BB&T Contributing Editor
The American College of Surgeons (Chicago) has more than 74,000 members, with more than 4,000 members from countries outside the U.S. and Canada, making it the largest organization of surgeons in the world.
This widely diverse group met in San Francisco in October with equally diverse interests, as general surgery is for all practical purposes, becoming a collection of sub-specialties; with workshops, lectures, and courses that supported each specialty topic. Although virtually impossible to cover all subspecialties, those surrounded by excitement included hepatobiliary, bariatric and metabolic, and NOTES surgery.
A surgical subspecialty experiencing an emergence of new therapies is hepatobiliary surgery, with the incidence of liver cancer growing exponentially in the U.S. and becoming the most prevalent cancer worldwide, with 500,000 new cases diagnosed annually.
Thought leaders believe that this rise in liver cancer is due to a dramatic rise in incidence of its precursor, hepatitis C, which predisposes certain people to contract the cancer, and is predicted to double in the U.S. over the next five years.
According to the National Cancer Institute (Bethesda, Maryland), more than 21,000 new cases of liver cancer will be diagnosed in 2008 in the US, with 18,000 patients dying of liver cancer in the same year.
Conventional thinking has been that resection of a hepatoma, or tumor in the liver, is too risky due to the vascularity of the liver. Advancements in technology from four companies have contributed to the development of devices that can cut and coagulate the liver without excess blood loss. These include the Habib device, acquired through the January 2007 acquisition of RITA Medical Systems (Fremont, California) by AngioDynamics (Queensbury, New York), which delivers bipolar RF energy through a four-needle device, significantly reducing blood loss and allowing the surgeon to perform a non-segmental (just the hepatoma) resection.
AngioDynamics also introduced a novel new device system called Nanoknife that incorporates irreversible electroporation (IRE), a non-thermal tissue ablation technique in which electrical fields are used to create nano-scale defects in cell membranes, leading to the demise of the cell.
IRE is a physiologic — rather than thermal — change at the cellular level that may have advantages of more precise excision without any damage at all to healthy structures around it. Research is being conducted at select sites in the U.S. using irreversible electroporation for treatment of tumors.
Microsulis' (Denmead, UK) Oncology and Interventional Division has developed a non-thermal method of liver resection with their microwave system for targeted soft tissue ablation that is also being studied in certain centers.
Covidien (Boulder, Colorado) received 510(k) clearance from the FDA last month for microwave ablation use in soft tissue, and is now the first microwave ablation system available globally. Its Evident microwave ablation system is intended for coagulation of soft tissue during percutaneous, laparoscopic and open surgical procedures.
No surgical conference would be complete these days without an update on NOTES surgery. In a post-graduate course on "Minimally Invasive Surgery: The Next Step," Jeffrey Hazey, MD, of the department of surgery at Ohio State University Medical Center (Columbus), presented "Natural Orifice Translumenal Endoscopic Surgery in the Foregut: Translumenal Drainage Techniques, New Diagnostic and Therapeutic Techniques."
He reminded the audience that NOTES is not an entirely new surgical technique; that in fact, percutaneous endoscopic gastrostomy (PEG) and endoscopic cyst-enterostomy procedures have been around for years. "What is new about NOTES is the organ of access," Hazey said, is that "never before have we considered the stomach or vagina as a port of entrance into the abdomen."
He rhetorically asked, "Why are we looking at NOTES?" Because, he said, "it is believed that NOTES may provide a quicker recovery, less immune suppression, better cosmesis, no skin wound infections, the ability for some procedures to be moved into an office setting under local anesthesia, and better viewing of the abdomen. The only major risk is intra-abdominal infections."
If for no other reason but diagnostic, NOTES can be useful for staging cancer, adhesions, procedures for the morbidly obese and evaluation of the abdomen, including trauma. "The views of the abdominal wall are superior to those of laparoscopy," Hazey found in a double blind study where surgeons were asked to evaluate the pancreas and abdominal wall.
