Minimally invasive surgery is simply the use of small incisions with specialized equipment to accomplish surgical objectives that would otherwise be completed through larger incisions with conventional equipment. A priority of gyne-cologic oncologists who advocate minimally invasive techniques is to ensure that the adequacy of any oncologic procedure is not compromised in order to complete it laparoscopically.
Not every patient is a candidate for minimally invasive surgery. For example, obesity and previous intraabdominal surgery may, in some cases, obviate an attempt at laparoscopy or necessitate conversion to an open procedure. This is no more clinically significant than extension of incision length during a procedure that begins with a small midline or low transverse incision.
Selection of the surgical incision for gynecologic oncology procedures has always been individualized and not standardized. All patients with early-stage ovary cancer do not undergo exploration through midline incisions of the same length. Patients with early-stage cervical cancer undergo radical hysterectomy via low transverse as well as midline incisions, and the same is true for patients with endometrial cancer.
In fact, surgical-pathologic studies conducted by the Gynecologic Oncology Group (GOG) in patients with ovarian cancer (GOG #41), endometrial cancer (GOG #33), and cervical cancer (GOG #49) did not require incisions of any particular length or direction. In all three studies, adequacy was determined by the operating surgeon unless a part of the required dissection was not undertaken, eg, pelvic lymph node dissection was not performed.[1-4] Lymph node counts were not undertaken, and if any tissue, even if it did not contain lymphatic tissue, was recovered from a specified retroperitoneal site, the dissection was considered to be adequate for protocol purposes.
For patients with cervical cancer undergoing radical hysterectomy (GOG #49), the extent of the dissection was not measured. In fact, there is no accepted measurement of adequacy that pertains to radical hysterectomy. It might even be argued that surgical adequacy in patients with cervical cancer is the individualized resection of parametrial and vaginal tissues.
Minimally invasive surgery is nothing more than another approach now available to surgeons in the late 20th century. Since there seems to be such an emphasis on incision size, it would seem to be incumbent on the author to mention, as a means of comparison, any data that might guide other surgeons in their search for the correct incision size. To his credit, Chi does note, throughout his review, that the adequacy of these techniques has been demonstrated in “highly skilled hands.” We would suggest that, as the 21st century approaches, this situation is no different than the turn of the last century when radical abdominal hysterectomy was being performed by a limited number of highly skilled surgeons.
Laparoscopic Management of the Adnexal Mass
Throughout this review, Chi assumes that staging performed via laparotomy (without specifying the incision) will remain the standard of care and that laparoscopy will be reserved for clinical trials. In referencing Curtin, Chi states that “in the event that an ovarian cancer is encountered, immediate conversion to laparotomy and surgical staging is indicated.” Unfortunately, the Curtin reference offers no data to support this statement. In fact, Curtin writes, “Evidence of probable malignancy is generally accepted as an indication for converting the procedure (laparoscopy) to a laparotomy.” The basis for either statement, when discussing patients with early-stage ovarian cancer, is not readily apparent.
Chi also cites a study by Querleu, in which complete surgical staging, including lymph node dissection to the level of the renal vessels (exceeding GOG requirements), was accomplished laparoscopically. However, Chi then states that “it remains unclear whether apparent early-stage ovarian cancer can be adequately staged laparoscopically.” Clearly, adequate staging can be accomplished laparoscopically by some surgeons in a selected group of patients. Laparoscopy is no more than one of many operative strategies available to surgeons.
Chi is concerned about the possibility that metastatic disease could be missed that might otherwise be detected at laparotomy, and about the risk of rupturing an early-stage cancer. However, he seems surprisingly unconcerned about the incision used for the laparotomy, and leads the reader to believe that all incisions, except trocar incisions, provide the same access to the abdominal cavity. This assumption is simply incorrect. Access to the upper abdomen through a low transverse incision is most often limited, except in either the thin or short-waisted patient. Performance of resection of the pararenal lymph nodes similar to that described by Querleu would require, in most instances, a midline incision extended well above the umbilicus.
If one were to carry Chi’s concerns to the extreme, then all results of surgical studies in gynecologic oncology should be stratified by length and direction of incision in order to ensure purported surgical adequacy. GOG #9302 will help define the feasibility of performing complete surgical staging only in patients with incompletely staged ovarian cancer, as well as the adverse effects associated with this procedure.
Regarding the issue of intraoperative rupture, it is unlikely that a prospective, randomized trial will be designed to test the hypothesis that intraoperative spill of an otherwise stage I ovarian cancer adversely affects survival. Therefore, patients considering surgery, regardless of the incision used, should be apprised of these issues, and the surgeon should take care to avoid unnecessary spill and dispersement of the contents of the mass.
During a laparoscopic procedure, steps taken to reduce the risk of intraperitoneal spill include, most importantly, mobilization of the rectosigmoid posterior to the vagina; this allows for a lengthwise colpotomy, which easily will accommodate a 9- to 10-cm mass. For a mass that is larger than 10 cm, fixing it in the pelvis over the colpotomy and evacuating it vaginally using suction will minimize the risk of intraperitoneal spill. If rupture does occur, the peritoneal cavity should be irrigated copiously.
