Role of minimally invasive surgery in gynecologic malignancies

Positioning of the patient

Positioning of the patient is critical in advanced MIS. For most gynecologic procedures, the appropriate position is in a dorsal lithotomy position with adjustable Allen stirrups to allow for manipulation of the uterus and laparoscopic assisted vaginal hysterectomy (LAVH) or total laparoscopic/robotic hysterectomy (TLH) as indicated. In patients who do not have a uterus or in whom the uterus is not anticipated to be removed, placement in a supine position may be appropriate. The patient’s arms should be tucked by her side to allow mobility and ergonomic comfort for the operating surgeon and assistant. Care should be used in protecting both the upper and lower extremities with appropriate padding to prevent pressure points and nerve injuries, and several positioning systems that rely on friction or barrier blocks and straps are available. For laparoscopic surgery, video monitors should be placed on each side of the table across from the operating surgeon and the assistant and located toward the foot of the table. This allows for comfortable positioning of the surgeon in a natural angle of viewing the video monitor and minimizing counterintuitive surgical movement. Placement of the monitors toward the patient’s head can be considered when extensive upper abdominal surgery is undertaken ( Fig. 20.1 ).

Port sites and setup

The number, position, and size of trocars for laparoscopic surgery depend on the surgery anticipated. In cases that require removal of an adnexal mass or lymph nodes, a 10- to 12-mm accessory port will be needed for extraction of the specimen. Most LS can be accomplished successfully with the placement of a 5- or 10-mm port at the level of the umbilicus for camera placement, with or without a 10- to 12-mm port suprapubically, and a 5-mm port in each of the lateral lower quadrants. Gynecologic oncologists usually use a total of three to six ports to obtain adequate exposure and accomplish advanced pelvic procedures. Safe placement of the primary port, or camera port, is the most critical part of the procedure in terms of minimizing major surgical complications. A number of surgical approaches have been described and accepted for placement of the primary port. An oropharyngeal tube should be used to achieve gastric decompression before placement of the Veress needle or primary trocar. Lateral ports can safely be placed in a line one-third of the distance from the anterior superior iliac spine to the umbilicus. The oncologist should take care when placing the lateral port and do so under direct visualization with inspection of the deep inferior epigastric vessels lying along the lateral boundary of the rectus abdominis muscles. These can be directly identified lateral to the obliterated umbilical ligaments ( Fig. 20.2 ). Transillumination will not reliably reveal the location of these vessels.

The port-site setup for robotic surgery is different from that for laparoscopic procedures because ports are generally placed above the umbilicus for the SI system and through the umbilicus for the Xi system ( Fig. 20.3 ). With the Xi system’s rotating boom and potential for multi-quadrant surgery, variations in port setup may require moving the camera port while keeping all other robotic ports in the same position during surgery. Various port setups have been described for robotic gynecologic oncology surgery. Most gynecologic oncologists use two or four laparoscopic/robotic ports and one or two additional LS ports to be controlled by the bedside assistant. In addition, the robot must be “docked” or attached to the ports, which is usually accomplished between the legs or from the side of the patient. When the surgical procedure commences, the experienced robotic surgeon can efficiently alternate (swap) control of the various robotic ports through a unique clutching system, using both hand and foot controls can operate all instruments in real time and has direct control of both monopolar and bipolar electrosurgical energy sources. Although there is less reliance on the bedside assistant, that person is still instrumental in facilitating the case through robotic instrument changes, manipulation of vaginal instruments, suction irrigation, and the use of an additional grasping instrument for retraction.

