World J Surg (2012) 36:2722–2729 DOI 10.1007/s00268-012-1728-4
Robotic versus Conventional Laparoscopic Surgery for Rectal Cancer: A Cost Analysis from A Single Institute in Korea Se-Jin Baek • Seon-Hahn Kim • Jae-Sung Cho Jae-Won Shin • Jin Kim
•
Published online: 2 August 2012 Ó Socie´te´ Internationale de Chirurgie 2012
Abstract Background Since its introduction, robotic surgery has been applied actively in several fields of minimally invasive surgery, and its use in the field of colorectal surgery is also increasing. In the studies to date, feasibility and safety have been the main focus, but the economics involved are important to examine. We compared the economics of robotic surgery with those of laparoscopic surgery for rectal cancer. Material and methods We analyzed the clinical characteristics, total hospital charges, payments, operating room costs, and hospital profits for patients who underwent robotic and laparoscopic resection of rectal cancer at Korea University Anam Hospital between July 2007 and August 2010. Results From July 2007 and August 2010, 154 robotassisted and 150 laparoscopic rectal surgeries were performed. The patient demographics were similar in the two groups with the exception of tumor location (6.7 vs 8.7 cm distal to the anal verge; p = 0.043), preoperative chemoradiotherapy (22.7 vs 8 %; p = 0.001), and operative time (285.2 vs 219.7 min; p = 0.018). Postoperative course and complications were also similar in the two groups. The
This study was presented at the Annual Convention of the Korean Society of Coloproctology; April 1–3, 2011; Gwangju, Korea. S.-J. Baek S.-H. Kim (&) J.-S. Cho J.-W. Shin J. Kim Colorectal Division, Department of Surgery, Korea University Anam Hospital, Korea University College of Medicine, Inchon-ro 73, Seongbuk-gu, Seoul 136-705, Korea e-mail:
[email protected] S.-J. Baek e-mail:
[email protected]
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total hospital charges in U.S. dollars ($14,647 vs $9,978; p = 0.001) and payments made by patients ($11,540 vs $3,956; p \ 0.001) were significantly higher in the robotic group. Hospital profit was significantly lower in the robotic group than in the laparoscopic group ($689 vs $1,671; p \ 0.001). Conclusions Robot-assisted surgery is more expensive than laparoscopic surgery for rectal cancer. Considering that robotic surgery can be applied more easily for low-lying cancers, the cost-effectiveness of robotic rectal cancer surgery should be assessed based on oncologic outcomes and functional results from future studies.
Introduction Since the laparoscopic resection of colorectal cancer was first reported in 1991, it has become more popular [1]. Its expanding use in comparison with conventional laparotomy has been fueled by widely recognized clinical benefits, including smaller surgical incisions, shorter recovery and hospitalization times, and less pain and intraoperative blood loss. Several randomized clinical trials have been conducted to compare oncologic outcomes between laparoscopic surgery and conventional open surgery in the treatment of colorectal cancer [2–4]. Despite its clinical advantages, many colorectal surgeons are hesitant to begin using laparoscopic surgery. Key reasons for this are the technical obstacles of using laparoscopic instruments and the fear of the steep learning curve. Robot-assisted laparoscopy is a technology that has emerged as one approach to help surgeons address these challenges, and it has been adopted rapidly in many surgical fields. Because its benefits are maximized in narrow spaces such as the pelvis or mediastinum, robot-assisted
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laparoscopy has been employed most prominently in the fields of urogynecologic and cardiac surgery since its invention [5–7]. Recently, rectal cancer is also drawing attention as a good candidate for robotic surgery, and its application in this field has increased. The studies of robotic colorectal surgery to date have focused primarily on feasibility and safety [8–13]. Clinical outcomes suggest that it is equivalent to conventional laparoscopy when considering important endpoints, such as operative time, blood loss, and hospital stay. At the same time, the problem of robotic surgery’s high costs has been one drawback to this technology from the beginning [14– 20]. The systems typically cost $1–$2.3 million (Intuitive Surgical Investor Presentation Q2 2010), not including ancillary equipment such as endoscopic wrist instruments, drapes, and disposable equipment. Therefore, the economic aspects of robotic colorectal surgery will be an important point of dispute in the future [21]. Because of the lack of high-level clinical and economic evidence comparing robotic to conventional laparoscopic surgery, however, a comprehensive understanding of its value for routine colorectal surgery remains uncertain. We compared the costs of robotic colorectal surgery with those of laparoscopic surgery for especially rectal cancer, taking into account such factors as total hospital charges, payments, operating room (OR) costs, and hospital profits.
