Increased tumor growth and spread after laparoscopy vs laparotomy: influence of tumor manipulation in a rat model

Minimally invasive radical hysterectomy and the importance of avoiding cancer cell spillage for early-stage cervical cancer: a narrative review

Radical hysterectomy is a standard surgery to treat early-stage uterine cervical cancer. The Laparoscopic Approach to Cervical Cancer (LACC) trial has shown that patients receiving minimally invasive radical hysterectomy have a poorer prognosis than those receiving open radical hysterectomy; however, the reason for this remains unclear. The LACC trial had 2 concerns: the learning curve and the procedural effects. Appropriate management of the learning curve effect, including surgeons' skills, is required to correctly interpret the result of surgical randomized controlled trials. Whether the LACC trial managed the learning curve effect remains controversial, based on the surgeons' inclusion criteria and the distribution of institutions with recurrent cases. An appropriate surgical procedure is also needed, and avoiding intraoperative cancer cell spillage plays an important role during cancer surgery. Cancer cell spillage during minimally invasive surgery to treat cervical cancer is caused by several factors, including 1) exposure of tumor, 2) the use of a uterine manipulator, and 3) direct handling of the uterine cervix. Unfortunately, these issues were not addressed by the LACC trial. We evaluated the results of minimally invasive radical hysterectomy while avoiding cancer cell spillage for early-stage cervical cancer. Our findings show that avoiding cancer cell spillage during minimally invasive radical hysterectomy may ensure an equivalent oncologic outcome, comparable to that of open radical hysterectomy. Therefore, evaluating the importance of avoiding cancer cell spillage during minimally invasive surgery with a better control of the learning curve and procedural effects is needed.

Long-Term Outcomes of Laparoscopic Distal Gastrectomy for Locally Advanced Gastric Cancer: The KLASS-02-RCT Randomized Clinical Trial

PURPOSE

It is unclear whether laparoscopic distal gastrectomy for locally advanced gastric cancer is oncologically equivalent to open distal gastrectomy. The noninferiority of laparoscopic subtotal gastrectomy with D2 lymphadenectomy for locally advanced gastric cancer compared with open surgery in terms of 3-year relapse-free survival rate was evaluated.

PATIENTS AND METHODS

A phase III, open-label, randomized controlled trial was conducted for patients with histologically proven locally advanced gastric adenocarcinoma suitable for distal subtotal gastrectomy. The primary end point was the 3-year relapse-free survival rate; the upper limit of the hazard ratio (HR) for noninferiority was 1.43 between the laparoscopic and open distal gastrectomy groups.

RESULTS

From November 2011 to April 2015, 1,050 patients were randomly assigned to laparoscopy (n = 524) or open surgery (n = 526). After exclusions, 492 patients underwent laparoscopic surgery and 482 underwent open surgery and were included in the analysis. The laparoscopy group, compared with the open surgery group, suffered fewer early complications (15.7% v 23.4%, respectively; P = .0027) and late complications (4.7% v 9.5%, respectively; P = .0038), particularly intestinal obstruction (2.0% v 4.4%, respectively; P = .0447). The 3-year relapse-free survival rate was 80.3% (95% CI, 76.0% to 85.0%) for the laparoscopy group and 81.3% (95% CI, 77.0% to 85.0%; log-rank P = .726) for the open group. Cox regression analysis after stratification by the surgeon revealed an HR of 1.035 (95% CI, 0.762 to 1.406; log-rank P = .827; P for noninferiority = .039). When stratified by pathologic stage, the HR was 1.020 (95% CI, 0.751 to 1.385; log-rank P = .900; P for noninferiority = .030).

CONCLUSION

Laparoscopic distal gastrectomy with D2 lymphadenectomy was comparable to open surgery in terms of relapse-free survival for patients with locally advanced gastric cancer. Laparoscopic distal gastrectomy with D2 lymphadenectomy could be a potential standard treatment option for locally advanced gastric cancer.

Long-term Oncologic Outcomes of Laparoscopic Anterior Resections for Cancer with Natural Orifice Versus Conventional Specimen Extraction: A Case-Control Study

BACKGROUND

Although the short-term advantages of natural orifice specimen extraction are widely recognized, controversy exists concerning oncologic safety after laparoscopic surgery for colorectal cancer.

OBJECTIVE

This study aimed to investigate the impact of natural orifice specimen extraction on local recurrence and long-term survival of patients undergoing colorectal cancer surgery.

DESIGN

This is a propensity score-matched comparative study.

SETTING

This study presents a single-center experience.

PATIENTS

We retrospectively analyzed the records of patients who underwent curative laparoscopic anterior resection for American Joint Committee on Cancer stage I to III sigmoid or upper rectal cancer in 2011 to 2014, based on prospectively collected data.

INTERVENTIONS

Oncologic outcomes were compared between patients undergoing natural orifice or conventional specimen extraction by minilaparotomy. Patients were matched 1:1 according to propensity scores calculated by logistic regression analysis with the following covariates: American Joint Committee on Cancer stage, tumor diameter, age, sex, BMI, and T stage. Cox proportional hazards regression analysis was performed to determine the impact on oncologic outcome.

MAIN OUTCOME MEASURES

The primary outcomes measured were local recurrence and disease-free survival rates at 5 years.

RESULTS

Of 392 eligible patients, 188 were matched (94 undergoing natural orifice specimen extraction and 94 undergoing conventional extraction by minilaparotomy). Median follow-up was 50.3 months. The cumulative local recurrence risk at 5 years was 2.3% and 3.5% (p = 0.632), whereas 5-year disease-free survival for all tumor stages combined was 87.3% and 82.0% (p = 0.383) in laparoscopic anterior resection with natural orifice specimen extraction and conventional extraction groups. T3 and T4 stages were the only variables independently associated with disease-free survival.

LIMITATIONS

This study was limited because it focused on a single center, was a retrospective analysis, contained no long-term anorectal function testing, and had a small sample size.

CONCLUSION

Long-term oncologic outcomes of patients undergoing laparoscopic anterior resection with natural orifice specimen extraction for sigmoid and upper rectal cancer do not differ from those undergoing conventional extraction. Thus, natural orifice specimen extraction could be a viable alternative to reduce abdominal wall insult in laparoscopic colorectal operations for malignancy in selected patients. See Video Abstract at http://links.lww.com/DCR/B241. RESULTADOS ONCOLÓGICOS A LARGO PLAZO DE RESECCIONES ANTERIORES LAPAROSCÓPICAS PARA CÁNCER A TRAVÉS DE ORIFICIO NATURAL FRENTE A EXTRACCIÓN CONVENCIONAL DEL ESPÉCIMEN: UN ESTUDIO DE CASOS Y CONTROLES: Si bien las ventajas a corto plazo de la extracción de especímenes por orificio natural son ampliamente reconocidas, existe controversia con respecto a la seguridad oncológica después de la cirugía laparoscópica para el cáncer colorrectal.Investigar el impacto de la extracción de especímenes por orificio natural en la recurrencia local y la supervivencia a largo plazo de pacientes sometidos a cirugía de cáncer colorrectal.Estudio comparativo con emparejamiento por puntuación de propensión.Experiencia en un centro único.Analizamos retrospectivamente los registros de pacientes que se sometieron a resección anterior laparoscópica curativa para cáncer sigmoideo o rectal superior AJCC en estadio I-III en 2011-2014, con base en datos recolectados prospectivamente.Los resultados oncológicos se compararon entre pacientes sometidos a extracción por orificio natural o convencional mediante minilaparotomía de especímenes. Los pacientes fueron emparejados 1:1 de acuerdo con los puntajes de propensión calculados por análisis de regresión logística con las siguientes covariables: estadio AJCC, diámetro del tumor, edad, sexo, índice de masa corporal y estadio T. Se realizó un análisis de regresión de riesgos proporcionales de Cox para determinar el impacto en el resultado oncológico.Recurrencia local y tasas de supervivencia libre de enfermedad a los 5 años.De 392 pacientes elegibles, 188 fueron emparejados (94 sometidos a extracción de espécimen por orificio natural y 94 a extracción convencional por minilaparotomía). La mediana de seguimiento fue de 50.3 meses. El riesgo cumulativo de recurrencia local a 5 años fue de 2.3% y 3.5% (p = 0.632), mientras que la supervivencia libre de enfermedad a 5 años para todas las etapas tumorales combinadas fue de 87.3% y 82.0% (p = 0.383) en los grupos de resección anterior laparoscópica con extracción de espécimen por orificio natural y extracción convencional, respectivamente. Las etapas T3 y T4 fueron las únicas variables asociadas independientemente con la supervivencia libre de enfermedad.Centro único, análisis retrospectivo, ausencia de pruebas de función anorrectal a largo plazo y tamaño de muestra pequeño.Los resultados oncológicos a largo plazo de los pacientes sometidos a resección anterior laparoscópica con extracción de espécimen por orificio natural para cáncer sigmoideo y rectal superior no difieren de los de aquellos sometidos a extracción convencional. Por lo tanto, la extracción de especímenes por orificio natural podría ser una alternativa viable para reducir el insulto a la pared abdominal en operaciones colorrectales laparoscópicas por malignidad en pacientes selectos. Consulte Video Resumen en http://links.lww.com/DCR/B241.

