Transvaginal repair of a large chronic porcine ventral hernia with synthetic mesh using NOTES

Transvaginal placement of synthetic mesh to repair large porcine hernia using NOTES technology appears to be a feasible alternative to traditional techniques.

Background:

Ventral incisional hernias still remain a common surgical problem. We tested the feasibility of transvaginal placement of a large synthetic mesh to repair a porcine hernia.

Methods:

Seven pigs were used in this survival model. Each animal had creation of a 5-cm hernia defect and underwent a transvaginal repair of the defect with synthetic mesh. A single colpotomy was made using a 12-cm trocar for an overtube. The mesh was cut to size and placed through the trocar. A single-channel gastroscope with an endoscopic atraumatic grasper was used for grasping sutures. Further fascial sutures were placed every 5cm.

Results:

Mesh repair was feasible in all 7 animals. Mean operative time was 133 minutes. Technical difficulties were encountered. No gross contamination was seen at the time of necropsy. However, 5 animals had positive mesh cultures; 7 had positive cultures in the rectouterine space in enrichment broth or on direct culture.

Conclusion:

Transvaginal placement of synthetic mesh to repair a large porcine hernia using NOTES is challenging but feasible. Future studies need to be conducted to develop better techniques and determine the significance of mesh contamination.

Transgastric biologic mesh delivery and abdominal wall hernia repair in a porcine model

BACKGROUND AND STUDY AIMS

Incisional abdominal wall hernias currently require repair with open or laparoscopic surgery, which is associated with wound complications and recurrent hernia formation. Natural orifice transluminal endoscopic surgery (NOTES) techniques may have the potential to decrease the morbidity associated with hernia repair. The aim of this study was to repair a chronic ventral hernia with a biologic mesh placed transgastrically in a porcine model.

MATERIALS AND METHODS

Six pigs underwent creation of an incisional abdominal wall hernia. At least 4 weeks later, transgastric repair was done using an underlay biologic mesh with at least 5 cm of overlap from the hernia fascial edge. The mesh was secured with transfascial sutures and the stomach was closed with a sutured gastropexy. Pigs were evaluated 2 weeks later by laparoscopy. Pigs were sacrificed and necropsy wa s performed 4 weeks after the repair.

RESULTS

Six pigs underwent hernia repair lasting a mean (+/- SD) of 204 +/- 123 minutes, with one perioperative death. At 2 weeks after hernia repair, laparoscopy showed significant adhesions in all pigs; one pig had extensive mesh infection and was sacrificed. Necropsy on one pig at 2 weeks and four pigs at 4 weeks showed complete coverage of the hernia defect in all pigs. All pigs had mesh abscesses or a positive mesh culture.

CONCLUSION

Transgastric repair of a chronic ventral hernia is technically feasible. Difficulties with mesh delivery and infection need to be overcome before this approach can be used in humans.

In search of the best peritoneal adhesion model: comparison of different techniques in a rat model

BACKGROUND

Adhesion-related complications after abdominal surgery result in significant morbidity and costs. Results from animal studies investigating prevention or treatment of adhesions are limited due to lack of consistency in existing animal models. The aim of this study was to compare quality and quantity of adhesions in four different models and to find the best model.

MATERIALS AND METHODS

This study was approved by the University of Missouri Animal Care and Use Committee (ACUC). Forty female rats were randomly assigned to four different groups of 10 animals each. Adhesion created was performed utilizing the four techniques: Group 1 - parietal peritoneum excision (PPE), Group 2 - parietal peritoneum abrasion (PPA), Group 3 - peritoneal button creation (PBC), and Group 4 - cecal abrasion (CA). Rats were allowed to recover and necropsy was performed on postoperative d 14. Adhesions were scored by an established quantitative and qualitative scoring systems. The midline incision served as the control in each animal.

RESULTS

The four groups were not equal with respect to both quantity score (P<0.001) and quality score (P=0.042). The PBC group had the highest quantity of adhesions. The highest quality of adhesion was seen in the PPE group. A multivariate analysis carried out to quantify the performance of each model clearly demonstrated that PBC exhibited the best results in terms of both quantity and quality.

CONCLUSIONS

The button technique (PBC) is most consistent and reproducible technique for an intra-abdominal adhesion model. This model can help in the study and development of substances to prevent adhesion formation in the future.

