Endoscopic lymphadenectomy

Practical Training and Research in Gynecologic Endoscopy

J. Salvat
Thonon Hospital, France

INTRODUCTION

A fundamental principle in the assessing the prognosis of many gynaecological cancers such as cancer of the breast, cervix and endometrium is to have information about lymphatic invasion. These tumours, which are the most common cancers in the world, spread predominantly by lymphatic channels. Cancer of the vulva and vagina are less common but also spread by lymphatic invasion.

Non-invasive assessment of lymphatic involvement is unreliable. Clinical examination of the axillary lymph nodes gives false results in one third of cases in breast caancer. Lymphography has a 80% sensibility in cervical cancer. Investigations such as CT scan and RMI are unreliable as predictors of lymph node involvement in the pelvis. Cytology gives as poor results although the reason for this is not clear. New biological markers are being investigated but the studies published so far ar too small to be significant.

Non-invasive techniques are useful in the initial investigation of the patient with cancer but only if they give positive results and in the assessment of surgical and anaesthetic fitness for surgery. The only reliable test of lymph node invasion is histological examination of the excised nodes and this remains the gold standard. Surgery has a part to play in therapy but the risk of complications is significant.

If lymph node biopsy is part of the planned surgical phase of treatment such as in Wertheim's hysterectomy or mastectomy, it is not necessary to perform preliminary lymph node biopsy. But if lymphatic lymph node biopsy is performed before conservative treatment or radio- or chemotherapy without surgery, endoscopic lymph node assessment is valuable.

The current trend is for the treatment of gynaecological cancer to evolve towards minimal access surgery for maximal benefit (2,3,4). In advanced lesions when treatment is to be by radio- or chemotherapy, endoscopic surgery gives information about lymph node involvement. Limited surgery such as vaginal hysterectomy is less aggressive with less risk of thromboembolism but gives no information about lymph node invasion.

In this chapter we review the investigation of lymph node invasion (5,6,7) in gynaecological cancer and, having reviewed the general basis and goals of treatment, we consider the technical conditions, procedures and limits for the investigation of lymph node invasion.

GENERAL BASIS

The accepted rules for the investigation and treatment of cancer and the principles of endoscopy must be respected. The prognosis will depend on the presence of metastatic carcinomatous cells within the nodes, the anatomy of the area and whether the ipsi-or contra-lateral nodes are involved.

Lymph nodes usually lie close to vessels, nerves and, sometimes, viscera. The endoscopist must be aware of the fine anatomy of the region. The vascular envelope is invaded late in the process of metastasis and, until invasion occurs, it is safe to remove the nodes. However, once the invasive process reaches the vascular tisssue, dissection is no longer possible and small biopsies are the only safe method of obtaining information. Nodes and lymphatic chains should be dissected en bloc to provide an accurate anatomo-pathological assessment. Parietal grafting may be necessary to cover the defect. Care must be taken with extraction of the specimen to avoid spillage of malignant cells - the lymphatic fluid in the node may contain metastatic deposits. Cutting lymph nodes is potentially dangerous for the same reason.

The endoscopic approach to lymph node dissection avoids opening the abdomen and offers greater safety with better visualization of the anatomy. The other advantages are the magnification offered by the lens and monitor and the diminution of blood loss resulting from the pressure of the distending gas.

GOALS

The results of endoscopic surgery must be at least as good as those from conventional surgery (4). The same number of nodes should be removed and the same outcome in terms of relapse-free survival time, local or regional recurrance, etc should be obtained. Additionally the post-operative recovery should be equivalent or improved.

GENERAL OPERATIVE ENDOSCOPIC CONDITIONS

1. Surgeon

A complete knowledge of the anatomy of the area is mandatory. The surgeon must be highly skilled and practice both endoscopic oncological surgery regularly. In many countries it is necessary to hold a certificate of accreditation in both formsof surgery (4). The contra-indications to surgery must be known and accepted. Facilities must be available to convert to open surgery in any complication or untoward incident arises.

2. Operating Room Team

The anaesthetist must be trained in endoscopic surgery. The patient should be intubated and hyperventilation may need to be continued post-operatively because the large volumes of CO2 used may induce hypercapny.