In addition to multiport surgery, the options have expanded to single-port surgery or laparoendoscopic single-site surgery (LESS) and robotic single-site surgery. Single-port (Sp) surgery uses a GelPort or Single Incision Laparoscopic Surgery (SILS) port in a 2- to 3-cm (umbilical) incision. Through this port, the camera port and usually two or three additional trocars are placed. Possible advantages include better cosmesis and decreased postoperative pain. Disadvantages such as port crowding, crossing of instruments, and need for advanced laparoscopic skills have limited the uptake for advanced and complicated pelvic surgeries. Robotic single-site surgery allowed for computerized optical reversal of crossing instruments and hands with improved ergonomics and 3D visualization. An articulated needle driver has been added to the Sp platform, further improving surgeon comfort and easier applicability or single-site surgery. Cases must be carefully selected because Sp will not allow for use in very obese patients with thick subcutaneous tissues, and the use of adequate uterine manipulators is imperative without the availability of ports to provide retraction and manipulation. Sp surgery has been FDA approved for urologic surgery and transoral otolaryngology procedures but is still considered experimental for gynecologic surgery.

Surgical procedure and technique

After the ports are placed, actual surgical technique varies little except for the surgical steps required to complete various aspects of the procedure. After successful insufflation and placement of the trocars are accomplished, visual inspection of the abdominal cavity is undertaken, and the patient is placed in a steep Trendelenburg position. As in any surgical procedure, excellent exposure should be accomplished initially and maintained throughout the case. Use of steep Trendelenburg position is necessary, in lieu of packing the bowel, to achieve adequate visualization of the pelvis and lower abdominal region. Lysis of any adhesions holding the small bowel or omentum into the pelvis or lower abdomen should occur before beginning the pelvic and upper abdominal dissection. Laparoscopically folding of the bowel into the upper abdomen will improve visualization in the pelvis. The small bowel is carefully placed in the upper abdomen by flipping the bowel up from a caudad to a cranial position, exposing the mesentery of the small bowel and the aortic bifurcation ( Fig. 20.4 ). Blunt instruments and gentle techniques must be used in this maneuver. In obese patients, body habitus may not allow a steep Trendelenburg position because of unacceptably high peak inspiratory pressure. Surgery may be completed by decreasing the amount of Trendelenburg positioning (while the robot is undocked) or by decreasing the insufflation pressure. Adjusting the respiratory frequency and tidal volume may further improve ventilation. In addition, obesity may prevent adequate mobilization of the small bowel out of the pelvis and upper abdomen to allow for retroperitoneal dissection. Use of a 30-degree camera scope may allow for improved visualization in the pelvis in obese patients depending on the port setup and location of the bowel. Some authors have advocated using additional port sites to help circumvent this problem; laparoscopic paddle or fan retractors may also improve exposure. For both obese and underweight patients, using longer laparoscopic and robotic ports may allow for improved manipulation of instruments during the surgery.

In underweight patients, spacing can be maximized once the patient’s abdomen is fully insufflated with carbon dioxide. The use of a left upper quadrant entry at Palmer’s point can allow maximal spacing of the ports along a smaller abdominal wall surface area. The use of longer ports in underweight patients can move the instruments away from each other and minimize potential instrument crossing during the procedure. The camera port, often placed in the midline for oncologic procedures, may need to be shifted away from the midline in underweight patients to ensure adequate spacing of ports. If using a robotic platform, the authors recommend at least 8 cm of spacing between robotic ports for the Si system. This is in contrast to the Xi system, which requires a minimum of 6 cm of spacing between ports to ensure full functionality. For port positioning, in underweight patients, the ports will often need to offset to maximize the distance between ports compared to obese patients where often ports are placed in a straight line.

