A model of port-site metastases of gallbladder cancer: The influence of peritoneal injury and its repair on abdominal wall metastases

Research progress on prognostic factors of gallbladder carcinoma

BACKGROUND

Gallbladder carcinoma is the most common malignant tumor of the biliary system, and has a poor overall prognosis. Poor prognosis in patients with gallbladder carcinoma is associated with the aggressive nature of the tumor, subtle clinical symptoms, ineffective adjuvant treatment, and lack of reliable biomarkers.

PURPOSE

Therefore, evaluating the prognostic factors of patients with gallbladder carcinoma can help improve diagnostic and treatment methods, allowing for tailored therapies that could benefit patient survival.

METHODS

This article systematically reviews the factors affecting the prognosis of gallbladder carcinoma, with the aim of evaluating prognostic risk in patients.

CONCLUSION

A comprehensive and in-depth understanding of prognostic indicators affecting patient survival is helpful for assessing patient survival risk and formulating personalized treatment plans.

The influences of a novel anti-adhesion device, thermally cross-linked gelatin film on peritoneal dissemination of tumor cells: The in vitro and in vivo experiments using murine carcinomatous peritonitis models

To create anti-adhesive materials to be more effective and safer, we developed a thermally cross-linked gelatin film that showed superior anti-adhesive effects with excellent peritoneal regeneration. However, it may act as a convenient scaffold for tumor cell growth, thereby accelerating peritoneal dissemination when used in surgery for abdominal tumors. In this study, we tried to clarify this issue using mouse carcinomatous peritonitis models. First, we examined the in vitro tumor cell growth of mouse B16 melanoma or Colon26 cells on the gelatin film or the conventional hyarulonate/carboxymethylcellulose film. Tumor cell growth on each film was significantly lower than that of the control (no film). Next, we conducted the following in vivo experiments: After the parietal peritoneum was partially removed and covered with each film or without any film, mice were inoculated intraperitoneally with B16 melanoma or Colon26/Nluc cells expressing NanoLuc luciferase gene. At 7 days after the operation, we measured the weight of B16 melanoma tumors or the NanoLuc activity of Colon26/Nluc cells using in vivo imaging at the injured sites. There were no significant differences in the weight of the tumors and the NanoLuc activity among the three groups. We also observed the survival time of mice receiving the same operation and treatments. There was no significant difference in the survival time among the three groups. These results suggest that the gelatin film will likely not accelerate peritoneal dissemination as a convenient scaffold for tumor cell growth when used in surgery for abdominal tumors. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2122-2130, 2018.

A case report of wound site seeding following cholecystectomy for dysplastic gallbladder

Wound site metastasis following cholecystectomy is an uncommon but well recognised complication following laparoscopic surgery for unsuspected gallbladder carcinoma. We describe a case of implantation of dysplastic cells with subsequent malignant transformation at the incision site 3 years post-cholecystectomy for an inflamed gallbladder. Histopathological examination of this tumour confirmed adenocarcinoma of pancreatobiliary origin, possibly secondary to gallbladder cells implantation and subsequent carcinomatous change. Unlike previously reported cases, the present case has two unique features: Firstly, the histology of the resected gallbladder at the initial operation was that of a low-grade dysplasia and not carcinoma; and secondly, there was a long interval between initial surgery and subsequent development of the wound site tumour. This case highlights that careful handling of the specimen tissue intraoperatively is paramount as cells implanted in the wound site can survive and undergo malignant transformation. All new masses occurring along the surgical wound site should be followed up and investigated to exclude implanted tumours.

Port-site metastasis as a primary complication following retroperitoneal laparoscopic radical resection of renal pelvis carcinoma or nephron-sparing surgery: A report of three cases and review of the literature

The present study reports the clinical data of two patients with renal pelvis carcinoma and one patient with renal carcinoma who developed port-site metastasis following retroperitoneal laparoscopic surgery. The current study aimed to identify the cause and prognosis of the occurrence of port-site metastasis subsequent to laparoscopic radical resection of renal pelvis carcinoma and nephron-sparing surgery. Post-operative pathology confirmed the presence of high-grade urothelial cell carcinoma in two patients and Fuhrman grade 3 renal clear cell carcinoma in one patient. Port-site metastasis was initially detected 1–7 months post-surgery. The two patients with renal pelvis carcinoma succumbed to the disease 2 and 4 months following the identification of the port-site metastasis, respectively, whereas the patient with renal carcinoma survived with no disease progression during the targeted therapy period. The occurrence of port-site metastasis may be attributed to systemic and local factors. Measures to reduce the development of this complication include strict compliance with the operating guidelines for tumor surgery, avoidance of air leakage at the port-site, complete removal of the specimen with an impermeable bag, irrigation of the laparoscopic instruments and incisional wound with povidone-iodine when necessary, and enhancement of the body's immunity. Close post-operative follow-up observation for signs of recurrence or metastasis is essential, and systemic chemotherapy may be required in patients with high-grade renal pelvis carcinoma and renal carcinoma in order to prolong life expectancy.

