Evaluation of data quality in the Spanish EURECCA Esophagogastric Cancer Registry

BACKGROUND

Although the number of nationwide clinical registries in upper gastrointestinal cancer is increasing, few of them perform regular clinical audits. The Spanish EURECCA Esophagogastric Cancer Registry (SEEGCR) was launched in 2013. The aim of this study was to assess the reliability of the data in terms of completeness and accuracy.

METHODS

Patients who were registered (2014-2017) in the online SEEGCR and underwent esophagectomy or gastrectomy with curative intent were selected for auditing. Independent teams of surgeons visited each center between July 2018 and December 2019 and checked the reliability of data entered into the registry. Completeness was established by comparing the cases reported in the registry with those provided by the Medical Documentation Service of each center. Twenty percent of randomly selected cases per hospital were checked during on-site visits for testing the accuracy of data (27 items per patient file). Correlation between the quality of the data and the hospital volume was also assessed.

RESULTS

Some 1839 patients from 19 centers were included in the registry. The mean completeness rate in the whole series was 97.8% (range 82.8-100%). For the accuracy, 462 (25.1%) cases were checked. Out of 12,312 items, 10,905 were available for verification, resulting in a perfect agreement of 95% (87.1-98.7%). There were 509 (4.7%) incorrect and 35 (0.3%) missing entries. No correlation between hospital volume and the rate of completeness and accuracy was observed.

CONCLUSIONS

Our results indicate that the SEEGCR contains reliable data.

Extended intraoperative peritoneal lavage as prophylactic peritoneal recurrence for locally advanced gastric cancer: a prospective randomized trial

BACKGROUND

To demonstrate whether extensive intraoperative peritoneal lavage (EIPL) could yield better results in overall survival and less recurrence, regardless of peritoneal cytology, compared to standard peritoneal lavage (SPL).

METHODS

A prospective randomised multicenter study including 94 patients (47 per arm) to detect a 20% difference in 3-year overall survival in patients with locally advanced tumours without peritoneal carcinomatosis. Three samples of peritoneal fluid were obtained (at the beginning, the end of procedure and after the assigned peritoneal lavage). Clinicopathological and surgical data were analysed by group. Postoperative complications, location of recurrence and surgical approach were evaluated. Overall survival was calculated by the Kaplan-Meier method and the uni/multivariate analysis for prognostic factors was carried out using Cox regression analysis.

RESULTS

A total of 86 patients were analysed (4 excluded per group). No statistical differences were observed in clinicopathological or surgical data between groups, considering both groups well-balanced for analysis. Overall survival at 3 years was 64.3% for SPL vs. 62.3% for EIPL (p 0.421). Only three patients had at least one positive peritoneal cytology (1:2). There were no differences regarding postoperative complications (SPL: 37.2% vs. EIPL: 32.5%, p 0.65) or between location of recurrence and number of recurrences. The number of recurrences did not differ between surgical approaches, but locoregional and peritoneal recurrences were fewer with the laparoscopic approach (p 0.048).

CONCLUSIONS

The regular use of extensive peritoneal lavage in patients with locally advanced gastric cancer, regardless of peritoneal cytology, has not been effective as prophylaxis of peritoneal recurrence or better survival.

Prevalence and Virulence Genes of Shigella spp. Isolated from Patients with Diarrhea in Rosario, Argentina

The aim of this study was to determine the prevalence and virulence factors of Shigella species isolated from patients with diarrhea. Shigella species were isolated from 1,022 stool samples collected from different hospitals in Rosario, Argentina. The isolates were characterized using phenotypic tests, serotyping, and detection of virulence genes by PCR. One hundred strains (9.8% of samples collected) of Shigella were isolated. Shigella flexneri was the most frequently identified species (74%), followed by S. sonnei (26%). S. flexneri was also the predominant species isolated from children aged 6-14 years. These clinical strains of Shigella were then tested for the presence of ipaH, virA, ial, sen, and set using specific primers. virA was present in all strains, whereas ipaH was detected in 98% of strains and ial in 83%. sen was found in 71.6% of S. flexneri and 42.3% of S. sonnei isolates, and 41.9% of S. flexneri isolates were positive for set. Furthermore, 32.4% of S. flexneri isolates were positive for both set and sen. This study provides data on the prevalence and distribution of diverse Shigella strains.

The inhibitory effect of colloidal bismuth hydroxide gel on Escherichia coli O157:H7 and on the activity of Shiga toxins

BACKGROUND

Shiga toxin-producing Escherichia coli (STEC) is the causative agent of hemolytic uremic syndrome (HUS). Colloidal bismuth hydroxide gel (CBHG) is an anti-diarrheal and antisecretory compound, which does not inhibit gastrointestinal motility and reaches an in vivo gut concentration of 10.8 mg/ml of bismuth. Its action on bacteria has not been studied. We analyzed its inhibitory effects on STEC, as well as the deactivation of the Shiga toxin (Stx) and its ability to block the spread of genes encoding Stx. We determined a minimum inhibitory concentration and bactericidal concentration for the STEC O157:H7 strain (EDL933), with CBHG and Chobet® bismuth cream with pectin (CBCHP). We analyzed its effect on Stx by means of cytotoxicity assay and ELISA, as well as its effect on the free 933 W Stx phage.

RESULTS

Effect on the EDL933 strain: CBHG: MIC 10 mg/ml of bismuth.

CBCHP

MIC 6 mg/ml and MBC 15 mg/ml of bismuth. Effect on EDL933 virulence factors: significant decrease in active Stx and 933 W Stx phage titer. ELISA did not find significant differences with treatment.

CONCLUSIONS

The results obtained may be useful in the development of new therapeutic strategies based on the use of CBHG to prevent or improve the prognosis of HUS, as it can be used to control STEC infections.

Phage biocontrol of enteropathogenic and shiga toxin-producing Escherichia coli in meat products

Ten bacteriophages were isolated from faeces and their lytic effects assayed on 103 pathogenic and non-pathogenic Enterobacteriaceae. Two phages (DT1 and DT6) were selected based on their host ranges, and their lytic effects on pathogenic E. coli strains inoculated on pieces of beef were determined. We evaluated the reductions of viable cells of Escherichia coli O157:H7 and non-O157 Shiga toxigenic E. coli strains on meat after exposure to DT6 at 5 and 24°C for 3, 6, and 24 h and the effect of both phages against an enteropathogenic E. coli strain. Significant viable cell reductions, compared to controls without phages, at both temperatures were observed, with the greatest decrease taking place within the first hours of the assays. Reductions were also influenced by phage concentration, being the highest concentrations, 1.7 × 10¹⁰ plaque forming units per milliliter (PFU/mL) for DT1 and 1.4 × 10¹⁰ PFU/mL for DT6, the most effective. When enteropathogenic E. coli and Shiga toxigenic E. coli (O157:H7) strains were tested, we obtained viable cell reductions of 0.67 log (p = 0.01) and 0.77 log (p = 0.01) after 3 h incubation and 0.80 log (p = 0.01) and 1.15 log (p = 0.001) after 6 h. In contrast, all nonpathogenic E. coli strains as well as other enterobacteria tested were resistant. In addition, phage cocktail was evaluated on two strains and further reductions were observed. However, E. coli bacteriophage insensitive mutants (BIMs) emerged in meat assays. BIMs isolated from meat along with those isolated by using the secondary culture method were tested to evaluate resistance phenotype stability and reversion. They presented low emergence frequencies (6.5 × 10⁻⁷–1.8 × 10⁻⁶) and variable stability and reversion. Results indicate that isolated phages were stable on storage, negative for all the virulence factors assayed, presented lytic activity for different E. coli virotypes and could be useful in reducing Shiga toxigenic E. coli and enteropathogenic E. coli viable cells in meat products.