Is Endocrine Therapy Really Pleasant? Considerations about the Long-Term Use of Antihormonal Therapy and Its Benefit/Side Effect Ratio

Endocrine therapy has become a key part in the adjuvant treatment of hormone responsive breast cancer. The positive effect on relapse risk reduction is well defined, but therapy is not free from bothersome side effects for which estrogen deprivation accounts to a great extent. Since endocrine therapy is usually prescribed for 5 years or longer to optimally display its protective effect, and because physical strain is missing, good tolerability and safety properties are important, particularly in low-risk patients. While tamoxifen has been the standard adjuvant endocrine treatment with well documented efficiency, it is increasingly replaced by third generation aromatase inhibitors due to their better effectiveness and tolerability. Because tamoxifen holds a risk for life-threatening adverse events such as endometrial cancer, pulmonary embolism, and stroke, its recommended duration of therapy is limited to 5 years, also because extension beyond that time did not produce a measurable advantage. While some side effects are present both with tamoxifen and aromatase inhibitors, differences in side effect profiles are well established. Although side effects of aromatase inhibitor-related therapy usually are mild and common to symptoms of menopause, misconception of the symptoms and their mechanism of action, as well as lack of knowledge about how to handle them, can easily lead to dangerous discontinuation of therapy.

Laparoscopic appendectomy--is it worth the cost? Trend analysis in the US from 2000 to 2005

BACKGROUND

Although laparoscopic appendectomy is widely used for treatment of appendicitis, it is still unclear if it is superior to the open approach.

STUDY DESIGN

From the Nationwide Inpatient Sample 2000 to 2005, hospitalizations with the primary ICD-9 procedure code of laparoscopic (LA) and open appendectomy (OA) were included in this study. Outcomes of length of stay, costs, and complications were assessed by stratified analysis for uncomplicated and complicated appendicitis (perforation or abscess). Regression methods were used to adjust for covariates and to detect trends. Costs were rescaled using the hospital and related services portion of the Medical Consumer Price Index.

RESULTS

Between 2000 and 2005, 132,663 (56.3%) patients underwent OA and 102,810 (43.7%) had LA. Frequency of LA increased from 32.2% to 58.0% (p < 0.001); conversion rates decreased from 9.9% to 6.9% (p < 0.001). Covariate adjusted length of stay for LA was approximately 15% shorter than for OA in both uncomplicated and complicated cases (p < 0.001). Adjusted costs for LA were 22% higher in uncomplicated appendicitis and 9% higher in patients with complicated appendicitis (p < 0.001). Costs and length of stay decreased over time in OA and LA. The risk for a complication was higher in the LA group (p < 0.05, odds ratio=1.07, 95% CI 1.00 to 1.14) with uncomplicated appendicitis.

CONCLUSIONS

LA results in higher costs and increased morbidity for patients with uncomplicated appendicitis. Nevertheless, LA is increasingly used. Patients undergoing LA benefit from a slightly shorter hospital stay. In general, open appendectomy may be the preferred approach for patients with acute appendicitis, with indication for LA in selected subgroups of patients.

Transgastric cholecystectomy using a prototype endoscope with 2 deflecting working channels (with video)

BACKGROUND

Transgastric cholecystectomy has been shown to be feasible in animal models and human case reports but cumbersome with current available instrumentation.

OBJECTIVE

To evaluate a prototype endoscope with 2 working channels with deflectors at the distal tip for performance of transgastric cholecystectomy.

DESIGN

Animal study, nonsurvival and survival.

ANIMALS

Sixteen male pigs.

SETTING

University hospital.

INTERVENTION

Transgastric cholecystectomy in 6 nonsurvival pigs by using several different dual-channel endoscopes and 10 survival pigs by using the Olympus dual-channel endoscope with an up-down deflecting channel to the left of the objective lens and a left-right deflecting channel located below the lens. Gallbladder fundic retraction was performed with the aid of one laparoscopic grasper.

RESULTS

Cholecystectomy was successful in all survival animals. Median procedure time was 81 minutes (range 31-163 minutes), with a decrease over time. Visualization of all structures was achieved, and clipping of the cystic duct and artery was successful in all cases. Dissection of the gallbladder via the left-right channel was enhanced with retraction via the up-down deflecting channel. Nine of 10 animals survived without complications. One animal died, on postoperative day 2, secondary to peritonitis due to a leak from the gastrotomy site.

