Fibroblast matrix implants-a better alternative for incisional hernia repair?

The standard surgical procedure for abdominal hernia repair with conventional prosthetic mesh still results in a high recurrence rate. In the present study, we propose a fibroblast matrix implant (FMI), which is a three-dimensional (3D) poly-L-lactic acid scaffold coated with collagen (matrix) and seeded with fibroblasts, as an alternative mesh for hernia repair. The matrix was seeded with fibroblasts (cellularized) and treated with a conditioned medium (CM) of human Umbilical Cord Mesenchymal Stem Cells (hUC-MSC). Fibroblast proliferation and function were assessed and compared between treated with CM hUC-MSC and untreated group, 24 h after seeding onto the matrix (n= 3). To study the matricesin vivo,the hernia was surgically created on male Sprague Dawley rats and repaired with four different grafts (n= 3), including a commercial mesh (mesh group), a matrix without cells (cell-free group), a matrix seeded with fibroblasts (FMI group), and a matrix seeded with fibroblasts and cultured in medium treated with 1% CM hUC-MSC (FMI-CM group).In vitroexamination showed that the fibroblasts' proliferation on the matrices (treated group) did not differ significantly compared to the untreated group. CM hUC-MSC was able to promote the collagen synthesis of the fibroblasts, resulting in a higher collagen concentration compared to the untreated group. Furthermore, thein vivostudy showed that the matrices allowed fibroblast growth and supported cell functionality for at least 1 month after implantation. The highest number of fibroblasts was observed in the FMI group at the 14 d endpoint, but at the 28 d endpoint, the FMI-CM group had the highest. Collagen deposition area and neovascularization at the implantation site were observed in all groups without any significant difference between the groups. FMI combined with CM hUC-MSC may serve as a better option for hernia repair, providing additional reinforcement which in turn should reduce hernia recurrence.

Diagnostic performance of CT with Valsalva maneuver for the diagnosis and characterization of inguinal hernias

PURPOSE

Inguinal hernias are mainly diagnosed clinically, but imaging can aid in equivocal cases or for treatment planning. The purpose of this study was to evaluate the diagnostic performance of CT with Valsalva maneuver for the diagnosis and characterization of inguinal hernias.

METHODS

This single-center retrospective study reviewed all consecutive Valsalva-CT studies between 2018 and 2019. A composite clinical reference standard including surgery was used. Three blinded, independent readers (readers 1-3) reviewed the CT images and scored the presence and type of inguinal hernia. A fourth reader measured hernia size. Interreader agreement was quantified with Krippendorff's α coefficients. Sensitivity, specificity, and accuracy of Valsalva-CT for the detection of inguinal hernias was computed for each reader.

RESULTS

The final study population included 351 patients (99 women) with median age 52.2 years (interquartile range (IQR), 47.2, 68.9). A total of 381 inguinal hernias were present in 221 patients. Sensitivity, specificity, and accuracy were 85.8%, 98.1%, and 91.5% for reader 1, 72.7%, 92.5%, and 81.8% for reader 2, and 68.2%, 96.3%, and 81.1% for reader 3. Hernia neck size was significantly larger in cases correctly detected by all three readers (19.0 mm, IQR 13, 25), compared to those missed by all readers (7.0 mm, IQR, 5, 9; p < 0.001). Interreader agreement was substantial (α = 0.723) for the diagnosis of hernia and moderate (α = 0.522) for the type of hernia.

CONCLUSION

Valsalva-CT shows very high specificity and high accuracy for the diagnosis of inguinal hernia. Sensitivity is only moderate which is associated with missed smaller hernias.

Results of robotic TAPP and conventional laparoscopic TAPP in an outpatient setting: a cohort study in Switzerland

Purpose

Recently, robotic surgery has been increasingly performed in hernia surgery. Although feasibility and safety of robot-assisted inguinal hernia repair in an inpatient setting have been already shown, its role in outpatient hernia surgery has not yet been investigated. Thus, this study aimed to compare robot-assisted TAPP (r-TAPP) and conventional laparoscopic TAPP (l-TAPP) in an outpatient setting.

