What is pelvic exenteration?

In 1948 Brunschwig initially characterized this ultra-radical surgical procedure which is used in the treatment of pelvic exenteration, relapse or primary locally advanced pelvic cancer and that can be applied to the reproductive organs (ovaries, tubes, uterus, vagina in women; prostate and seminal vesicles in men), the lower urinary system (distal ureter, bladder and urethra) as well as for the removal  of rectosigmoid colon  as "en-bloc".

Embryological studies have revealed the concept of "morphogenetic unit". According to it, there are three units (compartments) in the pelvis that separate the urinary, genital and digestive system components from each other and have a common vascular mesentery and lymphatic drainage. The rectum, anus, and mesorectum originate from the "hindgut"; the “Mullerian morphogenetic unit” forms the fallopian tubes, mesosalpinx, uterus, mesometrium, proximal vagina, and paracolpium; whereas distal ureters, bladder, urethra and distal vagina develop from “urogenital sinus and Wolf ducts”. These separate units form a natural barrier against the spread of tumors from any organ to other structures. Current surgical guidelines prepared in line with compartment theory of Hockel and various oncological studies emphasize the importance of removing the entire involved unit (including the meso-viscera) along with the affected organ. Compartmented radical surgery requires en-bloc resection of the involved unit along with the affected organ. Ultra-radical compartmentalized surgery, which requires resection of more than one compartment, is the exact equivalent of pelvic exenteration.

In total pelvic exenteration, all of the pelvic visceral structures are removed together with some of the levator ani muscles that line the pelvic floor (infralevator) or without including the pelvic floor (supralevator), while the rectum and anus are preserved in anterior exenteration, whereas the bladder and urethra are preserved in posterior exenteration. The choice of procedural product depends on the location of the cancer, the difficulties encountered during surgery, the type and extent of previous radiotherapy, anatomy, and the patient's postoperative goals and expectations. Although this operation is mainly performed through the abdomen, there is also a perineal phase in cases where removal of the anus, urethra and vulva is required.
The current radical surgical concept may also include nonanatomical resections to achieve complete (R0) resection and has expanded to include the sacrum in posterior compartment resection and the pubic bone in resection of anterior compartment tumors (composite pelvic exenteration). In addition, lateral spread of the pelvic tumor may sometimes require resection of the lateral compartment (LEER), which includes the vascular, neurogenic, and muscular structures of the pelvic sidewall. However, such surgeries are used in very selected cases and very rarely.

In which tumors and for what purpose is it applied?

Although pelvic exenteration was initially widely used for the palliative treatment of relapsed cervical tumors, over time it has taken its place as the salvage treatment of many recurrent or primary locally advanced pelvic cancers. Today, it is frequently applied in cervix, rectum and bladder cancers that have relapsed (without pelvic side wall coverage) after radiotherapy, but this procedure can also be applied in some other cancers such as uterine tumors (including sarcomas), vulvo-vaginal cancers, prostate cancers and rhabdomyosarcoma. Although it is now rare with modern technologies, severe radiation necrosis (without tumor) can also be an indication for exenteration.

Patients with ovarian cancer are not ideal candidates for exenterative surgery, as the disease often causes a peritoneal spread beyond the pelvis and survival rates after exenteration are not satisfactory. An exception to this is; as a part of primary and secondary cytoreduction interventions, “modified posterior exenteration”, in which the pelvic peritoneum, uterus, tubes, ovaries and rectosigmoid are resected en-bloc together with the tumor, is a highly effective procedure that contributes significantly to survival.

Pelvic exenteration surgery is a potentially curative surgery. Although sometimes applied for palliative purposes to relieve persistent pain, fistula, bleeding, sepsis, obstruction, etc., symptoms and clinical conditions (some of which may be related to previous radiotherapy), such use of exenterative surgery is highly controversial. Despite an average survival of 14 months when used for palliative purposes, morbidity, complications, risk of death and prolonged hospital stay associated with the procedure are too high for a palliative approach. Surgical judgment and common sense should be used in selecting patients who can tolerate palliative surgical procedures without excessive morbidity and are likely to benefit from the additional life span  that the operation could potentially provide.

 

What are the application criteria (indications)?

