Wound Implantation Research Articles

INDICATIONS AND CHOICE OF TECHNOLOGY FOR POLYMERIC MATERIALS IMPLANTATION IN THE ABDOMINAL WALL FOR PREVENTION AND TREATMENT OF POSTOPERATIVE VENTRAL HERNIAS

The absolute indication for primary covering a laparotomic wound with a synthetic prosthesis is complicated anatomic and functional insufficiency. There are relative indications for this surgery, such as old age, III–IV degree of obesity, repeated laparotomy in location of the same scar, covering a laparostoma in patients treated with programmed sanation of the abdominal cavity and laparotomy in patients treated with radiology or chemotherapy methods. Lowering of functional activity of ribosomal genes is a reason of the anterior abdominal cavity weakness, its progress causes lowering in skin and aponeuroses composition I–III types of collagen. We examined the speed of growing and differentiation of connective tissue after implantation endoprosthesis made of lavsan, polypropylene, polyvinylidene fluoride, polytetrafluoride ethylene. It was proved that the polyvinylidene fluoride mesh had the best biocompatibility. The progress of wound implantation process could be predicted by dynamics of cytokine profile, temperature, leukocyte and exudative reactions of a patient. The best insensitiveness to infection belonged to a standard polypropylene endoprosthesis, it could be used for covering a hernia defect in patients with strangulated hernias. The fact that urine poured into the operation wound during urinary system surgery combined with lateral hernias of abdomen was not a contraindication for endoprosthesis.

Wound Healing Angiogenesis: Innovations and Challenges in Acute and Chronic Wound Healing

Formation of new blood vessels, by either angiogenesis or vasculogenesis, is critical for normal wound healing. Major processes in neovascularization include (i) growth-promoting or survival factors, (ii) proteolytic enzymes, (iii) activators of multiple differentiated and progenitor cell types, and (iv) permissible microenvironments. A central aim of wound healing research is to "convert" chronic, disease-impaired wounds into those that will heal. Reduced ability to re-establish a blood supply to the injury site can ultimately lead to wound chronicity. (1) Human fetal endothelial progenitor cells can stimulate wound revascularization and repair following injury, as demonstrated in a novel mouse model of diabetic ischemic healing. (2) Advances in bioengineering reveal exciting alternatives by which wound repair may be facilitated via the creation of vascularized microfluidic networks within organ constructs created ex vivo for wound implantation. (3) A "personalized" approach to regenerative medicine may be enabled by the identification of protein components present within individual wound beds, both chronic and acute. Despite the development of numerous therapies, impaired angiogenesis and wound chronicity remain significant healthcare problems. As such, innovations in enhancing wound revascularization would lead to significant advances in wound healing therapeutics and patient care. Insights into endothelial progenitor cell biology together with developments in the field of tissue engineering and molecular diagnostics should not only further advance our understanding of the molecular mechanisms regulating wound repair but also offer innovative solutions to promote the healing of chronic and acute wounds in vivo.

In VitroElution of Amikacin and Ticarcillin from a Resorbable, Self‐Setting, Fiber Reinforced Calcium Phosphate Cement

To determine in vitro elution characteristics of amikacin and ticarcillin from fiber reinforced calcium phosphate beads (FRCP). Experimental. FRCP beads with water (A), amikacin (B), ticarcillin/clavulanate (C), or both amikacin and ticarcillin/clavulanate (D) were bathed in mL phosphate-buffered saline (PBS) at 37°C, 5% CO(2) and 95% room air. PBS was sampled (eluent) and beads were placed in fresh PBS at time points 1 and 8 hours and 1, 2, 3, 4, 5, 6, 7, 10, 12, 14, 18, 21, 25, 28, 35, 42, 49, and 56 days. Antibiotic concentration and antimicrobial activity of eluent against Escherichia coli, Staphylococcus aureus, and Klebsiella pneumoniae were determined. Both antibiotics eluted in a bimodal pattern. Beads with a single antibiotic eluted 20.8 ± 2.5% of amikacin and 29.5 ± 0.8% of ticarcillin over 56 days. Coelution of the antibiotics resulted in a lower proportion (AUC(0-∞) ) of antibiotics eluted for both amikacin (9.5 ± 0.2%) and ticarcillin (21.7 ± 0.09%). Bioassay of antimicrobial activity of the eluent (t = 1, 8, and 24 hours) established reduced antimicrobial activity of amikacin from combination beads (D). FRCP beads with amikacin or ticarcillin/clavulanate, but not the combination, are suitable carriers for wound implantation. Duration before complete resorption of FRCP beads in vivo should be determined before clinical use as a resorbable depot. The results of this study underscore the importance of testing drug combinations, despite success of the combination systemically, before their use in local applications.