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.

Stimuli-induced organ-specific injury enhancement of organotropic metastasis in a spatiotemporal regulation

The relationship between inflammation and tumorigenesis has been established. Recently, inflammation is also reported to be a drive force for cancer metastasis. Further evidences show that various stimuli directly induced-injury in a specific organ can also promote metastasis in this organ, which include epidemiological reports, clinical series and experimental studies. Each type of cancer has preferential sites for metastasis, which is also due to inflammatory factors that are released by primary cancer to act on these sites and indirectly induce injuries on them. Host factors such as stress,fever can also influence distant metastasis in a specific site through stimulation of immune and inflammatory effects. The five aspects support an idea that specific-organ injury directly induced by various stimuli or indirectly induced by primary tumor or host factors activation of proinflammatory modulators can promote metastasis in this organ through a spatiotemporal regulation, which has important implications for personalized prediction, prevention and management of cancer metastasis.

Biological resonance for cancer metastasis, a new hypothesis based on comparisons between primary cancers and metastases

Many hypotheses have been proposed to try to explain cancer metastasis. However, they seem to be contradictory and have some limitations. Comparisons of primary tumors and matched metastases provide new insight into metastasis. The results show high concordances and minor differences at multiple scales from organic level to molecular level. The concordances reflect the commonality between primary cancer and metastasis, and also mean that metastatic cancer cells derived from primary cancer are quite conservative in distant sites. The differences reflect variation that cancer cells must acquire new traits to adapt to foreign milieu during the course of evolving into a new tumor in second organs. These comparisons also provided new information on understanding mechanism of vascular metastasis, organ-specific metastasis, and tumor dormancy. The collective results suggest a new hypothesis, biological resonance (bio-resonance) model. The hypothesis has two aspects. One is that primary cancer and matched metastasis have a common progenitor. The other is that both ancestors of primary cancer cells and metastatic cancer cells are under similar microenvironments and receive similar or same signals. When their interactions reach a status similar to primary cancer, metastasis will occur. Compared with previous hypotheses, the bio-resonance hypothesis seems to be more applicable for cancer metastasis to explain how, when and where metastasis occurs. Thus, it has important implications for individual prediction, prevention and treatment of cancer metastasis.

Camera-port site metastasis of a renal-cell carcinoma after robot-assisted partial nephrectomy

BACKGROUND AND PURPOSE

Port-site metastasis (PSM) is a rare complication of laparoscopic intervention in urologic malignancies. Of the greater than 50 reported cases of PSM in the urologic oncology literature, only 9 have occurred after surgery for renal-cell carcinoma (RCC). We report a 10th instance of RCC metastasis-in this case to the camera-port site after robot-assisted partial nephrectomy (RAPN). To our knowledge, this case is the first reported PSM of RCC after RAPN.

PATIENT AND METHODS

A 68-year-old man underwent an uncomplicated right RAPN for a 4-cm right renal mass (stage T1aN0M0). Five months later, he was found to have metastatic disease with an isolated peritoneal recurrence at the camera-port site. Biopsy of the lesion confirmed RCC, and the lesion was surgically resected. A comprehensive MEDLINE search for all published studies of port-site recurrences after laparoscopic renal surgery for RCC was performed.

RESULTS

Nine cases of PSM after successful laparoscopic radical or partial nephrectomy for locally confined RCC have been reported. Proposed etiologic factors for port-site recurrence include biologic aggressiveness of the tumor, patient immunosuppression, local wound factors, and technique-related factors. We report an unusual case of PSM to a camera port that was not used for specimen manipulation or extraction.

CONCLUSION

PSM after laparoscopic renal surgery for RCC is a rare occurrence. Our case, in which PSM occurred without specimen bag rupture or extraction through the port in question, highlights the importance of local and systemic factors in contributing to PSM occurrence. We also demonstrate that when PSM is the only site of disease recurrence, it can be successfully managed with minimally invasive surgical resection.

Laparoscopic versus open surgery for rectal cancer: a clinical comparative study

OBJECTIVE

To compare short-term surgical outcomes and long-term survival following laparoscopic or open resection for rectal cancer.

METHODS

A total of 381 patients undergoing laparoscopic surgery and 276 undergoing open surgery for curative resection of rectal cancer were included. Long-term survival and peri- and postoperative data were retrospectively reviewed from a prospectively-collected database.

RESULTS

Surgical groups were comparable regarding age, gender, tumour stage and preoperative comorbidities. Laparascopic surgery was associated with significantly longer duration of surgery, less intraoperative blood loss and fewer postoperative infections than open surgery. Patients who underwent laparoscopic resection had significantly earlier recovery of gastrointestinal function than those who underwent open surgery. There were no significant between-group differences in number of lymph nodes excised, specimen length or distal margin. The 3- and 5-year survival rates and overall survival were similar in the two groups, and survival was not influenced by tumour location.