CONCLUSIONS

This endoscope, with deflecting working channels, allows transgastric cholecystectomy in pigs. The endoscope was stable enough to be used without an overtube and facilitated retraction and dissection. This endoscope is promising for use in transgastric cholecystectomy in human beings.

Colonic sterilization for natural orifice translumenal endoscopic surgery (NOTES) procedures: a comparison of two decontamination protocols

BACKGROUND

This study aimed to evaluate the effect of two different sterilization protocols on the bacterial counts in the swine colon as preparation for natural orifice translumenal endoscopic surgery (NOTES) surgery.

METHODS

In this study, 16 swine were randomized to two different colonic sterilization protocols: low colonic irrigation using 300 ml of a 1:1 dilution of 10% povidone-iodine (Betadine) with sterile saline, followed by 1 g of cefoxitin dissolved in 300 ml of saline or two consecutive 300-ml irrigations using a quaternary ammonium antimicrobial agent (Onamer M). Colonic cultures were taken before colonic cleansing after a decontamination protocol and after completion of the NOTES procedure. The Invitrogen live/dead bacterial viability kit was used to assess for change in the bacterial load. A qualitative culture of peritoneal fluid was obtained at the end of the NOTES procedure. Colon mucosal biopsies obtained immediately after the sterilization procedure and at the 2-week necropsy point were evaluated for mucosal changes.

RESULTS

Protocol 1 resulted in an average 93% decrease in live colonic bacteria versus 90% with protocol 2 (nonsignificant difference). After a NOTES procedure, group 1 had a 62% increase in live bacteria and group 2 had a 31% increase (nonsignificant difference). Peritoneal cultures also were obtained. Bacteria were isolated from the peritoneal fluid of all the animals, and two or more species were isolated from 75% of the animals. There was no evidence of peritoneal infection at necropsy. Reactive epithelial changes and mild inflammation were the only pathologic abnormalities. No changes were noted at histologic evaluation of colonic mucosa after 2 weeks, demonstrating that these were temporary changes.

CONCLUSION

Colonic irrigation with Betadine and antibiotics are as effective for bacterial decontamination of the swine colon as a quaternary ammonium compound. The results of this study support the use of either protocol. Despite thorough decontamination, peritoneal contamination occurs. The significance of this for humans is unknown.

Gastrotomy creation and closure for NOTES using a gastropexy technique (with video)

BACKGROUND

Safe and efficient gastrotomy creation and closure is pivotal for natural orifice transluminal endoscopic surgery (NOTES).

OBJECTIVE

To test a method of transgastric access and closure with commercially available devices.

DESIGN

An animal survival study.

SETTING

University hospital.

PATIENTS

Fifteen pigs.

INTERVENTIONS

By using a surgical suture passer, under endoscopic guidance, 3 percutaneous stay sutures were placed, in a triangular fashion, through the gastric wall. A gastrotomy was created with a dilation balloon, which was introduced over a guidewire through the gastric wall in the center of the 3 sutures. After performing a NOTES procedure, the gastrotomy was closed by tying the sutures. Necropsies were performed after 2 to 4 weeks.

MAIN OUTCOME MEASUREMENTS

Success and time of gastrotomy creation and closure, and intraoperative and postoperative complications.

RESULTS

Gastrotomies were successfully created and closed in all the animals. The median time to create a gastrotomy was 19 minutes (range 11-85 minutes), and the median closure time was 1 minute (range 1-45 minutes). One pig died on postoperative day 1 because of peritonitis caused by a leaking gastrotomy site that extended beyond the stay sutures. There were no other gastrotomy-related complications. All gastrotomies were well healed at the necropsy.

LIMITATION

No control group.

CONCLUSIONS

We evaluated a simple method by using the principles of the PEG technique combined with a gastropexy, which is familiar to the majority of endoscopists. Strict attention to the gastrotomy site is needed, because one leak was from the gastrotomy site that extended beyond the stay sutures.

Endoscopic colotomy closure for natural orifice transluminal endoscopic surgery using a T-fastener prototype in comparison to conventional laparoscopic suture closure

BACKGROUND

Safe and efficient endoscopic closure of a colotomy is essential for transcolonic peritoneal access or endoscopic full-thickness resection of the colon, if open or laparoscopic surgery is to be avoided.