Spillage of bacterial products during colon surgery increases the risk of liver metastases development in a rat colon carcinoma model

Surgical resection of the primary tumor provides the best chance of cure for patients with colorectal carcinoma (CRC). However, bacterial translocation during intestinal surgery has been correlated with poor long-term oncological outcome. Therefore, we investigated the influence of bacterial contamination during colon surgery on CRC liver metastases development. Blood and liver samples of patients undergoing resection of primary CRC or liver metastases were collected. Cell numbers, activation markers and inflammatory mediators were determined. Tumor cell adhesion and outgrowth after sham- or colectomy operations were determined in a rat model, in which tumor cells had been injected into the portal vein.

White blood cells and granulocytes were increased in per- and post-operative patient blood samples. IL-6 was also increased post-operatively compared to the preoperative level. Expression of NOX-2, NOX-4 and polymorphonuclear cells (PMNs) numbers were elevated in post-operative human liver samples. In vitro stimulation of macrophages with plasma of rats after colectomy resulted in production of reactive oxygen species (ROS). Colectomy in rats increased D-lactate levels in plasma, supporting bacterial translocation. Decreased expression of tight junction molecules and increased tumor cell adhesion and outgrowth was observed. Treatment with a selective decontamination of the digestive tract (SDD) cocktail decreased tumor cell adherence after colectomy.

In conclusion, postoperative bacterial translocation may activate liver macrophages and PMNs, resulting in ROS production. As we previously showed that ROS release led to liver vasculature damage, circulating tumor cells may adhere to exposed extracellular matrix and grow out into liver metastases. This knowledge is pivotal for development of therapeutic strategies to prevent surgery-induced liver metastases development.

Potential impact of invasive surgical procedures on primary tumor growth and metastasis

Surgical procedures such as tumor resection and biopsy are still the gold standard for diagnosis and (determination of) treatment of solid tumors, and are prognostically beneficial for patients. However, growing evidence suggests that even a minor surgical trauma can influence several (patho) physiological processes that might promote postoperative metastatic spread and tumor recurrence. Local effects include tumor seeding and a wound healing response that can promote tumor cell migration, proliferation, differentiation, extracellular matrix remodeling, angiogenesis and extravasation. In addition, local and systemic immunosuppression impairs antitumor immunity and contributes to tumor cell survival. Surgical manipulation of the tumor can result in cancer cell release into the circulation, thus increasing the chance of tumor cell dissemination. To prevent these undesired effects of surgical interventions, therapeutic strategies targeting immune response exacerbation or alteration have been proposed. This review summarizes the current literature regarding these local, systemic and secondary site effects of surgical interventions on tumor progression and dissemination, and discusses studies that aimed to identify potential therapeutic approaches to prevent these effects in order to further increase the clinical benefit from surgical procedures.

Inhibition of peritoneal dissemination of colon cancer by hyperthermic CO2 insufflation: A novel approach to prevent intraperitoneal tumor spread

BACKGROUND

The increasing use of laparoscopic surgery for advanced gastrointestinal cancer raises concerns about intra-peritoneal tumor spread. Prevention of peritoneal dissemination is extremely important but a preventive modality is lacking. The aim of this study was to examine a novel approach (hyperthermic CO2 insufflation, HT-CO2) for preventing peritoneal dissemination during laparoscopic surgery.

METHODS

A peritoneal dissemination model was established in Balb/c nu/nu mice by intraperitoneal injection of human colon cancer cells (SW1116, 1×106). The mice (n = 48) were subsequently randomized into two groups and subjected to hyperthermic CO2 (43°C, >95% humidity, HT-CO2 group) or standard normothermic CO2 (21°C, <1% relative humidity, NT-CO2 group) insufflation for 3 hours. The mice were sacrificed 28 days later. The peritoneal dissemination was quantitatively analyzed by counting and weighing the peritoneal nodules. The port sites and ascites volume were measured. The peritoneal damage of HT-CO2 was histologically examined with light microscopy and scanning electron microscopy. Intra-abdominal adhesions were evaluated 4 weeks later.

RESULTS

The number of peritoneal nodules in the HT-CO2 group was significantly less than that in the NT-CO2 group (10.21±3.72 vs. 67.12±5.49, P<0.01). The mean weight of metastatic tumors in the HT-CO2 group was significantly lower than that in the NT-CO2 group (0.31±0.10g vs. 2.16±0.31g, P<0.01). Massive ascites were found in the NT-CO2 group while significantly less ascites developed in HT-CO2- treated mice (8.26±0.31ml vs. 1.27±0.28ml, P<0.01). No port-site metastases were detected in the HT-CO2 group while the incidence of the NT-CO2 group was 12.5% (3/24). HT-CO2 subjection resulted in slight peritoneal damage; the peritoneum returned to normal within five days. No adhesions formed after HT-CO2 treatment.

CONCLUSIONS

HT-CO2 can suppress peritoneal dissemination of colon cancer cells and only causes slight and transient peritoneal damage. HT-CO2 may serve as a promising adjuvant treatment for preventing peritoneal dissemination in laparoscopic resection of advanced colorectal cancer.

Survival variability of controls and definition of imaging endpoints for longitudinal follow-up of pancreatic ductal adenocarcinoma in rats

BACKGROUND

The 3Rs guideline is the gold standard for ethics in animal experimentation. Two of those rules, namely refinement and reduction, require further improvement. The objective of this study was to define pathways to better compliance with these prerequisites. Two methods which move us in this direction are: (1) using small animal imaging techniques for pancreatic ductal adenocarcinoma (PDAC) follow-up and (2) reduction of the number of control animals included in a study of PDAC progression under treatment.

MATERIALS AND METHODS

Firstly, we used MicroCT scan to diagnose events showing PDAC progression prior to any clinical symptoms to thereby define more humane endpoints identifiable before any painful phenomenon is observed. Secondly, in order to test the hypothesis of using a reference control group in all preclinical studies of a new treatment of PDAC, we investigated the stability of the results obtained with the control groups in three successive identical studies comparing placebo and gemcitabine in tumor-bearing Lewis rats.