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Total hospital charges and payments Total hospital charges were divided into several categories, including charges for each case for the operation, anesthesia, laboratory and radiologic studies, nursing care, medical therapy, and total hospital consumables during whole hospitalization. Robotic operation charge was a fixed cost, with prices ranging from $7,150 to $10,700, including all consumables used in the operating room (OR), and it was paid by the patients as a non-benefit service charge. In the robotic group, OR consumables were excluded from the calculation of total hospital consumables. The laparoscopic operation charge for a low anterior resection was $955 prior to July 2009, and subsequently increased to $1,240. The OR consumables were separated from operation charges, and they were counted in the total hospital consumables. The laparoscopic operation charge and some consumables were reimbursed by the Korean National Health Insurance Corporation (NHIC) as a benefit service charge. Hospital charges were divided into benefit service charges and non-benefit service charges. In Korea, 80 % of the benefit service charges are reimbursed by the NHIC, and all non-benefit service charges are paid by the patients. Patients pay 20 % of the benefit services. For patients with cancer, an additional 10 % of charges are reimbursed. The charges for each item were determined by a review of both the medical records and the ultimate hospital bill.
Patients and methods Operating room costs and hospital profits The patients in the present study underwent curative resection of rectal cancer at Korea University, Anam Hospital between July 2007 and August 2010. Patients were eligible for this study if they had primary rectal cancer with biopsy-proven adenocarcinoma localized within 15 cm of the anal verge. We compared the patients’ age, sex, body mass index (BMI), tumor location, operative procedure, operative time, postoperative course, hospital stay, and complications. Access during laparoscopic surgery was gained using five ports, and a medial-to-lateral sequence was used for the pedicular approach. Four 8 mm da Vinci instrument ports, one 11 mm camera port, and one 5 mm assistant port were used in robotic surgery, and we utilized a totally robotic surgery with a single docking method that consisted of phases in both the abdomen and pelvis with da Vinci Systems. The ports were redocked only once without movement of the robotic cart when moving from the abdominal phase to the pelvic phase. Other details of the procedure were described in our previous report [11]. Surgical methods used were similar between the two groups. The study period started on the day of admission for surgery and ended on the day of discharge from the hospital.
Operating room costs were defined as direct costs, which are different from indirect or intangible costs. Our analyses of OR costs were primarily done using the methods of a cost accounting department with activity-based costing (ABC). Because the cost center in this method is based on the location of the event, with laparoscopic operations performed in several ORs sporadically versus the robotic operations always performed in a specialized OR, certain aspects could not be calculated, such as depreciation cost in the laparoscopic group, and the results should be interpreted with this in mind. Operating room costs consisted of labor, supply, and consumables costs. Labor costs were calculated based on the hourly rate of pay according to the salaries of the medical officers involved, including surgeons and anesthesiologists, nursing staff, physician assistants, and other personnel in the OR, by referencing the numbers and types of personnel listed on the OR records. These records were also used in the calculation of OR utilization time. The OR resources used in robotic surgery were calculated as supply costs, paid by the hospital to the supplier and not imposed on patients. Robot consumable costs included robot-specific equipment, such as Cadiere forceps or Maryland bipolar forceps. The OR
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consumable costs included stapling devices, suture materials, and disposable drapes, as well as reusable laparoscopic instruments, including bowel graspers and laparoscopic clips. In the robotic group, robot and OR consumables were not chargeable. The depreciation costs for OR resources in robotic surgery were calculated after estimating the monthly use of these items on a 5-year depreciation schedule. The OR resources used in laparoscopic surgery could not be calculated, so OR consumable costs in laparoscopic surgery are classed as chargeable items and were excluded from the calculation of OR hospital profits, as they were refunded as benefit or non-benefit service charges to the hospital. Operating room hospital profits were calculated by subtracting operation charges from the labor and supply costs of the OR. Operation charges were one of the many categories shown on the hospital bill.