OBJECTIVE

To compare the feasibility and safety of colotomy closure with the newly developed Tissue Approximation System (TAS, Ethicon Endo-Surgery, Inc.) to conventional laparoscopic suture closure.

DESIGN

Prospective randomized survival animal study involving 16 pigs.

SETTING

University hospital.

INTERVENTIONS

Pigs were randomized for closure of a 2- to 3-cm full-thickness colotomy with the TAS or with a conventional laparoscopic running suture.

MAIN OUTCOME MEASUREMENTS

Success of colotomy closure, time of colotomy closure, postoperative infection, and complication rates.

RESULTS

Colotomies were successfully closed in all animals. Median closure time (range) was 39.5 minutes (25-95 min) in the TAS group and 23 minutes (16-40 min) in the laparoscopic group (P = .0134). There were no postoperative infections or complications.

LIMITATIONS

Closure with the TAS was performed under laparoscopic vision. There was no control group without closure of the colotomy site.

CONCLUSIONS

Colotomies are safely closed with the TAS with comparable results to laparoscopic closure. The TAS may serve as a useful tool to close full-thickness colon defects or colotomy sites made for transluminal endoscopic procedures.

Stent placement for benign colonic stenosis: case report, review of the literature, and animal pilot data

BACKGROUND

Permanent metal stent placement for malignant intestinal obstruction has been proven to be efficient. Temporary stents for benign conditions of the colon and rectum are less studied. This is a case study, review of the literature, and observation from an animal model on placement of stents in the colorectum for benign disease.

MATERIALS AND METHODS

A 55-year-old man presented with recurrent obstructions from a benign stricture of the distal sigmoid colon. After failed balloon dilations, a polyester coated stent was placed. The purpose of the stent was to improve symptoms and avoid surgery. The stent was expelled after 5 days. We conducted a literature review of stents placed for benign colorectal strictures and an animal study to evaluate stent migration.

RESULTS

In the literature, there were 53 reports of uncovered metal stents, four covered metal stents, and six polyester stents. Patency rates were 71%, and migration rate was 43%. Migration occurred earlier with polyester stents (mean=8 days) versus covered (32 days) or uncovered metal stents (112 days). Severe complications were seen in 23% of patients. Four 45-kg pigs underwent rectosigmoid transection with a 21-mm anastomosis and endoscopic placement of a Polyflex stent. Two stents were secured with suture. Stents without fixation were expelled within 24 h of surgery. Stents with fixation were expelled between postoperative days 2 and 14.

CONCLUSION

Stents for the treatment of benign colorectal strictures are safe, with comparable patency rates between stent types. Metal stents can cause severe complications. In a pig model, covered polyester stents tend to migrate early even with fixation. Further investigation needs to focus on new stent designs and/or better fixation.

Evaluation of a novel endoluminal stapling procedure to restrict the lower esophageal sphincter and reduce reflux

BACKGROUND AND STUDY AIMS

An effective, safe, and long-lasting endoluminal treatment for gastroesophageal reflux disease (GERD) would be an attractive prospect. We developed an endoluminal technique to restrict and tighten the lower esophageal sphincter (LES), by using a transoral endoscopic stapling device in a porcine model.

PATIENTS AND METHODS

Pre-interventional evaluation comprised endoscopy, manometry, and 48-hour pH measurement of the distal esophagus using the catheterless BRAVO pH capsule. By placing the endoluminal stapling device at the LES and firing a 2.5-cm staple line, a vertical plication was created. In five pilot pigs (phase 1), plications were placed in various locations at the LES. In another five pigs (phase 2), plications were placed uniformly at the mid level of the LES on the lesser curvature side. Measurements were repeated 2 weeks after the procedure. Necropsy and histological analysis were performed.

RESULTS

Endoluminal stapling was successfully completed in all animals. In phase 2, the median procedure time was 15 minutes (range 10-55 minutes). LES pressure increased from 10.5 mmHg (+/- 2.5 mmHg) to 14.3 mmHg (+/- 3.8 mmHg) (P = 0.038). Median percentage of time with pH below 4 decreased from 6.6% (range 2.9%-48.8%) to 2.2% (range 0%-10.4%) (P = 0.043). Histology showed the staple line involving the muscular layer in all pigs. A gap was present in the central part of the staple line in three pigs resulting in a mucosa-muscular bridge of tissue. This bridge did not influence the results.