RESULTS

Two imaging endpoints were found. The first was the observation of a liver metastasis assessing PDAC diffusion and, earlier than liver metastasis, the presence of bands of fluid along the flanks, with more or less a medial displacement of bowel and solid viscera, reflecting a peritoneal ascites. Results of the longitudinal follow-up of rats in the gemcitabine study revealed heterogeneity in the survival rate in the three control groups, as opposed to the survival rate in the three treated groups which did not differ statistically. As a result, the significance of improved survival with chemotherapy varied greatly according to the control group used for the comparison, ranging from no impact to a highly significant effect.

CONCLUSION

The early detection by the means of animal imaging of one or more signs indicating the onset of a critical step in the development of the disease (e.g., ascites or/and metastasis) allows the researcher to prevent the occurrence of animal pain, thereby ensuring better animal welfare. However, using a single standard control group in an effort to use fewer animals for a given model runs such a significant risk of false results that it mars the entire study. Although reducing the number of animals in a study remains the gold standard of our experimental practice, in this case it would come at the price of a loss of validity of the results.

Does carbon dioxide pneumoperitoneum enhance wound metastases following laparoscopic abdominal tumor surgery? A meta-analysis of 20 randomized control studies

The mechanisms involved in the development of wound metastasis following laparoscopic abdominal tumor surgery remain unclear. The aim of this study was to accurately assess whether the duration of carbon dioxide pneumoperitoneum (CDP) during laparoscopic abdominal tumor surgery enhances wound metastases. We conducted a systematic review of PubMed, Cochrane Library, and Embase through December 2013 to identify animal experiments comparing wound recurrence between laparoscopic and gasless laparoscopic procedures or open procedures. The outcome of interest was the number of animals with a wound tumor. Meta-regression was used to assess whether heterogeneity was explained by study level covariates (animal model, study size, CDP pressure, duration, and evaluated time). Twenty randomized control studies involving 1,229 animals were included. Wound recurrence was not significant in the laparoscopic surgery (LP) vs. gasless laparoscopic surgery (GLP) subgroups [odds ratio (OR), 2.23; 95 % confidence interval (CI), 0.90-5.55; P = 0.08) or the LP vs. laparotomy (LA) subgroups (OR, 0.97; 95 % CI, 0.31-3.00; P = 0.08). Overall postoperative wound recurrence results were not significantly different between the study groups and controls (OR, 1.47; 95 % CI, 0.74-2.92; P = 0.28). A meta-regression analysis showed that the outcome was not correlated with the covariates (animal model: P = 0.82; evaluated time: P = 0.30; pressure of CDP: P = 0.12; duration time: P = 0.80). Current evidence suggests that CDP does not enhance wound metastases following laparoscopic abdominal tumor surgery. Additional large sample, well-designed, randomized, controlled trials are needed to further confirm whether CDP duration in laparoscopic abdominal tumor surgery significantly enhances wound recurrence.

Pancreatoduodenectomy associated complications influence cancer recurrence and time interval to death

BACKGROUND

Resection is the only life-prolonging option for pancreatic or periampullary cancer. Cell-mediated immunity might reduce progression of metastasis or local recurrence likelihood, but surgery associated morbidity can suppress this immunity. The aim of this study was to examine the influence of complications on cancer specific survival after pancreatoduodenectomy (PD) for pancreatic and periampullary cancer.

METHOD

517 consecutive patients who underwent PD for pancreatic or periampullary adenocarcinoma were analysed.

RESULTS

After median follow-up of 24 (14-44) months, 377 (73%) patients had died from progressive disease, 140 (27%) were alive. Median survival for pancreatic adenocarcinoma was 22 (18-25) months following an uncomplicated postoperative course versus 16 (13-19) months for patients with major surgical complications (p = 0.021). Multivariable Cox regression analysis demonstrated that microscopically residual disease (R1), complications, and adjuvant therapy were independent factors for recurrence. Within the R1 group, survival for patients with complications was even more limited, 9.7 (8.3-11.0) versus 18.7 (15.0-22.5) for those without (p < 0.001). For patients with R1 resection complications was the only independent predictor for a shorter time interval to death (hazard ratio 1.96; 95% CI 1.16-3.30). Complications did not influence survival of patients with periampullary adenocarcinoma.

CONCLUSION

Complications after resection are independently related to an impaired survival following PD for pancreatic, but not periampullary cancer. The effect is even more dramatic in patients who had an R1 resection. Although the relation is not causal per se, the findings support the hypothesis of a complication-induced, compromised immunity rendering patients more susceptible for recurrent disease.

Myo-inositol trispyrophosphate-mediated hypoxia reversion controls pancreatic cancer in rodents and enhances gemcitabine efficacy

Hypoxia and dysfunctional tumor vessels represent a prominent feature of pancreatic cancer, being, at least in part, responsible for chemotherapy resistance and immune suppression in these tumors. We tested whether the increase of oxygen delivery induced in vivo by myo-inositol trispyrophosphate (ITPP) can reverse hypoxia, control tumor growth and improve chemotherapy response. Tumor size, metastatic development (microcomputed tomography scan follow-up) and the survival of rats and nude or NOD.SCID mice, (bearing syngenic rat and MiaPaCa2- or patient-derived pancreatic tumors), were determined on ITPP and/or gemcitabine treatment. Partial oxygen pressure, expression of angiogenic factors and tumor histology were evaluated. Infiltration and oxidative status of immune cells, as well as chemotherapy penetration in tumors, were determined by fluorescence-activated cell sorting, fluorometry, nitric oxide release assays, Western blot and confocal microscopy. Weekly intravenous ITPP application resulted in the inhibition of metastasis development and restricted primary tumor growth, showing a superior effect on the rats' survival compared with gemcitabine. ITPP treatment restored tumor normoxia and caused a reduction in hypoxia inducible factor-1α levels, with subsequent VEGF and Lox downregulation, resulting in improved vessel structure and decreased desmoplasia. The latter effects translated into elevated immune cells influx and improved susceptibility to gemcitabine treatment. Growth of human pancreatic tumor xenografts was strongly inhibited by administration of ITPP. ITPP exploits a two-stage mechanism causing rapid, early and sustainable late stage normoxia. This is due to the angiogenic factor modulation and vascular normalization, leading to enhanced chemotherapy delivery and synergistic life prolongation, on combination with low doses of gemcitabine.

Polypoid Gallbladder Lesion in the Context of Renal Cell Carcinoma: Is Laparoscopic Cholecystectomy a Reasonable Option?

Introduction. The only curative therapeutic approach for renal cell carcinoma (RCC) is surgery. Laparoscopic surgery for RCC has become an established surgical procedure with equivalent cancer-free survival rate, following the same surgical oncological principles as open surgery. Metastatic RCC of the gallbladder is a rare phenomenon. Hence, there are few reports regarding their management. Case Presentation. We report 2 cases of gallbladder metastasis from clear cell RCC treated by laparoscopic cholecystectomy. The first case was that of a 44-year-old male patient who underwent palliative cholecystectomy, the second case was that of an 83-year-old female patient who is doing well 55 months after surgery without evidence of disease recurrence. Conclusion. The outcome allows us to demonstrate the interest of surgical resection of RCC metastases in the gallbladder by laparoscopic cholecystectomy, respecting surgical oncological principles. Laparoscopic resection of an uncommon gallbladder metastasis can provide long-term favorable outcome.

Small bowel exploration and resection using single-port surgery: a safe and feasible approach

AIM

The aim of this study is to demonstrate the efficacy of wireless capsule endoscopy for preoperative identification of bleeding sources and/or small bowel tumours in surgical patients and to evaluate the feasibility of single-port surgery in the treatment of such pathologies.