Statistical analysis Nonparametric data are expressed as means and ranges. We used the v2 or Fisher’s exact tests for categorical variables
Table 1 Clinical characteristics and postoperative courses of patients, by procedure
and Student’s t-test for continuous variables to compare the robotic and laparoscopic surgery groups with regard to differences in costs and charges. Differences were considered significant if the estimated p value was less than 0.05. All charges and costs are expressed in U.S. dollars at the December 2010 exchange rate (1,120 won = 1 dollar).
Results From July 2007 through August 2010, 154 robot-assisted and 150 laparoscopic rectal surgeries were performed. The patient demographics were similar in the two groups (Table 1). However, tumor location was more distal (6.7 vs 8.7 cm from the anal verge, p = 0.043) and preoperative concurrent chemoradiotherapy (CCRT) was performed more often in the robotic group (22.7 vs 8 %; p = 0.001). Surgical procedures were also similar in the two groups, with the exception of operative time (285.2 min in the robot-assisted group vs 219.7 min in the laparoscopic group; p = 0.018). Postoperative course and complications were not different in either group.
Robot-assisted (n = 154)
Laparoscopy (n = 150)
Male
105 (68.2 %)
109 (72.7 %)
Female
Gender
0.617 49 (31.8 %)
41 (27.3 %)
Age (years)
59.1 ± 12.2 (30–89)
62.3 ± 10.9 (35–97)
0.820
BMI (kg/m2)
23.4 ± 3.1 (16.9–33.1)
23.1 ± 3.0 (16.3–30.9)
0.745
Distance from AV (cm)
6.7 ± 3.5 (1–15)
8.7 ± 3.8 (1–15)
0.043
Neoadjuvant CCRT
35 (22.7 %)
12 (8 %)
Operative procedures
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0.001 0.627
Anterior resection
3 (1.9 %)
18 (12 %)
Low anterior resection
104 (67.5 %)
112 (74.7 %)
Intersphincteric resection and coloanal anastomosis
36 (23.4 %)
14 (9.3 %)
Abdominoperineal resection
11 (7.1 %)
4 (2.7 %)
Total proctocolectomy and IPAA
0
2 (1.3 %)
Operative time (min)
285.2 ± 69.1 (130–475)
219.7 ± 71.2 (95–465)
0.018
Blood loss (ml)
167.8 ± 26.1 (0–1,500)
126.2 ± 267.7 (0–1,500)
0.200
Time to first flatus (days)
2.1 ± 1.0 (0–8)
2.2 ± 1.0 (0–7)
0.656
Time to defecation (days)
2.5 ± 1.2 (0–7)
2.7 ± 1.3 (0–8)
0.208
Time to oral feeding (days)
3.0 ± 2.2 (1–17)
2.9 ± 2.4 (1–21)
0.781
Postoperative hospital stay (days)
11.1 ± 7.0 (5–50)
10.8 ± 8.6 (4–75)
0.819 0.330
Complications BMI body mass index; AV anal verge; CCRT concurrent chemoradiotherapy; IPAA ileal pouch–anal anastomosis
p Value
50 (32.4 %)
41 (27.3 %)
Anastomotic leakage
17 (11.0 %)
18 (12.0 %)
Anastomotic bleeding Postoperative ileus
4 (2.6 %) 19 (12.3 %)
2 (1.3 %) 7 (4.7 %)
Other
10 (6.5 %)
14 (9.3 %)
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Table 2 Total hospital charges and payments by procedure Robot-assisted (n = 154) Total hospital charges (US$) Operation Anesthesia
Laparoscopy (n = 150)
14,647 ± 3.822 (6,350–35,156) 8,849 ± 1,593 (1,855–13,393) 667 ± 175 (433–1,975)
9,978 ± 3,549 (5,611–29,403) 2,289 ± 587 (1,080–4,301) 581 ± 195 (308–1,597)
p Value 0.001 \0.001 0.174
Laboratory
672 ± 360 (194–2,831)
709 ± 505 (219–3,651)
0.840
Radiology
872 ± 1,048 (98–7,890)
829 ± 738 (9.6–3,395)
0.683
Nursing care
191 ± 143 (45–1,406)
250 ± 438 (34–4,715)
Medical therapy Total hospital consumables Other
13 ± 16 (0–87)
15 ± 18 (0–88)
0.117 0.659
873 ± 9,755 (82–4,105)
3,331 ± 737 (1,605–7,385)
\0.001
2,532 ± 2,100 (733–13,144)
1,875 ± 1,313 (538–9,346)
0.473
Compensated charges (US$)
13,644 ± 3,406 (6,350–32,412)
9,065 ± 3,224 (5,611–28,092)
\0.001
Payments (US$)
11,540 ± 2,263 (2,685–18,406)
