Patients treated by drug instillation into the abdomen or pelvis uniformly have had prior surgery, which causes scarring. The adhesions create multiple barriers to the free access of fluid. Although the instillation of a large volume of fluid will partially overcome the problems created by adhesions, frequently large surface areas will have no access to chemotherapy. In addition, limited access from adhesions may increase with repeated instillations of chemotherapy. Tumor cells may be protected not only by adhesions, but also by surface sear.
Surgery results in fibrin deposits on surfaces that have been traumatized by the cancer resection.
Free intraperitoneal cancer cells become trapped within the fibrin. The fibrin is infiltrated by platelets, neutrophils and monocytes as part of the wound healing process. As collagen is laid down, the tumor cells are then entrapped by scar tissue. The scar tissue is marginally vascularized by either intravenous or intraperitoneal chemotherapy. There has been no technical solution to the requirement for reliable repeated access to the peritoneal space.