CONCLUSION

Laparoscopic surgery can achieve the same oncological results as open resection in patients with rectal cancer, supporting its continued use in the management of this disease.

Evolving treatment strategies for gallbladder cancer

Gallbladder cancer is an uncommon cancer that has traditionally been associated with a poor prognosis. In the era of laparoscopic cholecystectomy, incidental gallbladder cancer has dramatically increased and now constitutes the major way patients present with gallbladder cancer. While patients with incidental gallbladder cancer have a better survival than patients with nonincidental gallbladder cancer, incidental gallbladder cancer can be associated with a varied prognosis. Imaging with computed tomography (CT), magnetic resonance imaging (MRI), and [18]F-fluorodeoxyglucose (FDG) positron emission tomography (PET), as well as diagnostic laparoscopy, all have varying roles in the workup of patients with incidental gallbladder cancer. For patients with T1b, T2, and T3 incidental gallbladder cancer re-resection is generally recommended. At re-exploration, many patients with incidental gallbladder cancer will have residual disease. Definitive oncologic management requires re-resection of the liver, portal lymphadenectomy, and attention to the common bile duct. The extent of the hepatic resection should be dictated by the ability to achieve a microscopically negative (R0) margin. Routine resection of the common bile duct is unnecessary but should be undertaken in the setting of a positive cystic duct margin. If an incidental gallbladder cancer is discovered at the time of surgery, whether the surgeon should directly proceed with a more definitive oncologic operation should depend on the surgeon's skill-set and experience. Gallbladder cancer has a propensity to recur. Although data for adjuvant therapy following resection are limited, some data do suggest a survival benefit for adjuvant chemoradiation therapy. Management of patients with gallbladder cancer requires a multidisciplinary approach with input from a surgeon skilled in hepatobiliary surgery.

Port-Site Recurrence After Laparoscopy-Assisted Gastrectomy: Report of the First Case

In advanced gastric cancer, laparoscopic management has been associated with trocar-site recurrence, even though laparoscopy-assisted gastrectomies have reported positive results to treat early-stage gastric cancer in the world. There are no reports of port-site recurrence after laparoscopic gastrectomy in the literature. In this paper, we present a case report of advanced gastric cancer with port-site recurrence 12 month after the initial operation. A wide excision of this recurrence was performed. Otherwise, the evaluation of metastasis in other sites remained negative at 18 months after the original operation. The laparoscopic surgeon should be aware of trocar-site recurrence when dealing with advanced gastric cancer.

Minimally invasive management of colon cancer

One of the most controversial issues in minimally invasive surgery has been the implementation of laparoscopic techniques for the curative resection of colorectal malignancies. Initial concerns included the potential violation of oncologic principles, the effects of carbon dioxide, and the phenomenon of port site tumor recurrence. Basic science research and large randomized controlled trials are now demonstrating that these fears were unjustified. Long-term outcomes of laparoscopic colon resection compared with open colon resection for malignancy are comparable, and there may even be a survival benefit for a subset of patients who undergo laparoscopic resection.

Prevention and management of complications in urological laparoscopic port site placement

OBJECTIVES

To review complications associated with urological laparoscopic port-site placement and outline techniques for their prevention and management.

METHODS

Review of the literature using Medline.

RESULTS

Laparoscopy now plays a key role in urological surgery. Its applications are expanding with experience and evolving data confirming equivalent long-term outcome. Although significant port-site complications are uncommon, their occurrence impacts significantly on perioperative morbidity and rate of recovery. The incidence of such complications is inversely related to surgeon experience. Ports now utilise bladeless tips to reduce the incidence of vascular and visceral injuries, and subsequently port-site herniation. Metastases occurring at the port site are preventable by adhering to certain measures.

CONCLUSIONS

Whether performing standard or robot-assisted laparoscopy, port-site creation and maintenance is critical in ensuring minimal invasiveness in laparoscopic urological surgery. Although patient factors can be optimised perioperatively and port design continues to improve, it is clear that adequate training is central in the prevention, early recognition, and treatment of complications related to laparoscopic access.

Surgical strategies in patients with gallbladder cancer: nihilism to optimism

INTRODUCTION

Gallbladder cancer is an aggressive disease with dismal results of surgical treatment and a poor prognosis. However, over the last few decades selected groups have reported improved results with aggressive surgery for gallbladder cancer.

METHODS

Review of recent world literature was done to provide an update on the current concepts of surgical treatment of this disease.