SiRNA-Mediated Reduction of α-Actinin-1 Inhibits Pressure-Induced Murine Tumor Cell Wound Implantation and Enhances Tumor-Free Survival

Viable cancer cells can commonly be recovered from surgical sites and venous blood during tumor resection. The adhesion of these cells to surrounding tissues may impact patient outcomes. Iatrogenic exposure to increased extracellular pressure modulates integrin binding affinity and stimulates colon cancer cell adhesion in vitro through an α-actinin-1-dependent signaling pathway. We hypothesized that preoperative small interfering RNA-mediated silencing of α-actinin-1 in tumor tissue could disrupt pressure-stimulated cancer cell adhesion to murine surgical wounds and thereby enhance subsequent tumor-free survival. Reducing α-actinin-1 in CT26 murine adenocarcinoma cells blocked cell adhesion to collagen in vitro and similarly inhibited pressure-induced CT26 implantation in murine surgical wounds in vivo. Surgical wound contamination with pressure-activated CT26 cells significantly reduced tumor-free survival compared to contamination with tumor cells maintained under ambient pressure. However, mice treated with pressure-activated CT26 cells preoperatively transfected with α-actinin-1-specific small interfering RNA displayed reduced surgical site implantation and increased tumor-free survival compared to mice exposed to pressure-activated cells expressing normal levels of α-actinin-1 protein. These results suggest that pressure activation of malignant cells promotes tumor development and impairs tumor-free survival. α-Actinin-1 may be an effective therapeutic target to inhibit perioperative pressure-stimulated tumor cell implantation.

A rare case of isolated wound implantation of colorectal adenocarcinoma complicating an incisional hernia: case report and review of the literature

BackgroundThe reported case illustrates an instance of colonic adenocarcinoma presenting as an isolated tumour 3 1/2 years after open surgery. The presentation was in some respects unique as it was complicated by an incisional hernia and occurred in the anterior abdominal wall. A literature review was performed.Case presentationAn 83 year old lady initially underwent an extended right open hemicolectomy for a mid-transverse colonic adenocarcinoma (T4N2M0). No adjacent structures were involved. After adjuvant chemotherapy, she was kept under regular surveillance. A CT scan and colonoscopy at one year were normal. At 18 months investigations including an ultrasound scan of the liver and a radioisotope bone scan were all negative. Over three and half years later the patient presented with an incisional hernia. Repeat CT scan and tumour markers were reported as negative. At operation, a mass was found within the anterior abdominal wall complicating the incisional hernia. This mass was widely resected and a laparotomy performed. Histology confirmed an adenocarcinoma of colonic origin extending to one of the lateral margins. A post-operative PET scan confirmed the absence of intra-abdominal pathology.ConclusionThe literature regarding recurrence of colonic tumours after open surgery reports low incidences of this occurring within abdominal incisions. The literature indicates prognosis is poor, but the numbers are small and distinction is often not made between isolated recurrence and those with other sites of tumour recurrence. In order to avoid missing isolated wound implantation, careful consideration should be given to those who present with new pathology related to previous cancer surgery incisions, both clinically and radiologically.

Wound implantation—a surgical hazard

A review of the literature on wound implantation together with a report on an unusual case of implantation of squamous carcinoma at the site of a gastrostomy is presented.