The key to successful advanced MIS is the same as that for open laparotomy: access to the retroperitoneum. In the pelvis, this is accomplished by dividing the round ligament laterally or opening the pelvic peritoneum lateral and parallel to the infundibulopelvic ligament. Some surgeons prefer to keep the round ligament intact so they can retract against it to keep the paravesical space open while dissecting tissue. Dissection is then carried down to the level of the external iliac artery, which is then followed in a cephalad and medial direction to the common iliac artery. At this point, the ureter can be found crossing the pelvic brim, and a window can be created between the ovarian vessels and the ureter ( Fig. 20.5 ). Development of the pararectal space is under direct visualization after identification of the bifurcation of the common iliac vessel and the ureter. The surgeon places traction on the ureter, medially developing the pararectal space between the hypogastric artery laterally and the ureter and rectum medially. Care must be taken during this dissection to avoid disrupting the cardinal web deep in the retroperitoneum. Because of the positive pressure environment of MIS resulting from the pneumoperitoneum, the boundaries of the paravesical space can be identified visually during laparoscopic surgery. The superior vesicle artery and umbilical artery are clearly visible as the medial umbilical ligament (see Fig. 20.2 ). Dissection is carried along the external iliac artery to the level of the superior vesicle artery (obliterated umbilical ligament). At this point, the superior vesicle artery is retracted in a medial direction, and the paravesical space is easily developed with the bladder and superior vesicle artery medially and external artery and obturator node bundle laterally. After this is accomplished, the uterine artery can be clearly identified at the origin of the superior vesicle artery from the hypogastric artery. This retroperitoneal pelvic dissection is the cornerstone of any laparoscopic surgery performed in the pelvis, including removal of an adnexal mass, TLH, LAVH, laparoscopic radical hysterectomy (LRH), and PLN dissection ( Fig. 20.6 ). Dissection can be facilitated with a variety of energy sources and clip appliers, each with its own advocates.

Extension of the incision along the peritoneum overlying the right common iliac artery and then along the aorta to the level of the duodenum allows for exposure of the paraaortic retroperitoneum ( Fig. 20.7 ). During this dissection, the peritoneum attached to the base of the cecum can be elevated in an anterior-cephalad direction, providing excellent exposure to the right paraaortic lymph node region. Margins of resection are identical to an open approach and can be extended to the level of the renal vessels. The left-sided paraaortic lymph node dissection requires dissection underneath the inferior mesenteric artery, mobilizing the descending colon and rectosigmoid off the left common iliac artery and retracting the inferior mesenteric artery and ureter laterally and cephalad. This gives excellent exposure to the left paraaortic lymph nodes inferior to the inferior mesenteric artery. Dissection can be continued above the inferior mesenteric artery in a similar manner. Some authors have advocated sacrificing the inferior mesenteric artery to get enhanced exposure to the upper left paraaortic nodes. Others prefer a extra peritoneal approach with ports placed in the retroperitoneum of the left flank and without entering the peritoneal cavity. Insufflation of the retroperitoneum has the advantage of lifting the bowel and avoiding interference of large and small bowel loops in the field of dissection. Lymph nodes are dissected off the IVC and para aortically in a similar way as via the transperitoneal techniques.

MIS in gynecologic oncology is now common, but especially in the underweight and morbidly obese, attention must be made to patient positioning, port placement, and surgical exposure to ensure patient safety. The surgeon needs to obtain experience over time to optimize patient outcomes and emphasize excellent surgical technique. Knowledge of anatomy, the disease process, and surgical technique is key during complicated surgical procedures. To minimize complications that are possible with any major surgical procedure, vigilance and meticulous surgical technique are required.

Cervical cancer

The pioneering reports describing the use of advanced laparoscopic techniques in gynecologic oncology were initially described in patients with cervical cancer in which LS was used for PLN dissection in patients with early-stage disease to assess the feasibility for abdominal radical hysterectomy. One of the initial concerns about MIS in cervical cancer was that the laparoscopic approach would not be as thorough as laparotomy in assessing metastatic cancer and performing a comprehensive lymphadenectomy. Early studies in patients undergoing initial laparoscopic lymphadenectomy before laparotomy confirmed that a thorough pelvic and paraaortic lymphadenectomy is possible via LS, with no positive nodes discovered at laparotomy performed after laparoscopic lymphadenectomy. Once the feasibility of laparoscopic lymphadenectomy was established, the use of MIS for radical surgery in patients with early-stage cervical cancer and for pre-radiation surgical assessment in patients with advanced disease was explored.