The surgeons were divided into two equal groups, one viewing from an endoscope and the other viewing through a laparoscope — each group was unaware of the type of scope they were using.
He told the audience that any NOTES procedure was required to be performed under an IRB, and that in his current ongoing study he was performing gastrotomies only on patients that had to have one anyway.
Hazey said that so far in his research, "open gastrotomy resulted in no clinically significant peritoneal contamination and that it appeared that pre-operative gastric lavage with antibiotics may not be necessary."
According to this summary presentation, it looks as though there may be quite an upside to NOTES procedures in the future.
In the same postgraduate course, Scott Shikora, MD, professor of surgery at Tufts University School of Medicine (Boston), discussed "Emerging Technologies and the Future of Bariatric Surgery."
"There is a large unmet need among the obese for the development of new and novel procedures that might be more appealing than surgery to patients," he said. "Some of these procedures offer new mechanisms of action that do not rely on the traditional caloric restriction or malabsorption that are the mainstay of the current surgical procedures. Others take advantage of the current interest in NOTES and are performed endoscopically instead of trans-abdominally" (see Table 5).
There continues to be much debate regarding mechanism of action for the multitude of interventional procedures, some suggestions being: nutrient malabsorption, alteration of gut hormones, dumping of lipids into hindgut, changes in GI nerve function, or reaction to chronic foreign body.
"The dramatic increase in demand has stimulated tremendous interest in developing new technologies and operative procedures," Shikora said. "Although bariatric surgery is entering a new era rich with rapid change and exiting innovations, keep in mind that currently none of these new modalities have been adequately studied to warrant introduction into practice. Some may ultimately be deemed worthy for use while others will likely fail to achieve meaningful results and be abandoned."
New techniques becoming robotic alternatives?
National and international laparoscopic surgeons convened at the Society of Laparoendoscopic Surgeons (SLS; Miami) 17th annual meeting in Chicago in September to share what they have researched in minimally invasive techniques spread across multi-specialties, such as urology, gynecology and general surgery.
With an international membership of more than 6,000 surgeons, the SLS offers the unique approach of bringing together all the subspecialties that use the techniques and tools of minimally invasive surgery. Just when one thought minimally invasive surgery couldn't get any less intrusive, new technologies are discovered that are one step less invasive than the most recent advance.
Such was the case at this meeting, where single-port surgery, articulated laparoscopic instruments, and other novel devices were launched that allow the surgeon and patient the benefits acquired with less traumatic techniques.
One way to convert more open surgeries into laparoscopic surgery is to allow more movement inside the abdomen, which in some surgeries cannot be done with rigid laparoscopic instruments. By adding articulation to the rigid laparoscopic instrument, the surgeon can enjoy better movement and manipulation of organs within the abdomen and perform tasks that cannot be done with rigid instruments.
Several companies have developed such instrumentation, which has enabled surgeons to do more procedures laparoscopically. In a presentation, "Comparison of Conventional and Second-Generation Articulating Laparoscopic Instruments," Chandru Sundaram, MD, of Indiana University Medical School, (Indianapolis), reported on the differences in conventional vs. articulating laparoscopic instruments when used to perform a series of standardized tasks performed by novices.
She found that except for one cutting task where the articulated instrument group was slower but more accurate, "there were no other statistically significant differences in speed, accuracy, or comfort between the two groups." Sundaram added, "The limitations of conventional laparoscopy have driven the development of articulating instruments. These instruments may help expand the indications for conventional laparoscopy especially in areas where robotic technology is not available or affordable."
Five companies are addressing this opportunity, each with its own strategy.
Intuitive Surgical (Sunnyvale, California) has licensed from Ethicon Endo-Surgery (Cincinnati) a line of Harmonic instruments that use ultrasound to simultaneously cut and coagulate, for use with its da Vinci robotic system. The robot employs a fully articulating arm called Endowrist, to which the harmonic instruments attach.
At this point, Ethicon Endosurgery is not selling a separate, independent line of articulating laparoscopic instruments.