Pelvic exenteration is the last hope of curative treatment for a patient with resectable disease. When the patient is selected with the right criteria, the procedure can be completed successfully in two-thirds of the patients. Although perioperative mortality and morbidity are high (about 5% and 50%, respectively), it provides an average of 50% chance of survival of 5 years. Maximum  experience is in recurrent cervical and rectal cancers in the central pelvic region and the best results are obtained with these tumors.

For patients with a confirmed pathological diagnosis, the first criterion for pelvic exenteration is the absence of other treatment options including radiotherapy and very limited surgical options. Next, it should be demonstrated clinically and radiologically that the disease  has not metastasized and  is limited to the pelvic area, with the possibility of complete (Ro) resection. Furthermore, the general condition of the patient must tolerate the surgery and subsequent chemotherapy. Finally, there should be an experienced surgical team and proper hospital conditions that can perform the surgery, provide optimal post-operative care and manage the problems that may arise.  

   

What are the inconvenient situations (contraindications) for application?

Absolute and relative contraindications for pelvic exenteration have been described in the literature.

Absolute contraindications:

• Peritoneal metastasis
• Skip metastasis in the intestine
• Paraaortic region lymph node involvement
• Lumbar and Sacral 1-2 bone involvement
• Other distant site metastases (eg, liver, lung, bone, etc.)

Relative contraindications:

• Direct invasion into adjacent intestinal segment
• Pelvic lymph node involvement
• Bilateral hydroureter or hydronephrosis
• Pelvic side wall involvement
• Very high dose (>6000cGy) radiation
• Morbid obesity

The presence of a “triad” in the form of leg edema, ureteral occlusion and leg pain as a pathognomonic clinical evidence of progression of the disease to the pelvic side wall (side wall involvement) is generally considered a contraindication for surgery, still in such cases some surgeons perform even more radical surgeries such as LEER (laterally extended endopelvic resection), which involves resection of the pelvic lateral structures in which the skeletal muscles, nerves and vessels are located.

However, further research is needed for the indications and results of such procedures. We do not resort to such complicated and high morbidity surgeries in patients with clinical or radiological (MRI and/or CT angiogram) evidence of pelvic  lateral wall involvement.  

 

What is the contribution of exenteration to life expectancy?

Exenteration increases the 5-year survival rate, which is around 5-10% with standard treatments, to an average of 50% (24-77%) in patients with recurrent pelvic cancer. 

 

What are the risk factors for disease recurrence after exenteration?

The most important factor predicting recurrence, survival and quality of life is Ro resection (at least 1 mm negative/clean resection margin at surgery). Therefore, clean surgical margins are crucial for recurrence prevention and the chance for long-term survival.

Risk factors for recurrence and poor prognosis:

• Surgical margin positivity (R1 resection)
• Tumor diameter ≥ 5 cm
• Pelvic lateral wall involvement
• Lymph node metastasis
• Time elapsed since previous radiotherapy <1 year.

 

What tests and preparations are made before exenteration?

After histological confirmation of the disease is provided and the exenteration option is considered, some tests and examinations should be performed in order to prepare for the operation as well as determine whether the patient is resectable and if patient can tolerate this multivisceral surgery, which has a major risk of morbidity with serious body image and lifestyle changes.  

Tests and examinations include:

• Imaging tests: high resolution pelvic MRI, PET/CT (or conventional CT), CT arteriography, venogram (to exclude distant metastasis and pelvic sidewall involvement)
• Endoscopies: cystoscopy, rectosigmoidoscopy (RSS)
• Vaginal/rectal examination
• Central vascular access
• TPN (parenteral nutrition) in malnourished patients
• Lab tests: Hemogram, liver and kidney function tests, albumin, ions, bleeding-coagulation tests, tumor markers
• Correction of anemia and neutropenia (if any)
• Evaluation of cardiac and respiratory reserve (+cons?)
• Anesthesia examination
• Preparation of surgical team, materials and instruments
• Preparation of 6 units of ERT and 2 units of plasma
• Mechanical bowel preparation (day before surgery and concurrent with iv fluid replacement)
• Teaching the use of incentive spirometry
• Determination of stoma location
• Meeting with the enterostomal therapist
• Physiotherapy planning (for the post-operative period)
• Evaluation of psychosocial status
• Informed consent

 

In which cases is radiotherapy (IORT) added during surgery?