CONCLUSION

This novel endoluminal technique is feasible and safe in a porcine model over 2 weeks. It is appealing due to its simplicity and ease of application. Further studies aimed at eliminating the gap in the staple line and investigating more animals over longer survival periods are needed.

Placement of a covered polyester stent prevents complications from a colorectal anastomotic leak and supports healing: randomized controlled trial in a large animal model

BACKGROUND

Anastomotic leaks after colorectal operation continue to be a significant cause of morbidity. A covered endoluminal stent could seal a leak and eliminate the need for diversion. The aim of this study was to test the efficacy of a temporary covered stent to prevent leak related complications.

METHODS

Sixteen adult pigs (80-120 lbs) underwent open transection of the rectosigmoid followed by anastomosis with a circular stapler. Eight animals (study group) underwent endoscopic placement of a 21-mm covered polyester stent. Eight control group animals were left without stents. In all animals, a 2-cm leak was created along the anterior portion of the anastomosis. The animals were killed after 2 weeks and evaluated for abdominal infection, fistulae, and adhesions. The anastomosis was excised and the following parameters were assessed by a pathologist blinded to treatment: mucosal interruption (mm), inflammatory response, collagen type I and III, granulation, and fibrosis (grade 0-4).

RESULTS

Stents were spontaneously expelled between postoperative days 6 and 9. At necropsy, none of the animals in the study group had leak related complications, whereas in the control group, 5 (63%) developed intraabdominal infection (4 abscesses, 1 fistula) at the anastomosis (P = .002). Dense adhesions to the anastomosis were found in 7 (88%) control animals. On histology, anastomotic sites in the study group had significantly less mucosal interruption and granulation. Two pigs in the study group died on postoperative day 7, one due to evisceration and one from bladder necrosis. The mortality result is not different from controls (P = .47), both events seem to be unrelated to stent placement.

CONCLUSION

Temporary placement of a covered polyester stent across a colorectal anastomosis prevents leak-related complications and supports the healing of anastomotic leaks.

Endoscopic colotomy closure after full thickness excision: comparison of T fastener with multiclip applier

BACKGROUND AND STUDY AIMS

Safe, reliable, and efficient endoscopic closure of a colotomy is paramount for endoscopic full thickness excision of the colon. Two newly developed devices, the Tissue Apposition System (TAS) and the InScope Multi-Clip Applier (IMCA), may help to achieve this. The aim of this study was to determine the feasibility of using each device to close colotomies after full thickness wall excisions.

MATERIAL AND METHODS

12 pigs were used in the study. After laparoscopic full thickness excision of the colonic wall, the defect was closed using either the TAS or the IMCA. Closure was performed under laparoscopic vision. Success of colotomy closure, time taken for colotomy closure, postoperative infections, and complication rates were recorded.

RESULTS

Complete closure was achieved in 6/6 pigs in the TAS group. In 5/6 pigs in the IMCA group closure was successful; in one pig laparoscopic assistance was used. Median closure time (range) was significantly lower in the TAS group at 48 minutes (15 - 51) vs. 76 minutes (43 - 145) in the IMCA group. There were no postoperative infections or complications.

CONCLUSIONS

Endoscopic closure after full thickness colonic wall excision is feasible with both the TAS and the IMCA. Closure times are significantly shorter and handling is easier with the TAS. Combined use of both systems might be beneficial.

Do we need HER-2/neu testing for all patients with primary breast carcinoma?

BACKGROUND

HER-2/neu is a valuable prognostic marker in primary breast carcinoma. Controversy surrounds the correlation between HER-2/neu expression and other prognostic markers, as has been discussed in preclinical and clinical studies. The objective of the current study was to investigate the probability, calculated using parameters that are assessed routinely in clinical practice, that patients with breast carcinoma had positive HER-2/neu status.

METHODS

The authors evaluated HER-2/neu status in 923 consecutive patients with breast carcinoma by immunohistochemical methods. Correlations involving HER-2/neu status, estrogen receptor (ER) and progesterone receptor (PR) status, tumor grade, patient age, lymph node involvement, and tumor size were evaluated using the Mantel-Haenszel chi-square test and the Spearman correlation. The authors created a simple scoring system (i.e., the diagnostic instrument for validation of HER-2/neu score) to define subgroups of patients with breast carcinoma and to determine the likelihood of HER-2/neu positivity.