Environmental Factors of Temperature, Humidity, Serum Accumulation, and Cell Seeding Increase Colon Cancer Cell Adhesion in Vitro, with Partial Characterization of the Serum Component Responsible for Pressure-Stimulated Adhesion

Physical characteristics of surgical wounds and viable tumor cells shed may differ between open and laparoscopic procedures. Because environmental factors may vary between the laparoscopic milieu and that of open surgical procedures, we sought to characterize the effect of these factors on tumor cell adhesion, an early step in the process of wound implantation. Human SW620 colon cancer cells were placed in matrix-precoated dishes for 30 min at concentrations of 90,000–540,000 cells/well, at 25–37°C, in the native state of the matrix proteins and after drying for 60 min, and in 0–10% serum. As increased pressure has previously been reported to stimulate colon cancer cell adhesion synergistically with serum, we then further partially characterized the serum components responsible for this potentiating effect. The number of adherent cells varied linearly with cells seeded. Adhesion was temperature-dependent, and also was dependent on the matrix conformation. Less adhesion occurred to dry matrix proteins. Serum dose-dependently potentiated SW620 pressure-stimulated adhesion, with a maximal increase in adhesion compared with ambient pressure conditions at 5% serum concentration. Heat inactivating the serum at 60°C for 30 min ablated the effect. Filtration to remove molecules over 10 kDa produced no change in adhesion relative to ambient conditions, but filtration to 100 kDa preserved the serum effect. When the serum was passed over a gelatin-Sepharose column, which binds numerous proteins including fibronectin, the serum effect was lost. Addition of fibronectin to serum-free media did not reconstitute the effect. The environmental factors of warm temperature, moisture, and serum accumulation may contribute to increased colon cancer cell adhesion. However, the most important determinant of malignant adhesion to surgical wounds, laparoscopic or open, is likely to be the size of the tumor cell inoculum. Pressure stimulation of colon cancer cell adhesion is potentiated by heat-labile serum components of molecular weight 10–100 kDa which bind gelatin-Sepharose, and is not fibronectin alone. Irrigating serum from surgical wounds may decrease tumor implantation.

Intraoperative saline and gemcitabine irrigation improves tumour control in human squamous cell carcinoma-contaminated surgical wounds.

The cure rates for advanced head and neck cancer patients have not changed substantially in the past few decades. Most disease recurrences are local or regional and are likely due to residual microscopic disease or intraoperative wound contamination. We developed a murine model of wound implantation with microscopic disease to assess the efficiency of tumour development and used this model to evaluate the effects on tumour development of surgical bed irrigation with three different solutions. Nonobese diabetic/severe combined immunodeficient mice were transplanted with the University of Michigan squamous cell carcinoma-22B cells derived from a human squamous cell carcinoma of the hypopharynx. Two 1-cm surgical wounds were created on the backs of 20 mice and then instilled with a known quantity of tumour cells. The minimum necessary dose to reliably result in tumour growth was then determined. Forty mice were then inoculated with this minimum tumour concentration. Ten of these mice had their incisions closed immediately and were kept as controls. Ten of the mice had their wounds irrigated with 5 cc of water and then closed, 10 had their wounds irrigated with 5 cc of saline and then closed, and 10 had their wounds irrigated with 5 cc of 1-mM gemcitabine, a nonirritating chemotherapy drug with activity in human head and neck cancers. The mice were then observed for the development of palpable tumours. We were unable to successfully grow tumours in any wounds that were seeded with less than 2.5 x 10(6) cells. After exposure to 2.5 x 10(6) cells, seven of eight surgical beds developed palpable tumours. This was then taken as our standard inoculation dose. All of the study mice wounds healed rapidly irrespective of irrigation solution. At postoperative day 17, 70% of the controls had evident tumour growth, whereas only 15% of the water irrigation group (p < .0005), 0% of the saline irrigation group (p < .0001), and 0% (p < .0001) of the gemcitabine irrigation group had developed tumours. By day 24, the disease recurrence rates in the water irrigation group no longer differed from controls, whereas the lower incidence of tumour recurrence in the gemcitabine and saline irrigation groups persisted. On day 56, 80% of the control mice and 75% of the water-irrigated mice group had developed palpable tumours. In the saline and gemcitabine groups, however, only 40% (p < .01) and 35% (p < .004), respectively, had evident tumours. In a xenograft model of tumour-cell wound contamination, irrigation with saline, water, or gemcitabine delayed tumour development. Irrigation with gemcitabine or saline improved rates of long-term disease control. Gemcitabine irrigation did not affect wound healing and was free of local complications.

Influence of trocar placement and CO(2) pneumoperitoneum on port site metastasis following laparoscopic tumor surgery.