Profiling of dihydroorotate dehydrogenase, p38 and JAK inhibitors in the rat adjuvant-induced arthritis model: a translational study

BACKGROUND AND PURPOSE

Translational animal models are essential in the prediction of the efficacy and side effects of new chemical entities. We have carried out a thorough study of three distinct disease-modifying antirheumatic drugs (DMARDs) in an adjuvant-induced arthritis (AIA) model in the rat and critically appraised the results in the context of the reported clinical experience in rheumatoid arthritis (RA) patients.

EXPERIMENTAL APPROACH

Teriflunomide - a dihydroorotate dehydrogenase (DHODH) inhibitor; AL8697 - a selective p38 MAPK inhibitor; and tofacitinib - a Janus kinase (JAK) inhibitor; were selected as representatives of their class and dose-response studies carried out using a therapeutic 10-day administration scheme in arthritic rats. Paw swelling and body weight were periodically monitored, and joint radiology and histology, lymph organ weight and haematological and biochemical parameters evaluated at study completion.

KEY RESULTS

All three drugs demonstrated beneficial effects on paw swelling, bone lesions and splenomegalia, with p38 inhibition providing the best anti-inflammatory effect and JAK inhibition the best DMARD effect. Leukopenia, body weight loss and gastrointestinal toxicity were dose-dependently observed with teriflunomide treatment. p38 MAPK inhibition induced leukocytosis and increased total plasma cholesterol. JAK inhibition, normalized platelet, reticulocyte and neutrophil counts, and alanine aminotransferase (ALT) levels while inducing lymphopenia and cholesterolemia.

CONCLUSIONS AND IMPLICATIONS

This multiparametric approach can reveal specific drug properties and provide translational information. Whereas the complex profile for p38 inhibition in AIA is not observed in human RA, immunosuppressants such as DHODH and JAK inhibitors show DMARD properties and side effects seen in both AIA and RA.

Phase II trial of preoperative chemoradiotherapy with oxaliplatin, cisplatin, and 5-FU in locally advanced esophageal and gastric cancer

BACKGROUND

Based on a phase I study showing the feasibility of combining of oxaliplatin, cisplatin, and 5-fluorouracil (5-FU) (OCF) with radiation therapy (RT) in esophageal cancer, the efficacy of this regimen in esophageal, gastroesophageal (GE), and gastric (G) cancer was assessed in this phase II multicenter study.

PATIENTS AND METHODS

Patients with resectable tumors were eligible. Treatment included two cycles of oxaliplatin 85 mg/m(2), cisplatin 55 mg/m(2), and continuously infused 5-FU 3 g/m(2) in 96 h and concurrent RT (45 Gy), followed by surgery after 6-8 weeks. Primary end point was complete pathologic response (pCR).

RESULTS

Forty-one patients were enrolled. Tumor location was esophagus 39% (squamous 10/adenocarcinoma 6), GE junction 32%, and stomach 29%. G3-G4 adverse events included asthenia (27%) and neutropenia (14%). One toxic death occurred. Thirty-one patients (75.6%) underwent surgery (R0 in 94%). Pathologic response was achieved in 58% of patients, with pCR in 50% and 16% of esophageal and GE/G cancer, respectively. pCR was achieved in 67% of squamous cell carcinoma. Survival: median follow-up, 50.4 months; median progression-free survival and overall survival were 23.2 and 28.4 months, respectively.

CONCLUSION

Preoperative OCF plus RT showed an acceptable toxicity and promising activity especially in squamous cell esophageal cancer.

Unusual upper gastrointestinal diseases associated with achalasia: laparoscopic approach

BACKGROUND

As a result of the high success rate associated with the laparoscopic approach for achalasia, surgery for the disease has become the treatment of choice in recent years. With the greater number of patients undergoing surgery, surgeons may encounter other upper gastroesophageal illnesses associated with achalasia, and these may require evaluation for simultaneous surgical treatment. This study aimed to evaluate the incidence of gastroesophageal diseases associated with achalasia, and to determine the possibility for simultaneous management using the laparoscopic approach.

METHODS

From January 1999 to May 2006, 81 patients were referred from the Service of Gastroenterology to the Service of General and Digestive Surgery as candidates for the surgical management of achalasia. Data for this group were recorded prospectively in laparoscopic surgery databases at the Hospital Sant Pau and the Hospital de Igualada. A total of 78 patients underwent laparoscopic Heller myotomy with gastric fundoplication.

RESULTS

In 8 of 81 patients, nine additional gastroesophageal diseases (11.1%) were found: three cases of pseudoachalasia (3.7%), three cases of paraesophageal hiatal hernia (3.7%), two cases of esophageal diverticulum (2.5%), and one case of gastric volvulus (1.2%). Pseudoachalasia was diagnosed for three patients. The diagnosis was made preoperatively for one of these patients. For the other two patients, an adenocarcinoma arising from the gastroesophageal junction was diagnosed during the laparoscopy. In three cases, a paraesophageal hiatal hernia was found and treated by laparoscopic Heller myotomy, sac excision, hiatal closure, and posterior fundoplication. Esophageal diverticulectomy was performed for one patient. Another patient presented with an organoaxial gastric volvulus associated with achalasia, for which laparoscopic Heller myotomy, posterior fundoplication, and anterior gastropexy were performed. The median follow-up period was 39 months, with no recurrence.

CONCLUSIONS

Despite their infrequency, several gastroesophageal diseases may be found in association with achalasia. Laparoscopic surgery may be useful for the diagnosis and/or treatment of both diseases.

Aryloxoalcanoic compounds induce resistance to antibiotic therapy in urinary tract infection caused by Escherichia coli

Clofibric acid (CL) is a compound used to control hypertriglyceridemia, and ethacrynic acid (ET) is administered to enhance diuresis. These compounds are structurally analogous to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), as they have a chlorinated phenoxy moiety. As these agents are mainly excreted by the renal route, they could potentially coexist with Escherichia coli in the urinary tract of infected patients. Induction of the in vitro resistance of E. coli to hydrophilic antibiotics was determined by increasing the values of the minimum inhibitory concentration (2-40-fold). These results correlated with drastically inhibited expression of the hydrophilic bacterial channel OmpF. In vivo assays were performed in ascending urinary tract infection in female BALB/c mice. Treatment with the hydrophilic antibiotic cephalexin 25 mg kg(-1) day(-1) by the oral route diminished renal infection. The CFU mean values in the kidneys were between 75% and 89% lower than those in animals without treatment. Simultaneous exposure to CL (at a therapeutic dose, 28.6 mg kg(-1) day(-1)) did not change the effect of the treatment. In contrast, ET at 2.9 mg kg(-1) day(-1) or 2,4-D at 70 mg kg(-1) day(-1) inhibited the antibiotic therapeutic effect. Moreover, 2,4-D dramatically increased bacterial infection after 9 days of exposure.