Methods

A prospective database of patients with inguinal hernia treated by l-TAPP or r-TAPP in an outpatient setting during a 1-year period was analyzed in a comparative cohort study. All patients underwent a check-up appointment with their surgeon within 3 days and 6 weeks postoperatively. Data on surgical time, perioperative complications, and postoperative pain were collected. Pain was recorded by using a Verbal Rating Scale (VRS).

Results

Overall, outpatient laparoendoscopic inguinal hernia repair was performed in 58 patients (29 l-TAPP; 29 r-TAPP). Mean age was 57 years (21–81), mean BMI 24.5 kg/m2 (19–33) with no differences between both groups. Most patients reported none or only a low postoperative pain level in both groups (89.6% in l-TAPP group; 100% in r-TAPP), while there was a trend for less pain after r-TAPP. In both groups, there was one case of postoperative hematoma, which was successfully treated by conservative means. No other complications occurred during follow-up in either group and there was no 30-day-readmission, no unplanned overstay or any 30-day mortality in the cohort.

Conclusion

Robot-assisted inguinal hernia surgery can be safely performed in an outpatient setting with a tendency to less pain when compared to the conventional laparoscopic technique. Cost-effectiveness and cost-coverage of outpatient robot-assisted inguinal hernia surgery must be further investigated in times of limited health cost resources and diagnosis-related medical reimbursements.

Online survey on factors influencing patients' motivation to undergo bariatric surgery

Given the worldwide increasing prevalence of severe obesity and considering the amount of scientific evidence demonstrating the beneficial effects of bariatric surgery (BS), it is surprising that only a fraction of patients with obesity undergo BS. We therefore conducted an anonymized online survey among individuals with a history of BS to understand factors influencing the deciding process leading to BS. Respondents were recruited on a voluntary basis from obesity-related social media groups between April and June 2020. The self-designed, non-validated questionnaire consisted of 20 questions and was open to any participants with a history of BS. Of 851 participants who started the survey, 665 completed the questionnaire (completion rate of 78.1%). Five years after BS, still 70% of the survey-participants were very satisfied or satisfied with the surgical result. However, the majority (73.3%) would have undergone BS earlier. The main motivation to choose BS was related to health status or quality of life. Important characteristics for a bariatric surgeon to obtain patients' trust are "taking time and listen" (74.7%), empathy (64%) and sympathy (56%). Post-operative satisfaction with the surgical outcome was high and long-lasting in this large cohort of BS patients. However, most participants would retrospectively have undergone BS earlier. The main reason to choose BS as treatment for their obesity were impaired physical health or reduced quality of life. Nearby location to patients' residence and availability of surgeons with empathy were decisive motives for bariatric centre selection.

How to Establish Benchmarks for Surgical Outcomes?: A Checklist Based on an International Expert Delphi Consensus

OBJECTIVE

To define a standardized methodology for establishing benchmarks for relevant outcomes in surgery.

SUMMARY BACKGROUND DATA

Benchmarking is an established tool to improve quality in industry and economics, and is emerging in assessing outcome values in surgery. Despite a recent 10-step approach to identify such benchmark values, a standardized and more widely agreed-on approach is still lacking.

METHODS

A multinational web-based Delphi survey with a focus on methodological requirements for establishing benchmarks for surgical outcomes was performed. Participants were selected among internationally renowned specialists in abdominal, vascular, and thoracic surgery. Consensus was defined as ≥70% agreement and results were used to develop a checklist to establish benchmarks in surgery.

RESULTS

Forty-one surgical opinion leaders from 19 countries and 5 continents were involved. Experts' response rates were 98% and 80% in rounds 1 and 2, respectively. Upon completion of the final Delphi round, consensus was successfully achieved for 26 of 36 items covering the following areas: center eligibility, validation of databases, patient cohort selection, procedure selection, duration of follow-up, statistical analysis, and publication requirements regarding center-specific outcomes.

