Enhancement of port site metastasis by hyaluronic acid under CO2 pneumoperitoneum in a murine model

Polysaccharides as submucosal injection materials (SIMs) in endoscopic resection: A comprehensive review

Submucosal injection materials (SIMs) play a vital role in the endoscopic treatment of benign and early malignant gastrointestinal lesions by effectively elevating lesions while significantly reducing the risks of thermal injury and bleeding. However, the traditional use of normal saline (NS) presents challenges due to its rapid absorption, which necessitates frequent reapplications and complicates procedural efficiency. Therefore, there is a pressing need for ideal SIMs that are cost-effective, readily available, and suitable for personalized therapy, while also demonstrating excellent biocompatibility and physicochemical stability. Recent advancements have highlighted the potential of polysaccharide-based natural polymers, such as sodium hyaluronate, cellulose, starch derivatives, chitosan, and sodium alginate, due to their superior biocompatibility and biodegradability. These polysaccharides have exhibited enhanced operational characteristics and therapeutic efficacy in animal and clinical studies. Nevertheless, ongoing research must address several challenges, including optimizing cost-effectiveness, improving mechanical strength and bioactivity, and mitigating intraoperative and postoperative complications. This review systematically examines the progress of polysaccharide-based natural polymers in SIMs, evaluates their current status and challenges in both research and clinical applications, and proposes future directions to enhance their utilization in gastrointestinal endoscopic therapy.

Minimally Invasive Surgery for Cervical Cancer in Light of the LACC Trial: What Have We Learned?

Cervical cancer is the most common gynecologic malignancy and the fourth most common cancer in women worldwide. Over the last two decades, minimally invasive surgery (MIS) emerged as the mainstay in the surgical management of cervical cancer, bringing advantages such as lower operative morbidity and shorter hospital stay compared to open surgery while maintaining comparable oncologic outcomes in numerous retrospective studies. However, in 2018, a prospective phase III randomized controlled trial, “Laparoscopic Approach to Carcinoma of the Cervix (LACC)”, unexpectedly reported that MIS was associated with a statistically significant poorer overall survival and disease-free survival compared to open surgery in patients with early-stage cervical cancer. Various hypotheses have been raised by the authors to try to explain these results, but the LACC trial was not powered to answer those questions. In this study, through an exhaustive literature review, we wish to explore some of the potential causes that may explain the poorer oncologic outcomes associated with MIS, including the type of MIS surgery, the size of the lesion, the impact of CO2 pneumoperitoneum, prior conization, the use of uterine manipulator, the use of protective measures, and the effect of surgical expertise/learning curve.

Solitary port-site metastasis 42 months after laparoscopic distal gastrectomy for gastric cancer

We report a case of solitary port-site recurrence after laparoscopy-assisted distal gastrectomy for advanced gastric cancer. A 66-year-old man had previously undergone laparoscopy-assisted gastrectomy with regional lymph-node dissection for advanced gastric cancer, which was a poorly differentiated adenocarcinoma invading the subserosal layer with lymphatic infiltration and no lymph-node metastases. He experienced dull pain in the left upper quadrant of the abdomen 42 months after the surgery. On physical examination, erythematous induration of the skin around the scar of the port insertion was observed in the left upper quadrant of the abdomen. Abdominal ultrasonography and contrast-enhanced computed tomography revealed a subcutaneous lesion with a well-defined mass measuring 3.0 cm in diameter located in the left upper quadrant of the abdomen. A skin biopsy revealed a metastatic adenocarcinoma from gastric cancer. Since there was no evidence of further metastatic lesions in other organs, the patient underwent surgical resection of the metastatic tumor arising at the port site. The abdominal wall tumor was resected with a leaf-skin incision and an adequate safety margin, and the inferior border of the tumor reached the muscular layer, which was resected with the tumor. Pathological examination confirmed the diagnosis of a poorly differentiated adenocarcinoma in the subcutaneous tissue with invasion of the muscle layer at the port site. The postoperative course was uneventful; chemotherapy using oxaliplatin plus S-1 was administered, and the patient was in good health with no evidence of the disease for 3 months postoperatively. Although port-site metastasis after laparoscopic gastrectomy for gastric cancer is a rare recurrence form, we should be aware of this issue, and further studies and assessments of additional cases are needed to establish a treatment strategy.