3. Nursing Staff

The nursing staff in the operating room (OR) and post-operative wards must be trained to care for these patients' special needs. This makes for greater efficiency in the OR and allows earlier recognition and consequent reduction of post-operative complications.

4. Equipment

All the OR equipment and instruments must be regularly maintained. in good working order. The instruments should include:

one 11mm trocar and cannula for the telescope
two 5mm trocars and cannulae for the dissecting instruments
one 10 or 12mm trocar and cannula for extraction of tissues.
a "Dargent's laparo-extractor" (Lepine Lyon, France) or a 5mm grasping forceps which can be inserted through a 12mm cannula.

5. Operating Procedure

The patient should be given a prophyllactic dose of antibiotics and her positioning on the OR table and the choice of anaesthetic should take into account the fact that the operation is likely to be prolonged. A final examination under anaesthesia should be performed, the results of pre-operative investigations should be checked to confirm the indications and limitations of the proposed procedure.

During the operation the anatomy of the region should be repeatedly checked to avoid risks and at all times bleeding should be avoided rather than controlled. Dissection should be gentle with good instruments and there should be good exposure before cutting or coagulating. All the dissected nodes should be extracted through cannulae because any remaining malignant tissue may produce metastatic deposits or be a focus for abscess formation.

At the completion of surgery a thorough check should be made of the whole operation field to ensure complete haemostasis. Suction drainage may be a useful precaution.

6. High Risk Patients.

Patients who are obese or have scars from previous surgery are unsuitable for laparosocpic surgery and such procedures must be avoided.

7. Pathological Examination.

Immediate pathological examination of all tissues is useful. The nodes must be numbered for identification and the source of each sample recorded to allow correct evaluation.

TECHNIQUES OF LYMPHADENECTOMY

It is prudent to recognise and differentiate usual, unusual and research procedures.

A. USUAL PROCEDURES

1. Pelvic Lymphadenectomy

1.1 Lymhadenectomy by panoramic retroperitoneal pelviscopy (Dargent-Salvat technique).

a Indications

This procedure is indicated for the exloration of the lymphatic chains of patients with pelvic cancer and mainly lateral lymphatic spread. This includes, in women, small (<4cm) cervical cancers, endometrial, vulval or vaginal cancer and, in men, prostatic (10) and bladder cancer.

Panoramic retroperitoneal pelviscopy is generally contra-indicated in large tumours, aggressive tumours with evidence of pelvic or lumbo-aortic spread detected by pre-operative CT scan.

b. Pre-operative management

Prophylactic antibiotics should be given, usually amoxicillin with clavulanic acid ("Augmentin"). The patient should be under general anaesthesia with endotracheal intubation and be placed in the dorsal position with a Trendelenberg tilt of 30 degrees. Side tilting may be advantageous. The usual antiseptic precautions should be employed, the abdomen should be covered with towels and the bladder catheterized.

c. Technique

The peritoneal cavity is accessed by a simplified "open laparoscopy" technique. A 2-3cm transverse incision is made three finger breadths above the os pubis. A "closed-open" scissor is inserted vertically in the subcutaneous tissue and a white aponeuretic cone is formed with two Kocher's forceps. Haemostasis is maintained with coagulation and compresses.

A tight purse string suture is placed round the aponeuretic cone with resorbable suture material. Its role is to prevent escape of CO2 gas. The aponeurosis is opened between the Kocher's forceps and a "closed-open" scissor introduced gently into the retroperitoneal space through the opening. The surgeon's fore finger is introduced in place of the scissors and pushed laterally guided by the iliac arch to reach the iliac vessels. It is possible to palpate abnormal, hard or enlarged lymph nodes. The retroperitoneal space is created. The peritoneum is gently separated from the internal surface of the rectus muscle by finger dissection from one side to the other. The laparoscope trocar with slieve covered by a rubber tube of the same diameter are gently introduced. The purse string suture is tightened around the slieve by applying tension on the threads using Kocher's forceps pulling on a small plastic sterile catheter. An alternative technique is to use a single-use tube with balloon which protects against escape of gas.

The laparoscope is inserted through the 10mm slieve and a general inspection of the retroperitoneal space is carried out. The CO2 pressure is maintained at 12mm Hg to aid pneumodissection but should be reduced to 8mm Hg after a few minutes to avoid hypercapnia.