3,956 ± 1,170 (1,470–8,572)
\0.001
The total hospital charges and payments of the two groups are outlined in Table 2. The charges for anesthesia, laboratory and radiologic studies, nursing care, and medical therapies were not different in the two groups. The operative charge was significantly higher in the robotic group than in the laparoscopic group ($8,849 vs $2,289; p \ 0.001), whereas the total hospital consumables charge was higher in the laparoscopic group than in the robotic group ($3,331 vs $873; p \ 0.001). The total hospital charges were about 1.5 times higher in the robotic group ($14,647 vs $9,978; p = 0.001). Because some patients received immediate postoperative chemotherapy or radiotherapy that is relatively expensive, we re-calculated the total hospital charge to compensate for these factors. The compensated total hospital charges were about 1.5 times higher in the robotic group than in the laparoscopy group ($13,644 vs $9,065; p \ 0.001). Moreover, actual payments by patients were also significantly higher in the robotic group, and the gap in payments was larger by nearly 3 times ($11,540 vs $3,956; p \ 0.001). For the periodic alterations in the robotic group, we found that the total hospital charge and payment were higher in the early period because this novel system was still unstable, but they became lower and stabilized as time went on (Fig. 1). At the same time, the total hospital charge and payment in the laparoscopic group increased with time, and this was reflected in the increased operative charge after July 2009. Operative charge represented a relatively large part of the total hospital charge in the robotic group, whereas the total hospital consumables charge comprised a larger proportion of costs in the laparoscopic group (Fig. 2). Because some patients’ costs could not be calculated, the number of patients included in the analysis was 152 in the robot group and 144 in the laparoscopic group. Operation and anesthetic charges, which are categorized as OR incomes from the perspective of hospital profit, were
Fig. 1 Progressions of total hospital charges and payments in robotassisted and laparoscopy groups according to accumulation of cases
significantly higher in the robotic group than in the laparoscopic group ($8,740 vs $2,064; p \ 0.001 and $543 vs $441; p \ 0.001), and total OR incomes were also higher ($9,306 vs $2,529; p \ 0.001). As OR costs, labor, and indirect costs were also significantly higher in the robotic group ($1,109 vs $850; p \ 0.001 and $11 vs $8; p \ 0.001). Robot consumables, unchargeable OR consumables, and depreciation costs, which were omitted in the laparoscopic group, were very large parts of the OR cost in the robotic group. Total OR costs were ten times higher in the robotic group than in the laparoscopic group. Therefore, hospital profit was significantly lower in the robotic group ($689 vs $1,671; p \ 0.001). The robotassisted group had a structure of higher OR income but
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Fig. 2 Compositions of total hospital charges in the robotassisted and laparoscopy groups (Color figure online)
higher OR cost; it did not show a profit in the early period, but now has started generating some income as time has progressed (Fig. 3). Although OR income was lower in the laparoscopic group, OR cost was also low, and so the hospital profit was relatively high. The profit was higher in the later period than in the early period, likely because the operative charge increased.