Although intraoperative radiotherapy (IORT) is not routine application, health centers with this possibility apply the method to increase treatment efficacy. It is especially applied in case of close surgical margin.

 

How many hours does the operation take? Is intensive care required?

Exenteration surgeries take up to 5-12 hours (average 8 hours) and often require an intensive care period (sometimes long-term).

 

How long is the hospital stay and recovery period after exenteration?

The hospital stay ranges from 1 to 6 weeks, with an average of 14 days. Such  extended  hospital stays are due to complications.

 

What are the short- and long-term complications of exenteration surgery?

In the first years of application, surgical related death rate was 23%. Today, this rate is around 3-5%, thanks to the advancement of surgical techniques (eg, the use of staples, the creation of a separate urinary conduit, pelvic reconstructions, etc.) and developments in areas such as intensive care, antibiotics, parenteral nutrition and thrombosis prophylaxis. Complications develop in 30-80% of patients, and more than half of these are major complications that will require diagnostic or therapeutic intervention. Complications can be non-specific or specific and sometimes become more prognostic than the underlying disease.

Common non-specific complications:

• Bleeding
• Venous thromboembolism
• Infection-abscess-sepsis
• Respiratory/multiorgan failure
• Anastomotic leaks: 30-50% in the lower rectal anastomosis
• Paralytic ileus, intestinal obstruction
• Wound opening (dehiscence)
• enteric fistula
• Stoma necrosis and separation
• Late stoma problems (skin problems, stenosis, prolapse, hernia)

Specific complications are mostly due to urinary conduit, “empty” pelvis, or problems with pelvic reconstruction.

Common specific complications:

• Evisceration of visceral organs from the perineum (due to an “empty” pelvis)
• Pelvic abscess (due to “empty” pelvis)
• Intestinal obstruction/fistula (due to “empty” pelvis)
• Ischemia, necrosis and infection in myocutaneous (TRAM, gracilis etc.) flaps
• Urinary (ureteral) leak
• Ureteral stricture or obstruction
• Renal stone formation
• Recurrent pyelonephritis
• Urine reflux, hydronephrosis and renal failure

 

Who does exenteration surgery? What type of hospitals should the surgery be performed in?

Pelvic exenteration surgery should be performed by Surgical Oncologists experienced in pelvic and abdominal surgery. However, contributions of other surgeons from various specialties (eg, plastic surgery, vascular surgery, orthopedic surgery, neurosurgery, etc.) may be needed within the scope of multidisciplinary work. This type of surgery can only be performed in well-equipped, well-organized hospitals with advanced intensive care facilities.

 

Is chemotherapy or radiotherapy applied following exenteration?

Re-irradiation is a rarely used method since most patients would have already received radiotherapy before. However, chemotherapy and other systemic treatments (smart drug, immunotherapy) are often required.

 

What are the treatment options in cases where exenteration cannot be applied?

In this case, patients mostly receive palliative/supportive treatments. In some cases, limited benefit may be obtained from palliative chemotherapy.

 

What should be the approach if the disease recurs after exenteration?

Relapses occur mostly in the pelvis area, and this group of patients may have a small chance of re-operation. Remote site recurrences are often candidates for palliative/supportive treatments (including palliative chemotherapy).

 

Is the bag (stoma) permanent after exenteration?

After exenteration, there are usually two stomata, one of which is the “neo-bladder” (ileal reservoir that functions as the new bladder) and the other belongs to the sigmoidostomy, and both are permanent.

 

Is exenteration surgery expensive? What is the cost?

Exenteration surgery is an expensive surgery. According to “PelvEx Collaborative” data, “ 8-hour operation + two-night intensive care + 14-day hospitalization (without interventional radiological procedure, reoperation and orthopedic/vascular/plastic instrumentation or intervention) was reported to cost approximately $55,000. There is an additional amount of approximately $2500 for each added day of intensive care and approximately $600 for each additional standard hospital stay. Further expenses can be expected as around one third of the patients encounter major complications that might require extra procedures like imaging studies, interventional radiological procedures, and re-operation. Contrary to the global data mentioned above, we can perform exenterative surgeries for far more affordable costs in our country.