RESULTS

Long-term survival is possible in early stage gallbladder carcinoma. Tis and T1a gallbladder carcinoma can be treated with simple cholecystectomy only. However, in T1b and beyond cancers, aggressive surgery (extended cholecystectomy) is important in improving the long-term prognosis. Laparoscopic cholecystectomy should not be performed where there is a high index of suspicion of malignancy due to the frequent association with factors (such as gallbladder perforation and bile spill) which may lead to implantation of cancer cells and dissemination. Surgical resection for advanced carcinoma gallbladder is recommended only if a potentially curative R0 resection is possible. Aggressive surgery with vascular and multivisceral resection has been shown to be feasible albeit with an increase in mortality and morbidity. However, the true benefit of these radical resections is yet to be realized, as the actual number of long-term survivors of advanced gallbladder carcinoma is few.

CONCLUSIONS

Surgery for gallbladder carcinoma, like other malignancies, has the potential to be curative only in local or regional disease. Pattern of loco-regional spread of disease dictates the surgical procedure. Radical surgery improves survival in early gallbladder carcinoma. The long-term benefit of aggressive surgery for advanced disease is unclear and may be offset by the high mortality and morbidity.

The Role of Laparoscopy in Ovarian Tumors of Low Malignant Potential and Early-Stage Ovarian Cancer

Although it is feasible today to perform laparoscopic surgical staging and treatment of ovarian low malignant potential tumors and early-stage ovarian cancer safely, it is still generally agreed that a patient with ovarian cancer should have a laparotomy. Concerns related to laparoscopy in managing gynecologic malignancy include the accuracy of intraoperative diagnosis, inadequate resection, significance of tumor spillage, improper or delay in surgical staging, delay in therapy, and the possibility of port-site metastasis. On the other hand, laparoscopy has the advantages of being a minimally invasive surgery, with shorter hospitalization, decreased postoperative pain, and quicker return to normal daily activities. We review the current literature discussing the consequences of laparoscopic surgery in ovarian tumors of low malignant potential and early-stage ovarian cancer.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to list the concerns related to laparoscopic management of ovarian malignancies, to outline the accuracy of the diagnosis of low malignant potential (LMP) ovarian tumors on frozen section, and to summarize the data on the effect of capsule rupture on overall prognosis for patients with ovarian cancer.

Port-Site Metastasis: The Influence of Biology

OBJECTIVE

Several surgical and technical mechanisms have been proposed for the development of port-site metastasis, but the influence of tumor and host biologic factors has not been emphasized. We present a case of a pelvic chordoma that metastasized to a prior laparoscopic radical nephrectomy port-site.

METHODS

A 62-year-old woman underwent laparoscopic radical nephrectomy (LRN) for a pT1b grade 3 renal cell carcinoma, followed 6 weeks later by resection of a sacral chordoma. The incisions and areas of dissection for the two procedures were discontinuous.

RESULTS

Eight months following the LRN she developed a nodule in one of the laparoscopic port-sites. The port-site metastasis was treated with wide surgical resection, which was confirmed as metastatic chordoma on histologic examination.

CONCLUSION

Based on the chronological sequence and physical distance between surgical sites, only biological factors could have contributed to this port-site metastasis. This unusual case highlights the important role that tumor and host biologic mechanisms play in the development of port-site metastasis.

Effect of carbon dioxide pneumoperitoneum and wound closure technique on port site tumor implantation in a rat model

BACKGROUND

The purpose of this study was to evaluate the effects of carbon dioxide (CO2) pneumoperitoneum and wound closure technique on port site tumor implantation.

METHODS

A standard quantity of rat mammary adenocarcinoma (SMT2A)was allowed to grow in a flank incision in Wistar-Furth rats (n = 90) for 14 days. Thereafter, 1-cm incisions were made in each animal in three quadrants. There were six control animals. The experimental animals were divided into a 60-min CO2 pneumoperitoneum group (n = 42) and a no pneumoperitoneum (n = 42) group. The flank tumor was lacerated transabdominally in the experimental groups. The three wound sites were randomized to closure of (a) skin; (b) skin and fascia; and (c) skin, fascia, and peritoneum. The abdominal wounds were harvested en bloc on postoperative day 7.

RESULTS

Histologic comparison of the port sites in the pneumoperitoneum and no-pneumoperitoneum groups did not demonstrate a statistically significant difference in tumor implantation for any of the closure methods. Evaluation of the closure techniques showed no statistical difference between the pneumoperitoneum group and the no-pneumoperitoneum group in the incidence of port site tumor implantation. Within the no-pneumoperitoneum group, there was a significant increase (p = 0.03) in tumor implantation with skin closure alone vs all three layers. Additionally, when we compared all groups by closure technique, the rate of tumor implantation was found to be significantly higher (p = 0.01) for skin closure alone vs closure of all three layers.

CONCLUSIONS

This study suggests that closure technique may influence the rate of port site tumor implantation. The use of a CO2 pneumoperitoneum did not alter the incidence of port site tumor implantation at 7 days postoperatively.