Discussion In agreement with several previous studies in other fields, we found that hospital charges and OR costs were significantly higher for the robotic group than for the laparoscopic group [15–20]. Total hospital charges in the robot-assisted group were higher because of the higher operative charge, which was not compensated for by the higher total hospital consumables charge in the laparoscopic group. Because robotic surgery did not lead to decreased length of hospital stay or higher hospital turnover rate, unlike that seen when comparing laparoscopic surgery with open surgery, it is very difficult to see the advantages of robot-assisted surgery over laparoscopic, even in countries that have higher
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hospitalization charges than in Korea. A larger total hospital charge increases the private burden and total health care cost, and it will likely disrupt the ideal distribution of resources from a public welfare perspective [14, 21]. The OR costs were greater in the robotic group as a result of higher initial investments, maintenance costs, and longer operative times. Previous studies also have demonstrated significantly longer operative times for robotic surgery as compared to laparoscopic surgery [8–13]. One of the reasons for this discrepancy is the need for additional time in robotic surgery for docking, but trends show that docking time decreased as the surgical teams gained experienced. Moreover, the demographics were different between the two groups. The location of the tumor was more distal in the robotic group and more patients who underwent preoperative CCRT were included than in the laparoscopic group. This disparity reflects surgeons’ preference for the robotic method in treating tumors that are more difficult to operate on. It can be assumed that this difference in tumor characteristics led to an increase in operative time, and therefore higher associated costs, such as anesthesia charge, labor, and indirect costs, in the robotassisted group. Actually, we performed a subgroup analysis
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2727 Table 3 Operating room costs and hospital profits Robot-assisted (n = 152)
Laparoscopy (n = 144)
p Value
OR incomes (US$)
9,306 ± 1,473 (5,825–11,509)
2,529 ± 459 (1,648–4,238)
\0.001
Operation
8,740 ± 1,473 (5,357–10,714)
2,064 ± 420 (1,237–3,704)
\0.001
Anesthesia
543 ± 139 (349–1,635)
441 ± 102 (246–747)
\0.001
Nursing care
23 ± 12 (2.7–130)
23 ± 11 (5.4–101)
0.961
8,617 ± 1,588 (5,600–13,471)
857 ± 281 (352–1,888)
\0.001
Labor costs
1,109 ± 279 (496–1,872)
850 ± 279 (349–1,871)
\0.001
Robot consumablesa
3,710 ± 625 (2,274–4,547)
–
–
OR consumablesa
1,542 ± 531 (594–3,304)
–
–
Depreciation costs
2,246 ± 974 (841–7,148)
b
–
OR costs (US$)
Indirect costs Hospital profit (US$)
11 ± 2.7 (5.4–20)
8 ± 2.7 (2.7–18) \0.001
689 ± 1,348 (–3,996 to 3,015)
1,671 ± 461 (421–3,758)
\0.001
OR operating room
Fig. 3 Operating room costs (OR) and hospital-profit in the robotassisted (a) and laparoscopy (b) groups
for intersphincteric resection with coloanal anastomosis, although the results are not described separately in this article, to calibrate the effect from differences in patient demographics. Operative time in the robotic group was still longer than in the laparoscopic group (321.1 min vs 284.6 min; p = 0.043), and the economic results were also same as in the present study (all, p \ 0.001). However, overall, the difference associated with operative time did not seem to have much of an effect compared with the other costs. The largest components of the OR costs in the robot group were the initial investment cost, which was expressed as depreciation cost, and the maintenance cost. Because we could not assign a depreciation cost to the laparoscopic group, the actual difference in OR costs between both groups might be smaller. However, the depreciation cost in the robotic group likely still outpaces that of the laparoscopic group because of the enormous initial investment cost. In addition, the robotic group included all robot-related consumables within the fixed cost, and these consumables are expensive, accounting for 60.9 % of total OR costs in the robot group, and
a
Not chargeable to patients
b
Could not be calculated
were not reimbursed, as in the laparoscopic group (Table 3). Thus, total hospital profit in the robotic group was lower than in the laparoscopic group. Furthermore, it is unlikely that the initial and maintenance costs of the robot will significantly decrease in the future as the manufacturing company currently has a monopoly. This is not a ‘‘cost-effectiveness’’ study but a ‘‘costanalysis’’ study. The real value of robotic versus laparoscopic rectal surgery should be evaluated with many different factors, including clinical quality, education/training efficacy, and surgeon benefits. All these issues should be further studied in solid scientific methods. It is important to keep in mind that the measurement of effectiveness used in the current study was only for postoperative short-term outcomes such as postoperative recovery, complications, and length of hospital stay. We anticipate that robotic surgery has additional potential advantages as we have previously identified. Because it is more ergonomic, robotic technology facilitates minimally invasive surgery among patients, for example, with very low rectal cancer which is difficult to access by conventional laparoscopy. This access may be a priceless advantage of this technology from the perspective of patients and surgeons. Potential benefits of oncologic outcomes and results of sexual/ voiding functions need to be further investigated. At
