Prosthetic materials for abdominal wall reconstruction and hernia repair have been available to surgeons for repair of the groin and abdominal wall since the mid-twentieth century. Indeed, use of these materials by either an open or laparoscopic technique is the standard method of repairing incisional or groin hernia in most centers in North America and Europe. The first prosthetic materials used for hernia repair were synthetic meshes made of polypropylene or polyester.^1,2 They were introduced in an attempt to decrease the high risk of recurrent hernia observed in patients undergoing direct suture repair. Eventually, prospective randomized trials were conducted that demonstrated repair of even small incisional hernias without the use of mesh (primary closure repair) was associated with a significantly higher risk of recurrence (Figure 20-1), and nonmesh repair of all but the smallest abdominal wall defects was abandoned.^3,4,5

Initially, mesh repair of abdominal wall defects was accomplished by sewing the edges of the defect to the prosthetic material, which served to “bridge” the defect, much as a cloth patch repairs a defect in a garment (Figure 20-2). Although this was an improvement compared with primary closure, recurrence rates remained high. In the 1980s, surgeons in Europe and then in the United States began to place the mesh in a “sublay” position, allowing a generous underlay of mesh beyond the fascial defect, usually posterior to the rectus abdominus muscle of the abdominal wall (Figure 20-3). This placement utilized the physical forces of the abdominal wall and peritoneal cavity to hold the prosthetic in place, resulting in an effective repair, and dramatically lower rates of recurrence. An additional advantage of this technique, the “Stoppa” repair (named for Rene Stoppa, a French surgeon), was that the mesh was placed in an extraperitoneal position, essentially replacing the transversalis fascia in the pelvis or abdomen.⁶ In this setting bowel loops were not in contact with the mesh, and the risk of fistula and/or bowel adhesion and subsequent obstruction was minimized. In addition, the “Stoppa” or “Stoppa repair,” or giant prosthetic repair of visceral sac (GPRVS), was popularized in the United States by Wantz⁷ and could be applied to reconstruction of large groin hernias, particularly when bilateral or recurrent. This was accomplished by placing mesh in the extraperitoneal pelvis posterior to the pubis, anterior to the bladder, and extending into the iliac fossa bilaterally. Again, the extraperitoneal location of the mesh allowed a large sheet to be placed and minimized the potential for complications related to bowel adhesion to the mesh.⁸

The problem of bowel adhesion to synthetic mesh was further addressed with the development of “composite” synthetic meshes. These meshes were designed for placement within the peritoneal cavity with the parietal surface designed to minimize bowel adhesion. This development expanded the complexity of hernias that could be successfully repaired and facilitated hernia repair using minimal access techniques, which are almost exclusively intraperitoneal.

More recently, bioprosthetic implants have been created that are even less likely to cause adhesions or fistulas when placed in the peritoneal cavity. In addition, these materials can often be used to repair hernias or reconstruct the abdominal wall when bowel resections or contaminated procedures preclude the use of a synthetic mesh because the risk of infection is too high. They are expensive and associated with a higher risk of recurrent hernia, but if their use spares the patient a subsequent reconstructive operation, they are worth consideration at the time of oncologic resection.

The oncologic surgeon must have a fundamental understanding of reconstructive materials available for patients with abdominal wall defects. The decision to proceed with repair of these defects or to hold off has important implications for quality of life and cancer treatment, and these competing concerns require a knowledgeable and experienced surgeon or surgical team. Selection of the appropriate mesh or biologic implant for use is important to facilitate post-treatment recovery. A reasonable understanding of the advantages, disadvantages, and appropriate use of synthetic mesh and biologic implants will facilitate optimal care of these often complex surgical patients.

Abdominal wall reconstruction should be undertaken in most patients with structural defects undergoing radical cancer surgery. Clearly, if a patient is at high risk for infection secondary to gross contamination, excessive blood loss, morbid obesity, or some combination of high-risk clinical features, then delaying reconstruction may be more prudent. In most patients undergoing elective surgery; however, reconstruction of the abdominal wall or inguinal defect at the time of resection is preferable. Definitive repair of an incisional or groin hernia will add 1 to 3 hours to the operative procedure, depending on patient factors and prior surgical history. Done well, it can provide the patient with a significantly improved postoperative recovery and quality of life and avoid future operative procedures.