RESULTS

HER-2/neu overexpression was correlated significantly with negative ER (P = 0.0001) and PR status (P = 0.0001), Grade 3 (G3) lesions (P = 0.0001), and young age (P = 0.006). The likelihood of HER-2/neu positivity in a patient with positive ER and PR status and G1/G2 disease was approximately 6.1%.

CONCLUSIONS

The authors demonstrated in a large patient series that HER-2/neu overexpression was associated with negative hormone receptor status, G3, and young age. In a subgroup of patients presenting with hormone-responsive and G1/G2 tumors, the likelihood of HER-2/neu overexpression was very small. Therefore, the assessment of HER-2/neu status in this subgroup of patients with breast carcinoma may be considered unnecessary, unless the role of HER-2/neu status in adjuvant treatment has been proven.

Influence of Neoadjuvant Therapy with Epirubicin and Docetaxel on the Expression of HER2/neu in Patients with Breast Cancer

BACKGROUND

In primary breast cancer, the expression levels of biological markers relevant to the progression of the disease may be altered by administration of anticancer drugs. Since neoadjuvant chemotherapy with epirubicin and docetaxel is increasingly used in advanced breast cancer, our purpose was to assess the influence of this neoadjuvant chemotherapy on the expression of the growth factor receptor HER2/neu.

PATIENTS AND METHODS

We investigated changes of HER2/neu status by immunohistochemistry (IHC) and applied additional fluorescence in situ hybridization (FISH) in patients with potential modulation of HER2/neu status after administration of neoadjuvant chemotherapy with docetaxel and epirubicin in 97 breast cancer patients. The influence of neoadjuvant chemotherapy on HER2/neu expression was calculated by correlation of HER2/neu status before and after chemotherapy.

RESULTS

The accuracy of HER2/neu assessment before and after neoadjuvant chemotherapy by IHC combined with FISH analysis in selected cases was 100%. The evaluation of HER2/neu status in these patients by IHC alone yielded accuracy of 93%. Neoadjuvant chemotherapy with epirubicin and docetaxel caused no significant modulation of HER2/neu status (p = 0.66).

DISCUSSION

The administration of epirubicin and docetaxel in the neoadjuvant setting is not associated with significant changes of HER2/neu status in primary breast cancer. As a consequence, drug resistance or sensitivity is not induced by modulation of HER2/neu expression. Moreover, the time of assessment of the HER2/neu status is not a critical factor under neoadjuvant therapy with epirubicin and docetaxel.

Development of 'no-reflow' phenomenon in ischemia/reperfusion injury: failure of active vasomotility and not simply passive vasoconstriction

BACKGROUND/AIM

Local blood flow failure (no-reflow phenomenon) during ischemia/reperfusion (I/R) injury may be mediated by interstitial edema formation (passive vasoconstriction) and/or microvascular spasm (active vasoconstriction). The development of the no-reflow phenomenon in the rabbit hind limb I/R model and the influence of treatment with L-arginine and/or antioxidative vitamins were investigated.

METHODS

Untreated rabbits were compared with those treated with L-arginine (4 mg/kg/min) or antioxidative vitamins (0.4 ml/kg) alone or in combination during hind limb I/R (2.5/2 h). Interstitial edema formation and microvessel diameter alterations were measured morphometrically. Capillary blood perfusion was measured continuously with laser Doppler flowmetry.

RESULTS

I/R injury was expressed by interstitial edema formation (interstitial space increase by 80%), microvascular constriction (microvessel cross-sectional area decrease by 30%), and development of no-reflow phenomenon (blood flow reduction by 60%). Treatment with antioxidative vitamins alone or L-arginine alone reduced interstitial edema by 22 and 31%, consequently, while combined L-arginine/antioxidative vitamin treatment showed a more pronounced edema reduction by 40%. Treatment with only antioxidative vitamins failed to influence the development of no-reflow, although interstitial edema formation was reduced. L-Arginine treatment alone or in combination with antioxidative vitamins prevented microvascular constriction and preserved blood flow after reperfusion without development of no-reflow despite still apparent interstitial edema.