CONCLUSIONS

This multinational Delphi survey represents the first expert-led process for developing a standardized approach for establishing benchmarks for relevant outcome measures in surgery. The provided consensual checklist customizes the methodology of outcome reporting in surgery and thus improves reproducibility and comparability of data and should ultimately serve to improve quality of care.

Defining Global Benchmarks in Elective Secondary Bariatric Surgery Comprising Conversional, Revisional, and Reversal Procedures

OBJECTIVE

To define "best possible" outcomes for secondary bariatric surgery (BS).

BACKGROUND

Management of poor response and of long-term complications after BS is complex and under-investigated. Indications and types of reoperations vary widely and postoperative complication rates are higher compared to primary BS.

METHODS

Out of 44,884 BS performed in 18 high-volume centers from 4 continents between 06/2013-05/2019, 5,349 (12%) secondary BS cases were identified. Twenty-one outcome benchmarks were established in low-risk patients, defined as the 75th percentile of the median outcome values of centers. Benchmark cases had no previous laparotomy, diabetes, sleep apnea, cardiopathy, renal insufficiency, inflammatory bowel disease, immunosuppression, thromboembolic events, BMI> 50 kg/m2 or age> 65 years.

RESULTS

The benchmark cohort included 3143 cases, mainly females (85%), aged 43.8 ± 10 years, 8.4 ± 5.3 years after primary BS, with a BMI 35.2 ± 7 kg/m2. Main indications were insufficient weight loss (43%) and gastro-esophageal reflux disease/dysphagia (25%). 90-days postoperatively, 14.6% of benchmark patients presented ≥1 complication, mortality was 0.06% (n = 2). Significantly higher morbidity was observed in non-benchmark cases (OR 1.37) and after conversional/reversal or revisional procedures with gastrointestinal suture/stapling (OR 1.84). Benchmark cutoffs for conversional BS were ≤4.5% re-intervention, ≤8.3% re-operation 90-days postoperatively. At 2-years (IQR 1-3) 15.6% of benchmark patients required a reoperation.

CONCLUSION

Secondary BS is safe, although postoperative morbidity exceeds the established benchmarks for primary BS. The excess morbidity is due to an increased risk of gastrointestinal leakage and higher need for intensive care. The considerable rate of tertiary BS warrants expertise and future research to optimize the management of non-success after BS.

Normal width of the linea alba, prevalence, and risk factors for diastasis recti abdominis in adults, a cross-sectional study

Aim

The prevalence and definition of diastasis recti abdominis (DRA) is under debate. This retrospective cross-sectional study evaluated the interrectal distance and the prevalence of DRA in computed tomography (CT) in an asymptomatic population.

Materials and methods

Patients undergoing CT scans for suspected appendicitis or kidney stones from 01/2016 to 12/2018 were screened retrospectively to participate. A study population with equal distribution according to gender and age (18–90 years) was generated (n = 329 patients) and the interrectal distance was measured at six reference points.

Results

DRA (defined as > 2 cm at 3 cm above the umbilicus) was present in 57% of the population. The 80th percentile of the interrectal distance was 10 mm at the xiphoid (median 3 mm, 95% confidence interval (CI) 0–19 mm), 27 mm halfway from xiphoid to umbilicus (median 17 mm, 95% CI 0–39 mm), 34 mm at 3 cm above the umbilicus (median 22 mm, 95% CI 0–50 mm), 32 mm at the umbilicus (median 25 mm, 95% CI 0–45 mm), 25 mm at 2 cm below the umbilicus (median 14 mm, 95% CI 0–39 mm), and 4 mm halfway from umbilicus to pubic symphysis (median 0 mm, 95% CI 0–19 mm). In the multivariate analysis, higher age (p = 0.001), increased body mass index (p < 0.001), and parity (p < 0.037) were independent risk factors for DRA, while split xiphoid, tobacco abuse, and umbilical hernia were not.