The most important factor that surgeons should keep in mind is that, even if laparoscopy is chosen to start a surgical procedure, and it is determined intraoperatively that complete staging is impossible, laparotomy, with an appropriate incision, can always be performed.
A Commonly Overlooked Problem
An oft-overlooked problem associated with the laparoscopic management of adnexal masses remains the overuse of this technology merely because it is “minimally invasive.” Indications for surgery should be no less stringent simply because we can now make smaller incisions with reduced patient morbidity.
Results of study by Nezhat et al are deeply troubling, in that 358 (35.5%) of 1,011 women undergoing either cystectomy or oophorectomy were found to have functional cysts. This differs markedly from the report of Spanos published almost 20 years previously, when laparotomy was reserved for patients in whom adnexal masses persisted after treatment with oral contraceptives. In that report, no patient undergoing laparotomy was found to have a functional cyst. This discrepancy is both hard to explain and quite worrisome.
Cristalli et al published the results of 108 patients undergoing either cystectomy or oophorectomy for persistent adnexal masses after an observation period of 6 weeks. Only 1 (< 1%) of 108 patients who underwent surgery solely for persistence was found to have a functional cyst. Functional cysts in the remaining patients were removed either emergently, secondary to hemorrhage or torsion in 20 patients (19%); or nonemergently, secondary to size (> 6 cm) in 6 patients (5.1%), pain in 4 patients (3.1%), or age in 1 patient (< 1%). These findings are more consistent with the earlier study by Spanos, and demonstrate how minimally invasive procedures can be integrated into the practice of gynecology.
Laparoscopically Assisted Radical Vaginal Hysterectomy
In discussing laparoscopically assisted radical vaginal hysterectomy (LARVH) and laparosocpic radical hysterectomy (LRH), Chi once again declares that both methods must be considered experimental “since neither method has been adequately studied, and only a few surgeons are qualified to perform either one.” To state that LARVH has not been adequately studied ignores the many studies published over the last 90 years in which radical vaginal hysterectomy was used to resect cervical cancer. Well over 2,000 cases have been described in the literature.[11,12] Modifying this procedure by performing the lymph node dissection laparoscopically or extraperitoneally, as Mitra described in 1954, hardly makes it experimental.
In Table 1, Chi demonstrates that minimally invasive approaches are associated with a reduction in blood loss, febrile morbidity, and hospital stay but have a worrisome complication rate, especially urinary and gastrointestinal tract injuries. However, this table uses a study by Averette et al as a basis of comparison but fails to cite a similarly large experience with radical vaginal hysterectomy by Navratil; this latter study reported a 1.2% rate of fistulas in 1,003 patients. The complication rates reported in relatively small studies, such as those by Hatch et al and Possover et al, should not be compared to rates in Averette et al as a means to highlight differences that may or may not be real.
Also, Chi also states that there are “many substantial questions” regarding the safety of this procedure. However, he fails to specify those substantial questions.
Issues that do remain to be discussed regarding the role of LARVH are its application in a population of decreasing parity and its potential for producing denervation of the bladder. In a study of 68 patients, Barclay and Roman-Lopez noted that the average patient required over 1 month of catheterization following LARVH. It has been postulated that this may occur more commonly in patients undergoing LARVH due to a more extensive resection of the parametria.
Laparoscopic Radical Hysterectomy
For obvious reasons, we agree with Chi regarding the potential advantages of LRH. Nevertheless, it should be noted that, at the Women’s Cancer Center, this procedure is used selectively in a manner similar to that employed in deciding whether to use a midline or low transverse incision.
It is also interesting to note that some surgeons, including many members of the Women’s Cancer Center, use endoscopic stapling devices to resect the parametria regardless of the surgical incision chosen. Fanning et al and Brewer et al reported a decrease in both operative time and blood loss when endoscopic staplers were used to perform radical hysterectomies.[14,15] It seems illogical to argue that the use of the same stapling device should be considered experimental only if used through smaller laparoscopic incisions.
It is an equally specious argument to state that since only a few surgeons are qualified to perform either LARVH or LRH, these procedures should be considered experimental. This level of surgical competency, even excellence, is achievable using minimally invasive techniques, and suggests that members of our specialty should continue to strive to develop these surgical skills. The recognition of the bell curve as it pertains to a surgical technique does not invalidate the procedure. If this logic were applied consistently, one would be forced to argue that should only a few surgeons master the techniques required to perform the traditional radical hysterectomy, it, too, should be considered experimental.
Adequacy of Laparoscopic Aortic and Pelvic Lymphadenectomy
In the most critical evaluation of a surgical technique to date, Schlaerth et al presented the results of GOG #9207, a study designed to determine the adequacy of laparoscopic aortic and pelvic lymphadenectomy in patients with early-stage cervical cancer at the 30th annual meeting of the Society of Gynecologic Oncologists in 1999. A total of 40 patients were evaluable. All patients underwent laparoscopic lymphadenectomy, and then the dissection was photographed. This was followed by laparotomy, at which time the accuracy of the laparoscopy, as well as the photographic evidence, was evaluated.