Port-Site Metastases and Chimney Effect of B-Ultrasound-Guided and Laparoscopically-Assisted Hyperthermic Intraperitoneal Perfusion Chemotherapy

PURPOSE

CO₂ leakage along the trocar (chimney effect) has been proposed to be an important factor underlying port-site metastasis after laparoscopic surgery. This study aimed to test this hypothesis by comparing the incidence of port-site metastasis between B-ultrasound-guided and laparoscopically-assisted hyperthermic intraperitoneal perfusion chemotherapy (HIPPC).

MATERIALS AND METHODS

Sixty-two patients with malignant ascites induced by gastrointestinal or ovarian cancer were divided into two groups to receive either B-ultrasound-guided or laparoscopically-assisted HIPPC. Clinical efficacy was assessed from the objective remission rate (ORR), the Karnofsky Performance Status (KPS) score, and overall survival. The incidence of port-site metastasis was compared between the two groups.

RESULTS

Patients in the B-ultrasound (n=32) and laparoscopy (n=30) groups were comparable in terms of age, sex, primary disease type, volume of ascites, and free cancer cell (FCC)-positive ascites. After HIPPC, there were no significant differences between the B-ultrasound and laparoscopy groups in the KPS score change, ORR, and median survival time. The incidence of port-site metastasis after HIPPC was not significantly different between the B-ultrasound (3 of 32, 9.36%) and laparoscopy (3 of 30, 10%) groups, but significantly different among pancreatic, gastric, ovarian, and colorectal cancer (33.33, 15.79, 10.00, and 0.00%, p<0.001).

CONCLUSION

The chimney effect may not be the key reason for port-site metastasis after laparoscopy. Other factors may play a role, including the local microenvironment at the trocar site and the delivery of viable FCCs (from the tumor or malignant ascites) to the trauma site during laparoscopic surgery.

Adhesion molecules in peritoneal dissemination: function, prognostic relevance and therapeutic options

Peritoneal dissemination is diagnosed in 10–25 % of colorectal cancer patients. Selected patients are treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. For these patients, earlier diagnosis, optimised selection criteria and a personalised approach are warranted. Biomarkers could play a crucial role here. However, little is known about possible candidates. Considering tumour cell adhesion as a key step in peritoneal dissemination, we aim to provide an overview of the functional importance of adhesion molecules in peritoneal dissemination and discuss the prognostic, diagnostic and therapeutic options of these candidate biomarkers. A systematic literature search was conducted according to the PRISMA guidelines. In 132 in vitro, ex vivo and in vivo studies published between 1995 and 2013, we identified twelve possibly relevant adhesion molecules in various cancers that disseminate peritoneally. The most studied molecules in tumour cell adhesion are integrin α2β1, CD44 s and MUC16. Furthermore, L1CAM, EpCAM, MUC1, sLe^x and Le^x, chemokine receptors, Betaig-H3 and uPAR might be of clinical importance. ICAM1 was found to be less relevant in tumour cell adhesion in the context of peritoneal metastases. Based on currently available data, sLe^a and MUC16 are the most promising prognostic biomarkers for colorectal peritoneal metastases that may help improve patient selection. Different adhesion molecules appear expressed in haematogenous and transcoelomic spread, indicating two different attachment processes. However, our extensive assessment of available literature reveals that knowledge on metastasis-specific genes and their possible candidates is far from complete.

Effects of a simulated CO2 pneumoperitoneum environment on the proliferation, apoptosis, and metastasis of cervical cancer cells in vitro

BACKGROUND

This study aimed to investigate the growth curve, cell colony formation, cell cycle, apoptosis, anti-anoikis, and ability of invasion, adhesion, and migration of cervical cancer cells after exposure to a model of a simulated CO2 pneumoperitoneum environment with different pressures and at different times.