Predictive factors for successful laparoscopic splenectomy in immune thrombocytopenic purpura: study of clinical and laboratory data

BACKGROUND

Laparoscopic splenectomy (LS) offers better short-term results than open surgery for the treatment of immune thrombocytopenic purpura (ITP), but long-term follow-up is required to ensure its efficacy. The remission rate after splenectomy ranges from 49 to 86% and the factors that predict a successful response to surgical management have not been clearly defined. The goal of this study was to determine the preoperative factors that predict a successful outcome following LS.

METHODS

From February 1993 to December 2003, LS was consecutively performed in a series of 119 nonselected patients diagnosed with ITP (34 men and 85 women; mean age, 41 years), and clinical results were prospectively recorded. Postoperative follow-up was based on clinical records, follow-up data provided by the referring hematologist, and a phone interview with the patient and/or relative. Univariate and multivariate analyses were performed for clinical preoperative variables to identify predictive factors of success following LS.

RESULTS

Over a mean period of 33 months, 103 patients (84%) were available for follow-up with a remission rate of 89% (92 patients, 77 with complete remission with platelet count > 150,000). Eleven patients did not respond to surgery (platelet count < 50,000). Mortality during follow-up was 2.5% (two cases not related to hematological pathology and one case without response to splenectomy). Preoperative clinical variables evaluated to identify predictive factors of response to surgery were sex, age, treatment (corticoids alone or associated with Ig or chemotherapy), other immune pathology, duration of disease, and preoperative platelet count. In a subgroup of 52 patients, we also evaluated the type of autoantibodies and corticoid doses required to maintain a platelet count > 50,000. Multivariate analysis showed that none of the variables evaluated could be considered as predictive factors of response to LS due to the high standard error.

CONCLUSION

Long-term clinical results show that LS is a safe and effective therapy for ITP. However, a higher number of nonresponders is needed to determine which variables predict response to LS for ITP.

Occurrence of non-O157 shiga toxin-producing Escherichia coli in ready-to-eat food from supermarkets in Argentina

Between June 2000 and December 2001, 500 food samples were collected from supermarkets and shops selling ready-to-eat food in Rosario, Argentina, and examined for Escherichia coli. Forty-nine E. coli isolates from food samples were further characterized for virulence genes by multiplex polymerase chain reaction (PCR) targeting the stx1, stx2, stx2e, eaeA, CNF1, CNF2, Einv, LTI, STI, and STII genes in four groups. Out of 49 E. coli isolates screened by multiplex PCR, only 10 possessed Shiga toxin genes, stx1 and stx2 genes and none possessed the other genes. The Shiga toxin positive E. coli strains (STEC) were isolated from soft, cottage cheeses, chicken with sauce and vegetables mayonase. These E. coli isolates were serogrouped and belonged to O18 (two strains), O8, O57w, O79, O44, and O128; three strains were untypeable. Pulsed-field gel electrophoresis (PFGE) with XbaI generated a unique profile for each, having 10-15 bands ranging from 50 to 500 kb, except that strain ARG 20 generated small bands and was partly degraded. These strains are potential foodborne pathogens and their presence in ready-to-eat food illustrates the need to keep a careful watch for the source of pathogens and then develop methods to control them.

Immediate peritoneal response to bacterial contamination during laparoscopic surgery

BACKGROUND

Several studies have shown that laparoscopic surgery (LS) minimizes surgical trauma and the immune function is better preserved. Another major advantage of LS is the lower incidence of septic complications. However, several in vitro studies have shown that CO(2) severely impairs macrophage physiology. In theory, this would reduce the ability to respond to peritoneal contamination. However, there is some controversy in view of the evidence of a better preserved peritoneal response to sepsis. This study analyzed the early response of the peritoneum to contamination in a CO(2) ambience.

METHODS

A total of 192 CD-1 mice were distributed in three groups: group 1, laparotomy (LAP, n = 64); group 2, CO(2) laparoscopy (CO(2)-LC, n = 64); and group 3, wall lift laparoscopy (WL-LC, n = 64). Mice in each group were randomized to receive 1 ml of Escherichia coli suspension (1 x 10(4) colony-forming units/ml) or saline. Peritoneal fluid was obtained at 1.5, 3, 6, and 12 h after surgery. Monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6), and prostaglandin E(2) (PGE(2)) were measured.

RESULTS

MCP-1 levels were significantly greater and higher earlier in group 2 (CO(2)-LC) than in group 1 (LAP) (p < 0.007). Simultaneously, the increment in the traction group (WL-LC, group 3) was significantly higher (p < 0.002) than after laparotomy, with no differences in group 2 (CO(2)-LC). When a contamination was added to the laparotomy subgroup, there was a significant increase compared to the group without contamination (p < 0.5). MCP-1 modifications after contamination in the LAP group were statistically significant and appeared later than in the WL-LC (p < 0.002) and CO(2)-LC groups (p < 0.02). For IL-6, the three models presented a significant increase in the noncontaminated groups. This occurred significantly later in the LAP group. Simultaneously, the increase in IL-6 occurred earlier and was significantly higher in the WL-LC group compared to the LAP group (p < 0.003), without differences between CO(2)-LC and wall lift groups. Significant differences between contaminated and noncontaminated subgroups were only observed in the LC-CO(2) groups. When contaminated, the traction model sustained a higher and earlier rise in IL-6 levels compared to the LAP and LC-CO(2) groups (p < 0.001). For PGE(2), The three models showed a significant increase in PGE(2) levels in the noncontaminated groups. However, there were no significant differences between them. In the contaminated groups, there was no statistical difference between the groups.

CONCLUSION

Despite a transient impairment of the immediate peritoneal response to a septic challenge, the degree of injury with LS is lower than that with open surgery, and abdominal infection can therefore be better controlled.

Long-term outcome after laparoscopic splenectomy related to hematologic diagnosis

BACKGROUND

Laparoscopic splenectomy (LS) has been demonstrated as an effective and safe treatment for hematological disorders requiring spleen removal, especially in cases of normal-sized spleens. However, although results are promising, long-term outcome data are lacking. We reviewed our clinical experience with LS in a series of 255 cases, with particular attention to the long-term outcome related to the disease process requiring LS.

METHODS

From February 1993 to October 2003, LS was attempted in 255 patients (100 males and 155 females with a mean age of 45 +/- 19 years) and clinical information was recorded in a prospective database. Indications for splenectomy included idiopathic thrombocytopenic purpura (ITP) (n = 115), HIV-ITP (n = 9), Evans syndrome (n = 6), autoimmune hemolytic anemia (AIHA) (n = 13), hereditary spherocytosis (HS) (n = 19), hematologic malignancy (n = 66), thrombotic thrombocytopenic purpura (n = 1), and others (n = 26). Long-term postoperative follow-up evaluation was obtained through clinical notes, follow-up visits by the referring hematologist, and by phone interviews both with patients and with the referring hematologist.

