Diagnostic performance of a novel device for real-time margin assessment in lumpectomy specimens.

BACKGROUND: Margin status in breast lumpectomy procedures is a prognostic factor for local recurrence and the need to obtain clear margins is often a cause for repeated surgical procedures. A recently developed device for real-time intraoperative margin assessment (MarginProbe; Dune Medical Devices, Caesarea, Israel), was clinically tested. The work presented here looks at the diagnostic performance of the device. METHODS: The device was applied to freshly excised lumpectomy and mastectomy specimens at specific tissue measurement sites. These measurement sites were accurately marked, cut out, and sent for histopathologic analysis. Device readings (positive or negative) were compared with histology findings (namely malignant, containing any microscopically detected tumor, or nonmalignant) on a per measurement site basis. The sensitivity and specificity of the device was computed for the full dataset and for additional relevant subgroups. RESULTS: A total of 869 tissue measurement sites were obtained from 76 patients, 753 were analyzed, of which 165 were cancerous and 588 were nonmalignant. Device performance on relatively homogeneous sites was: sensitivity 1.00 (95% CI: 0.85-1), specificity 0.87 (95% CI: 0.83-0.90). Performance for the full dataset was: sensitivity 0.70 (95% CI: 0.63-0.77), specificity 0.70 (95% CI: 0.67-0.74). Device sensitivity was estimated to change from 56% to 97% as the cancer feature size increased from 0.7 mm to 6.6 mm. Detection rate of samples containing pure DCIS clusters was not different from rates of samples containing IDC. CONCLUSIONS: The device has high sensitivity and specificity in distinguishing between normal and cancer tissue even down to small cancer features.

Endoluminal compression clip: full-thickness resection of the mesenteric bowel wall in a porcine model.

BACKGROUND: Performing a full-thickness intestinal wall resection of a sessile polyp located on the mesenteric side with a compression clip may lead to compression of mesenteric vessels. The application of such a clip may therefore cause a compromised blood supply in the particular bowel segment, leading to perforation. OBJECTIVE: To evaluate the performance of a newly developed, nitinol compression clip, called the NiTi clamp, for full-thickness resection of the bowel wall, while the clip is deliberately deployed endoluminally on the mesenteric side. DESIGN: Prospective animal study. Multinational, multidisciplinary; gastroenterology and general surgery, research cooperation. SETTING: Animal research laboratory. INTERVENTION: Six pigs were operated upon and endoscopically evaluated and then killed after 3 weeks. Linear compression closure clips based on nitinol springs were used. Three longitudinal enterotomies were performed: in the cecum, spiral colon, and proximal rectum. Four clips were deployed in each animal. MAIN OUTCOME MEASUREMENTS: A total of 23 clips were deployed. The average expulsion day was 9 days. RESULTS: All but 3 clips were normally expelled. One pig developed bowel ischemia due to intussusception. In endoscopic procedures, no signs of significant segmental mucosal ischemia were found. The macroscopic appearance of the compression closure lines was thin and delicate, but epithelialization was significantly delayed at 5 sites. LIMITATION: Differences between porcine and human colorectal anatomy. CONCLUSION: Full-thickness clamping of the bowel with the NiTi clamp, including the local mesenteric vasculature, does not significantly impair local healing of the clamp site and gives hope to further development of novel full-thickness endoscopic resection technologies.

A prospective, randomized, controlled, multicenter study of a real-time, intraoperative probe for positive margin detection in breast-conserving surgery.

BACKGROUND: This randomized, double-arm trial was designed to study the benefit of a novel device (MarginProbe, Dune Medical Devices, Caesarea, Israel) in intraoperative margin assessment for breast-conserving surgery (BCS) and the associated reduction in reoperations. METHODS: In the device group, the probe was applied to the lumpectomy specimen and additional tissue was excised according to device readings. Study arms were compared by reoperation rates and by correct surgical reaction confirmed by histology. RESULTS: Three hundred patients were enrolled. Device use was associated with improved correct surgical reaction, defined as additional re-excision in all histologically detected positive margins, with tumor within 1 mm of inked margin. The repeat lumpectomy rate was significantly reduced by 56% in the device arm: 5.6% versus 12.7% in the control arm. There were no differences in excised tissue volume or cosmetic outcome. CONCLUSIONS: Intraoperative use of the MarginProbe for positive margin detection is safe and effective in BCS and decreases the rate of repeat operations.

Simulation of a colorectal polypoid lesion--a pilot porcine model.