Novare Surgical (Cupertino, California) and Starion Instruments ( Sunnyvale, California) partnered in a distribution agreement that allows Starion's tissue welding technology to be integrated into Novare's articulated instruments, resulting in both a full freedom of movement hand-held laparoscopic instrument and cut-and-seal capability. Novare distributes instruments manufactured by Starion, incorporating the latter's tissue-welding technology.
CambridgeEndo (Framingham, Massachusetts) manufactures a line of hand-held fully articulating laparoscopic instruments that employ RF energy for coagulation, as does Covidien (Norwalk, Connecticut).
It is curious that none of these companies claim or even suggest that their instruments could be considered an alternative to the surgical robot, but is some ways, they truly are.
The articulated instruments are designed to allow for more surgeries to be performed laparoscopically, to improve the surgeon's dexterity, to allow for better suturing, and all of the associated benefits for the patient: shorter hospital stay, less chance of blood loss, less chance of infection, quicker return to activities – much the same as is true for the robot.
Granted, the robot has additional advantages such as 3-D visualization, more finesse when suturing, and tremor removal, but one might beg the question of cost vs. benefit.
One thing the robot has not yet performed, but articulated handheld laparoscopic instruments have, is Single Port Access, coined SPA, surgery where three or four trocars are placed within a single opening in the abdomen, usually the umbilicus; instead of three to four small stab incisions placed in different spots on the abdomen.
Results of the first 100 cases were reported here by Paul Curcillo, MD, of Drexel University (Philadelphia), wherein he entered (primarily) the umbilicus with a 1.5 cm to 2 cm incision and placed three trocars within that incision to perform a variety of surgical procedures.
Curcillo found that "operative times, results and outcomes were similar for comparable standard multiport procedures." He cautioned the audience that "long-term follow-up is necessary to ensure that no added complications occur later compared with standard multiple-port techniques."
He also said that initially he always used articulating instruments for SPA surgeries but found that for most procedures there is enough "independence of movement" with standard instruments. He now has an articulated instrument ready for each case, but doesn't open it unless is it needed, keeping the costs down for performing these new procedures.
Curcillos said, "All the SPA procedures are the same standard procedures, done in the same way. The only difference is the access. We don't change the game.
Currently, there are 25 surgeons trained to perform SPA surgery, with more signed up to learn from around the world.
Stephanie King, MD, also of Drexel, presented "Single Port Access Hysterectomy and Oophorectomy," which also demonstrated the feasibility of performing surgery through the umbilicus, leaving virtually no scar; unlike laparoscopic surgery where there are three or four stab scars from the various ports used for trocars and cameras.
She compared two patient groups: one that had SPA surgery and the other that underwent standard laparoscopic surgery, reporting: "Patient populations and surgical indications were similar in both groups. Operative times were comparable, as was blood loss and length of stay."
King concluded that "Early results comparing SPA procedures to standard multiport procedures demonstrate comparable results, but allow us to perform the procedures through a single incision concealed within the umbilicus."
Both Curcillos and King stressed the importance of maintaining the same standard dissection technique and doing the same procedure as always, just reducing the number of abdominal entry points to one. Both surgeons said they feel that "SPA surgery is a viable, cost-conscious alternative to multiport surgery."
SPA surgery allows the surgeon to perform the same procedure, with the same outcome, and at the same cost, but gives the patient only one hidden scar in the bellybutton.
Another advance in general laparoscopic surgery that was launched here and also received an innovation award was the Prosurgics (Cupertino, California) Free Hand robotic camera holder.
The camera is securely clamped onto the OR table, while the surgeon wears a controller attached to his surgical cap. The Free Hand device then moves the camera according to the surgeon's head movements, leaving the surgeon free to move the camera where he wants it without an assistant doing it for him.
The Free Hand laparoscopic camera holder was designed to bring affordable and cost-effective robotic support to the OR; acting as an extension of the operating surgeon and potentially eliminating the requirement of an assistant.