Conclusion

The prevalence of DRA is much higher than commonly estimated (57%). The IRD 3 cm above the umbilicus may be considered normal up to 34 mm. To avoid over-treatment, the definition of DRA should be revised.

Defining global benchmarks in elective secondary bariatric surgery comprising conversional, revisional and reversal procedures

Objective

Management of poor response and of long-term complications after bariatric surgery (BS) is complex and under-investigated. Indications and types of reoperations vary widely and postoperative complication rates are higher compared to primary BS. Benchmarking uses best performance in a given field as reference point for improvement. Our aim was to define ‘‘best possible’’ outcomes for elective secondary BS.

Methods

The establishment of benchmarks in secondary BS followed a standardized methodology, based on recommendations of a Delphi consensus panel of experts. This multicenter study analyzed patients undergoing elective secondary BS in 18 high-volume centers on 4 continents from 06/2013 to 05/2019. Twenty-one outcome benchmarks were established in low-risk patients, defined as the 75th percentile of the median outcome values of the centers. Benchmark cases had no: previous laparotomy, diabetes, sleep apnea, cardiopathy, renal insufficiency, inflammatory bowel disease, immunosuppression, history of thromboembolic events, BMI&gt;50kg/m2 or age&gt;65 years. Descriptive statistics, multivariate logistic regression and data visualization were performed using the R software.

Results

Out of 44’884 elective bariatric procedures performed in the participating centers, 5’328 secondary BS cases were identified. The benchmark cohort included 3143 cases, mainly females (85%), aged 43.8±10 years, 8.4±5.3 years after primary BS, with a body mass index 35.2±7kg/m2. Main indications were insufficient weight loss (43%) and gastro-esophageal reflux disease/dysphagia (25%). 90-days postoperatively, 14.57% of benchmark patients presented ≥1 complication, mortality was 0.06% (n = 2). Significantly higher morbidity was observed in non-benchmark cases (OR 1.36) and after conversional or revisional procedures with gastrointestinal suture/stapling (OR 1.7). Benchmark cutoffs at 90-days postoperatively were ≤5.8% re-intervention and ≤8.8% re-operation rate. At 2-years (IQR 1-3) 15.6% of benchmark patients required a reoperation.

Conclusion

Secondary BS is safe, although postoperative morbidity exceeds the established benchmarks for primary BS. The excess morbidity is due to an increased risk of gastrointestinal leakage and higher need for intensive care. The considerable rate of tertiary BS warrants expertise and future research to optimize the management of non-success after BS.

Sleeve gastrectomy or gastric bypass: a "post-code" lottery? A comprehensive national analysis of the utilization of bariatric surgery in Switzerland between 2011-2017

BACKGROUND

Sleeve gastrectomy (SG) recently became the most frequently performed bariatric surgery (BS) worldwide, overtaking the long-time standard Roux-en-Y gastric bypass (RYGB). Main indications for one or the other procedure show large inter-center variations and warrant further investigations.

OBJECTIVES

The aim of this study was to identify the influencers of primary BS selection in Switzerland.

SETTING

Switzerland.

METHODS

Retrospective analysis of all hospitalizations in Switzerland January 1, 2011 through December 31, 2017 with anonymized data provided by the Swiss Federal Statistical Office. BS procedures were identified based on ICD-10 and national surgical codes. Statistical analyses were performed with R.

RESULTS

During the study period 27,375 BS were performed. The annual BS caseload doubled over time, whereas inpatient complications decreased (∼-33%). RYGB was the prevailing procedure, although its annual proportion decreased from 80% to 70% over 7 years. Meanwhile, use of SG increased from 14% to 23%. Primary RYGB and SG had similar rates of inpatient mortality (∼.05%) and morbidity (8.0 versus 7.4%, P =.148), with the exception of higher ileus rates following RYGB (.7 versus .1%, P < .001). Patient-related factors favoring the indication of SG were male sex, extremes of age, and metabolic co-morbidities , while gastroesophageal reflux disease and private insurance-favored RYGB. Strikingly, differences between geographic regions outweighed patient-related factors in procedure selection: inhabitants of German- and Italian-speaking areas had higher likelihood (OR 4.6; 3.9, P < .001) to receive SG than those in French-speaking areas.