There was complete agreement regarding the adequacy of the aortic lymph node dissection. However, the pelvic lymph node dissection was found to be less than complete in 6 (15%) of 40 patients. In no patient was a positive lymph node left unresected.
The only site that was found to have residual nodal tissue was the area between the common iliac arteries and the psoas muscle, posteriorly down to the level of the lumbosacral nerve trunk. This area requires special care, given the irregular patterns of the pelvic veins draining into the hypogastric vein. In 85% of patients, all of the nodal tissue was resected from this area; therefore, it is logical to conclude that there was nothing inherent in the procedure that precluded resection of nodal tissue from this area.
It should also be pointed out that the adequacy of aortic and pelvic lymphadenectomy performed at the time of laparotomy has never been assessed. Photographic documentation has never been submitted to independent review, nor has a second surgeon tried to find more lymph node tissue following an initial dissection. Simply put, lymphadenectomy performed at the time of an open radical hysterectomy has never been subjected to such rigorous evaluation.
Schlaerth et al also reported vascular complications in only 2 (5%) of 40 patients (5%), based on GOG toxicity criteria, and urinary tract injuries in 1 (2.5%) of 40 patients. At laparotomy, urinary tract injuries were noted in 2 (5%) of 40 patients.
In patients with advanced cervical cancer, it is important to mention that in addition to undertaking an aortic and high common iliac lymph node dissection, the pelvic nodes should be assessed. If these nodes are positive, they should be resected, as recommended by Downey et al.
One of the most controversial issues regarding the use of laparoscopy that truly is unique to the technique may be trocar site recurrence in patients without intraperitoneal metastases. As this issue is unlikely to be addressed on a prospective basis, we have elected to use an endoscopic bag to collect such specimens prior to removal. In addition, in order to avoid entrapment of the specimen in the subcutaneous tissues, removal is recommended through a small colpotomy.
Minimally Invasive Surgical Techniques in Endometrial Cancer
Minimally invasive surgical techniques are used most often in the management of patients with endometrial cancer. Initial difficulty was encountered in resecting the left aortic lymph nodes, as Childers et al performed a bilateral dissection only in 12 patients.
The Women’s Cancer Center published the largest series of patients with endometrial cancer undergoing bilateral aortic lymph node dissection, as well as a cost analysis comparing patients with endometrial cancer undergoing traditional laparotomy to a group of patients undergoing surgery using minimally invasive techniques.[19,20] Laparoscopy was associated with decreased hospital stays, as well as lower pharmacy and overall hospital costs. Patient weight differed between the two groups, with the laparoscopy patients weighing less than those undergoing laparotomy.
As surgical experience has been gained, the upper limit as it pertains to weight as a function of height has risen steadily. Initial GOG trials limited patient accrual to those with a Quetelet index of less than 30. This was raised to 35 in later studies, and there is no weight restriction for entry into the randomized trial comparing laparoscopy to laparotomy in patients with endometrial cancer (GOGLAP 2) in which over 200 patients have been enrolled.
One of the more important applications of minimally invasive techniques is in the management of patients with incompletely staged endometrial cancer patients. Endometrial cancer accounts for nearly half of the gynecologic cancers on an annual basis. Not infrequently, patients with this cancer undergo simple hysterectomy without adequate staging.
In the recent GOG #99 trial, patients with endometrial cancer (stages Ia, Ib, or II) and negative lymph nodes were randomized to receive no further therapy or whole-pelvic radiation therapy. There was no difference in survival between the two groups. These data underscore the importance of completing surgical staging, as the results will have a greater impact on treatment than will knowledge of tumor grade or the depth of myometrial invasion.
Again, Chi concludes that even though Childers et al have demonstrated in a small series that laparoscopic staging can be completed safely and successfully in highly skilled hands, the value of the technique has not been confirmed. To the contrary, the value of this procedure is obvious, as it minimizes the estimation of the risk of metastases and thus allows therapy to be directed appropriately. Patients potentially can be spared both overtreatment and undertreatment.
The adequacy of minimally invasive surgery used in the treatment of patients with gynecologic malignancies has been documented by multiple investigators throughout the world. Even though endoscopic techniques and equipment have been adapted by surgeons performing radical hysterectomies via laparotomy, the minimally invasive techniques continue to be described as unproven by those without the skills to perform them. Undoubtedly, the learning curve for laparoscopic procedures is steep and the climb difficult, but that is not reason enough to characterize them as “experimental.”
For the past 5 years, the Women’s Cancer Center has organized the postgraduate course in minimally invasive surgery for the Society of Gynecologic Oncologists. Each year, at least one or two laparoscopic procedures have been undertaken “live” before a combined audience of approximately 250 gynecologic oncologists. The audience has been polled regarding the adequacy of these procedures, which have included LRH, LARVH, and pelvic and para-aortic lymph node dissection. At the completion of the procedures, there has not been one dissenting opinion regarding this issue among the course participants.
No other surgical technique has been examined in this setting or to this degree. The objective of minimally invasive surgery is not to replace laparotomy, but rather, to add one more weapon to our cache, one which would be used based on the individual surgeon’s skill and judgement and the patient’s condition. Within this framework, issues of safety should and will be defined.