RESULTS

A total of 186 patients (73%) were available for a mean follow-up of 35 months (range, 1-104). Of the ITP patients, 87 (76%) were followed up, with a remission rate of 89% (complete remission in 75%). A similar remission rate was observed in ITP-HIV; in patients available for follow-up (78%), complete remission was achieved in 83%. In Evans, complete remission was achieved in all patients available for follow-up (67%). Clinical response for hemolytic disease ranged between 70% for AIHA and 100% for HS. In the malignant group, the late mortality rate was 22%. The mortality rate in the miscellaneous group was 5%. No cases of splenectomy-related sepsis occurred during follow-up.

CONCLUSIONS

LS offers advantages for all types of splenic diseases requiring surgery. It provides not only good clinical short-term outcome but also satisfactory long-term hematological results.

Effect of ciprofloxacin on adhesive properties of non-P mannose-resistant uropathogenic Escherichia coli isolates

The influence of sub-MIC of ciprofloxacin on the surface properties of 25 non-P mannose-resistant uropathogenic Escherichia coli (UPEC) strains was studied. Thirteen isolates responded to antibiotic treatment with an increase in haemagglutination titre and/or surface hydrophobicity, which correlated with a higher expression of surface proteins. Only UPEC strains with ciprofloxacin-enhanced hydrophobicity increased their adhesiveness to urinary catheters that correlated, in one analysed case, with a dramatic increase in the number of fimbriae peripherally located. The overall results indicate that sub-MICs of ciprofloxacin could increase the adhesiveness, and hence the risk of colonization by UPEC strains expressing mannose-resistant adhesins different from type P.

Differential localisation of GFP fusions to cytoskeleton-binding proteins in animal, plant, and yeast cells. Green-fluorescent protein

The structure and functioning of the cytoskeleton is controlled and regulated by cytoskeleton-associated proteins. Fused to the green-fluorescent protein (GFP), these proteins can be used as tools to monitor changes in the organisation of the cytoskeleton in living cells and tissues in different organisms. Since the localisation of a specific cytoskeleton protein may indicate a particular function for the associated cytoskeletal element, studies of cytoskeleton-binding proteins fused to GFP may provide insight into the organisation and functioning of the cytoskeleton. In this article, we focused on two animal proteins, human T-plastin and bovine tau, and studied the distribution of their respective GFP fusions in animal COS cells, plant epidermal cells (Allium cepa), and yeast cells (Saccharomyces cerevisiae). Plastin-GFP localised preferentially to membrane ruffles, lamellipodia and focal adhesion points in COS cells, to the actin filament cytoskeleton within cytoplasmic strands in onion epidermal cells, and to cortical actin patches in yeast cells. Thus, in these 3 very different types of cells plastin-GFP associated with mobile structures in which there are high rates of actin turnover. Chemical fixation was found to drastically alter the distribution of plastin-GFP. Tau-GFP bound to microtubules in COS cells and onion epidermal cells but failed to bind to yeast microtubules. Thus, animal and plant microtubules appear to have a common tau binding site which is absent in yeast. We conclude that the study of the distribution patterns of microtubule- and actin-filament-binding proteins fused to GFP in heterologous systems should be a valuable tool in furthering our knowledge about cytoskeleton function in eukaryotic cells.

Activation of multiple antibiotic resistance in uropathogenic Escherichia coli strains by aryloxoalcanoic acid compounds

Clofibric and ethacrynic acids are prototypical pharmacological agents administered in the treatment of hypertrigliceridemia and as a diuretic agent, respectively. They share with 2,4-dichlorophenoxyacetic acid (the widely used herbicide known as 2,4-D) a chlorinated phenoxy structural moiety. These aryloxoalcanoic agents (AOAs) are mainly excreted by the renal route as unaltered or conjugated active compounds. The relatedness of these agents at the structural level and their potential effect on therapeutically treated or occupationally exposed individuals who are simultaneously undergoing a bacterial urinary tract infection led us to analyze their action on uropathogenic, clinically isolated Escherichia coli strains. We found that exposure to these compounds increases the bacterial resistance to an ample variety of antibiotics in clinical isolates of both uropathogenic and nonpathogenic E. coli strains. We demonstrate that the AOAs induce an alteration of the bacterial outer membrane permeability properties by the repression of the major porin OmpF in a micF-dependent process. Furthermore, we establish that the antibiotic resistance phenotype is primarily due to the induction of the MarRAB regulatory system by the AOAs, while other regulatory pathways that also converge into micF modulation (OmpR/EnvZ, SoxRS, and Lrp) remained unaltered. The fact that AOAs give rise to uropathogenic strains with a diminished susceptibility to antimicrobials highlights the impact of frequently underestimated or ignored collateral effects of chemical agents.

Human papillomavirus E6E7-mediated adenovirus cell killing: selectivity of mutant adenovirus replication in organotypic cultures of human keratinocytes

Replication-competent adenoviruses are being investigated as potential anticancer agents. Exclusive virus replication in cancer cells has been proposed as a safety trait to be considered in the design of oncolytic adenoviruses. From this perspective, we have investigated several adenovirus mutants for their potential to conditionally replicate and promote the killing of cells expressing human papillomavirus (HPV) E6 and E7 oncoproteins, which are present in a high percentage of anogenital cancers. For this purpose, we have employed an organotypic model of human stratified squamous epithelium derived from primary keratinocytes that have been engineered to express HPV-18 oncoproteins stably. We show that, whereas wild-type adenovirus promotes a widespread cytopathic effect in all infected cells, E1A- and E1A/E1B-deleted adenoviruses cause no deleterious effect regardless of the coexpression of HPV18 E6E7. An adenovirus deleted in the CR2 domain of E1A, necessary for binding to the pRB family of pocket proteins, shows no selectivity of replication as it efficiently kills all normal and E6E7-expressing keratinocytes. Finally, an adenovirus mutant deleted in the CR1 and CR2 domains of E1A exhibits preferential replication and cell killing in HPV E6E7-expressing cultures. We conclude that the organotypic keratinocyte culture represents a distinct model to evaluate adenovirus selectivity and that, based on this model, further modifications of the adenovirus genome are required to restrict adenovirus replication to tumor cells.

Hand-assisted laparoscopic splenectomy

Hand-assisted laparoscopic surgery (HALS) permits recovery of the tactile sensation and facilitates manipulation of solid organs. Our preliminary experience in laparoscopic splenectomy (LS) shows its advantages, with a substantial reduction of operative time, while maintaining the advantages of a less aggressive surgical approach. The role of HALS in cases of splenomegaly or trauma seems to be clear. It can also be considered as an alternative to conventional conversion in cases of intraoperative complications or unclear anatomy. The role of HALS for normal-sized spleens is more controversial because there is a well-systematized, conventional LS technique available, which is followed by optimal clinical outcome LS in hands of a skilled surgeon.