Three secondary 5mm trocars and cannulae are inserted, two in the iliac fossae and one in the midline half way beween the umbilicus and the suprapubic transverse incision. It is important to prevent injury to the deep inferior epigastric vessels and other structures such as the great vessels and bladder. Three techiques may be employed to avoid epigastric vessel injury:

The vessels may be palpated with the surgeon's finger just after the retroperitoneal separation. The forefinger is used to elevate the posterior surface of the rectus abdominis and displace it medially when the vessel can be felt.
Transillumination of the abdominal wall allows the vessel to be visualized. The OR should be darkened and the vessels are seen by the light of the laparoscope.
The vessels may be seen through the laparoscope lying in the retro-peritoneal tissues.

After localization of the epigastric vessels the incisions are made for the 5mm cannulae in the iliac fossae and midline. Injury by the the trocars may be prevented by the surgeon's extended finger acting as a "stop" aided by direct visualization of the insertion. Three non-toothed forceps are introduced through the cannulae. One of the laterally placed forceps elevates and pushes the round ligament to open the para-umbilical tissues and gain access to the vesical fossa. The others may then be angled to work more efficiently. The "interiliac" lymph nodes are identified by the following landmarks:

the superior landmark is the external iliac vein which is blue, collapsed and medial to the pulsating artery.
the inferior landmark is the obturator nerve which is white
the anterior landmark is the posterior surface ofthe pubic bone
medially is the umbilical artery
posteriorally is the internal iliac artery.

If a pathological lymph node which is hard and enlarged is adherent to the vessels it should be biopsied using the "Tru-cut" system. If the lymph nodes are normal in appearance the dissection of the chain should continue. If the dissection is performed gently there is no need for haemostasis or lymphostasis. Any bleeding should be controlled with bipolar coagulation or stapling. Both pelvic side walls are dissected.

The lymphatic chains and lymph nodes should be extracted using "Dargent's coelioextractor" (Lepine, France). This instrument is like sugar tongs with three teeth. It can extract a complete lymphatic chain and nodes without allowing them to be in contact with the abdominal wall. Alternatively a 10mm cannula with reductor may be used. A 5mm forceps holds and extracts the lymphatic chain through the cannula.

At the completion of the operation haemostasis is checked, drainage is not usually necessary. The lymph chains and nodes are examined histo-pathologically in the OR.

There are advantages and disadvantages to this technique. The advantages are that the procedure is usually well tolerated by the patient, a good view is obtained of the lymphatic chain andvessels and post-operative adhesions are less frequent because the peritoneum is not opened. There are two major disadvantages. The first is that it is contra-indicated if there has been a previous laparotomy or Doleris-Pollenda technique. Secondly, the exploration is only of the iliac area and the peritoneal cavity, adnexa and other lymphatic chains cannot be seen.

d. Results

We have performed this procedure in 51 patients with cancer. The indications were:

Cervical cancer	46
T1a	16
T1b	18
T2	8
T3	3
T4	2
Endometrial cancer	3
Vaginal cancer	1
Ovarian cancer	1

The last case was misdiagnosed with metrorrhagia and a tumour with anamnesis of a closed vigina for prolapse.

Nodal Invasion

In our unit we performed 51 lymphadenectomies in 51 patients using panoramic retroperitoneal pelviscopy (PRP) between 24 January 1987 and 31 December 1995. The age range was from 35 to 80 years. Positive "interiliac" nodes were found in:

Cervical cancer	4 out of 46 cases
Endometrial cancer	1 out of 3 cases
Others	0 out of 2 cases

Complications

Five patients suffered complications in the series of 51 cases (10%). There were three peritoneal effractions and two patients had bleeding which did not necessitate laparotomy. There were four secondary complications: two patients had parietal secondaries caused by insufficient protection during extraction of tissues and two had abscesses requiring laparotomy. The late complications were three cases of lymphocysts (6%) treated by simple puncture. There were no cases of ureteric injury.