MATERIAL AND METHODS

The cervical cancer cells were cultured in groups with 8 and 16 mmHg of 100% CO2 for 1, 2, 3, and 4 h in a model of a simulated environment of CO2 pneumoperitoneum. The cells in the control group were cultured in a standard environment. The growth curve was drawn through constant survival cell counts for 7 days, and the group with most obvious change was selected for subsequent experiments to detect cell colony formation, cell cycle apoptosis, and anti-anoikis, and the ability of invasion, adhesion, and migration.

RESULTS

After a brief inhibition, the proliferation of cervical cancer cells was markedly increased and had no relationship with different CO2 pressures. Compared with the control group, the early apoptosis rate in the experimental group was higher, and the ability of invasion, migration, and adhesion decreased significantly.

CONCLUSIONS

Cervical cancer cells stimulated by a CO2 pneumoperitoneum environment in vitro have an increased the ability to proliferate after a short period of inhibition and have reduced abilities of invasion, migration, and adhesion.

Evaluation of short-term outcomes after laparoscopically assisted abdominoperineal resection for low rectal cancer

BACKGROUND

To investigate the feasibility, safety and short-term efficacy of laparoscopic techniques applied in the abdominoperineal resection (APR) for low rectal cancer.

METHODS

The clinical data of 236 patients with APR from January 2010 to January 2012 were analysed retrospectively, including 100 patients underwent laparoscopically assisted APR (LAAPR group), 136 cases of open APR (OAPR group). The demographics, tumor and procedure-related parameters, perioperative results and short-term oncological outcomes were evaluated using t-test or χ(2) -test.

RESULTS

The demographic data of the two groups were comparable. Perioperative results were better after laparoscopic surgery, with less intraoperative blood loss (P = 0.017), earlier return of bowel function (P < 0.05) and lower complication rates (P = 0.015). No significant differences were detected between the two groups in operation time, tumor size, specimen length, the distance of tumor from the anal verge, lymph nodes removed and the status of circumferential resection margin (P > 0.05). During the follow-up period of 17-38 months (average, 26 months), the overall survival rates were not significantly different between the two groups [82.5% (80/97) versus 82.7% (110/133), P > 0.05]. The differences in recurrence and metastasis between the two groups were not statistically significant.

CONCLUSION

Laparoscopically assisted APR for low rectal cancer is safe and effective. It has the advantages of less bleeding, rapid postoperative recovery and fewer complications, without affecting the radical degree of the surgery. Further studies are needed to fully assess oncological outcomes in the future.

Low incidence of port-site metastases after laparoscopic staging of uterine cancer

OBJECTIVE

To estimate the incidence of clinically detected port-site metastases (PSM) in patients with endometrial and cervical cancer treated at two gynecologic oncology services with extensive experience.

METHODS

All eligible uterine cancer patients laparoscopically staged at Centre Oscar Lambret in Lille and Institut Claudius Regaud in Toulouse, France, were reviewed. MEDLINE database was searched to identify articles on PSM after laparoscopic procedures for cervical and endometrial cancer.

RESULTS

During the study period, 1216 laparoscopic procedures for uterine cancer were performed. 921 patients underwent laparoscopic staging for cervical cancer and 295 for endometrial cancer. The overall incidence of PSM in our institutions was 0.4% per procedure (5 patients), and the incidence of PSM after laparoscopy for cervical and endometrial cancer was 0.43% and 0.33%, respectively. Excluding patients with peritoneal carcinomatosis, the rate of port-site recurrence in our series lowered to 0.16%, and the rate of isolated PSM to 0%. The median time to the development of PSM was 8 months (range 6-48), the median overall survival from diagnosis for all patients was 26 months (range 7-30), and median survival from recurrence was 5 months (range 1-20).