Gallbladder cancer treatment using adenovirus expressing the HGF/NK4 gene in a peritoneal implantation model

Gallbladder cancer cells are stimulated by hepatocyte growth factor (HGF) in vitro and in vivo. We constructed an adenovirus vector, AdCMV.NK4, carrying the HGF antagonist HGF/NK4 (NK4) and evaluated whether or not this vector can suppress the peritoneal implantation of gallbladder cancer in a novel peritoneal injury mouse model. A human gallbladder cancer cell line (GB-d1) and human peritoneal mesothelial cells infected with the adenovirus vector produced a substantial level of NK4 protein. An invasion of GB-d1 cells was determined by a coculture with AdCMV.NK4-infected human mesothelial cells in vitro. Both the invasion and migration of GB-d1 cells were dramatically inhibited by this vector in a multiplicity of infection (MOI)-dependent manner. GB-d1 cells were intraperitoneally injected into the nude mice with peritoneal injury, followed by either AdCMV.NK4 or a control vector (AdCMV.LacZ). The incidence and the size of the metastatic tumor drastically decreased by AdCMV.NK4 (MOI 100: n=4, P<.0001). Real-time PCR analysis revealed a transient elevation of mouse HGF mRNA expression at the peritoneal injury sites. AdCMV.NK4 has been suggested to induce the inhibition of the implantation and growth of gallbladder cancer cells in vivo through its anti-HGF activity, and the use of NK4 gene transfer could be an effective modality for preventing peritoneal metastasis of gallbladder cancer.

Abandoned endoscopic procedures

Intraoperatively, it may be prudent at times to abandon or defer the intended therapeutic procedure due to adverse prevailing conditions. A decision to abandon or defer an endoscopic procedure would necessarily result in less morbidity compared with conventional open surgery. A retrospective review of endoscopic procedures that were abandoned or deferred and subsequent patient outcomes were noted. Between January 1998 to May 2003, 48 procedures out of a total of 11,550 endoscopic surgical procedures had to be abandoned. Previously unsuspected intraabdominal malignancy was the cause in 32 patients. Anesthesia-related problems led to the decision in 6 patients. Coincidental tuberculosis and failure in accessing the target organ were the cause in two patients each. An ectopic gallbladder, an absent gallbladder, a pancreatic phlegmon, and a failure to achieve proper single-lung ventilation led to the decision in one patient each. In two patients, presence of dense intraabdominal adhesions that precluded further progress led the surgeon to abandon the surgery. The patients with intraabdominal malignancy were staged for their disease and treated accordingly. Nine patients without malignancy who had their operation deferred due to diverse reasons were operated on a later date, whereas 4 patients were lost to follow-up. The 9 patients who underwent operation at a later date are well on follow-up. Four patients with intraabdominal malignancy died, whereas the others are well in follow-up after being treated according to the stage of their disease. Certain adverse situation encountered intraoperatively may lead the surgeon to change the approach to surgery and abandon the procedure. He may consider operation at a suitable time later or consider a different treatment altogether. The morbidity consequent to such a decision is much less if the operative approach is an endoscopic one.

Tumour seeding in peritoneal wound sites in relation to growth-factor expression in early granulation tissue

The purpose of these experiments was to identify growth factors produced during the formation of a peritoneal wound in relation to tumour cell seeding and stimulated growth in granulation tissue. Gelfoam(c) gelatin sponge was implanted in the mesenteric fan of nude mice to initiate the granulation process. Human HT29 colon carcinoma cells were inoculated intraperitoneally at various times after sponge implantation and tumour growth in granulation tissue was determined. RNA isolated from granulation tissue was used for polymerase chain reaction analysis of the expression of specific growth factors and receptors [vascular endothelial growth factor (VEGF), transforming growth factor-beta (TGF-beta) and lysophosphatic acid (LPA)], and for microarray analysis of differentially expressed genes in early vs. late granulation tissue. Inflammatory cells infiltrated the sponge within 1 day, followed by fibroblasts and the formation of an extracellular matrix. Tumour cell inoculation at 8 h to 3 days after sponge implantation resulted in extensive tumour formation in all cases. Inoculation at 10-28 days resulted in focal tumour growth in only 16-33% of the sponges. Low amounts of VEGF, TGF-beta(1-3), TGF-beta RIII and LPA receptors 1,2 were detected in early granulation tissue, with increased expression from day 10. Microarray analysis identified additional differentially expressed genes that may stimulate tumour take and growth in early granulation tissue.

Port site metastases in urological laparoscopic surgery

PURPOSE

Laparoscopic surgery is rapidly gaining widespread acceptance among urologists, including extensive application in malignant conditions. However, untoward occurrences of port site metastases have not eluded to urological applications. This up-to-date review on port site metastases in urology delineates possible contributing factors and describes techniques to prevent it.

MATERIALS AND METHODS

We comprehensively reviewed published experimental and clinical studies with special emphasis on the incidence, pathophysiology and prevention of port site metastases.