1.2 Laparoscopic Pelvic Lymphadenectomy

a Indications

The indications for laparoscopic pelvic lymphadenectomy are lymphatic exploration of pelvic cancers: cervical and endometrial cancer and laparoscopic preparation of extended radical vaginal hysterectomy (Shauta-Dargent technique).

b Contra-indications

The contra-indications are the same as the general contra-indications for laparoscopic surgery. Patients with ovarian cancer and those with evident lymphatic or distal metastases found on the standard investigations such as lymphography or CT scan are not suitable.

c. Pre-operative management

The patient should be under general anaesthesia with endotracheal intubation. The patient should be in the dorsal position with the thighs semi-flxed andin a 30 degree Trendelenberg tilt with lateral tilt also if necessary. The usual antiseptic techniques should be employed, the drapes should allow access to both abdomen and vagina and the bladder should be catheterized. Prophyllactic antibiotics are given.

d. Technique

Either open laparoscopy or the classical gas insufflation technique may be used. The pneumoperitoneum is created with a Veress' needle inserted through the umbilicus with the standard safety precautions. A 10mm trocar and cannula are introduced through an umbilical incision. Under laparoscopic control three 5mm secondary cannulae are introduced, one midway between the umbilicus and symphysis pubis and the other two lateral to the deep inferior epigastric vessels.

Washing cytology is performed with saline solution and the abdominal and pelvic cavities are examined. The main pelvic landmarks are checked: the umbilical artery, epigastric vessels, external iliac vessels, ureters and the ovarian vessels in the infundibulo-pelvic ligament.

The uterine cornu is grasped with toothed forceps and the peritoneum is carefully opened on the medial part of the round ligament by an incision directed antero-posteriorally. The incision extends lateral to the infundibulo-pelvic ligament which is pushed medially with the peritoneal flap.

The "interiliac" lymph nodes are identified by the following landmarks: the superior landmark is the external iliac vein which is blue and collapsed and lies medial to the pulsating external iliac artery. The inferior landmark is the obturator nerve which is white. Anteriorally is the posterior surface of the iliac bone, medially the umbilical artery and posteriorally the internal iliac artery.

The dissection begins lateral to the external iliac vein taking care to avoid the anastomotic vein from the obturator vein. If there is a pathological lymph node evidenced by it being hard, enlarged or adherent to the vessels, it should be biopsied using a "tru-cut" system. If the lymph nodes appear normal the dissection of the iliac chain is continued. The dissection is carried out gently without the need for haemostasis or lymphostasis. If there is bleeding it should be controlled with bipolar electrocoagulation or stapling. The lymph chain and nodes are extracted with Dargent's coelioextractor (Lepine, France) which removes the nodes without contact with the abdominal wall. At the completion of the operation haemostasis is checked, drainage is not routinely used. The lymph nodes are examined pathologically in the OR.

e Advantages

The surgeon uses standard laparoscopic visualization and not the less familiar retroperitoneal space. Laparoscopy allows inspection of the peritoneum, liver, adnexa and uterine body for evidence of malignant invasion and fluid can be aspirated for cytological examination. There is access to the complete lymphatic chains including the common iliac, presacral and lumbo-aortic.

It is possible to perform "web-ligament" preparation for extended vaginal hysterectomy. Ovarian transposition with oophoropexy ispossible in the premenopausal patient to protect ovarian function prior to radiotherapy. Lastly, the risk of lymphocyst formation is reduced because the peritoneal fluids can be drained.

f. Disadvantages.

The view of the lateral pelvic sidewall is not as good with a transperitoneal approach. The optic is above the lymphatic chains and vessels which hinders the view. There may be post-operative adhesion formation at the operating site if peritonization is not carried out properly. This may increase the risk to bowel from radiotherapy.

g. Results

Fifteen laparoscopic transperitoneal lymphadenectomies for cervical and endometrial cancer were performed in our unit between 1 January 1987 and 31 December 1985. Ten cases were treated by surgery alone which comprised exended vaginal hysterectomy by the Schauta-Dargent technique and five cases were explored only.

h. Complications

There were three immediate complications (20%). One patient had unexplained hypovolaemic shock but made a good recovery, two had laparotomy for bleeding during surgery. One of these had an injury to the obturator vein and the other had bleeding from the lumbo-aortic liament. There ws one bowel obstruction on the eigth day (6%) which was treated successfully by laparotomy.