CONCLUSION

Although PSM is recognized as a complication of laparoscopy for ovarian cancer. PSM is a rare complication of laparoscopic staging for endometrial and cervical cancer. The majority of patients with PSM presented with associated synchronous disease. The incidence of isolated PSM can be maintained virtually to 0% by an adequate operative technique. We believe that PSM in patients with uterine cancer cannot be used as an argument against laparoscopic staging in uterine cancer.

[Gastric cancer and laparoscopy: analysis of data from the national register of laparoscopic gastric surgery]

OBJECTIVE

To study the data from the Laparoscopic Gastric Surgery Spanish National Register of laparoscopic Gastric Surgery and to analyse the type of surgery, the conversion to laparotomy, postoperative complications and mortality.

PATIENTS AND METHOD

From March 2005 to July 2008, details of 302 laparoscopic gastric surgical interventions were sent to the Association of Spanish Surgeons web-site. Details of surgical technique, reconversion, clinical and pathological data, morbidity and mortality were collected and analysed.

RESULTS

A total of 245 patients had gastric adenocarcinoma, 35 of them stromal tumours and 22 other gastric pathologies. In gastric adenocarcinoma patients, resection was performed in 232 cases (95%). The most frequent histology was intestinal, mainly located in the distal third of the stomach, with 34% of the tumours being locally advanced. D2 lymphadenectomy was performed in 117 cases, D1 in 105, and D0 in 6. Reconversion was needed in 21 cases (9%), with technical difficulty being the most frequent cause. Postoperative complications were reported in 72 patients (31%), with anastomotic leak being one of the most significant. Postoperative mortality was 6%, with sepsis due to anastomotic leak and cardiac or respiratory complications the most frequent causes. The mean hospital stay of patients without complications was 9.2 +/- 3 days.

CONCLUSIONS

Laparoscopic gastrectomy for gastric cancer is a feasible but technically demanding procedure. Potential benefits of minimal invasive surgery can be reduced due to a high rate of postoperative complications.

The addition of 4% oxygen to the CO(2) pneumoperitoneum does not decrease dramatically port site metastases

STUDY OBJECTIVE

Port site metastases (PSM) after laparoscopic surgery for advanced-stage ovarian carcinoma are a cause of concern, but the pathophysiology is unknown. Because CO(2) pneumoperitoneum was recently demonstrated to be a cofactor in adhesion formation and tumor implantation in a laparoscopic mouse model, and because both could be prevented by the addition of 4% oxygen to the CO(2) pneumoperitoneum, we wanted to test the hypothesis that PSM could be related to tumor cell hypoxia during CO(2) pneumoperitoneum.

DESIGN

A randomized controlled pilot trial to compare the incidence of PSM in women undergoing laparoscopy with a pure CO(2) pneumoperitoneum in comparison with women with CO(2) pneumoperitoneum with the addition of 4% oxygen (Canadian Task Force classification C).

SETTING

University Hospital Gasthuisberg, Leuven, Belgium.

PATIENTS

Since January 1, 2007, 22 consecutive women undergoing laparoscopy for suspected ovarian cancer with subsequent debulking laparotomy were included.

INTERVENTIONS

Diagnostic laparoscopy with 100% CO(2) versus laparoscopy with addition of 4% oxygen.

MEASUREMENTS AND MAIN RESULTS

In the control group, 9 (47%) PSM found in 19 port sites were excised. In the CO(2)+oxygen group, a similar incidence was found, that is, 8 (50%) PSM in 16 port sites. The incidence of PSM was higher in small women (p <.018) and in high-grade malignancies. The pathophysiology of PSM is unknown, but besides direct wound contamination, aerosolization of tumor cells and gas leaks have been suggested together with a causal relationship with the CO(2) pneumoperitoneum. Tumor cell hypoxia probably is not an important mechanism because PSM were not prevented by adding small amounts of oxygen to the CO(2) pneumoperitoneum.

CONCLUSION

The hypothesis of tumor cell hypoxia by the CO(2) pneumoperitoneum as a mechanism for PSM could not be confirmed.