Identification of a novel pathogen-responsive element in the promoter of the tobacco gene HSR203J, a molecular marker of the hypersensitive response

The tobacco gene, HSR203J, which is specifically activated during the early steps of incompatible plant/pathogen interactions has been shown to be a molecular marker of the hypersensitive response (HR). It constitutes an ideal model for the identification of HR-responsive cis-regulatory elements. As a first step in the promoter dissection, deletion mutants of the 5' flanking sequence of HSR203J fused to the GUS reporter gene were analyzed. Then, the construction and study of chimeric constructs containing HSR203J promoter fragments fused to a minimal promoter enabled us to identify a 28-bp regulatory element located between -106 and -79 upstream of the transcription initiation site. This element has been shown to be necessary and sufficient for transcriptional activation in response to pathogen. It contains a 10-bp palindrome followed by its imperfect repeat. The mutagenesis of these two sequence elements led to the identification of a 12-bp motif termed HSRE (HSR203 responsive element) responsible for the marked induction of the HSR203J gene during the HR. Since this DNA region did not show any homology with known regulatory sequences, this 12 bp motif corresponds to a novel cis-regulatory element.

Effect of 2,4-dichlorophenoxyacetic acid herbicide on escherichia coli growth, chemical composition, and cellular envelope

2,4-Dichlorophenoxyacetic acid (2,4-D) is a herbicide widely used in the world and mainly excreted by the renal route in exposed humans and animals. Herbicides can affect other nontarget organisms, such as Escherichia coli. We observed that a single exposure to 1 mM 2,4-D diminished growth and total protein content in all E. coli strains tested in vitro. In addition, successive exposures to 0.01 mM 2,4-D had a toxic effect decreasing growth up to early stationary phase. Uropathogenic E. coli adhere to epithelial cells mediated by fimbriae, adhesins, and hydrophobic properties. 2,4-D exposure of uropathogenic E. coli demonstrated altered hydrophobicity and fimbriation. Hydrophobicity index values obtained by partition in p-xylene/water were 300-420% higher in exposed cells than in control ones. Furthermore, values of hemagglutination titer, protein contents in fimbrial crude extract, and electron microscopy demonstrated a significant diminution of fimbriation in treated cells. Other envelope alterations could be detected, such as lipoperoxidation, evidenced by decreased polyunsaturated fatty acids and increased lipid degradation products (malonaldehyde), and motility diminution. These alterations decreased cell adherence to erythrocytes, indicating a diminished pathogenic capacity of the 2,4-D-exposed E. coli.

hxc2, an Arabidopsis mutant with an altered hypersensitive response to Xanthomonas campestris pv. campestris

A chemical mutagenized population of Arabidopsis Col-0-gl plants was screened for an altered hypersensitive response (HR) after spray inoculation with an HR-inducing isolate of Xanthomonas campestris pv. campestris (strain 147). Three classes of mutant were identified: those exhibiting an HR- phenotype or partial loss of HR; hyper-responsive mutants showing necrotic lesions rapidly leading to the collapse of leaves; and susceptible mutants. One mutant belonging to the susceptible class, hxc-2, was extensively characterized. The compatible phenotype observed several days after initiation of the interaction was confirmed by measurement of in planta bacterial growth and use of bacterial strains constitutively expressing the GUS reporter gene. In the same way, accumulation of autofluorescent compounds, salicylic acid production and defence gene expression in the mutant were found to be similar to that displayed by the susceptible ecotype. Inoculation of hxc-2 with different avirulent bacteria suggests that the mutation is specific for the interaction with the Xcc 147 strain, although the mutation has been shown to affect a single dominant locus, different from the resistance locus defined by genetic analysis of resistance to Xcc 147. Genetic mapping of the mutation indicated that it is located on chromosome III, defining a previously unknown resistance function in response to X. c. campestris.

Replicative adenoviruses for cancer therapy

Rapid advances are being made in the engineering of replication-competent viruses to treat cancer. Adenovirus is a mildly pathogenic human virus that propagates prolifically in epithelial cells, the origin of most human cancers. While virologists have revealed many details about its molecular interactions with the cell, applied scientists have developed powerful technologies to genetically modify or regulate every viral protein. In tandem, the limited success of nonreplicative adenoviral vectors in cancer gene therapy has brought the old concept of adenovirus oncolysis back into the spotlight. Major efforts have been directed toward achieving selective replication by the deletion of viral functions dispensable in tumor cells or by the regulation of viral genes with tumor-specific promoters. However, the predicted replication selectivity has not been realized because of incomplete knowledge of the complex virus-cell interactions and the leakiness of cellular promoters in the viral genome. Capsid modifications are being developed to achieve tumor targeting and enhance infectivity. Cellular and viral functions that confer greater oncolytic potency are also being elucidated. Ultimately, the interplay of the virus with the immune system will likely dictate the success of this approach as a cancer therapy.

Laparoscopic surgery and surgical infection

INTRODUCTION

It has been observed that the metabolic response to surgical injury is less after laparoscopic surgery than after open surgery. However, the effect of laparoscopic surgery on surgical infection has not been given much attention in the surgical literature, even though it may decrease the incidence of infectious complications. The objective of this study was to assess the influence that laparoscopic surgery has on surgical infection and to highlight certain controversial aspects.

METHODS

A review of the literature was undertaken to examine the relationship between laparoscopic surgery and surgical infection. This was achieved primarily by using PubMed Medline as a source of material.

RESULTS AND CONCLUSION

Laparoscopic surgery is associated with better preservation of the immune system than open surgery. This results in a decreased incidence of infectious complications. Although carbon dioxide pneumoperitoneum affects the peritoneal response to injury, it seems to have no harmful effect in terms of intra-abdominal infection. Nevertheless, at laparoscopic operation the virulence of intestinal micro-organisms should be recognized and, while knowing the advantages of minimally invasive surgery, the surgeon should consider the complexity of this technique. Furthermore, maintenance of laparoscopic instruments should be governed by the same norms as those used in open surgery; recommendations offered by the manufacturers should be respected.

Sustained high-level expression of full-length human factor VIII and restoration of clotting activity in hemophilic mice using a minimal adenovirus vector

The successful prophylactic treatment of hemophilia A by frequent infusions of plasma concentrates or recombinant factor VIII (hFVIII) indicates that gene therapy may be a potential alternative for the treatment of the disease. For efficient delivery and long-term expression of the hFVIII gene, a novel minimal adenovirus (mini-Ad) vector, MiniAdFVIII, has been developed. The vector is devoid of all viral genes and carries the full-length hFVIII cDNA under the control of the human 12.5-kb albumin promoter. The MiniAdFVIII vector was propagated with the assistance of an ancillary vector in 293 cells and was purified by CsCl banding. Sustained expression of hFVIII at physiologic levels (100-800 ng/mL) was achieved in mice after a single intravenous injection of MiniAdFVIII. The expressed hFVIII had a structure identical to that of recombinant hFVIII, as determined by Western blot analysis. The functionality of the protein was confirmed by the restoration of blood coagulation capacity in MiniAdFVIII-treated hemophilic mice, as determined by tail clipping observations. Although antivector or antihuman FVIII antibodies at various levels were detected, long-term expression of the transgene was observed in the mice that did not generate antibodies against the transgene product. The vector DNA persisted in the liver tissues of the mice with long-term expression. No significant histopathologic findings or toxicities were observed to be associated with the vector in the MiniAdFVIII-treated C57BL/6 mice. These results support the further development of MiniAdFVIII for clinical trials toward the treatment of hemophilia A.