1.3 Common Iliac Artery Lymphadenectomy

It is possible to explore the common iliac artery lymph chain after laparosopic pelvic lymphadenectomy. The view is limited by the aortic ligament which lies in front of the main vessels.

a. Indications

Common iliac lymphadenectomy is indicated in cases where the interiliac lymph chain has been invaded or to analyse the common iliac nodes.

b. Procedure

After opening the peritoneal fascia, the ureter and lumbo-aortic ligaments are pushed aside with non-toothed forceps to biopsy the lymphatic nodes. The two major risks are to the ureter and iliac veins. It is important to separate the veins from the artery to sample the nodes from the "Cueno et Marcille" fossa.

1.4 Presacral Lymphadenectomy

This is only possible after transperitoneal laparosocopic lymphadenectomy.

a. Indications

Presacral exploration is indicated in endometrial carcinoma, advanced cervical cancer or pelvic cancer.

b Procedure

The laparoscope should be inserted suprapubically and directed cranially. The surgeon is between the patient's legs. Care should be taken to avoid the superior haemorrhoidal and medial sacral arteries and the left common iliac vein

B. UNUSUAL PROCEDURE

1. Peri-aortic Lymphadenectomy

a. Indications

She indications for peri-aortic lymphadenectomy are cervical, endometrial or other pelvic cancer where there is suspicion of CT scan of lymph node invasion with negative cytology or "tru-cut" probe biopsy.

b Procedure

This should be performed either before (9) or after pelvic dissection. The patient is placed in the Trendelenberg position and the operator is between her legs. The laparoscope is inserted through the supra-pubic cannula and directed cranially. The Trendelenberg tilt allows the bowels to be displaced from the pelvis. The peritoneum is opened on the left side of the aorta. The ureters are pushed laterally with the peritoneal flap. The mesentertic artery is dessicated and the left lateral lymphatic chain is dissected using the upper landmark of the left renal vein to limit the dissection. The right side is dissected in the same way takin care to avoid the small precaval veins. The main risk is bleeding so both staples and suction should be available. This is not a procedure for the inexperienced surgeon and only those with ssuitableexperience or accredidation shoud consider undertaking aortic lymphadenectomy.

c Results

Dargent (1,3) and our team were the first to perform lymphadenectomy by retroperitoneal laparoscopy. Our first combined series of 100 cases of PRP were published in 1989 (1). Dargent has now performed over 400 cases. Reich described the first laparoscopic operations for ovarian cancer (6,11) and Schusler and Reich described the first cases of laparoscopic surgery for prostatic cancer (6, 10). They have now performed over 100 cases. Querleu was the first to describe the transperitoneal approach to the iliac lymph nodes (7). He reported 75 cases of pelvic and aortic lymphadenectomies. The operating time is between 60 and 120 minutes. Most of his cases (65) were cancers of the cerivx. He described the complications which included vascular injuries (1 mesenteric artery, 1 pelvic haematoma), 5 fibroses and 3 recurrences.

Childers reported 72 cases with 44 para-aortic endoscopic lymphadenectomies and 4 laparotomies in ovarian cancers (11). Sedlacek accepts that the ureter may be injured in these procedures (12). Fowler reported 12 cervical cancers treated laparoscopically and claimed better results as the learning curve was overcome (13). Spirtos reported 35 cases with an operating time of 3 to 7 hours (9). Twenty three of his cases were endmoetrial cancers and there was one injury to the inferior vena cava, two thromboses and some hernias through the 12 mm portals.

C. RESEARCH LYMPHADENECTOMY

1 Inguinoscopic lymphadenectomy (Dargent, 14)

a. Indications

The indications for this procedure are cancer of the vulva and the lower third of the vagina and cases of pelvic cancer where there are suspicious inguinal nodes.

b Procedure

A small median transverse incision is made which is 3 cm long and 3 finger breadths above the pubic bone. When the subcutaneous tissue is reached an infiltrating puncture is made with lipolyse solution (cf axillary disssection and sampling) over the suspicious inguinal nodes over 20 minutes. The inguinal area is suctioned for 10 minutes. using either a Karman curette or a plastic suction system. A trocar and cannula is inserted to carry the laparoscope. Two secondary 5 mm cannulae are inserted 5 cm apart and equidistant from the primary cannula. The inguinal area is explored and the nodes dissected and sampled. One of the 5 mm cannulae is replaced by a 10 mm cannula to allow the nodes to be extracted by a 5 mm forceps. Care should be taken to avoid the crural nerve and femoral vessels.