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present, there is a multicenter, randomized, controlled trial to assess total mesorectal excision (TME) completeness and local recurrence in progress in Korea, including our own institution. The ability to see in three dimensions and the stable working platform of robotic surgery are thought to be advantageous in terms of nerve preservation, and therefore should lead to positive outcomes in sexual/voiding function in rectal cancer patients. This has yet to be formally studied. It may be a flawed conclusion that costeffectiveness is lacking because data is only now becoming available. Therefore, judgment on cost-effectiveness should be postponed until additional data is obtained. Another matter that must be considered is whether or not to discard the robotic systems already installed as the medical infrastructure. Hospitals have purchased robotic systems based on the demand for urology or gynecology rather than for colorectal surgery and the installation is still in progress rapidly. Between 2007 and 2009, the number of da Vinci systems, the leading robotic technology, that were installed in U.S. hospitals grew by approximately 75 %, from almost 800 to around 1,400, and the number that were installed in other countries doubled, from 200 to nearly 400, according to Intuitive Surgical, the da Vinci manufacturer. According to the investor presentation Q2 2010 by Intuitive Surgical Corporation, 1,571 da Vinci systems, including 1,160 in the United States, 276 in Europe, and 135 in the rest of world, had been installed as of the first half of 2010, and this number is expected to increase continuously. Some 30 da Vinci systems are installed in Korea alone. The excessive installation of robotic systems may arise from a combination of patient demand, competition between hospitals, and surgeons’ desire for new technical challenges. Whatever the causes, the expansion of robotic surgery indicates that it will continue for the foreseeable future. Making the best use of existing infrastructures will be paramount to the cost-effective use of this technology. The issue remains whether patients and hospitals should cover all the expenses for new technology. Given the problem of increasing total health care costs, the idea that the government should share some of the burden needs be considered carefully, especially in view of the gap in payments between the robotic and laparoscopic surgery groups. In terms of hospital management, it is necessary to devise solutions for the issue of lower hospital profit associated with robotic surgery. It will be difficult to save money because some costs are fixed. Only the depreciation costs can decline, and this can be achieved by increasing the number of operations performed. Thus, theoretically, it is possible to gain in profits. Further investigation into ways to offset the costs of this technology is required. An important limitation of the present study is that we were unable to calculate the depreciation costs in the
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laparoscopic group. Also, the two groups were heterogeneous in terms of some variables such as the level of tumor and the incidence of preoperative CCRT. Despite such limitations, this may be a very important study at this point in time. As far as we know, this is the first cost-analysis study comparing robot-assisted surgery and laparoscopy for rectal cancer surgery. This study was possible because laparoscopic and robotic surgery is actively performed in the scope of general surgery, especially colorectal surgery, more often in Korea than any other country. Because costanalysis usually depends on the medical service system of each nation, these results are not generalizable to other countries. However, this study may be helpful in analyzing the trend generally. It would be rash to conclude that robot-assisted surgery is not cost-effective in rectal cancer surgery based solely on the results to date. Further results that demonstrate definite superiority of robot surgery in oncologic or functional respects that may compensate for its high costs are needed for further analysis. Robotic surgery may fall by the wayside because of market forces, if future studies do not yield results that show it is superior to laparoscopic surgery. In summary, robot-assisted surgeries were performed more often in patients with tumors located more distal in the rectum or who had received preoperative chemoradiation. The postoperative course and complications were similar in the robotic and laparoscopic groups. The total hospital charges and payments by patients were significantly higher in the robotic group. Hospital profit was significantly lower in the robotic group. The ultimate costeffectiveness of robotic rectal cancer surgery should be assessed according to oncologic and functional results from studies now in progress.
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