METHOD

Five patients presenting with obscure gastrointestinal bleeding or/and mild small bowel obstruction were investigated to diagnose and localize the bleeding source or tumour using capsule endoscopy imaging, and, if necessary, with other investigative modalities. All patients were operated on using single-port surgery for small bowel exploration, lesion confirmation, small bowel resection and anastomosis.

RESULTS

Small bowel pathology was successfully detected by video capsule endoscopy in three of four patients, and was further substantiated by contrast CT, double-balloon endoscopy or enteroclysis. Complete small bowel exploration, intra-operative identification and oncological resection of the involved segment and anastomosis (intracorporeal and extracorporeal) was successfully performed in all five patients using single-port access without any complication, morbidity or mortality.

CONCLUSION

This study demonstrates the feasibility and safety of single-port small bowel resection performed after a high-quality preoperative localization of the tumour.

Incidence of port-site metastasis after undergoing robotic surgery for biliary malignancies

AIM: To investigate the incidence of clinically detected port-site metastasis (PSM) in patients who underwent robotic surgery for biliary malignancies.

METHODS: Using a prospective database, the patients undergoing fully robotic surgery for biliary malignancies between January 2009 and January 2011 were included. Records of patients with confirmed malignancy were reviewed for clinicopathological data and information about PSM.

RESULTS: Sixty-four patients with biliary tract cancers underwent robotic surgery, and sixty patients met the inclusion criteria. The median age was 67 year (range: 40-85 year). During a median 15-mo follow-up period, two female patients were detected solitary PSM after robotic surgery. The incidence of PSM was 3.3%. Patient 1 underwent robotic anatomatic left hemihepatectomy and extraction of biliary tumor thrombi for an Klatskin tumor. She had a subcutaneous mass located at the right lateral abdominal wall near a trocar scar. Patient 2 underwent robotic pancreaticoduodenectomy for distal biliary cancer. She had two metachronous subcutaneous mass situated at the right lateral abdominal wall under a same trocar scar at 7 and 26 mo. The pathology of the excised PSM masses confirmed metastatic biliary adenocarcinoma.

CONCLUSION: The incidence of PSMs after robotic surgery for biliary malignancies is relatively low, and biliary cancer can be an indication of robotic surgery.

Port-site metastasis after laparoscopic surgery for urological malignancy: forgotten or missed

Purpose. Port-site metastasis has been a concern with the common use of laparoscopy in urologic oncology. We conducted this study to provide a review of port-site metastases reported after the laparoscopy in managing urologic malignancies, possible contributing factors and preventative measures. Materials and Methods. An electronic search of MEDLINE using the combined MESH key words “port-site metastasis” and “Urology”. Results. 51 articles addressing port-site metastasis after laparoscopic surgery for urolo¬gical malignancy were identified. Conclusion. Port-site metastasis after laparoscopic surgery for urolo¬gical malignancy is rare. The incidence is comparable to the rate for surgical wound metastases.

Comparative evaluation of surgical stress of laparoscopically assisted vaginal radical hysterectomy and lymphadenectomy and laparotomy for early-stage cervical cancer

The aim of this study was to objectively evaluate the benefits of laparoscopically assisted vaginal radical hysterectomy and lymphadenectomy for early-stage cervical cancer. Clinical data were prospectively collected from patients with IA-IIB cervical cancer who underwent laparoscopically assisted vaginal radical hysterectomy (n1=33) and laparotomy (n2=30). Peripheral blood samples were obtained prior to surgery and at 1 and 2 h into the operation, as well as on days 1, 4 and 7 following surgery to measure serum interleukin-6, C-reaction protein and cortisol. Results showed that there was no conversion to laparotomy in the laparoscopy group. The average blood loss was 317.23±217.20 ml (laparoscopy group) and 872.58±693.16 ml (laparotomy group). No significant difference was found in the number of resected pelvic lymph nodes (19.74±7.43 in the laparoscopy group and 20.35±6.62 in the laparotomy group). At days 1 and 7 after surgery, the serum IL-6 level was significantly different in the laparoscopy and laparotomy groups (day 1: laparoscopy group 17.14±16.53 pg/ml and laparotomy group 34.32±20.97 pg/ml, p=0.001; day 7: laparoscopy group 6.7±7.21 pg/ml and laparotomy group 17.54±16.47 pg/ml, p=0.001). The serum CRP level was significantly different at days 1 and 7 after the operation (day 1: laparoscopy group 7024.72±949.12 ng/ml and laparotomy group 7586.61±869.42 ng/ml, p=0.018; day 7: laparoscopy group 4357.71±2108.85 ng/ml and laparotomy group 6967.96±995.02 ng/ml, p<0.001). A significant difference was noted in the serum cortisol level at day 4 after the operation (122.29±65.17 ng/ml in the laparoscopy group and 186.76±68.61 ng/ml in the laparotomy group, p<0.001). In conclusion, the differences in clinical data and the various parameters pertinent to surgical stress evaluated in this study suggest that laparoscopic surgery for cervical cancer causes less postoperative stress than conventional open surgery.

A novel lifting system for minimally accessed surgery: a prospective comparison between "Laparo-V" gasless and CO2 pneumoperitoneum laparoscopic colorectal surgery

PURPOSE

Carbon dioxide (CO(2)) pneumoperitoneum can lead to cardiopulmonary loading and complications. By comparing with conventional CO(2) pneumoperitoneum approach, we introduce a novel Laparo-V lifting system for gasless laparoscopic colorectal surgery.

METHODS

In a prospective study, patients with colonic lesions underwent either Laparo-V gasless (n = 20) or conventional CO(2) pneumoperitoneum (n = 19) laparoscopic colectomy. Twenty patients who underwent open surgery were enrolled as control. Intra-operative monitoring includes blood pressures, heart rate, O(2) saturation, and end-tidal CO(2) (ET-CO(2)). Serum level of interleukin 6 (IL-6), C-reactive protein (CRP), cortisol, and lymphocyte subpopulations (CD4/CD8) were measured repeatedly. Postoperative recovery was indicated by return of bowel function and postoperative hospital stay.

RESULTS

Patient characteristics were not different between the three groups. There were three conversions in each laparoscopy group, making conversion rates 15% and 15.7% for Laparo-V and CO(2) pneumoperitoneum groups, respectively. Vital signs remained stable in Laparo-V and open surgery groups; while, elevated ET-CO(2) and heart rate were noted in CO(2) pneumoperitoneum group. Both laparoscopy groups had a significant faster recovery and shorter hospital stay than the open surgery group. Postoperative elevation of IL-6, CRP, and cortisol level was observed in all the three groups, of note, the change was most significant in the open surgery group.

CONCLUSIONS

Laparo-V gasless laparoscopic approach is feasible in various colorectal procedures. It carries advantages comparable with those of CO(2) pneumoperitoneum; while, the intra-operative hemodynamic was more stable. Therefore, laparoscopic approach using the Laparo-V system could be beneficial to patients with high cardiopulmonary risk and represents an alternative for minimally invasive surgery.

Systemic and peritoneal inflammatory response after laparoscopic-assisted gastrectomy and the effect of inflammatory cytokines on adhesion of gastric cancer cells to peritoneal mesothelial cells

INTRODUCTION

There still remain concerns over the potential for peritoneal metastasis after laparoscopic surgery. We designed this trial to investigate the effects of the inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) on the interaction between gastric cancer cells and mesothelial cells, and to evaluate differences in both the peritoneal and systemic cytokine (IL-1β and TNF-α) concentrations after laparoscopic and conventional surgical approaches, thus offering another possible advantage of laparoscopic procedures for treatment of gastric cancer.

