role in educating the society about this modality. Once established, the program should strive toward achieving certain set performance benchmarks without compromising patient safety, taking into account the quality, and not only the quantity, of the procedures performed. Data collection and analyses help in the analyses of progress, growth, and costs.

The major limitation of the present study is its retrospective nature. However, this limitation is the first multinational study of its kind, and all procedures were performed by fellowship-trained robotic urologists. Given that the volume of prostatectomy in the Middle East Arab countries is relatively low, the present outcomes may not be achieved by surgeons or hospitals with a lower volume, but they support regionalization and referral to fellowship-trained, high-volume centers.

Conclusion

The current cohort represents the first multicenter experience in RARP in the Middle Eastern region. The safety and efficacy of RARP in the present study were well established. The outcomes seem promising and comparable internationally published studies. With the increasing volume of cases and number of fellowship-trained surgeons in robotic uro-oncology, the outcomes should improve. This training is crucial to achieve adequate functional and oncologic outcomes with low rates of adverse events.

Footnotes

Acknowledgment

The corresponding author acknowledges Dr. Abdullah Alahmari, Dr. Ziad Alzahrani, and Dr. Rabea Akram from Department of Urology, King Abdulaziz University, Jeddah, Saudi Arabia, for their help in data collection.

Ethics

The present study involved human participants, and all procedures were performed in accordance with the Declaration of 1964 Helsinki and its later amendments.

Availability of Data and Material

According to Norwegian data legislation, the data of this study cannot be made generally available. Requests may be made to the corresponding author.

Authors' Contribution

R.A. contributed substantially to the study design, performed the surgery, data interpretation, drafting of the article and supervision of the entire study. S.A. contributed equally to the study design, performed the surgery, data interpretation, drafting of the article, and supervision of the entire study. M.M.A. collected the data and participated in drafting the article. M.F.A. collected the data and participated in drafting the article. S.S.A. collected the data and participated in drafting the article. A.M.N. participated in drafting the article and data analysis. A.A. collected the data and participated in drafting the article. S.Y. collected the data and participated in drafting the article. D.R. performed the surgery.

Author Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.

Abbreviations Used

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