RESULTS

Nine cases of port site metastases after urological laparoscopy have been described in clinical and experimental studies. Etiological factors include natural malignant disease behavior, host immune status, local wound factors, laparoscopy related factors such as aerosolization of tumor cells (the use of gas, type of gas, insufflation and desufflation, and pneumoperitoneum) and sufficient technical experience of the surgeons and operating team (adequate laparoscopic equipment, skill, minimal handling of the tumor, surgical manipulation and wound contamination during instruments change, organ morcellation and specimen removal).

CONCLUSIONS

Port site metastases is a multifactorial phenomenon with an as yet undetermined incidence. The problem is influenced to some extent by surgeon and operating team experience and, therefore, it could be partially prevented. The suggested preventive steps are avoiding laparoscopic surgery when there are ascites, trocar fixation to prevent dislodgment, avoiding gas leakage along and around the trocar, sufficient technical readiness of the operating team (adequate laparoscopic equipment and technique, minimal handling and avoiding tumor boundary violation of the tumor), using a bag for specimen removal, placing drainage when needed before desufflation, povidone-iodine irrigation of instruments, trocars and port site wounds, and suturing 10 mm. and larger trocar wounds.

Curative treatment of gastric cancer: towards a multidisciplinary approach?

Despite marked decreases in incidence over the last century, particularly in developed countries, gastric cancer is still the second-most common tumor worldwide. Surgery remains the gold standard for the cure of locoregional disease. However, in most countries, the diagnosis is made at an advanced stage, and the 5-year survival for surgically resectable disease stays far below 50%. The efficacy of chemotherapy and/or radiation therapy in addition to surgery has been actively studied over the last 30 years. Unfortunately, with few exceptions, most studies of adjuvant therapy in gastric cancer have given deceiving results. The purpose of this review is to address the reasons for our failure to objectivate an improvement in the cure of gastric cancer with adjuvant treatment in most trials, and to consider potential solutions. The low efficacy of chemotherapy regimens available up to now may have hampered our progress. In addition, many previous studies suffered limitations of design or methodology (e.g. low accrual, inadequate disease stage selection, inadequate surgical treatment) that may have obscured a treatment effect. Furthermore, the reduced treatment tolerance of post-gastrectomy patients, perhaps due to their poor nutritional status, results in decreased or delayed adjuvant systemic therapy, with potential adverse consequences in its efficacy. Among potential solutions, the arrival of new drugs, taxanes and topoisomerase I inhibitors in particular, which have shown encouraging results in metastatic disease, may increase the impact of chemotherapy in a multidisciplinary treatment approach. Pre-treatment with chemotherapy and/or radiation therapy prior to surgery may also be advantageous, averting the problems associated with post-surgical treatment. Such an approach has been shown to be feasible in phase II studies, and is relatively well tolerated by patients. Several carefully designed randomized phase III trials are underway to answer this question.

Peritoneal mesothelial hypoxia during pneumoperitoneum is a cofactor in adhesion formation in a laparoscopic mouse model

OBJECTIVE

To develop a laparoscopic mouse model to evaluate the hypothesis that mesothelial hypoxia during pneumoperitoneum is a cofactor in adhesion formation.

DESIGN

Prospective randomized trials.

SETTING

Academic research center.

ANIMAL(S)

One hundred thirty female Naval Medical Research Institute (NMRI) mice.

INTERVENTION(S)

Adhesions were induced by opposing monopolar lesions in uterine horns and pelvic side walls during laparoscopy and evaluated after 7 or 28 days under microscopic vision during laparotomy. The following pneumoperitoneum variables were assessed: duration (10 or 60 minutes), insufflation pressure (5 or 15 cm of water), insufflation gas (CO(2) or helium), and addition of oxygen (0-12%).

MAIN OUTCOME MEASURE(S)

Adhesions were scored quantitatively and qualitatively for extent, type, and tenacity.

RESULT(S)

Scoring of adhesions 7 or 28 days after laparoscopic surgery was comparable. Adhesions increased with duration of pneumoperitoneum and with insufflation pressure and decreased with the addition of oxygen. Half-maximal reduction of adhesions was obtained at 1.5% oxygen, whereas a maximal reduction required only 2%-3%. The effect of CO(2) and helium was similar.

CONCLUSION(S)

These data demonstrate the feasibility of the intubated laparoscopic mouse model and confirm previous observations in rabbits, indicating that mesothelial hypoxia plays a key role in adhesion formation.

Morphology of the murine peritoneum after pneumoperitoneum vs laparotomy

BACKGROUND

Although there have been studies of the effects of pneumoperitoneum on the peritoneal cavity, we still do not know whether the morphologic changes to the peritoneum are different for pneumoperitoneum vs laparotomy. Using scanning electron microscopy, we examined the murine peritoneum after pneumoperitoneum vs laparotomy and compared the changes.