Preoperative Incisional Hernia

The most common clinical scenario faced by the gynecologic cancer surgeon is the patient who requires operation and has a preexisting incisional hernia. Consideration of repair after cancer resection should be made as part of preoperative planning. In most settings, repair can be safely undertaken, although the technique used and the type of prosthetic material placed requires considerable judgment. Although it is tempting to close a midline incision if it is feasible without the use of mesh, in a patient with an incisional hernia, recurrent hernia will almost always ensue.^3,4

1. Choice of prosthetic and surgical placement

Synthetic Prosthesis. Patients undergoing incisional hernia repair without large bowel resection, or with a ­limited small bowel resection, urinary tract procedure, or both can often be repaired with a synthetic prosthesis. Several examples of synthetic meshes for use in an extraperitoneal location are listed in Table 20-1. In addition, Vicryl (Ethicon, Johnson & Johnson, New Brunswick, New Jersey) mesh is listed, a slowly absorbable mesh composed of a polymer of glycolic and lactic acids, which can be used intraperitoneally as a temporary mesh to reconstruct the peritoneal sac or serve as a temporary repair when the use of a permanent mesh is too hazardous. Permanent synthetic meshes are used when the risk of mesh infection is low. The advantage of synthetic mesh is that it is associated with a significantly lower risk of hernia recurrence than a biologic implant. In addition, the cost of synthetic mesh is very low compared to a biologic implant. Synthetic extraperitoneal mesh is easy to work with and requires relatively few sutures to be placed in order to hold it in place. This is particularly true in pelvic reconstruction, where placement of a large sheet of synthetic mesh in the retropubic, extraperitoneal position with extension into the iliac fossa bilaterally (the Stoppa repair⁹) requires little fixation because the peritoneal sac holds the mesh in place with the patient in the upright position (Figure 20-4).

If used in the extraperitoneal position (ie, within the abdominal wall), then a lightweight polypropylene single layer mesh is ideal. These wide-weave meshes are less prone to shrinkage and may cause less sensation of abdominal wall stiffness compared to the traditional heavyweight standard weave polypropylene mesh. In patients with recurrent hernia, obesity, or other risk factors for recurrence, an ­intermediate weight polypropylene mesh is a reasonable choice and may provide more strength. Polypropylene or polyester mesh is always placed in an extraperitoneal location, so that the peritoneal sac must be closed in order to exclude bowel loops from the mesh and prevent bowel obstruction or fistula. Vicryl mesh (see Table 20-1) is a temporizing, absorbable mesh that can be used to reapproximate the peritoneum to exclude it from a permanent synthetic mesh. This is particularly true when the risk of adhesions is low, namely when the omentum is preserved, and when there has been no extensive adhesiolysis and the bowel has not been previously radiated.

Composite Mesh. When the repair is undertaken with a mesh within the peritoneal cavity, a composite mesh may be used (Table 20-2). The composite mesh is used in an intraperitoneal “underlay” position (Figure 20-5). Any intraperitoneal mesh must be secured to the undersurface of the abdominal wall with sutures placed circumferentially every 1.5 to 2 cm, to prevent interposition of bowel loops between the mesh or implant and the abdominal wall. If a composite synthetic mesh is used, then the parietal surface is composed of material designed to minimize bowel adhesion, while the side facing the abdominal wall promotes adhesion and adherence to secure the mesh and discourage mechanical displacement. There are many composite meshes available for use in hernia repair. Because they are more expensive than noncomposite synthetic mesh and must be secured with more suture fixation, they are almost always restricted to use in an intraperitoneal underlay repair. A few examples among many available products are listed in Table 20-2.

Biologic Implant. The third category of prosthetic that may be used for hernia repair and abdominal wall reconstruction is a biologic implant. These can also be used when patients are at very high risk for bowel adhesion to intraperitoneal composite mesh because of extensive adhesiolysis, prior radiation therapy, fistula, or omentectomy. Similar to composite mesh, biologic implants are designed for use within the peritoneal cavity. Biologic implants are composed of xenografts or allografts of acellular collagen and elastin that serve as a scaffold and allow for tissue ingrowth. Biologic implants come in different sizes, thicknesses, and have very different handling characteristics, and several examples are listed in Table 20-3. Because they promote capillary ingrowth and appear to be more resistant to infection, xenografts and allografts can be used in cases where a synthetic mesh may be considered too risky because of the potential for infection. Perhaps the greatest advantage of the prosthetics is that, if they do become infected, they often break down and are less likely to require explant, at least theoretically. Biologic implants take much longer to adhere to the patient’s abdominal wall, so that they rely on the mechanical strength of the suture and the positioning of the mesh to hold the implant in place. In addition, they must be used with great caution in patients who will require postoperative radiation therapy, as their safety in this setting is unknown.