EXPERIMENTAL DESIGN

A reproducible human in vitro assay was developed to study adhesion of SGC-7901 and MKN-45 human gastric cancer cells to monolayers of primary cultured human peritoneal mesothelial cells (HPMCs). Tumor cell adhesion to a mesothelial monolayer was assessed after preincubation of the monolayer with IL-1β and TNF-α using flow cytometry. Expression of adhesion molecules (ICAM-1, VCAM-1, and CD44) and their counterparts (LFA-1 and VLA-4) was investigated by real-time polymerase chain reaction (PCR) immunocytochemical staining. Furthermore, the proinflammatory cytokines IL-1β and TNF-α were measured perioperatively in peritoneal drain fluid and in serum by enzyme immunoassay.

RESULTS

Preincubation of the mesothelial monolayer with IL-1β and TNF-α resulted in enhanced tumor cell adhesion of SGC-7901 and MKN-45 cells. Mesothelial cells showed significant enhancement of expression of ICAM-1, VCAM-1, and CD44 after stimulation with IL-1β and TNF-α. Meanwhile their counterparts (LFA-1, VLA-4, and CD44) were identified in gastric cancer cells. The level of IL-1β in peritoneal drain fluid and in serum perioperatively in the laparoscopy-assisted gastrectomy group was lower than in the conventional open gastrectomy group, whereas there were no significant differences between the laparoscopic-assisted distal gastrectomy (LADG) and conventional open distal gastrectomy(CODG) groups with respect to TNF-α.

CONCLUSIONS

The presented results prove that IL-1β and TNF-α are significant stimulating factors in gastric cancer cell adhesion in vitro and may therefore partly account for local tumor recurrence and peritoneal metastasis in vivo. Owing to less impact on the postoperative abdominal regional and systemic immune responses, laparoscopic surgery not only shows clinically relevant advantages but also causes less effect of inflammatory factors on local recurrence and peritoneal metastasis of gastric cancer than conventional operations. Thus, we offer another possible advantage of laparoscopic procedures for treatment of gastric cancer.

Feasibility and reliability of pancreatic cancer staging using fiberoptic confocal fluorescence microscopy in rats

BACKGROUND & AIMS

Surgical management of pancreatic cancer depends on tumor resectability and staging. This study evaluated a new in vivo technique, fiberoptic confocal fluorescence microscopy (FCFM), for detection and staging of pancreatic tumors in rats.

METHODS

FCFM was used with a protease-activated fluorescent marker (ProSense; VisEn Medical Inc, Woburn, MA) for in vivo imaging of solid organs (1.8-microm resolution) in a rat model of pancreatic ductal adenocarcinoma. A preliminary study described the FCFM rendering of normal and pathologic tissues. Subsequently, 2 double-blind studies compared FCFM to standard histology in (1) detection of tumors in rat models of cancer and controls and (2) detection of nodal involvement (splenic, celiac, mesenteric, and colic) 4, 5, and 6 weeks after tumor induction vs controls.

RESULTS

Tumor cells displayed a fluorescent ductal pattern compared with non-fluorescent normal pancreas or normal follicular pattern of lymph nodes (LNs). FCFM detected all the pancreatic tumors (1.7-mm mean diameter) and identified 23 LNs that contained metastases of 99 LNs examined. Standard histologic analyses resulted in 1 false-negative result in tumor detection and 2 false negatives in LN detection, whereas FCFM produced no false-negative results. Additional serial sectioning confirmed all tumors and 16 metastatic LNs; FCFM had a negative predictive value of 100% and a positive predictive value of 69.6%.

CONCLUSIONS

Real-time "virtual biopsy" using FCFM detects tumors and LN metastases with 100% sensitivity and 92.2% specificity in rats, making it a reliable technique for detection and staging of pancreatic cancer.

Improvement of gemcitabine-based therapy of pancreatic carcinoma by means of oncolytic parvovirus H-1PV

Pancreatic carcinoma is a gastrointestinal malignancy with poor prognosis. Treatment with gemcitabine, the most potent chemotherapeutic against this cancer up to date, is not curative, and resistance may appear. Complementary treatment with an oncolytic virus, such as the rat parvovirus H-1PV, which is infectious but nonpathogenic in humans, emerges as an innovative option.

PURPOSE

To prove that combining gemcitabine and H-1PV in a model of pancreatic carcinoma may reduce the dosage of the toxic drug and/or improve the overall anticancer effect.

EXPERIMENTAL DESIGN

Pancreatic tumors were implanted orthotopically in Lewis rats or subcutaneously in nude mice and treated with gemcitabine, H-1PV, or both according to different regimens. Tumor size was monitored by micro-computed tomography, whereas bone marrow, liver, and kidney functions were monitored by measuring clinically relevant markers. Human pancreatic cell lines and gemcitabine-resistant derivatives were tested in vitro for sensitivity to H-1PV infection with or without gemcitabine.

RESULTS

In vitro studies proved that combining gemcitabine with H-1PV resulted in synergistic cytotoxic effects and achieved an up to 15-fold reduction in the 50% effective concentration of the drug, with drug-resistant cells remaining sensitive to virus killing. Toxicologic screening showed that H-1PV had an excellent safety profile when applied alone or in combination with gemcitabine. The benefits of applying H-1PV as a second-line treatment after gemcitabine included reduction of tumor growth, prolonged survival of the animals, and absence of metastases on CT-scans.

CONCLUSION

In addition to their potential use as monotherapy for pancreatic cancer, parvoviruses can be best combined with gemcitabine in a two-step protocol.

The perioperative period is an underutilized window of therapeutic opportunity in patients with colorectal cancer

OBJECTIVE

In this review, we address the underlying mechanisms by which surgery augments metastases outgrowth and how these insights can be used to develop perioperative therapeutic strategies for prevention of tumor recurrence.

SUMMARY BACKGROUND DATA

Surgical removal of the primary tumor provides the best chance of long-term disease-free survival for patients with colorectal cancer (CRC). Unfortunately, a significant part of CRC patients will develop metastases, even after successful resection of the primary tumor. Paradoxically, it is now becoming clear that surgery itself contributes to development of both local recurrences and distant metastases.

METHODS

Data for this review were identified by searches of PubMed and references from relevant articles using the search terms "surgery," "CRC," and "metastases."

RESULTS

Surgical trauma and concomitant wound-healing processes induce local and systemic changes, including impairment of tissue integrity and production of inflammatory mediators and angiogenic factors. This can lead to immune suppression and enhanced growth or adhesion of tumor cells, all of which increase the chance of exfoliated tumor cells developing into secondary malignancies.

CONCLUSIONS

Because surgery remains the appropriate and necessary means of treatment for most CRC patients, new adjuvant therapeutic strategies that prevent tumor recurrence after surgery need to be explored since the perioperative therapeutic window of opportunity offers promising means of improving patient outcome but is unfortunately underutilized.

Impact of the surgical peritoneal environment on pre-implanted tumors on a molecular level: a syngeneic mouse model

BACKGROUND

We recently demonstrated that a CO(2) pneumoperitoneum at either a high or low IPP has few if any short term effects on peritoneal dissemination when tumors are well established before surgery. The objective of the present study was to evaluate the impact of the surgical peritoneal environment on pre-implanted tumors on a molecular level.

MATERIALS AND METHODS

On day 7, C57BJ6 mice received an intraperitoneal inoculation of a mouse ovarian cancer cell line (ID8). On day 0, mice were randomized into four groups: anesthesia alone, CO(2) pneumoperitoneum at a low (2 mm Hg) or high (8 mm Hg) IPP, or laparotomy. Groups were further subdivided into four groups and a laparotomy was performed to collect pre-implanted tumors on POD 1, 2, 7, or 14. Expression levels of beta-1 integrin, cMet, uPA, uPAR, and PAI-1 mRNA in pre-implanted nodules were measured using real-time PCR.