BACKGROUND: Large sessile polyps almost always contain villous tissue with appreciable premalignant potential and tend to recur locally after colonoscopic resection. Developing new endoscopic techniques for the removal of polyps requires a large animal model of colorectal polypoid lesions. So far, no appropriate large animal model of a colorectal or other GI polyp has been described in the English literature. OBJECTIVE: Our purpose was to develop a large animal model simulating large, perfused and viable, sessile colorectal polypoid lesions, with distinct easily detectable histologic features. SETTING: An animal laboratory. INTERVENTIONS: Two simulated rectal polyps, using 2 different techniques, were created in each of 10 animals. The polyps were simulated by ovarian tissue that was introduced either intraluminally through the rectal wall or into a dissected submucosal space in the rectal wall. In 2 animals the created polyps were endoscopically resected. RESULTS: All submucosal lesions were sessile-like polypoid lesions because the base of the polyp was the widest diameter of the lesion. All transmural polypoid lesions had short and thick pedicles. Resection by snaring and cutting was demonstrated to be feasible. MAIN OUTCOME MEASUREMENTS: The mean measurements of the submucosal-simulated polyps were as follow: 1.74 cm (+/-0.32) x 2.07 cm (+/-0.42) x 1.51 cm (+/-0.27). The mean measurements of the transmural-simulated polyps were significantly larger: 2.55 cm (+/-0.52) x 3.57 cm (+/-1.1) x 2.7 cm (+/-0.64). LIMITATION: This model does not simulate a real intestinal neoplasia. CONCLUSION: Either method, the submucosal or the transmural, could be helpful in the research and development efforts of surgical and endoscopic treatments of intestinal polyps.

Compression gastrointestinal anastomosis.

The creation of anastomoses between various parts of the GI tract is a major task in the daily practice of oncological, reconstructive and transplant surgery. The most widely used anastomosing techniques today involve the use of sutures or metal titanium staples. Both techniques involve foreign material penetrating the tissue and evoking localized inflammatory response, tissue injury and breaking of mucosal barriers that may facilitate bacterial growth within the anastomotic line, increasing the propensity to anastomotic-related morbidity. Different types of compression devices were successfully used clinically in the past. The history and evolving characteristics of this technology is reviewed. Nitinol-based solutions for the creation of compression anastomosis are evaluated as a possible potential for revolutionary impact on the current surgical methods and anastomosing technology in the alimentary tract and beyond.

A device for real-time, intraoperative margin assessment in breast-conservation surgery.

BACKGROUND: This trial was designed to study performance of a novel handheld probe (Dune Medical Devices, Caesarea, Israel) in intraoperative detection of positive margins and its potential benefit toward minimizing the positive margin rate. METHODS: The probe was intraoperatively applied to 57 lumpectomy specimens. Surgeons were blinded to device output, and surgical decisions were not affected by probe data. Probe readings were compared with histological analysis per margin and per patient. RESULTS: Nineteen of 22 (86%) pathology-positive patients were intraoperatively detected with device use. Per-margin sensitivity was .71, and specificity was .68, maintained within a range of positive margin definitions (0-.4 cm). CONCLUSIONS: The device is an effective tool for intraoperative detection of positive margins with the potential for significant positive margin rate reduction.

End-to-end compression anastomosis of the rectum: a pig model.

BACKGROUND: Generations of investigators have attempted to achieve compression bowel anastomosis by a sutureless device, providing temporary support to the tissue and facilitating the natural healing process. The biocompatibility of nickel-titanium alloy has made it attractive for use in medical implants and devices, and several studies have described the creation of a side-to-side compression anastomosis in colon surgery with a nickel-titanium clip. We evaluated the feasibility and safety of a newly designed gun for applying a nickel-titanium compression anastomosis ring (CAR) to create an end-to-end colorectal anastomosis in a porcine model. MATERIALS AND METHODS: A segment of the proximal rectum was resected in 25 pigs. The bowel ends were anastomosed transanally by an end-to-end CAR device. The animals' follow-up continued for up to 8 weeks, and included general health status, weight gain, blood tests, and abdominal X-ray. They were then sacrificed. The anastomoses were studied for burst pressure, anastomotic index, and histopathology. RESULTS: One pig died due to iatrogenic bowel injury unrelated to the CAR device. There was no other morbidity/mortality. The other animals recovered and gained weight. Burst pressure studies demonstrated a minimum pressure of 160 mmHg at time point 0 that escalated quickly to >300 mmHg. The mean anastomotic index after 8 weeks was 0.81. Histologic evaluation revealed minimal inflammation and minimal fibrosis at the anastomosis site. CONCLUSION: The principles of compression anastomosis are better executed with the use of memory shape alloys. The promising results of this novel technique should encourage further studies of this technology.