ICAM-1 mediated peritoneal carcinomatosis, a target for therapeutic intervention

Development of peritoneal metastasis is a significant issue in the treatment of abdominal cancers. Primary interaction between tumour cells and the mesothelium is a vital step in initiating this process. Our aim was to determine the role of the intercellular adhesion molecule-1 (ICAM-1) in mesothelial-tumour adhesion and the effectiveness of therapeutic intervention. Mesothelial cells were derived from omental tissue. ICAM-1 expression in resting state, in the presence of TNF-alpha or after the application of heparin or hyaluronan was determined by flow cytometry. Functional effects on tumour adhesion to a mesothelial monolayer were determined via a Calcein-AM in vitro adhesion assay. In vivo studies were performed utilising 30 WAG/rij rats, which underwent mini-laparotomy with the injection of 1 x 10(5 )CC 513 tumour cells intraperitoneally. Tumour growth was assessed macroscopically and microscopically by two independent examiners. Mesothelial cells expressed high level of ICAM-1, which was up-regulated by the presence of TNF-alpha. The introduction of heparin caused a decrease in ICAM-1 expression, however hyaluronan did not affect the expression. A significant decrease in tumour-mesothelial cell adhesion in vitro and complete aberration of tumour growth in vivo was observed with heparin application. In vitro studies showed utilisation of high molecular weight hyaluronan, which was more limited in vivo. These data imply that heparin may be used as a potential therapeutic through a defined molecular mechanism both in vitro and in vivo. Hyaluronan appears to function as a barrier and hence may be unreliable in blocking peritoneal recurrence.

Peritoneal nebulizer: a novel technique for delivering intraperitoneal therapeutics in laparoscopic surgery to prevent locoregional recurrence

BACKGROUND

Peritoneal involvement is a significant issue in the treatment of gastrointestinal malignancies. Current statistics indicate that after surgical intervention, up to 20% of patients will present with locoregional metastasis. The ability to inhibit initial tumor adhesion to the mesothelial lining of the peritoneum may be considered critical in the inhibition of tumor development. This article describes, the use of a novel nebulizer system capable of delivering high-concentration, low-dose therapeutics to the peritoneal cavity.

METHODS

For this study, 30 male WAG rats were inoculated with CC531 colorectal tumor cells. The rats were randomized into three groups: control group (n = 10), heparin-treated group (n = 10), and high-molecular-weight hyaluronan-treated group (n = 10). A peritoneal cancer index was used to determine tumor burden at 15 days. Analysis of variance (ANOVA) was used to compare multiple group means.

RESULTS

Nebulization therapy was performed without any complication in the cohort. Heparin inhibited macroscopic intraperitoneal tumor growth completely (p = 0.0001) without affecting tumor cell viability. The introduction of hyaluronan attenuated both tumor size and distribution, was compared with the control group (p = 0.002).

CONCLUSION

Nebulized heparin and hyaluronic acid using a novel nebulization technique attenuates peritoneal tumor growth after laparoscopic surgery. The technique itself is easy to use and safe.

Umbilical metastasis after laparoscopic retroperitoneal paraaortic lymphadenectomy for cervical cancer: a true port-site metastasis?

BACKGROUND

We present a case of umbilical metastasis after laparoscopic retroperitoneal paraaortic lymphadenectomy for cervical cancer.

CASE

A 59-year-old woman with stage IIIB cervical adenocarcinoma underwent laparoscopic paraaortic lymphadenectomy as well as a conventional laparoscopy to assess the presence of peritoneal carcinomatosis. The pathologic examination revealed metastasis in one paraaortic node. Peritoneal cytology proved negative for malignant cells. Seven months after completion of chemoradiotherapy, the patient presented a 2.5-cm umbilical tumor involving the trocar tract together with recurrence of the cervical mass. Histological examination of the excised umbilical mass showed recurrence of the cervical adenocarcinoma, with strong peritumoral CD31 immunocytochemical expression.

CONCLUSION

The peritumoral increase in microvessel density and strong CD31 positivity suggests angiogenesis as a potential factor lead to seeding of tumor cells at the umbilical port.