CONCLUSION

Geographic differences in primary BS procedure selection indicate a lack of objective rationales. Long-term risk-benefit and cost-effectiveness analyses are needed to assist evidence-based decision making.

Roux-en-Y gastric bypass surgery changes fungal and bacterial microbiota in morbidly obese patients-A pilot study

The Roux-en-Y gastric bypass (RYGB) remains the most effective treatment for morbidly obese patients to lower body weight and improve glycemic control. There is recent evidence that the mycobiome (fungal microbiome) can aggravate disease severity in a number of diseases including inflammatory bowel disease (IBD), irritable bowel syndrome (IBS) and hepatitis; moreover, a dysbiotic fungal microbiota has been reported in the obese. We characterized fungal and bacterial microbial composition in fecal samples of 16 morbidly obese patients before and three months after RYGB surgery and compared with nine healthy controls. We found that RYGB surgery induced a clear alteration in structure and composition of the gut fungal and bacterial microbiota. Beta diversity analysis revealed significant differences in bacterial microbiota between obese patients before surgery and healthy controls (P < 0.005) and a significant, unidirectional shift in RYGB patients after surgery (P < 0.001 vs. before surgery). In contrast, there was no significant difference in fungal microbiota between groups but individually specific changes after RYGB surgery. Interestingly, RYGB surgery induced a significant reduction in fungal alpha diversity namely Chao1, Sobs, and Shannon diversity index (P<0.05, respectively) which contrasts the trend for uniform changes in bacteria towards increased richness and diversity post-surgery. We did not observe any inter-kingdom relations in RYGB patients but in the healthy control cohort and there were several correlations between fungi and bacteria and clinical parameters (P<0.05, respectively) that warrant further research. Our study identifies changes in intestinal fungal communities in RYGB patients that are distinct to changes in the bacterial microbiota.

Blurring the boundary between open abdomen treatment and ventral hernia repair

PURPOSE

Therapeutic approaches for septic open abdomen treatment remain a major challenge with many uncertainties. The most convincing method is vacuum-assisted wound closure with mesh-mediated fascia traction with a protective plastic sheet placed on the viscera. As this plastic sheet and the mesh must be removed before final fascial closure, such a technique only allows temporary abdominal closure. This retrospective study analyzes the results of a modification of this technique allowing final abdominal closure using an anti-adhesive permeable polyvinylidene fluoride (PVDF) mesh.

METHODS

The outcome of all consecutive patients with septic open abdomen treatment at one academic surgical department from January 2013 to June 2015 was retrospectively analyzed.

RESULTS

Retrospectively, 57 severely ill consecutive patients with septic open abdomen treatment with a 30-day mortality of 26% and a 2-year mortality of 51% were included in the study. In 26 patients, no mesh was implanted; in 31 patients, mesh implantation was done at median third-look laparotomy, median 5 days postoperative. Re-laparotomies after mesh implantation (median n = 2) revealed anastomotic leakage in 16% but no new bowel fistula. In 40% of those patients who had mesh implantation, fascia closure was not achieved and the mesh was left in place in a bridging position avoiding planned ventral hernia.

CONCLUSION

The application of an anti-adhesive PVDF mesh for fascia traction in vacuum-assisted wound closure of septic open abdomen is novel, versatile, and seems to be safe. It offers the highly relevant possibility for provisional and final abdominal closure.

[Complex Hernia Repair]

Complex Hernia Repair Abstract. Treatment of complex hernia is underestimated and remains a challenge. Often tailored surgical techniques are required. The anatomy of the abdominal wall is reconstructed and reinforced by the placement of a mesh. In this article current surgical techniques of abdominal wall reconstruction are discussed.

Gallbladder perforation by absorbable spiral tacker

INTRODUCTION

Mesh fixation with tacker systems is common in laparoscopic and open hernia repair. Complications due to absorbable tackers are rare and have not been described in the literature. However, we report a case of gallbladder erosion due to tacker dislocation.