The mechanisms involved in the development of port site metastasis following laparoscopic tumor surgery remain controversial. Therefore, we decided to investigate the influence of trocar placement and CO(2) pneumoperitoneum on abdominal wound implantation in relation to intraperitoneal tumor growth in a rabbit model. Rabbits received either CO(2) pneumoperitoneum with insertion of nine trocars (pneumoperitoneum group, n = 15), insertion of nine trocars alone (nonpneumoperitoneum group, n = 15), or nine abdominal incisions (control group, n = 13) 3 days after intraperitoneal inoculation of VX(2) cancer cells. The frequency of overall wound implantation on day 17 in the pneumoperitoneum group (24.4%) and nonpneumoperitoneum group (27.4%) tended to be higher than that in the control group (15.3%) (p = 0. 06). There was no significant difference among the three groups in the growth of cancer nodules on the omentum. The presence of a trocar may be a factor contributing to port site metastasis but CO(2) pneumoperitoneum appears not to be a factor.

Abdominal insufflation does not cause hematogenous spread of colon cancer.

Previous investigators have suggested that port-site recurrences are possibly a result of abdominal insufflation, forcing viable cancer cells into the circulation to metastasize and thrive in areas of trauma. Using a syngeneic animal cancer model, we tested the hypothesis that pneumoperitoneum increases the incidence of wound metastasis by a blood-borne mechanism. Male BD IX rats (N = 150) were injected intraperitoneally with 2 x 10(5) viable syngeneic 1,2-dimethylhydralazine-induced colon cancer cells (DHD-K12). Animals were divided into three groups: A (abdominal insufflation with 3-cm incision on the back into muscle remote from the peritoneum); B (3-cm back incision alone); and C (control group with 3-cm midline abdominal incision). Three weeks after surgery, the animals were euthanized and autopsied. In the two groups with back wounds, the incidence of cancer growth at the incision was zero, as demonstrated grossly and by histologic sample (A: 0/47, B: 0/43). In contrast, the autopsied control group had a 42% incidence of metastasis to the wound (25/59). There seemed to be no difference in the distribution of intra-abdominal disease between those rats that underwent insufflation and those that did not. It is unlikely that pneumoperitoneum promotes hematogenous wound implantation of free intraperitoneal cancer cells.

Is the port site really at risk? Biology, mechanisms and prevention: a critical view.

Early case reports of port site tumour implants led to debate regarding the appropriateness of laparoscopic techniques for abdominal malignancies. Review of clinical, animal and cell culture studies addresses the relationships between tumour staging and shed cell behaviour that contributes to the peri-operative spread of tumours. In addition, a porcine model was used to test tumour cell distribution after laparoscopic and open colonic resections. Clinical evidence indicate that wound recurrence rates are 0.60 and 0.85% for open and laparoscopic colon cancer operations, respectively. Tumour staging and operative techniques are the most important factors determining wound implantation. Port site and open wounds are at equal risk of tumour implantation.

Tumour cell wound distribution after colectomy in a porcine model.

Concerns over tumour implants have impeded the adoption of laparoscopic surgery for cancer. Explanations assume an increased number of malignant cells present in trocar wound sites. The following are tested in the present paper: (i) that the magnitude of wound contamination following surgery is related to the location of the tumour cells; and (ii) the surgical approach. We have used a porcine sigmoid colectomy model to compare the number of tumour cells on laparoscopic wounds after resections in the presence of intraluminal, intramural and intraperitoneal 51Cr-labelled, fixed HeLa tracer cells. Open colectomies were also performed in the presence of intraperitoneal tracer cells and their numbers on laparotomy wound surfaces were determined by gamma counting. With intraperitoneal cells, laparotomies had 1087 (+/- 106) tracer cells per mm (n = 4) while trocar wounds had 103 (+/- 54) cells per mm (n = 10) (P > 0.05). Resection of intramural tumours resulted in lower trocar wound contamination (0.9 +/- 0.6 cells/mm, n = 3). Resection of colon including intraluminal tracer cells resulted in 2.9 +/- 2.1 cells/mm on trocar wounds (n = 3). More tumour cells were deposited on open than laparoscopic trocar wound surfaces. Also, the risk of wound implantation is less with intraluminal or intramural tumours than with intraperitoneal cells (P > 0.05).