Incidence and management of colonoscopic perforations: 8 years' experience.

AIM: To review the experience of a major medical teaching center with diagnostic and therapeutic colonoscopies and to assess the incidence and management of related colonic perforations. METHODS: All colonoscopies performed between January 1994 and December 2001 were studied. Data on patients, colonoscopic reports and procedure-related complications were collected from the departmental computerized database. The medical records of the patients with post procedural colonic perforation were reviewed. RESULTS: A total of 120067 colonoscopies were performed during the 8 years of the study. Seven colonoscopic perforations (4 females, 3 males) were diagnosed (0.058%). Five occurred during diagnostic and two during therapeutic colonoscopy. Six were suspected during or immediately after colonoscopy. All except one had signs of diffuse tenderness and underwent immediate operation with primary repair done in 4 patients. No deaths were reported. CONCLUSION: Perforation rate during colonoscopy is low. Nevertheless, it is a serious complication and its early recognition and treatment are essential to optimize outcome. In patients with diffuse peritonitis early operative intervention makes primary repair a safe option.

Colonic anastomosis performed with a memory-shaped device.

BACKGROUND: The present study was prompted by our previous successful experience with the compression anastomosis clip (CAC) on animals followed by a study on 20 patients scheduled for colonic resection. METHODS: Sixty patients with colonic cancer were assigned randomly to undergo an anastomosis either with the CAC or a stapler. To perform anastomosis with CAC, the 2 edges of the resected colon are aligned. Two 5-mm incisions are made close to the edges, through which (using a special applier) the CAC, after being cooled in ice water, is introduced in an open position. In response to the body temperature, the clip resumes its original (closed) position, thereby clamping the 2 bowel segments together. At the same time, a small scalpel incorporated in the applier makes a small incision through the clamped walls for the passage of gas and feces. The clip is detached from the applier to be left inside the intestine. The 2 5-mm incisions are sutured. The clip is expelled with the stool within 5 to 7 days, creating a perfect uniform compression anastomosis. RESULTS: Neither group had anastomotic complications such as leakage or obstruction. All the other parameters were better in the study group than in the control patients. CONCLUSIONS: The use of the CAC for colonic surgery is safe, simple, efficient, shortens operation time, and is almost what we call the "no-touch concept" in surgery and may decrease infection.

Cancer disease predictive diagnosis: BAT/CD3-positive lymphocytes in cancer patients.

BAT is an immune-activating monoclonal antibody produced against Daudi cell membranes and selected for stimulating lymphocyte proliferation. The anti-tumor activity of BAT is related to its immunostimulatory properties. Both T and NK cells mediate the anti-tumor activity of BAT. CD4-positive T cells respond to BAT activation by proliferation and INF-gamma production. The aim of the study was to assess the probability that the BAT monoclonal antibody binding capacity to T cells is a marker for different cancers. Human peripheral blood T cells from colon, breast and prostate cancer patients, as well as healthy volunteer donors, were tested for the percentage of binding to BAT mAb (BAT/CD3 cells) by FACS analysis. All patients were tested before undergoing surgery or treatment, and their diagnosis was confirmed by histology. The results showed that the percentage of BAT monoclonal antibody binding to CD3-positive T cells in the peripheral blood was different in cancer patients with diverse tumor types. We found that lymphocytes from the blood of healthy donors contained 25% BAT/CD3 cells. In colon and breast cancer patients, a significant decrease to 13 and 11% of BAT/CD3 cells was found. In contrast, these cells increased ><50% in patients with prostate cancer. These findings may have a potential diagnostic significance and also assist in the evaluation of strategies for the therapeutic use of BAT for different cancer patients.

Surgical clip found in duodenal ulcer after laparoscopic cholecystectomy.

The wide use of surgical clips in laparoscopic surgery has led to a variety of complications. We describe two cases in which a surgical clip was incorporated into a duodenal ulcer after laparoscopic cholecystectomy. The presenting symptom was acute gastrointestinal bleeding. Both patients were treated endoscopically, and the bleeding stopped after the clip was removed from the ulcer base. Although the mechanism by which a surgical clip migrates into the duodenum is unclear, we recommend meticulous Calot's triangle dissection and removal of any wandering or misplaced clips. Endoscopic removal is recommended when a surgical clip is discovered in a bleeding ulcer.

Risk factors for lymph node metastases in breast ductal carcinoma in situ with minimal invasive component.