METHODS

An open hernia repair was performed using an intraperitoneal onlay mesh for a recurrent parastomal hernia after two previous mesh repairs in a 67-year-old patient.

RESULTS

On postoperative day 2, the patient was reoperated because of a dislocated tacker that eroded and perforated the fundus region of the gallbladder. Putatively, tacker dislocation occurred owing to imbalanced traction forces. Initially, the mesh was fixed with absorbable tackers around the stoma on the right and transmuscular suture fixation was carried out on the left abdominal side. On revision surgery, tension forces to the right were therefore neutralised by additional transmuscular sutures on the right side.

CONCLUSIONS

Absorbable tackers in open hernia repair provide a safe and effective mesh fixation if tension forces are carefully avoided.

[Cytoreductive surgery and HIPEC: a curative strategy for primary and secondary peritoneal tumors]

In patients with peritoneal carcinomatosis, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) offers a chance for long term survival in well selected patients. During cytoreductive surgery, all macroscopically visible tumors needs to be resected before HIPEC is performed in the same procedure. The aim of HIPEC is eradication of microscopic tumor cells after radical surgery. Perioperative morbidity and mortality are comparable with other major surgical procedures. Patients with peritoneal carcinomatosis from tumors of the appendix, the colon or primary peritoneal mesothelioma are currently recommended for evaluation of CRS/HIPEC in an interdisciplinary setting.

Cosmesis and body image after single-port laparoscopic or conventional laparoscopic cholecystectomy: a multicenter double blinded randomised controlled trial (SPOCC-trial)

BACKGROUND

Emerging attempts have been made to reduce operative trauma and improve cosmetic results of laparoscopic cholecystectomy. There is a trend towards minimizing the number of incisions such as natural transluminal endoscopic surgery (NOTES) and single-port laparoscopic cholecystectomy (SPLC). Many retrospective case series propose excellent cosmesis and reduced pain in SPLC. As the latter has been confirmed in a randomized controlled trial, patient's satisfaction on cosmesis is still controversially debated.

METHODS/DESIGN

The SPOCC trial is a prospective, multi-center, double blinded, randomized controlled study comparing SPLC with 4-port conventional laparoscopic cholecystectomy (4PLC) in elective surgery. The hypothesis and primary objective is that patients undergoing SPLC will have a better outcome in cosmesis and body image 12 weeks after surgery. This primary endpoint is assessed using a validated 8-item multiple choice type questionnaire on cosmesis and body image. The secondary endpoint has three entities: the quality of life 12 weeks after surgery assessed by the validated Short-Form-36 Health Survey questionnaire, postoperative pain assessed by a visual analogue scale and the use of analgesics. Operative time, surgeon's experience with SPLC and 4PLC, use of additional ports, conversion to 4PLC or open cholecystectomy, length of stay, costs, time of work as well as intra- and postoperative complications are further aspects of the secondary endpoint. Patients are randomly assigned either to SPLC or to 4PLC. Patients as well as treating physicians, nurses and assessors are blinded until the 7th postoperative day. Sample size calculation performed by estimating a difference of cosmesis of 20% (alpha = 0.05 and beta = 0.90, drop out rate of 10%) resulted in a number of 55 randomized patients per arm.

DISCUSSION

The SPOCC-trial is a prospective, multi-center, double-blind, randomized controlled study to assess cosmesis and body image after SPLC.

TRIAL REGISTRATION

(clinicaltrial.gov): NCT 01278472.

Laparoscopic cholecystectomy in acute cholecystitis: indication, technique, risk and outcome

BACKGROUND

Laparoscopic cholecystectomy (LC) has become the treatment of choice for symptomatic cholelithiasis. However, the laparoscopic approach has remained controversial for patients with acute cholecystitis (AC) because of technical difficulties that, compared with open cholecystectomy (OC), might lead to higher complication rates, particularly common bile duct (CBD) injuries and infection.