RESULTS

Expression levels of uPA, uPAR, and cMet mRNA were significantly higher in the laparotomy group than in the control group on POD 1. We detected significantly higher expression levels of uPAR and cMet in the laparotomy group than in the control group on PODs 2 and 7. There were no significant differences in the expression levels of any genes examined among the low IPP, anesthesia alone, and control groups on POD 1, 2, 7, or 14.

CONCLUSION

The impact of a CO(2) pneumoperitoneum at a low IPP on gene expression levels of pre-implanted tumors might be minimal until POD 14 in the present mouse model.

Uterine Leiomyosarcoma: Does the Primary Surgical Procedure Matter?

Background:

Uterine leiomyosarcoma (LMS) has a poor prognosis even after early-stage diagnosis. Because there are no accurate diagnostic tools for preoperatively distinguishing LMS from uterine leiomyoma, surgeons might opt for partial surgical procedures such as myomectomy or subtotal hysterectomy. We sought to determine whether a surgical procedure that cuts through the tumor influences prognosis.

Materials and Methods:

Demographic and clinical data of consecutive patients with stage I LMS treated between 1969 and 2005 were reviewed. The study population was divided into group A: patients whose first surgical intervention was total hysterectomy (n = 21); and group B: patients who underwent procedures involving tumor injury, for example, myomectomy, laparoscopic hysterectomy with a morcellator knife, or hysteroscopic myomectomy (n = 16). Survival rates were analyzed and compared. A Cox proportional hazards model was used to assess the association between variables of interest and prognosis.

Results:

The median age at diagnosis was 50 years (range, 30-74 years). Median follow-up duration was 44 months. The 2 groups did not differ significantly in age at diagnosis, menopausal status, gravidity, parity, postoperative radiotherapy, or time to last follow-up. Kaplan-Meier curves showed significantly better survival rates (P = 0.04) and a significant advantage in recurrence rate (P = 0.03) for group A compared with group B. Survival in group A was 2.8-fold better than that in group B (95% confidence interval, 1.02-7.67). These estimates remained stable after adjustment for age, menopausal status, and radiotherapy.

Conclusions:

In patients with stage I LMS, primary surgery involving tumor injury seems to be associated with a worse prognosis than total hysterectomy as a primary intervention.

Blocking alpha2 integrins on rat CC531s colon carcinoma cells prevents operation-induced augmentation of liver metastases outgrowth

Currently, an operation is the only curative option for patients with colorectal cancer. Unfortunately, many patients will develop liver metastases even after successful resection of the primary tumor. Removal of primary colorectal carcinoma may paradoxically increase the risk of metastases development, because accumulating evidence suggests that surgical trauma can stimulate tumor growth. In the present study, we investigated the effects of abdominal trauma on liver metastases development. Surgical trauma dramatically increased adhesion of tumor cells in the liver, leading to enhanced outgrowth of metastases. Endothelial stress was observed rapidly after an operation, suggesting that abdominal trauma resulted in impairment of blood vessel integrity. Tumor cells preferentially adhered to extracellular matrix (ECM). Furthermore, preincubation of tumor cells with anti-alpha2 integrin antibodies completely reverted operation-induced augmentation of CC531s adhesion and liver metastases outgrowth. As such, we postulate that blood vessel integrity in the liver is compromised after abdominal trauma, resulting in enhanced ECM exposure, which enables tumor cell adhesion and metastases outgrowth.

CONCLUSION

Perioperative treatments that either aim to reduce endothelial stress or block the interaction between tumor cells and ECM represent promising new therapeutic strategies for the prevention of liver metastases development after resection of the primary tumor.

Perioperative desmopressin prolongs survival in surgically treated bitches with mammary gland tumours: a pilot study

Desmopressin (1-deamino-8-d-arginine vasopressin, also known as DDAVP) is a safe haemostatic compound capable of inhibiting lymph node and lung metastasis in a mouse model of mammary tumour manipulation and surgical excision. The aim of this study was to test the efficacy and safety of perioperative DDAVP (1microg/kg) in surgically treated bitches with mammary gland tumours (MGT). Twenty-one, otherwise healthy, intact bitches, with malignant MGT stage III or IV were randomly allocated to DDAVP (n=11) or placebo (n=10) groups. En bloc mastectomy of the affected gland/s was performed. DDAVP had a significant beneficial effect on disease-free period (P<0.01) and overall survival time (P<0.05). No side effects were seen in any of the cases. Whatever the mechanism of action, it seems that DDAVP may have a novel use in cancer surgery to minimise spread or survival of residual malignant cells. Additional, large scale controlled trials are required to fully evaluate this adjuvant pharmacological protocol.

Preclinical models of regional lymph node tumor metastasis

Animal models have produced vital information regarding the mechanisms of RLN metastasis. Modern imaging and molecular techniques have made it clear that growing tumors secrete cytokines that induce invasion, angiogenesis, lymphangiogenesis, increased intratumoral IFV and IFP, increased fluid flow from the tumor to the surrounding tissues, increased lymphatic flow, an increase in the rate of entry of tumor cells into lymphatic capillaries, and an increased number of tumor cells reaching the RLN(s). This is important knowledge that will help direct translational research in human patients. We can look forward to continued improvement in the management of human tumors that metastasize to the RLNs.

Inhibition of ovarian cancer growth and implantation by paclitaxel after laparoscopic surgery in a mouse model

OBJECTIVE

We used an established experimental model to evaluate the influence of intraperitoneal chemotherapy on the generation of laparoscopy-associated metastases and the effectiveness of chemotherapy.

STUDY DESIGN

Twenty-four nude mice underwent laparoscopy with carbon dioxide insufflation and the instillation of a tumor cell suspension with or without paclitaxel into the peritoneal cavity. Mice were allocated to 1 of the following groups (8 mice to each group): (1) controls; (2) paclitaxel given during the operation; (3) paclitaxel given after the operation. Mice were killed 30 days after the procedure, and the peritoneal cavity and port sites were examined for the presence of tumors.

RESULTS

Tumor implantation and port-site metastases were reduced more by the intraoperative intraperitoneal administration of paclitaxel during the operation than by administration after the operation.

CONCLUSION

Intraoperative intraperitoneal administration of paclitaxel may decrease significantly the occurrence of port-site metastasis and intraperitoneal dissemination in an animal study.

Impact of taurolidin and octreotide on liver metastasis and lipid peroxidation after laparoscopy in chemical induced ductal pancreatic cancer

BACKGROUND

There is controversial discussion whether metastasis initiated by laparoscopy with carbon dioxide might be prevented by instillation of taurolidin or radical scavengers like the somatostatin analogue Octreotide. Therefore we evaluated the effects of laparoscopic lavage with taurolidin and Octreotide on liver metastasis after staging laparoscopy in ductal pancreatic cancer.

METHODS

In 60 Syrian hamsters pancreatic adenocarcinoma was induced by weekly subcutanous injection of 10 mg N-nitrosobis-2-oxopropylamin/kg body weight for 10 weeks. In the 16th week laparoscopic staging biopsy by use of carbon dioxide was performed. Finally animals underwent abdominal irrigation with saline (gr.1, n = 20), taurolidin (0.5%) (gr.2, n = 20) or Octreotide (gr.3, n = 20). In week 25 animals were sacrificed, pancreas and liver were analysed.

RESULTS

Size of pancreatic carcinomas was decreased in the taurolidin gr. compared to the other two groups. Furthermore the number of liver metastasis per animal was reduced after lavage with taurolidin (2 +/- 2) and Octreotide (2.5 +/- 2) compared to saline irrigation (4 +/- 4) (p < 0.05). Additionally the incidence of port site metastases was significantly reduced in the taurolidin group. Activity of antioxidative enzyme superoxide dismutase (SOD) was increased while concentration of products of lipidperoxidation was decreased in non-metastatic liver after taurolidin irrigation compared to saline or Octreotide irrigation.