This procedure is especially useful because it avoids skin complications which are common in this area. Bilateral or retroperitoneal lymphadenectomy may be performed through the same incisions. Our own experience is limited to two cases, one of endometrial cancer with suspicious inguinal lymphadenopathy and one vulval cancer (Photo 12).

2. AXILLARY DISSECTION AND SAMPLING

Our technique is a variant of Suzannes procedure (15, 16).

a Indications

The indications for axillary dissection are breast cancer undergoing conservative treatment in all the quadrants except the upper external. In this condition it is simpler to carry out suction or direct node sampling.

b Infiltration

After removing the breast tumour and having histological confirmation of its malignancy the ipsilateral axillary area is infiltrated with a lipolytic fluid using a lumbar puncture needle and six 50ml syringes and after aspirating to prevent injection of the fluid into the blood stream. The lipolytic liquid consists of 350 ml isotonic saline, 150 ml distilled water and 2% solution of lidocaine with adrenaline. Suction is performed after 20 minutes of lipolysis and haemostasis by the liquid.

c Incision

The skin is incised at the point where a line through the equator of the breast crosses the anterior axillary line. The skin is opened through a Langer's line by a 2 cm incision.

d Aponeurosis opening

Open-closed scissors are inserted through the skin incision into the subcutaneous tissues and the clavi-pectero-axillary aponeurosis. The scissors are pushed in the direction of the infiltrated axillary pouch.

e Suction

The lipolyse suction systme with a negative pressure of 0.8 bar is used and suction continues ofr 10 minutes. A continuous nylon purse-string suture is inserted round the incision and the 10 mm laparoscope trocar and cannula is covered by a rubber tube to make the incision water tight. Carbon dioxide is insufflated at a pressure of 8 mm Hg. The laparoscope is inserted and the axillary cavity visualized.

f. Preparing dissection

Two 5 mm cannulae are inroduced into the axillary cavity under visual control. The incisions are made through avascular areas. The surgeon palpates the skin over the puncture site with the forefinger under visual control. Smooth probes are used to dissect and separate the different lymphatic chains and nodes while the important anatomical landmarks are identified: the great dorsal pedicle, latero-thoracic nerve and axillary vessels.

g. Dissection

Only the first and second levels of Berg are explored. A right handed surgeon holds monopolar scissors in the right hand and non-toothed forceps in the left to perform the dissection and split the lymphatic chains from the other structures. The nodes and chains are coagulated and cut.

h Extraction

The last step in the procedure is to extract the chains and nodes. This is done by replacing one of the 5 mm cannulae with a 10 mm cannula. The surgeon checks haemostasis but does not routinely insert a suction drain.

i Results

This technique allows the collection of nodes which are histologically evaluated. The aesthetic result is good. From 20 November 1994 to 1 January 1995 23 axillary dissections and sampling by suction under endoscopic control for breast cancer were performed in our unit. After the first 8 cases we randomised a series of 15 cases of endoscopic sampling with 15 cases of surgical sampling. The average number of nodes extracted was 12.7 in each series. The number of lymphocysts were the same and no serious complications occured in either series. The hospital stay was 3 days. The average duration of operating time was twwice as long for endoscopy (60 minutes vs 30 minutes) but the most important point was that the endoscopic patients were much more comfortable in the postoperative period.

We have recently had two recurrences of axillary node cancer. In both cases the cancers were very aggressive with poor prognosis signs. One had 22 invaded nodes out of 23 and the 3 out of 14. In neither case were the nodes clinically suspicious looking before sampling. After six and three months of chemotherapy respectively there were signs of axillary induration. Biopsy confirmed the recurrences.

Our practice has been modified when there is clinical suspicion or the histological examination of the nodes are positive. Direct surgical sampling is now used in these cases.

Future studies will investigate if lymphodema is diminished and if the risk of relapse is the same for endoscopic as for classical surgical sampling.

CONCLUSIONS

Endoscopic lympadenectomy is an advanced endoscopic procedure. It has proved to be an advance in investigating nodal involvement: there are advantages compared with conventional surgical procedures. The correct indications for endoscopic sampling need to be defined and the oncological results compared with surgical sampling.

These techniques are still experimental and need to be imporved and evaluated before their widespread use is advocated.