METHODS

Forty-five mice were anesthetized with diethyl ether and divided into seven groups. Pneumoperitoneum was established at 5 mmHg for 30 min with carbon dioxide (CO(2)) (n = 9), helium (n = 9), and air (n = 9). One group underwent laparotomy for 30 min (n = 9), and a control group underwent anesthesia only (n = 3). CO(2) pneumoperitoneum was further established at 10 mmHg for 30 min (n = 3) and at 5 mmHg for 60 min (n = 3). After the procedures, the peritoneum was resected from the mesenterium of the small intestine in each animal and examined by scanning electron microscope for morphologic changes of the mesothelial cells.

RESULTS

Bulging up of the mesothelial cells was evident immediately after pneumoperitoneum, whereas detachment of the mesothelial cells was present immediately after laparotomy. Bulging up of the mesothelial cells was reduced at 24 h after CO(2) pneumoperitoneum and fully resolved at 72 h in all pneumoperitoneum groups, whereas the mesothelial cells remained detached at 72 h in the laparotomy group. Intercellular clefts were found immediately after helium pneumoperitoneum and were present at 24 h and 72 h after helium pneumoperitoneum, but they were not seen after air pneumoperitoneum and were only evident after CO(2) pneumoperitoneum at 10 mmHg. Depression of the mesothelial cell surface was observed when pneumoperitoneum lasted 60 min.

CONCLUSION

Morphologic peritoneal alterations after pneumoperitoneum differed from those after laparotomy and were influenced by the type of gas, amount of pressure, and duration of insufflation. These peritoneal changes after pneumoperitoneum may be associated with a specific intraperitoneal tumor spread after laparoscopic cancer surgery.

Experimental assessment of tumor growth and dissemination of a microscopic peritoneal carcinomatosis after CO2 peritoneal insufflation or laparotomy

BACKGROUND

Based on clinical observations and previous animal studies, laparoscopic surgery for malignant disease is regarded as controversial. We used a rat model to measure and compare the tumor growth, proliferation, and dissemination of a microscopic peritoneal carcinomatosis after CO(2) intraperitoneal insufflation or laparotomy.

METHODS

Peritoneal carcinomatosis was induced in three groups of 27 BD IX rats each with intraperitoneal injections of 106 DHD/K12 cells, an aneuploid tumor cell line. At 48 h after tumor cell injection, the animals were randomly divided into three groups to undergo different types of intervention. All animals were anesthetized for 20 min (Halothane). The control group had no surgical intervention (group C), group I had CO(2) insufflation (7 mmHg),and group L had a midline laparotomy (5-cm). Neither bowel manipulation nor any other traumatic action was performed. Two weeks later, the rats were killed and the incidence, type, and dissemination of carcinomatosis were evaluated. We also measured the tumor's weight. Malignant omentum was sampled for flow cytometry analysis (DNA ploidy, S-phase fraction).

RESULTS

The incidence of carcinomatosis did not differ among the groups. The mean score of macroscopic characteristics of the carcinomatosis was 2.8 +/- 1.9 in group L, 2.9 +/- 1.9 in group I, and 3 +/- 1.9 in group C (NS). The location of the implants did not differ, except for parietal peritoneum location, which was more frequent in group L (p < 0.01). The tumor weight was 4.96 g +/- 3.2 in group L, 5.55 g +/- 3.2 in group C, and 5.75 g +/- 3.4 in group I (NS). The percentage of aneuploid cells and S-phase fraction did not differ statistically among the groups.

CONCLUSION

These results indicate that CO(2) insufflation does not cause more effects than laparotomy when tumors cells are present before the beginning of the surgery. Further studies are needed to determine the influence of other steps in laparoscopic surgery on tumor growth and dissemination.

Risk of spread of ovarian cancer after laparoscopic surgery

The incidence of the spread of ovarian cancer after laparoscopic surgery is difficult to establish from the current literature. The prognosis incidence of a trocar site metastasis without peritoneal dissemination is not known. Data from general surgeons in prospective studies from a single institution suggested that in colon cancer the risk is low, whereas it seems to be much higher in multicentric studies of undiagnosed gallbladder cancer. Experimental studies suggested that laparoscopy has advantages and disadvantages. However, the risk of dissemination is high when a large number of malignant cells and a carbon dioxide pneumoperitoneum are present, a situation encountered when managing adnexal tumours with large vegetations. Animal studies will allow the development of a peritoneal environment adapted to the treatment of cancer. The ovary is an intraperitoneal organ and ovarian cancer a peritoneal disease, so the risk of peritoneal spread may be higher in ovarian cancer than in other gynecological cancers. A careful preoperative evaluation appears to be the best way to prevent these risks. It should also be used to choose which patient should be operated by which surgical team. The second step is a careful and cautious laparoscopic diagnosis, so that more than 98% of ovarian cancers encountered can be treated immediately and effectively. The laparoscopic management of ovarian cancer remains controversial; it should be performed only in prospective clinical trials. Until the results of such studies become available, an immediate vertical midline laparotomy remains the gold standard if a cancer is encountered.