Hyaluronic acid stimulates tumor-cell proliferation at wound sites

BACKGROUND

For EMR, the submucosal injection of sodium hyaluronate has become popular, because this substance creates a more prominent and longer-lasting mucosal protrusion than normal saline solution. However, the effects of sodium hyaluronate on tumor growth at wound sites remain unclear.

METHODS

For these experiments, a murine model with artificial wounds was used. Forty mice were randomly divided into two groups according to the substance to be injected into a wound: a sodium hyaluronate group and a control group. Tumors were created by inoculation of transplantable adenocarcinoma cell line colon 26. Two weeks later, the size, weight, proliferating cell nuclear antigen-labeling index, and CD44 expression of the subcutaneous tumors were compared between the two groups of mice.

RESULTS

There were significantly greater increases in the growth and the weight of subcutaneous tumors in the sodium hyaluronate group compared with the control group. The PCNA-labeling index of cancer cells also was higher in the sodium hyaluronate group. Immunohistochemistry and Western blot analysis demonstrated that the CD44 protein expression of cancer cells was higher in the sodium hyaluronate group vs. the control group.

CONCLUSIONS

In this study, sodium hyaluronate enhanced both tumor growth and CD44 expression of cancer cells at wound sites, suggesting that the use of sodium hyaluronate for EMR might stimulate the growth of residual tumor cells.

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.

Laparoscopic port-site metastases: etiology and prevention

OBJECTIVE

The purpose of this article is to summarize current hypotheses for the possible sources of laparoscopic port-site metastasis, to review the results of experimental models that support such hypotheses, and to discuss the potential options for preventing these metastases.

METHODS

We performed a Medline search to identify in vitro and in vivo studies and clinical trials that analyzed port-site metastases associated with laparoscopic surgery. We report the incidence of port-site metastases and causative factors associated with this condition.

RESULTS

The estimated incidence of port-site metastases in all patients undergoing laparoscopic surgery for malignant disease is approximately 1-2%. Multiple factors are associated with this complication. Among the most common proposed etiologies are the wound implantations caused by the surgical technique and instrumentation; the leakage of insufflation gas through the ports, known as the "chimney effect"; and the impact of pneumoperitoneum on local immune reactions. Several preventive measures, have been suggested, including careful patient selection, lavage of the peritoneal cavity as well as of the port wounds with cytotoxic agents, and modifications of surgical technique.

CONCLUSIONS

Only through the results of well-conducted large multi-institutional prospective randomized trials will we learn not only the true incidence of port-site metastases, but also the potential factors that lead to the occurrence of this complication.

Increased expression of P-cadherin mRNA in the mouse peritoneum after carbon dioxide insufflation

BACKGROUND

Although systemic responses to carbon dioxide (CO(2)) pneumoperitoneum have been studied, there have been few reports of local responses within the peritoneum. We investigated the expression of mRNA for adhesion molecules involved in cell-cell interactions, including ICAM-1, VCAM-1, CD44, E-cadherin, P-cadherin, and N-cadherin, after the induction of a CO(2) pneumoperitoneum in mice.

METHODS

Mice were treated with CO(2) pneumoperitoneum (4-6 mmHg for 30 min) and then killed after 24 h, 48 h, and 72 h. The peritoneum of the abdominal wall was resected, and total RNA was extracted by the acid guanidinium thiocyanate-phenol-chloroform extraction procedure, cDNA were synthesized by reverse transcription. Expression of the mRNA for each gene was normalized to that of b-actin for semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

The expression of P-cadherin mRNA was significantly increased at 48 h (p = 0.007) and returned to the control level by 72 h after CO(2) pneumoperitoneum. The expression of CD44 increased gradually, reaching a peak at 48 h and returning to the control value by 72 h after CO(2) pneumoperitoneum. Expression of ICAM-1 mRNA was not changed significantly after the application of CO(2).

CONCLUSION

The expression of P-cadherin mRNA in the peritoneum can be induced to repair injuries to mesothelial cells caused by CO(2) pneumoperitoneum.