Could age be an indication for laparoscopic colectomy in colorectal cancer?

BACKGROUND

The incidence of colorectal carcinoma increases in the elderly. Regardless of age as an isolated factor, postoperative complications represent the main factor in increasing hospital mortality.

METHODS

The aim of this study was to compare the short-term results (first 30 postoperative days) after laparoscopically assisted colectomy (LAC) and open segmental colectomy (OC) in colorectal carcinoma between two groups of patients, older than 70 and younger than 70 years of age. In the study from November 1993 to June 1998, 255 patients were evaluated to participate.

RESULTS

Peristalsis, oral intake, and discharge from the hospital occurred earlier in LAC than in OC treated patients, in the two age groups. The mean operative time was significantly longer in the LAC than in the OC patients in the two age groups. No differences were observed in morbidity between LAC and OC in the group younger than 70 years of age. However, the overall morbidity was significantly lower in the LAC group in patients older than 70 years. One patient in the LAC group older than 70 years died.

CONCLUSION

These results suggest that laparoscopically assisted colectomy may be particularly indicated in elderly patients.

Gene therapy for gliomas: molecular targets, adenoviral vectors, and oncolytic adenoviruses

Currently, most of the approved clinical gene therapy protocols involve cancer patients and several of the therapies are designed to treat brain tumors. Two factors promoting the use of gene therapy for gliomas are the failure and toxicity of conventional therapies and the identification of the genetic abnormalities that contribute to the malignancy of gliomas. During the malignant progression of astrocitic tumors several tumor suppressor genes are inactivated, and numerous growth factors and oncogenes are overexpressed progressively. Thus, theoretically, brain tumors could be treated by targeting their fundamental molecular defects, provided the gene-drug can be delivered to a sufficient number of malignant cells. However, gene therapy strategies have not been abundantly successful clinically, in part because the delivery systems are still imperfect. In the first part of this brief review we will discuss the most common targets for gene therapy in brain tumors. In the second part, we will review the evolution of adenoviruses as gene vehicles. In addition, we will examine the role of recombinant mutant oncolytic adenoviruses as anticancer tools. From the results to date it is clear that gene therapy strategies for brain tumors are quite promising but more critical research is required, mainly in the vector field, if the strategies are to achieve their true potential in ameliorating patients with gliomas.

Development and application of a minimal-adenoviral vector system for gene therapy of hemophilia A

To achieve efficient delivery and sustained expression of the human factor VIII cDNA in vivo, a minimal-adenoviral (mini-Ad) vector system was developed. The system is composed of a mini-Ad vector with essential cis-elements (less than 1 kb) of the viral genome, an E1-deleted ancillary Ad with packaging attenuation, and an E1-complementing production cell line. Based on this system, MiniAdFVIII was generated to deliver a 27 kb expression cassette consisting of a full-length human factor VIII cDNA flanked by human albumin promoter and genomic sequences. The MiniAdFVIII vector mediated expression of functional human factor VIII in HepG2 and 293 cells. A single-dose intravenous injection of 10(11) viral particles in hemophilic mice of MiniAdFVIII produced a sustained high-level expression of human factor VIII (at 100-800 ng/ml up to 369 days) which corrected the FVIII-deficient phenotype. Safety studies of MiniAdFVIII showed that there were no significant toxic effects in mice and dogs after single intravessel doses of up to 3 x 10(11) and 6 x 10(12) viral particles, respectively. Studies for developing the MiniAdFVIII vector with a site-specific integration mechanism and progress in the development of a human factor VIII-tolerized mouse model for pre-clinical studies of MiniAdFVIII are reported. Further pre-clinical studies and product development of MiniAdFVIII for clinical trials are also discussed.

Peritoneal response to a septic challenge. Comparison between open laparotomy, pneumoperitoneum laparoscopy, and wall lift laparoscopy

BACKGROUND

Laparoscopic surgery has a lower incidence of surgical infection than open surgery. Differential factors that may modify the bacterial biology and explain this finding to some extent include CO(2) atmosphere, less desiccation of intraabdominal structures, fewer temperature changes, and a better preserved peritoneal and systemic immune response. Previous data suggest that the immune response and acute phase response are better preserved after laparoscopy. Therefore, we designed a study to evaluate the early peritoneal response to sepsis in an experimental peritonitis model comparing open surgery with CO(2) and abdominal wall lift laparoscopy.

METHODS

The study subjects comprised 360 mice distributed into the following four groups: group 1, n = 72 (controls); group 2, n = 96 (open surgery), 2-3 cm laparotomy, with abdominal cavity exposed to the air for 30 min; group 3, n = 96, CO(2) laparoscopy (5 mmHg pneumoperitoneum) for 30 min; group 4, n = 96, wall lift laparoscopy for 30 min. Intraabdominal contamination in the four groups was induced with 1 ml of E. coli suspension (1 x 10(4) CFU/ml) 10 min before abdomen closure. Peritoneal fluid and blood samples were obtained 1.5, 3, 24, and 72 h after surgery, and TNF, IL-1, and IL-6 were measured (via ELISA), as well as quantitative culture.

RESULTS

The number of CFU (colony-forming units) obtained in peritoneal fluid and positive blood culture rates were significantly lower in the laparoscopic groups than in the open group. IL-1 peritoneal levels were significantly lower after 24 h and 72 h in the laparoscopy groups. IL-6 levels decreased sharply in the laparoscopy groups at 24 h and 72 h. There were no differences between the two types of laparoscopy models (CO(2) and wall lift).

CONCLUSIONS

Peritoneal response to sepsis is better preserved after laparoscopy than after open surgery. CO(2) does not seem to influence bacterial growth. According to these findings, laparoscopy entails less local trauma and better preserved intraabdominal conditions.

Effect of spleen size on splenectomy outcome. A comparison of open and laparoscopic surgery

BACKGROUND

Laparoscopic splenectomy (LS) is gaining acceptance as an alternative to open splenectomy (OS). However, splenomegaly presents an obstacle to LS, and massive splenomegaly has been considered a contraindication. Analyses comparing the procedure with the open approach are lacking. The purpose of this study was to analyze the effect of spleen size on operative and immediate clinical outcome in a series of 105 LS compared with a series of 81 cases surgically treated by an open approach.

METHODS

Between January 1990 and November 1998, 186 patients underwent a splenectomy for a wide range of splenic disorders. Of these patients, 105 were treated by laparoscopy (group I, LS; data prospectively recorded) and 81 were treated by an open approach (group II, OS analyzed retrospectively). Patients also were classified into three groups according to spleen weight: group A, <400 g; group B, 400-1000 g; and group C, >1000 g. Age, gender, operative time, perioperative transfusion, spleen weight, conversion rate, mode of spleen retrieval (bag or accessory incision), postoperative analgesia, length of stay, and morbidity were recorded in both main groups.