CONCLUSIONS

Affections of active vasomotility and not merely passive changes of external pressure (i.e., interstitial edema formation) should be considered important in the development of microvascular constriction during 'no-reflow' phenomenon.

Collagen- versus gelatine-coated Dacron versus stretch PTFE bifurcation grafts for aortoiliac occlusive disease: long-term results of a prospective, randomized multicenter trial

BACKGROUND

In this prospective randomized multicenter trial, knitted gelatine-coated Dacron, knitted collagen-coated Dacron, and stretch polytetrafluoroethylene (PTFE) aortic bifurcation grafts were compared for their long-term results.

METHODS

Between 1991 and 1998, 149 patients undergoing elective revascularization for aortoiliac occlusive disease were prospectively randomized at 3 tertiary referral centers of vascular surgery. The patients received either gelatine-coated Dacron (GEL-D) grafts (n = 52), collagen-coated Dacron (COL-D) grafts (n = 49), or stretch PTFE grafts (n = 48).

RESULTS

No intraoperative deaths were recorded. The 30-day mortality was 4%. The mean follow-up time was 97 months. Primary patency rates were 77% for GEL-D, 78% for COL-D, and 79% for PTFE at 8 years. The differences were not different (P >.8). Secondary corrected 8-year patency rates were also not significantly different (P >.5): 91% for GEL-D, 96% for COL-Dm and 90% for PTFE. Five Dacron and 1 PTFE grafts were affected by infections.

CONCLUSIONS

Bifurcation grafts for revascularization of aortoiliac occlusive disease using these 3 materials were comparable in terms of primary and secondary patency and long-term complication rates.

Pattern of hormone receptor status of secondary contralateral breast cancers in patients receiving adjuvant tamoxifen

In breast cancer patients receiving adjuvant tamoxifen after unilateral treatment, contralateral breast cancer (CBC) is extremely rare. As a result, only limited data are available on the hormone receptor status of CBCs evolving in tamoxifen-treated patients. The aim of our investigation was to evaluate the pattern of hormone receptor status of CBCs in patients treated with adjuvant tamoxifen at our institution. Material was collected from 35 patients. We have found that 27 of the 35 patients included into our investigation developed an estrogen receptor (ER)-positive CBC despite adjuvant tamoxifen. Seven ER-positive CBCs occurred after tamoxifen had been discontinued, and 20 patients developed an ER-positive CBC while receiving tamoxifen. Notably, 80% of these CBCs displayed moderate-to-strong levels of ER. In our opinion, the selection of ER-negative CBCs, which has previously been implicated to be the pivotal mechanism of tumor escape of CBCs evolving in tamoxifen-treated patients, is only one mechanism of tumor escape in patients receiving antiestrogen treatment. The emergence of ER-positive CBCs in the majority of tamoxifen-treated patients suggests that alternative escape mechanisms may be equally relevant. These include the emergence of ER-positive CBCs that display tamoxifen-dependent growth properties, the selection of CBCs that are tamoxifen resistant because of ER mutations with altered ER function, and, finally, the selection of ER-positive CBCs that overexpress c-erbB2.

General compliance after liver transplantation for alcoholic cirrhosis

In recent years, alcoholic cirrhosis has been accepted as an indication for OLT, compliance of patients suffering from alcoholic cirrhosis is still under discussion, however. 118 patients who had undergone OLT for alcoholic cirrhosis were considered for analysis. The mean follow-up time of the study population was 53.7 +/- 38.9 months. Compliance was defined by 3 parameters: 1. Sobriety. Fifteen (13%) out of 118 recipients suffered an alcohol relapse during the observation period. There was no difference between the groups with or without alcohol relapse concerning compliance with medication, incidence of rejection, or adherence to check-ups. 2. Drug-compliance. Nineteen recipients (16 %) were not within the target range with the immunosuppressive medication. Comparison of the compliant- and non-compliant groups produced a significant difference for late acute rejection, the other parameters being similar in the subgroups. 3. Adherence to appointments. Nearly all patients in the study population ( > 95 %) were compliant with both transplant and psychological appointments in the outpatient clinic. In conclusion, analysis of our data indicates that patients with OLT for alcoholic cirrhosis are compliant, although alcohol relapse occurs in 13 % of recipients.