Abdominal incision tumor implantation following pneumoperitoneum laparoscopic procedure vs. standard open incision in a syngeneic rat model.

A recent hamster model study suggests that the abdominal wall wound implantation rate increases following laparoscopic colon cancer surgery compared with the traditional open technique. However, results of that study were confounded by several factors, including a midline incision in the laparoscopy group, an unclear definition of wound implantation, significant age variations in study subjects, and cell line use with low viability. The aim of this study was to compare the abdominal incision implantation rates following a pneumoperitoneum-laparoscopic-type procedure with a standard open incision using a syngeneic host/colon cancer rat model. Viable DHD/K12 rat colon carcinoma cells (2 x 10(5) cells/rat) were injected intraperitoneally via 18G angiocath into anesthetized, immunocompetent BD-IX rats (syngeneic host rats). Rats were then randomly divided into open incision and laparoscopy groups. At three weeks post-operatively, tumor growth at the injection, incision, and port sites was measured. Following standard midline incision, 50 percent of rats (26/50 rats) developed wound implantations, whereas only 25 percent of rats (14/57 rats) developed at least one trocar site wound implantation after laparoscopy with pneumoperitoneum. Fourteen percent of trocar sites (16/114 port sites) developed wound implantations. No tumor growth was noted on the peritoneal surfaces other than in the incisional sites. Laparoscopic-type procedure with pneumoperitoneum did not increase wound implantation in a syngeneic host/colon carcinoma rat model compared with the standard open incision technique.

The role of fibronectin in tumor implantation at surgical sites.

Fibronectins are a family of glycoproteins with modular functional domains. They mediate cell-cell and cell-matrix interactions which are important in embryogenesis, wound healing, metastasis and other processes. We present data on the influence of fibronectin on wound implantation of a murine mammary carcinoma line, TA3Ha. Fibronectin used in these studies was derived from bovine plasma, human serum, human foreskin fibroblasts, and mouse embryo cultures. TA3Ha cells rarely form tumors in the liver of syngeneic mice when injected intravenously but after hepatic wedge resection, 45% (107/240) of the mice develop tumors in the hepatic wound. Wound implantation is markedly reduced when the cells are pre-exposed to 200 micrograms/ml bovine plasma fibronectin (13%, P = 0.007), human serum fibronectin (0%, P = 0.02), human cellular fibronectin (0%, P = 0.02), or mouse cellular fibronectin (0%, P = 0.04). Lung colonization is also reduced by these fibronectins. These effects are not due to a cytotoxic action of fibronectin, since intraperitoneally injected fibronectin-treated cells form ascites tumor as effectively as do control untreated cells. Local application of a solution containing 0.25 mg/ml mouse cellular fibronectin to the hepatic wound reduces the frequency of tumor implantation from 45% to 5% (1/21, P = 0.001). No tumor implantation inhibition is seen when only suspending medium or albumin in suspending medium is used. The mechanism by which topical application of fibronectin reduces hepatic wound implantation of tumor cells is unclear, but this finding raises an exciting possibility of preventing local recurrence of cancer.

Inhibition of tumor implantation at sites of trauma by Arg-Gly-Asp containing proteins and peptides

We report on the inhibition of wound implantation by TA3Ha mammary carcinoma cells by Arg-Gly-Asp containing proteins and peptides using a hepatic wedge resection model. Intravenously injected TA3Ha cells rarely form tumor in the liver of syngeneic mice, but after hepatic wedge resection, 45% (107/240) of the mice develop tumors in the hepatic wound. Hepatic wound implantation is significantly (P = 0.01) inhibited by pretreating the cells with whole mouse plasma, but not with fibrinogen-depleted plasma or serum. Tumor inhibition is also achieved by pretreatment of cells with fibrinogen (P = 0.05-0.0004), fibronectin (P = 0.007) and laminin, but not by albumin. The active domain appears to be the RGDS sequence since the deca- and tetrapeptides containing RGDS inhibit wound implantation (P less than 0.05). However, the tetrapeptide Arg-Gly-Glu-Ser has no such activity. None of these agents affects ascites tumor formation by the intraperitoneally injected cells, suggesting that anchorage independent growth of cells is not affected. We propose that proteins and peptides containing RGD occupy the binding sites and prevent the cells from interacting with cell adhesion proteins in healing wounds. Proteins and/or peptides containing RGD may be useful for preventing local recurrence in postsurgical cancer patients.