HYPOTHESIS: Clinical and pathological variables may be predictors of axillary dissemination in T1mic and T1a breast carcinoma. DESIGN: Retrospective medical chart review. SETTING: University-affiliated tertiary referral center. PATIENTS: All patients diagnosed as having ductal carcinoma in situ (DCIS) with microinvasion between January 1, 1988, and December 30, 1998. MAIN OUTCOME MEASURES: Pathology slides were reviewed according to the 1997 Cancer Staging Manual put forth by the American Joint Committee on Cancer. The number of involved ducts was noted. Patients with no invasive component or invasive components larger than 5 mm were excluded. Pathological and clinical variables were analyzed for their effect on axillary lymph node metastases. RESULTS: The study group included 57 women aged 37 to 71 years (median, 60 years), 37 with T1mic disease and 20 with T1a. Modified radical mastectomy was performed in 29 patients (18 with T1mic and 11 with T1a) and breast-preserving surgery in 28 (19 with T1mic and 9 with T1a). Forty-three patients (28 with T1mic and 15 with T1a) underwent axillary lymph node dissection. Axillary involvement was detected in 3 patients in each group. Forty-seven patients received adjuvant therapy (radiotherapy alone, or with hormones or chemotherapy). Follow-up was 3 to 120 months (median, 40 months). One patient was unavailable for follow-up, another died of disseminated disease, and a third developed contralateral primary carcinoma. Comedo DCIS (P<.03) and the number of DCIS-involved ducts (P<.002) in the T1mic group, and nuclear grade 3 (P<.001) in both groups, were independent significant predictors of axillary metastases. CONCLUSIONS: The significant rate of axillary metastases in T1a and T1mic breast tumors makes axillary staging a must. High nuclear grade, comedo DCIS, and high number of DCIS-involved ducts may predict axillary metastasis and should be considered when axillary dissection is done selectively.

Colonic anastomosis with the nickel-titanium temperature-dependent memory-shape device.

BACKGROUND: This study was prompted by our successful experience with a compression anastomosis clip (CAC) in an animal model. METHODS: The study sample included 20 patients scheduled for colonic resections, of whom 10 underwent anastomosis with the CAC and 10 with staplers. RESULTS: Neither group had anastomotic or other complications, except for 1 patient in the CAC group in whom a subphrenic infected hematoma developed after left hemicolectomy with splenectomy. CONCLUSIONS: Our study demonstrates that this CAC is safe and simple to use, coming close to the "no touch surgery concept" and is of low cost compared with the staples used today.

Percutaneous transhepatic cholecystostomy: effective treatment of acute cholecystitis in high risk patients.

BACKGROUND: The mortality rate for cholecystectomy for acute cholecystitis in the elderly is 10% in low risk patients and increases threefold in high risk patients. Ultrasound-guided percutaneous transhepatic cholecystostomy may serve as a rapid and relatively safe tool to relieve symptoms of sepsis and decrease gallbladder distension. OBJECTIVE: To determine the safety and effectiveness of PTC in the treatment of acute cholecystitis in elderly debilitated high risk patients. METHODS: The study sample included 10 patients aged 63-88 (mean 77.6 years) with clinical and sonographic signs of acute cholecystitis for more than 48 hours (fever, white blood cells > 12,000/mm, positive Murphy sign and distended gallbladder) who underwent ultrasound guided PTC. All had severe underlying disease (coronary heart disease, renal failure, chronic obstructive pulmonary disease, and others) that places them at high risk for surgical intervention. RESULTS: Eight patients showed rapid regression of the clinical symptoms following PTC drainage. One patient with bacterial endocarditis was febrile for 5 days after catheter insertion, but with rapid resolution of the biliary colic and sepsis. One patient died from perforation of the gallbladder and small bowel. PTC catheters were withdrawn 3-25 days after the procedure and the patients remained free of biliary symptoms. Two patients underwent successful elective cholecystectomy 3 weeks later. CONCLUSION: PTC may be a safe and effective treatment for high risk elderly patients with acute cholecystitis. It can be followed by elective cholecystectomy if the underlying condition improves, as soon as the patient stabilizes and no sepsis is present, or by conservative management in high surgical-risk patients.

[Minimally invasive surgery for gastric cancer].

The use of laparoscopic surgery in the treatment of gastric cancer has not yet met with widespread acceptance. Hence, it should be regarded as still in the developmental phase. We present our experience with laparoscopic gastrectomy in four patients with gastric cancer during the last few months. The postoperative course was uneventful in all patients. It seems that although it remains a challenging procedure, laparoscopic gastrectomy should be considered as a possibility when planning this procedure.