RESULTS

Operative time was significantly longer for LS than for OS. However, LS morbidity, mortality, and postoperative stay were all lower at similar spleen weights. Spleens weighing more than 3,200 g required conversion to open surgery in all cases. When LS outcome for hematologic malignant diagnosis was compared with LS outcome for a benign diagnosis, malignancy did not increase conversion rate, morbidity, and transfusion, even though malignant spleens were larger and accessory incisions were required more frequently. Postoperative hospital stay was significantly longer in malignant than in benign diagnosis (5 +/- 2.4 days vs. 4 +/- 2.3 days; p < 0. 05).

CONCLUSIONS

In patients with enlarged spleens, LS is feasible and followed by lower morbidity, transfusion rate, and shorter hospital stay than when the open approach is used. For the treatment of this subset of patients, who usually present with more severe hematologic diseases related to greater morbidity, LS presents potential advantages.

[Laparoscopic splenectomy as an alternative to open surgery in the treatment of autoimmune thrombocytopenia]

BACKGROUND

Several studies have shown the potential advantages laparoscopic splenectomy (LS) over open surgery. The aim of this study has been to evaluate the advantages of LS over open surgery in the treatment of autoimmune thrombocytopenia.

PATIENTS AND METHODS

54 consecutive patients splenectomized for the treatment of idiopathic thrombocytopenic purpura (ITP) or HIV-related thrombocytopenia were analyzed. Operative features (operative time, conversion to open surgery, accessory spleens), immediate (stay, analgesia and blood transfusion requirements) and late postoperative features (platelet count), as well as splenectomy-related complications in both surgical procedures were compared.

RESULTS

Between February 1990 and February 1997, 54 splenctomies were performed for the treatment of autoimmune thrombocytopenia (ITP, n = 47, and HIV-related thrombocytopenia, n = 7). Eighteen were performed through an open approach, and 36 by laparoscopy. Both groups were comparable with regard to age, sex, platelet count, disease duration and body mass index. LS was completed in 34 cases (conversion to open surgery: 5.5%). The incidence of accessory spleens was 11% in the LS group and 5.5% in the open surgery group. Postoperative morbidity (16% vs 28%) and blood requirements (25% vs 33%) were lower after LS, but the differences did not reach statistical significance. Analgesia requirements (7 [SD 3] vs 11 [6]; p < 0.01) and postoperative stay (3.8 [2.6] vs 7.4 [3] days; p < 0.01) were significantly shorter after LS. Following splenectomy, the platelet counts became normal in 72% of patients submitted to LS and 78% of patients in the open surgery group. After 20 and 63 months mean follow-up, one patient in each group developed late complications.

CONCLUSION

As compared to open surgery, LS offers a better immediate clinical outcome, with similar long-term results.

The hypersensitive response. A programmed cell death associated with plant resistance

In plants, the hypersensitive response (HR) is defined as a rapid cell death occurring in response to pathogen attack, and is closely related to active resistance. Initiation of the HR process begins with the recognition of the pathogen by the plant, which is mediated mainly by the pathogen avirulence genes and the plant resistance genes. Then, complex signal transduction pathways intervene, involving changes in protein phosphorylation, production of reactive oxygen species and modification of ion fluxes. Components required for the regulation of the HR cell death are now being identified genetically by the isolation of mutants, in contrast to those involved in the execution of the cell death programme, which are still largely unknown. Further genetic and biochemical analyses will undoubtedly answer the question as to whether this form of programmed cell death (PCD) can be compared with other forms of PCD in plants and with apoptosis in animals.

Splenomegaly should not be considered a contraindication for laparoscopic splenectomy

OBJECTIVE

To analyze the impact of spleen size on operative and immediate clinical outcome in a series of 74 laparoscopic splenectomies (LS).

SUMMARY BACKGROUND DATA

LS is gaining acceptance as an alternative to open splenectomy. However, splenomegaly hinders LS, and massive splenomegaly has been considered a contraindication.

METHODS

Between February 1993 and September 1997, 74 patients with a wide range of splenic disorders were treated by laparoscopy and prospectively recorded. They were classified into three groups according to spleen weight: group I, <400 g (n = 52); group II, 400 to 1000 g (n = 9); and group III, >1000 g (n = 13). Age, operative time, number of trocars required, need for perioperative transfusion, spleen weight, conversion rate, mode of spleen retrieval (bag or accessory incision), postoperative analgesia requirements, length of hospital stay, and morbidity rates were recorded.

RESULTS

LS was completed in 69 patients, and the conversion rate was thus 6.7%. Operative time was significantly longer in patients with larger spleens, and an accessory incision was more frequently required. However, there were no significant differences in transfusion rate, length of stay, severe morbidity, or conversion rate.

CONCLUSIONS

Preliminary evaluation of LS for patients with large spleens suggests that it requires a longer operative time, but it is feasible and may potentially offer the same advantages (shorter stay and faster recovery) as it does to those with smaller spleens.

How, when, and why bile duct injury occurs. A comparison between open and laparoscopic cholecystectomy

BACKGROUND

Bile duct injury (BDI) is a severe complication of laparoscopic cholecystectomy (LC). There is general agreement about the increase of this complication after LC vs open cholecystectomy (OC), but comparative studies are scarce. The aim of this paper has been to compare the incidence and clinical features of BDI after LC vs open procedures.

MATERIALS AND METHODS

3,051 OC, performed from June 1977 to December 1988 were retrospectively analyzed and compared with 1,630 LCs performed from June 91 to August 96, for which data were prospectively recorded. Age, sex, type of BDI, performance of intraoperative cholangiography (IOC), underlying biliary pathology, morbidity, mortality, and late morbidity were all analyzed.

RESULTS

BDI incidence was higher in group II (LC) (N: 16, 0.95%) than in group I, (OC, N: 19. 0.6%). BDI incidence was also higher in the group of patients in which it was necessary to convert to an open procedure (3/109, 2.7%, p < 0.05). BDIs were more frequently diagnosed intraoperatively in group I (OC, 18/19) than in group II (LC, 12/16). In both groups, BDI was more prevalent in cases operated by staff surgeons than residents, mainly in complicated gallbladder patients, with a bile duct of less than 7-mm diameter. Morbidity, postoperative stay, mortality, and late morbidity were similar after a BDI in both types of approach.

CONCLUSIONS

(1) BDI increases with LC. (2) BDI after LC carries a similar postoperative morbidity and mortality to those after OC. (3) Incidence of BDI in converted cases increases significantly and this constitutes a high-risk group.

Extraperitoneal laparoscopically assisted ilioinguinal lymphadenectomy for treatment of malignant melanoma

BACKGROUND

Current treatment of malignant melanoma of the leg includes ilioinguinal lymphadenectomy (IIL). Standard open IIL (open IIL) includes sectioning of the inguinal ligament to gain access to the iliac nodes. Extraperitoneal laparoscopic IIL (lap IIL) is a feasible, less aggressive approach. It can be combined with standard superficial lymphadenectomy for treatment of malignant melanoma.