I.Perineal Endometriosis

Endometriosis involving the perineum is rare. We have collected total 110 cases of perineal endometriosis from the literature which included only 5 cases in Japan. The cases reported have steadily increased in recent years. Based on the fact that four new cases have been found in our Hospital in a relatively shorter period, we postulate much higher incidence of this disease in Japan than that would appear from the literature. Almost all of cases were managed by episiotomy associated with parturition, and the resultant endometriosis developed in previous episiotomy scar or at its adjacent site. The patients commonly complained of painful paeineal swelling during menstruation. The period of latency between episiotomy and manifestation of symptoms varied 45 days to 14 years, showing a peak between 1 to 3 years. The average age of patients was reported to be between 28 and 38 years from different institutions, being somewhat lower than the usual age group for patients with endometriosis. The perineal lumps were recognized as a single dark reddish or bluish nodule which varied 1 to 2 cm in diameter. On palpation, the mass was less movable, often tender due to periodic bleeding into cystic space. It increased in size and became painful during menstrual period ; after menses, the nodule became almost painless and decreased in size. When the patients fulfilled these clinical features, the preoperative diagnosis of perineal endometriosis is possible. The treatment of choice is simple local excision. Complementary hormonal therapy has been suggested in several cases with large or recurrent mass. Definite histologic diagnosis can be made by demonstrating endometrial glands and stroma, accom-panying hemorrhage, and granulation tissues characteristically containing large amounts of hemosiderin and lipid debris. The specimens obtained from Gase 3 and 4 of our series were subjected to ultrastructural analysis.Electron microscopic examination showed that the epithelial cells in specimen of Case 3 retained the fine structure of endometrial cells during proliferative phase, and those in specimen of Case 4did that of the cells during early secretory phase. As to histogenesis of perineal endometriosis, the most cases reported including our cases can reasonably be explained by direct wound implantation of shed endometrial tissues during delivery. On the basis of this implantation theory, we proposed some measures to eliminate the occurrence of this disease.

EXPERIMENTAL USE OF CETRIMIDE IN THE PREVENTION OF WOUND IMPLANTATION WITH CANCER CELLS

EXPERIMENTAL USE OF CETRIMIDE IN THE PREVENTION OF WOUND IMPLANTATION WITH CANCER CELLS

WOUND IRRIGATION IN CANCER SURGERY

The incidence of local recurrence of cancer following radical mastectomy for breast carcinoma and radical surgery for head and neck malignancy is higher than is generally realized. In most instances the cause of the recurrence appears to be implantation, or more descriptively, wound seeding. This is the most insidious type of cancer dissemination with which the surgeon is confronted. Mechanical flushing of the wound with physiologic saline or distilled water is not sufficient to prevent the occurrence of implantation. The possibility of wound implantation can be decreased somewhat by careful surgical technique including the frequent changing of gloves and instruments. However, these methods alone do not appear to be sufficient to protect the patient from being seeded with his own tumor. In the experimental laboratory we determined that a 2% solution of a form of monoxychlorosene (Clorpactin XCB) and a 2 mg. % mechlorethamine (nitrogen mustard) solution, properly diluted so that

Wound Irrigation in Cancer Surgery

The incidence of local recurrence of cancer following radical mastectomy for breast carcinoma and radical surgery for head and neck malignancy is higher than is generally realized. In most instances the cause of the recurrence appears to be implantation, or more descriptively, wound seeding. This is the most insidious type of cancer dissemination with which the surgeon is confronted. Mechanical flushing of the wound with physiologic saline or distilled water is not sufficient to prevent the occurrence of implantation. The possibility of wound implantation can be decreased somewhat by careful surgical technique including the frequent changing of gloves and instruments. However, these methods alone do not appear to be sufficient to protect the patient from being seeded with his own tumor. In the experimental laboratory we determined that a 2% solution of a form of monoxychlorosene (Clorpactin XCB) and a 2 mg. % mechlorethamine (nitrogen mustard) solution, properly diluted so that