METHODS

We reviewed recent clinical findings on feasibility, safety and potential benefits of LC in patients with AC. An electronic search using the PubMed and MEDLINE databases was performed using the terms laparoscopic cholecystectomy, open cholecystectomy and acute cholecystitis. Pertinent references from articles and books not identified by the search engines were also retrieved. Relevant surgical textbooks were also reviewed.

CONCLUSIONS

The early laparoscopic approach has been shown to be technically feasible and at least equally as safe as the open approach. However, extensive inflammation, adhesions and consequent increased oozing can make laparoscopic dissection of Calot's triangle and recognition of the biliary anatomy hazardous and difficult. Therefore, conversion to OC remains an important treatment option to secure patient safety in such difficult conditions. The question of whether intraoperative cholangiography (IOC) should be used routinely or only selectively has never been resolved. Proponents for each side have put forward compelling arguments.

Trans- and retroperitoneal endoscopic adrenalectomy: experience in 26 consecutive adrenalectomies

OBJECTIVE

To assess our current concept and results of transperitoneal laparoscopic adrenalectomy (TPLA) and retroperitoneal endoscopic adrenalectomy (ERA) for a variety of benign disorders of the adrenal glands.

BACKGROUND DATA

According to the literature, minimal invasive adrenalectomy has shown to be a safe and effective surgical alternative to open adrenalectomy. Both, transperitoneal and retroperitoneal endoscopic minimal invasive access are currently used for surgical removal of benign adrenal tumors. There is still some debate about the indications and the access used for a minimal invasive approach.

PATIENTS AND METHODS

Treatment and clinical outcome of all patients who underwent either transperitoneal laparoscopic or endoscopic retroperitoneal adrenalectomies for benign diseases from February 1997 to August 2002 were analyzed retrospectively.

RESULTS

Twenty-six minimal invasive adrenalectomies were performed in 23 patients with a mean age of 57 years. Whereas 11 patients underwent unilateral right- sided ERA, unilateral TPLA was performed in 9 patients on the left side. Three patients had bilateral TPLA. The mean operating time for unilateral ERA and TPLA was 114 and 79 min, respectively. Bilateral TPLA was prolonged to 223 min operating time. There were only two minor postoperative complications. The mean hospital stay for unilateral TPLA, ERA and bilateral TPLA was 4.7, 5 and 6 days, respectively. There was no mortality.

CONCLUSION

Both, ERA and TPLA are safe and clinically effective treatment modalities for benign disorders of the adrenal glands. We currently favor a transperitoneal laparoscopic approach for bilateral and left-sided adrenal tumors, whereas right-sided tumors <8 cm are removed by a retroperitoneal approach. Large right-sided tumors >8 cm are better removed by transperitoneal access.

Alterations on the 5' noncoding region of the BCL-6 gene are not correlated with BCL-6 protein expression in T cell non-Hodgkin lymphomas

The BCL-6 proto-oncogene is expressed in germinal center B lymphocytes, in their neoplastic counterparts, and in a subpopulation of germinal center and perifollicular T lymphocytes. Rearrangements and/or mutations of the 5' noncoding region of the bcl-6 gene have been demonstrated in a large majority of diffuse large B cell lymphomas. Some, but not all, of these genetic alterations lead to dysregulation of the protein. Recently, anaplastic large cell lymphomas with T and null cell phenotypes, as well as T lymphoblastic lymphomas, have also been reported to exhibit immunoreactivity to the anti-BCL-6 antibody. We collected 33 T cell non-Hodgkin lymphomas (T-NHLs) and analyzed their expression of the BCL-6 protein by immunohistochemistry and investigated the organization of the bcl-6 gene by Southern blot and single strand conformation polymorphism (SSCP). The expression of BCL-6 was demonstrated in 37.5% of lymphoblastic (LBL), 40% of anaplastic large cell (ALCL), and 33% of peripheral T cell lymphomas (PTCL). BCL-6-positive malignant cells exhibited the CD4+ or CD4+/CD8+ phenotype. The bcl-6 gene was in a germline configuration in all T-NHLs examined, and a mutation at the first exon-intron boundary region structure of the wild-type bcl-6 gene was detected in 3 of 12 PTCL. One case of PTCL with mutations of the 5' noncoding region expressed BCL-6. In conclusion, expression of the BCL-6 protein is demonstrable independently of bcl-6 alterations in T-NHLs. This further suggests that molecular mechanisms other than rearrangements and/or mutations of the 5' noncoding region of the bcl-6 gene can result in expression of the protein. Whether these lymphomas arose from T cells expressing BCL-6 or expressed BCL-6 as part of the malignant transformation process needs to be determined. Finally, structural alterations of bcl-6 are rare in T-NHLs, but mutations do occur in the 5' noncoding region. We suggest that expression of BCL-6 in T cells may facilitate lymphomagenesis by repressing critical cytokines and cell cycle regulators.