Hyaluronic acid secretion during carbon dioxide pneumoperitoneum and its association with port-site metastasis in a murine model

BACKGROUND

The mechanism of port-site metastasis after laparoscopic cancer surgery is unclear. This study aimed to determine whether carbon dioxide (CO2) pneumoperitoneum caused an increase in hyaluronic acid, which is secreted from mesothelial cells of the peritoneal cavity, and to assess the risk for port-site metastasis using a murine pneumoperitoneal model.

METHODS

Sandwich-binding protein assay was used to measure the concentration of hyaluronic acid in the peritoneal cavity at 6, 12, 18, 24, 48, and 72 h after CO2 pneumoperitoneum or laparotomy for 30 min. The concentrations of hyaluronic acid during pneumoperitoneum were compared among different gases (CO2, helium, air), intervals (5, 30, 60 min), and pressures (0-2, 4-6, 8-10 mmHg). To investigate the effects of exogenous hyaluronic acid, the development of port-site metastasis was examined using mouse adenocarcinoma cell-line colon 26 cells.

RESULTS

The intraperitoneal concentration of hyaluronic acid after CO2 pneumoperitoneum had increased already at 6 h, had reached the maximum level at 24 h, and had begun to decrease at 72 h. The concentration of hyaluronic acid at 24 h and 48 h in the CO2 pneumoperitoneum group was higher than that in the laparotomy group. This increase in hyaluronic acid also was found during helium and air pneumoperitoneum, and the concentration of hyaluronic acid in the peritoneal cavity was at its maximum when CO2 pneumoperitoneum lasted 30 min at 4 to 6 mmHg. The frequency of port-site metastasis was the highest when hyaluronic acid was injected during CO2 pneumoperitoneum (100%).

CONCLUSIONS

In a murine model, the intraperitoneal concentration of hyaluronic acid was significantly increased after CO2 pneumoperitoneum, and the increase was more evident than that after laparotomy. Increased hyaluronic acid during pneumoperitoneum may be associated with port-site metastasis after laparoscopic cancer surgery.

Laparoscopic cholecystectomy in the treatment of patients with gall bladder cancer

BACKGROUND

Surgical procedures based on the depth of the primary tumor invasion (pT category) have been proposed in the treatment of gallbladder cancer (GBC). Trocar site metastases have been reported in patients who underwent laparoscopic cholecystectomy (LC) for preoperatively undiagnosed GBC.

STUDY DESIGN

The aim of this study was to clarify the role of LC as a surgical strategy for GBC. From 1986 to 1998, 56 patients with GBC underwent surgical resection. Survival rates were compared retrospectively according to pT category and use of LC.

RESULTS

Five-year survival was 91% for pT1 (n = 13), 64% for pT2 (n = 25), 34% for pT3 (n = 14), and 0% for pT4 tumors (n = 4; p<0.0001). LC was performed on 11 patients (4 with pT1, 5 with pT2, and 2 with pT3 tumors). Of the seven patients with pT2 or pT3 tumors, three underwent a second radical operation, three had an open radical operation to which the procedure was converted from LC, and one underwent no additional procedures. For pT1 tumors, one patient died of trocar site metastasis from bile spillage after LC. For pT2 or pT3 tumors, 5-year survival was 63% for radical surgery (n = 35) and 0% for cholecystectomy alone (n = 4; p<0.05). For pT2 or pT3 tumors treated by radical surgery, 5-year survival was 75% for laparoscopic approach (n = 6) and 60% for open surgery (n = 29; not significant).

CONCLUSIONS

LC may help to establish the diagnosis and to determine the surgical strategy for undiagnosed GBC. It is important to prevent spillage or implantation of malignant cells during LC. For pT2 or pT3 tumors diagnosed laparoscopically, a second or converted open radical surgery is necessary.

Radical surgery for gallbladder cancer: current options

Gallbladder carcinoma is the most common malignancy of the biliary tract. There are still many controversies regarding the type of curative surgical treatment for each stage of the disease. The staging system used is the TNM classification of the International Union Against Cancer. Different patterns of spread characterize gallbladder cancer but the two main types are direct invasion and lymph node metastases; since only the depth of invasion can be easily recognized by imaging techniques, it becomes the main variable in choosing the appropriate surgical treatment. Most Tis and T1 tumours are incidentally discovered after cholecystectomy for cholelithiasis and no further therapy is requested; for pT1b tumours, relaparotomy with hepatic resection and N1 dissection is associated with a better survival. For T2 tumours, cholecystectomy with hepatic resection and dissection of N1-2 lymph nodes is the standard treatment, with a 5-year survival of 60-80%. The only chance of long-term survival for patients with a T3-T4 tumour is an extended operation combining an hepatic resection with an N1-2 dissection with or without excision of the common bile duct. A subset of patients with peripancreatic positive nodes or invasion of adjacent organs seems to benefit from a synchronous pancreaticoduodenectomy.