CONCLUSIONS

Taurolidin irrigation during laparoscopy might be a new concept to reduce the number of liver metastasis and port site metastases in pancreatic cancer.

Laparoscopy and Malignancy

BACKGROUND

The advantages of pneumoperitoneum-based surgery are well documented. Laparoscopy is the gold standard of treatment in certain benign conditions such as cholelithiasis and gastroesophageal disease. This success has led to the application of laparoscopy in the management algorithm of malignant conditions. There is currently no universally accepted consensus of the role of pneumoperitoneum-based surgery in the treatment of cancer. This is due to the early reports of port site metastasis, initial lack of randomized controlled trials and the concern of performing oncologically adequate operations. The aim of this section is to review the current literature and attempt to obtain a consensus of the role of laparoscopy in the treatment of cancer.

MATERIALS AND METHODS

A literature search was conducted through Pubmed with key words laparoscopy, pneumoperitoneum, carbon dioxide, malignancy, cancer, and port site metastasis. The obtained results were divided into various sections such as non-randomized reports, randomized reports, animal studies, human studies, etc. A comparison was made between laparoscopic and open resections when possible.

RESULTS

There are several published reports of studies in animal models and in humans relating to pneumoperitoneum-based surgery in the setting of malignancy. There are also a few randomized controlled trials that compared open versus laparoscopic surgery for malignancies of various organ systems. In addition, the early reports of alarmingly high rate of port site metastasis have been scaled down to rates comparable to wound recurrences after open resections.

SUMMARY

Laparoscopy has added another dimension to the management of patients with cancer. Advanced training, superior instrumentation, and a better understanding of the pathophysiology of carbon dioxide pneumoperitoneum has led to the successful application of laparoscopy. The improved results are obtained in centers with high volume of patients and with experience in both fields of oncology and minimally invasive surgery. Laparoscopy is now an integral tool in the management algorithm of malignancies of some organ systems and its role will be further expanded in the future.

Increased peritoneal dissemination after laparotomy versus pneumoperitoneum in a mouse cecal cancer model

BACKGROUND

The effect of carbon dioxide (CO(2)) pneumoperitoneum on the liberation of cancer cells from the primary tumor is not clear. This study investigated the influence of laparotomy versus CO(2) pneumoperitoneum on the progression of colon cancer with serosal invasion in a mouse model.

METHODS

Pieces of human colon adenocarcinoma (HT29) tumor were implanted in the cecal wall of 45 BALB/c nude mice. Each mouse underwent one of three procedures: laparotomy, CO(2) pneumoperitoneum, or anesthesia (control). Three weeks later, the size and weight of cecal tumors, the number of nodules, and the tumor volume score of peritoneal dissemination were examined. Another 45 mice were treated in the same way. The cecal tumor was resected on days 1, 3, or 5 after treatment. Total RNA was isolated from the resected tumors. The expression of E-cadherin and beta-1 integrin messenger RNA (mRNA) was examined by semiquantitative real-time reverse transcriptase-polymerase chain reaction assay.

RESULTS

Significantly more nodules of peritoneal dissemination were found in the laparotomy group than in the control group (p < 0.05). The tumor volume score of peritoneal dissemination in the laparotomy group was significantly higher than in the other two groups (p < 0.05). The expression of E-cadherin mRNA at day 5 in the laparotomy group was significantly less than in the other two groups (p < 0.05). There were no differences in beta-1 integrin among three groups.

CONCLUSIONS

Peritoneal dissemination was more extensive after laparotomy than after CO(2) pneumoperitoneum in a mouse model of cecal cancer with serosal invasion. Decreased expression of E-cadherin mRNA in tumors after laparotomy, but not after CO(2) pneumoperitoneum, may be associated with the increase in peritoneal dissemination.

Port site metastases

BACKGROUND

Concerns about port site metastases have limited the application of minimally invasive surgery for intra-abdominal malignancies. The purpose of this review article was to summarize the current literature regarding port site metastases.

METHODS

A Medline search identified >100 articles in English published during the last 15 years regarding the history, incidence, etiology, and prevention of port site metastases. These articles were reviewed and are summarized.

RESULTS

The incidence of port site metastases, initially thought to be as high as 21%, is now thought to be closer to the incidence of wound metastases after open surgery. Multiple etiologic factors have been studied including direct wound contamination, surgical technique, effects of carbon dioxide pneumoperitoneum, and changes in host immune response. Various preventive measures have been proposed.

CONCLUSIONS

Port site metastases are a well-documented and devastating complication after laparoscopic resection of intra-abdominal malignancies. Although the etiology is not yet understood, a number of factors are contributory. All efforts should be made to prevent port site metastases.

Potential prophylactic measures against postoperative immunosuppression: could they reduce recurrence rates in oncological patients?

BACKGROUND

Removing the primary tumor is indispensable for eliminating the major pool of metastasizing cells, but the surgical procedure itself is suspected of promoting metastases. This adverse effect is attributed to several mechanisms acting in synergy, including mechanical release of tumor cells, enhanced angiogenesis, secretion of growth factors, and immunosuppression. Here we provide new insights into mechanisms of postoperative immunosuppression and assess the assumptions underlying the hypothesis that, by suppressing cell-mediated immunity (CMI), surgery may render the patient vulnerable to metastases that otherwise could have been controlled.

METHODS

An extensive review of relevant articles in English identified by using the MEDLINE database and cross-referencing.

RESULTS

Current literature suggests that (1) CMI can control minimal residual disease, especially if surgery is performed early; (2) major surgery transiently but markedly suppresses CMI through multiple mechanisms now better understood; (3) surgical stress promotes experimental metastasis through immunosuppression, but the clinical evidence remains indirect because of ethical limitations.

CONCLUSIONS

Minimizing postoperative immunosuppression seems feasible, may limit recurrence, and should be introduced into the broader array of considerations when planning oncological surgeries. In the short run, physicians could try to avoid immunosuppressive anesthetic approaches, inadvertent hypothermia, excessive blood transfusions, and untended postoperative pain. When feasible, minimally invasive surgery should be considered. In the long run, clinical trials should evaluate prophylactic measures, including perioperative immunostimulation and several antagonists to cytokines and hormones specified herein.

Laparoscopic enhancement of tumour cell binding to the peritoneum is inhibited by anti-intercellular adhesion molecule-1 monoclonal antibody

BACKGROUND

There still remain some concerns over the phenomenon of port-site metastases (PSM) after laparoscopic surgery. The aim of this study was to investigate the effect of the pneumoperitoneum on tumor-mesothelial cell interactions.

METHODS

The adhesion of a colon carcinoma cell line to a mesothelial cell monolayer exposed to carbon dioxide, helium, or air was assessed using an in vitro adhesion assay. Changes in adherence were correlated with alterations in cell surface molecule expression by the mesothelial cells using flow cytometry after exposure to the different environments.

RESULTS

Exposure of the mesothelial cells to an in vitro pneumoperitoneum significantly enhanced tumor cell binding to the mesothelial cell monolayer. No differences in cell viability were observed between the groups. This was associated with increased expression of mesothelial intercellular adhesion molecule-1 (ICAM-1) mediated by nuclear factor kappa-B. The enhanced adhesion was abolished by ICAM-1 inhibition.

CONCLUSIONS

This study demonstrated that the laparoscopic environment increases the susceptibility of the mesothelium to tumor cell adherence, and this may be explained by changes in ICAM-1 expression.