DESIGN

Comparative, prospective, nonrandomized series.

SETTING

Tertiary care center.

PATIENTS

Twelve consecutive, unselected patients with malignant melanoma treated with lap IIL (group 1) were compared with 10 consecutive, unselected patients with malignant melanoma on whom open IIL was performed (group 2).

INTERVENTIONS

Standard open IIL and laparoscopic extraperitoneal iliac lymphadenectomy (lap IIL) plus superficial groin lymphadenectomy.

MAIN OUTCOME MEASURES

Operative time, intraoperative complications, requirements of analgesia, total volume of lymphatic drainage, number of lymph nodes retrieved, immediate morbidity, hospital stay, and long-term morbidity were evaluated.

RESULTS

Operative time was significantly longer for the lap IIL group (group 1) than for the open IIL group (group 2) (177+/-44 vs 140+/-18 minutes, respectively; P<.05), but no patients in group 1 needed conversion to open surgery or developed related complications. Overall lymphatic drainage was significantly lower in group 1 than in group 2 (615+/-518 mL vs 1393+/-793 mL, repectively; P<.01). The number of doses of analgesics (13+/-8 vs 31+/-22, P<.03) and length of postoperative stay (7.3+/-3.3 vs 13+/-5 days, P<.006) were also significantly lower in the laparoscopic group. The overall number of lymph nodes retrieved was similar in both groups (10.2+/-4.6 vs 10+/-3, P=.9). One patient developed a groin hernia of 6 m after open IIL.

CONCLUSIONS

Laparoscopically assisted IIL offers a less aggressive approach than open IIL and entails less pain and a shorter hospital stay, as we observed in 2 groups with similar oncological results (mainly, a similar number of lymph nodes retrieved) who were treated with one procedure or the other. Further research should be done to confirm these preliminary advantages in a prospective randomized trial with long-term follow-up.

Laparoscopic surgery for splenic disorders. Lessons learned from a series of 64 cases

Laparoscopic splenectomy (LS) has recently been gaining acceptance as an alternative to open splenectomy. However, several aspects, such as learning curve, residual splenic function, and management of large spleens, remain controversial. In this paper we present the analysis of technical details and immediate and late outcome of a consecutive series of 64 cases of splenic disorders approached by laparoscopy. Between Feb-1993 and April-1997, 64 patients with a wide range of splenic disorders were treated by laparoscopy, and prospectively recorded. Age, body mass index, operative time, number of trocars, perioperative transfusion, spleen weight, conversion rate, mode of spleen retrieval (bag or accessory incision), postoperative analgesia, stay and morbidity were analyzed. Late failures after LS were reevaluated with 99mTc-heat-damaged red blood cells scintigraphy and CT. LS was performed in 61 patients, and two cases with splenic cyst and one splenic artery aneurysm received a laparoscopic partial cystectomy and aneurysmectomy. LS was performed through an anterior approach in 12 patients and laterally in 49. Conversion rate was 6.5%. Accessory spleens were found in 7 patients (7/61, 11.5%). Morbidity was 16%. There was no correlation between the weight of the spleen, platelet count or obesity with operative time. A lateral approach was associated with a decrease in operative time (p < 0.002), postoperative stay (p < 0.001), transfusion (p < 0.04) and number of trocars (p < 0.001). Operative time was significantly longer in large spleens (> 1000 gr) (p < 0.001). However, there were no differences in transfusion rate, stay, morbidity or conversion rate. After a follow up of 12 m, 10 patients revealed a low platelet count. Scintigraphy showed residual splenic tissue in 3 (ITP). A wide range of splenic disorders can be treated by laparoscopy, including enlarged spleens. This technique should be continually audited, but initial results reflect the approach's safety and advantages provided that great technical care is taken and an exhaustive search for accessory spleens is conducted.

Cancer dissemination during laparoscopic surgery: tubes, gas, and cells

Port-site metastasis has been an unexpected finding after laparoscopic surgery in gastrointestinal cancer patients. No clear explanation exists for this phenomenom. The aims of this study were to evaluate the dissemination pattern in an experimental model of hepatocarcinoma in the rat and summarize current knowledge about the risks and the results of experimental studies on cancer dissemination during laparoscopic surgery. NDA-induced hepatocarcinoma was obtained in Sprague-Dawley rats. Tumors were manipulated during laparoscopy (group 1, n = 11) or laparotomy (group 2, n = 12). A Medline review of all experimental studies about the risk of cancer dissemination during laparoscopic surgery was undertaken. Both models were associated with implants in parietal wounds [1/11 in group 1 (9%) vs. 1/12 in group 2 (8%), p = NS]. Analysis of the current literature confirms that laparoscopy is associated with abdominal cell mobilization, and cells can be recovered in trocars, filtered exhaust gas, and instruments. Postoperative immunosuppression, the biologic aggressiveness of the tumor, and the gas used for laparoscopy also influence tumoral growth. Port-site metastases are secondary to multiple factors, including the technical skill of the surgeon, the biologic properties of the tumors, and local environmental aspects. Undoubtedly, laparoscopy can help disseminate aggressive tumors and should be reserved for diagnostic and staging procedures or for treatment of low-grade malignant tumors. Therapeutic resection, especially of colon cancer, should be restricted to prospective and randomized trials until there are enough hard data to rule out the clinical importance of this potentially severe complication.

Residual splenic function after laparoscopic splenectomy: a clinical concern

OBJECTIVE

To document the existence of residual splenic function after laparoscopic splenectomy in a series of 48 patients.

DESIGN

A noncomparative descriptive case series.

SETTING

A tertiary care center.

PATIENTS

A series of 9 patients without clinical improvement after laparoscopic splenectomy of 48 consecutive patients undergoing laparoscopic splenectomy for several hematologic disorders after a mean follow-up of 16 months (range, 1-40 months).

INTERVENTIONS

A computed tomographic scan and technetium Tc 99m sodium pertechnetate heat-damaged red blood cell scintigraphy were performed for patients with partial (platelet count <100x10(9)/L) or total (platelet count <50x10(9)/L) failure of improvement.

MAIN OUTCOME MEASURE

Evidence of residual splenic tissue by image diagnosis.

RESULTS

The condition of 9 of the 48 patients failed to improve after laparoscopic splenectomy. Six patients experienced a total failure of improvement and 3 experienced a partial failure of improvement (1 patient had human immunodeficiency virus-related thrombocytopenia and 8 had idiopathic thrombocytopenic purpura). Three patients had residual splenic function, which was revealed by scintigraphy. The results of a computed tomographic scan showed an accessory spleen in one patient and splenic implants in splenic fossa in another patient.

CONCLUSION

Laparoscopic splenectomy has a promising role in the management of hematologic diseases requiring splenectomy, but it requires exquisite care to avoid parenchymal rupture and cell spillage and to avoid leaving accessory spleens, which can lead to the failure of surgical treatment.