Effect of methylene blue on the disposition of ethanol

The effect of methylene blue on the disposition of ethanol was studied in rats and humans. Methylene blue increased the metabolism of [(14)C]ethanol to (14)CO(2) in isolated hepatocytes and in intact rats by 75% and 30%, respectively. In healthy volunteers, methylene blue did not affect the pharmacokinetics of ethanol and did not alleviate the ethanol-induced NAD redox changes as reflected by the increase in the [lactate]/[pyruvate] ratio.

Hodgkin's disease-like lymphoproliferative disorders in patients with different underlying immunodeficiency states

Epstein-Barr virus (EBV)-associated lymphoproliferative diseases are a frequent occurrence in immunodeficient patients. Most commonly seen are polymorphic B-cell lymphoproliferative disorders and malignant B-cell lymphomas. Classical Hodgkin's disease (HD), however, is rare in these patients. In the present study, we attempted to characterize cases resembling HD in patients with a variety of underlying immunodeficiency states using clinical aspects, immunohistochemistry, in situ hybridization, and polymerase chain reaction. All of the six cases that we investigated presented clinically with B symptoms and a short, devastating course. Histologically, they showed a lymphocytic depletion and multiple cells that resembled HD and Reed-Sternberg cells. Many of those were atypical blast cells that stained positively for B-cell surface antigens, such as CD20 and CD79a, whereas others were of the typical HD and Reed-Sternberg phenotype. Another frequent finding, especially in the extranodal sites, was a perivascular arrangement of large blast cells intermingled with small lymphoid cells. All of the cases were EBV-associated (proved latent membrane protein-1 immunohistochemical analysis, EBV-encoded RNA in situ hybridization, and polymerase chain reaction for subtypes A and B), with a frequent coinfection of type A and B. This was in contrast to ordinary HD, which is characterized by single infection of only one strain, i.e., the subtype A in Western countries. Three cases showed clonal B-cell populations, at least at terminal stages of the disease. We describe a lymphoproliferative disorder in immunodeficient patients with features of HD that, in some respects, resembles an EBV-driven lymphoproliferative disorder seen in cases of fatal infectious mononucleosis. We conclude that clinical and pathologic features of these disorders might cause some problems for histologic differential diagnosis and might represent a separate entity of their own in immunodeficient patients.

[Oral non-Hodgkin lymphomas and Epstein-Barr virus]

The oropharynx is the site of primary infection and further propagation of the Epstein-Barr virus (EBV). From here, virus is shed to saliva and infects peripheral blood lymphocytes. Eight oral Non-Hodgkin lymphomas (NHL) were investigated for the presence of EBV both by immunohistochemistry for the latent membrane protein (LMP) and a PCR-strategy for general and subtype-specific viral sequences. All but one NHL turned out to be negative both by LMP and PCR. EBV general sequences and of the two viral subtypes A and B were found in an HIV-1+ patient. It is concluded that it is not the localisation which predetermines NHLs to EBV-positivity but merely the underlying disease (this study) or the type of tumour (previous studies).