Effects of taurolidine and octreotide on tumor growth and lipid peroxidation after staging-laparoscopy in ductal pancreatic cancer

Irrigation with taurolidine after laparoscopy decreases tumor growth in colon carcinoma. In pancreatic cancer subcutaneous therapy with octreotide decreases oxidative stress and carcinogenesis as well. However, it is still unclear, whether irrigation with taurolidine or octreotide after laparoscopic pancreatic biopsy reduces tumor growth in pancreatic cancer as well. In 60 Syrian hamsters ductal pancreatic adenocarcinoma was induced by weekly injection of 10mg/kg body weight N-nitrosobis-2-oxopropylamine s.c. for 10 weeks. In week 16 laparoscopic pancreatic biopsy by use of carbon dioxide was performed (gr. 1, n = 20) with subsequent laparoscopic irrigation with taurolidine (gr. 2, n = 20) or octreotide (gr. 3, n = 20). In week 25 hamsters were sacrificed. Our results show that macroscopic visible primary tumors were found in only one animal of the taurolidine group (5.9%), compared to 42.1% in the saline and 62.5% in the octreotide group (P<0.05). Carcinomas were smaller after saline (6+/-23 mm(2)) than after octreotide irrigation (70+/-120 mm(2), P<0.05). In conclusion this study showed that laparoscopic irrigation with taurolidine after pancreatic biopsy inhibited tumor growth in ductal pancreatic adenocarcinoma.

Tumor cell dissemination during laparoscopy: prevention and therapeutic opportunities

Port-site recurrences (PSRs) are abdominal wall recurrences that occur in the subcutaneous tissue within a trocar site after cancer laparoscopy and are not associated with peritoneal carcinomatosis. In order to develop PSRs, viable tumor cells must be liberated from the primary tumor, be transported to a wound, and find there a favorable environment for growth. The short clinical delay in the occurrence of PSRs and their size suggest massive cell seeding into the abdominal wall. Traumatic handling of the tumor, slipping of trocars, liquid projection, as well as poor extraction techniques can all cause implantation of malignant cells into the subcutaneous tissue. Such contact can also occur postoperatively if the trocar channels remain open. Some histologies (e.g. gallbladder adenocarcinoma), the presence of ascites and advanced tumor stage are risk factors for PSRs. Further conditions--including the use of gas--might also play a limited role. The first preventive measure is the correct indication for a laparoscopic approach. Several techniques have been demonstrated to prevent PSRs in the animal model: (a) fixation of trocars to the abdominal wall; (b) prevention of leakage; (c) careful specimen handling; (d) reducing trauma to the abdominal wall; (e) specimen isolation before extraction from the abdominal cavity; (f) trocar-site irrigation with a cytotoxic solution, and (g) closure of peritoneum. Further innovative therapies are currently under investigation. In the clinical setting, correct indication, surgical expertise and application of prophylactic measures seem to be the best way to prevent the occurrence of PSRs.

Laparoscopic total mesorectal excision: a consecutive series of 100 patients

OBJECTIVE

To analyze total mesorectal excision (TME) for rectal cancer by the laparoscopic approach during a prospective nonrandomized trial.

SUMMARY BACKGROUND DATA

Improved local control and survival rates in the treatment of rectal cancer have been reported after TME.

METHODS

The authors conducted a prospective consecutive series of 100 laparoscopic TMEs for low and mid-rectal tumors. All patients had a sphincter-saving procedure. Case selection, surgical technique, and clinical and oncologic results were reviewed.

RESULTS

The distal limit of rectal neoplasm was on average 6.1 (range 3-12) cm from the anal verge. The mean operative time was 250 (range 110-540) minutes. The conversion rate was 12%. Excluding the patient who stayed 104 days after a severe fistula and reoperation, the mean postoperative stay was 12.05 (range 5-53) days. The 30-day mortality was 2% and the overall postoperative morbidity was 36%, including 17 anastomotic leaks. Of 87 malignant cases, 70 (80.4%) had a minimum follow-up of 12 months, with a median follow-up of 45.7 (range 12-72) months. During this period 18.5% (13/70) died of cancer and 8.5% (6/70) are alive with metastatic disease. The port-site metastasis rate was 1.4% (1/70): a rectal cancer stage IV presented with a parietal recurrence at 17 months after surgery. The locoregional pelvic recurrence rate was 4.2% (3/70): three rectal cancers stage III at 19, 13, and 7 postoperative months.

CONCLUSIONS

Laparoscopic TME is a feasible but technically demanding procedure (12% conversion rate). This series confirms the safety of the procedure, while oncologic results are at present comparable to the open published series with the limitation of a short follow-up period. Further studies and possibly randomized series will be necessary to evaluate long-term clinical outcome in cancer patients.

The promotion of tumor metastasis by surgery and stress: immunological basis and implications for psychoneuroimmunology

This mini-review emphasizes a psychoneuroimmunology (PNI) perspective of the hypothesis that stress and surgical excision of the primary tumor can promote tumor metastasis. It first establishes the empirical and theoretical basis for control of metastasis by cell-mediated immunity (CMI), as well as the interactive role of non-immunological risk factors. It then describes the various aspects of surgery that suppress CMI, and the neuroendocrine mechanisms mediating suppression by stress and surgery. Last, it briefly reviews the empirical evidence, from animal and human studies, for the promotion of metastasis by stress and surgery, with specific reference to the mediating role of CMI. It is concluded that: (a) Immunological mechanisms most likely play a role in limiting metastasis in patients with solid tumors. (b) Immunosuppression can be deleterious, especially when surgery is conducted early, before the tumor develops insurmountable mechanisms to escape immune destruction. (c) The most sensitive period for the establishment of metastases is the immediate aftermath of surgery. Interventions aiming at reducing stress and immunosuppression should thus strive to start beforehand. (d) 'Psychological and physiological insults activate similar neuroendocrine mechanisms of immunosuppression. Therefore, a multimodal therapeutic approach should be used to prevent tumor metastasis during the perioperative period. (e) Studies employing interventions aimed at reducing the surgical stress response should preferably assess immunological indices with an established clinical relevance, and follow up long-term recurrence provided sample size assure statistical power. (f) The progress toward earlier detection of cancer, and our growing understanding of immunosuppression, continuously improves the chances for successful PNI interventions.

Desmopressin inhibits lung and lymph node metastasis in a mouse mammary carcinoma model of surgical manipulation

BACKGROUND AND OBJECTIVES

Desmopressin (DDAVP) is a synthetic derivative of vasopressin with hemostatic and fibrinolytic properties that has been used during surgery in patients with bleeding disorders. Our aim was to investigate the effect of DDAVP on lung and lymph node metastatic cell colonization using a preclinical mouse mammary carcinoma model of subcutaneous tumor manipulation and surgical excision.

METHODS

Female BALB/c mice bearing the highly aggressive F3II mammary carcinoma were subjected to repeated manipulations of primary tumors (0.5 kg/cm(2) during 2 min), followed (or not) by surgical excision. DDAVP was administered intravenously 30 min before and 24 h after each manipulation or surgery, at a dose of 2 microg/kg. At the end of the experiment, mice were sacrificed and necropsied.

RESULTS

Tumor manipulation induced dissemination to the axillary nodes and increased up to 6-fold the number of metastatic lung nodules. Perioperative treatment with DDAVP dramatically reduced regional metastasis. The incidence of lymph node involvement in manipulated animals was 12% with DDAVP and 87% without treatment (P < 0.02). Histopathological analysis of axillary nodes from DDAVP-treated animals showed sinusal histiocytosis and no evidence of cancer cells. Metastatic lung nodules were also reduced about 65% in animals treated with DDAVP (P = 0.026).

CONCLUSIONS

Our results suggest a potential clinical application of DDAVP in the management of breast cancer, as well as other aggressive solid tumors. DDAVP may be useful to reduce the risk of metastatic cell colonization both during and after surgical manipulation.