Systemic and peritoneal angiogenic response after laparoscopic or conventional colon resection in cancer patients: a prospective, randomized trial

Impact of laparoscopic versus open surgery on humoral immunity in patients with colorectal cancer: a systematic review and meta-analysis

BACKGROUND

Laparoscopic surgery (LS) is hypothesized to result in milder proinflammatory reactions due to less severe operative trauma, which may contribute to the observed clinical benefits after LS. However, previous systematic reviews and meta-analyses on the impact of LS on immunocompetence are outdated, limited and heterogeneous. Therefore, the humoral response after laparoscopic and open colorectal cancer (CRC) resections was evaluated in a comprehensive systematic review and meta-analysis.

METHODS

Included were randomized controlled trials (RCTs) measuring parameters of humoral immunity after LS compared to open surgery (OS) in adult patients with CRC of any stage. MEDLINE, Embase, Web of Science (SCI-EXPANDED), Cochrane Library, Google Scholar, ClinicalTrials.gov and ICTRP (World Health Organization) were systematically searched. Risk of bias (RoB) was assessed using the Cochrane RoB2 tool. Weighted inverse variance meta-analysis of mean differences was performed for C-reactive protein (CRP), interleukin (IL)-6, IL-8, tumour necrosis factor (TNF)α and vascular endothelial growth factor (VEGF) using the random-effects method. Methods were prospectively registered in PROSPERO (CRD42021264324).

RESULTS

Twenty RCTs with 1131 participants were included. Narrative synthesis and meta-analysis up to 8 days after surgery was performed. Quantitative synthesis found concentrations to be significantly lower after LS at 0-2 h after surgery (IL-8), at 3-9 h (CRP, IL-6, IL-8, TNFα) and at postoperative day 1 (CRP, IL-6, IL-8, VEGF). At 3-9 h, IL-6 was notably lower in the LS group by 86.71 pg/ml (mean difference [MD] - 86.71 pg/ml [- 125.05, - 48.37], p < 0.00001). Combined narratively, 13 studies reported significantly lower concentrations of considered parameters in LS patients, whereas only one study reported lower inflammatory markers (for CRP and IL-6) after OS.

CONCLUSION

The increase in postoperative concentrations of several proinflammatory parameters was significantly less pronounced after LS than after OS in this meta-analysis. Overall, the summarized evidence reinforces the view of a lower induction of inflammation due to LS.

Effect of laparoscopic liver resection on postoperative delirium in elderly patients with hepatocellular carcinoma

BACKGROUND

Delirium is a multifactorial and heterogeneous syndrome that is defined as acutely altered consciousness. This retrospective multicenter study evaluated the impact of postoperative delirium after liver resection for hepatocellular carcinoma (HCC) in elderly patients.

METHODS

Patients aged ≥75 years, who underwent curative liver resection for HCC at nine university hospitals from April 2010 to December 2017, were evaluated to compare short- and long-term outcomes between patients with and without delirium. Risk factors for delirium were determined using multivariate regression analysis.

RESULTS

The rate of postoperative delirium was 14.2% (n = 80) in the study cohort of 562 patients. Multivariate analysis revealed smoking history, hypertension, sleeping pill consumption, and open liver resection as risk factors for postoperative delirium. The rate of other causes of death was significantly higher in the delirium group than in the no-delirium group although the rate of death at 1 year due to HCC or liver failure was similar between the two groups (p = .015). The 1-year mortality rates due to vascular diseases were 71.4% and 15.4% in the delirium and no-delirium groups, respectively (p = .022). The 1-, 3-, and 5-year survival rates after liver resection were 86.6%, 64.1%, and 36.5% in the delirium group and 91.3%, 71.2%, and 56.9% in the no-delirium group, respectively (p = .046).

CONCLUSION

The multivariate analysis revealed the possible benefits of laparoscopic liver resection in reducing the rate of postoperative delirium after liver resection for HCC in elderly patients.

Influence of Laparoscopic Surgery on Cellular Immunity in Colorectal Cancer: A Systematic Review and Meta-Analysis

Colorectal cancer (CRC) is the third most common cancer worldwide. The main treatment options are laparoscopic (LS) and open surgery (OS), which might differ in their impact on the cellular immunity so indispensable for anti-infectious and antitumor defense. MEDLINE, Embase, Web of Science (SCI-EXPANDED), the Cochrane Library, Google Scholar, ClinicalTrials.gov, and ICTRP (WHO) were systematically searched for randomized controlled trials (RCTs) comparing cellular immunity in CRC patients of any stage between minimally invasive and open surgical resections. A random effects-weighted inverse variance meta-analysis was performed for cell counts of natural killer (NK) cells, white blood cells (WBCs), lymphocytes, CD4+ T cells, and the CD4+/CD8+ ratio. The RoB2 tool was used to assess the risk of bias. The meta-analysis was prospectively registered in PROSPERO (CRD42021264324). A total of 14 trials including 974 participants were assessed. The LS groups showed more favorable outcomes in eight trials, with lower inflammation and less immunosuppression as indicated by higher innate and adaptive cell counts, higher NK cell activity, and higher HLA-DR expression rates compared to OS, with only one study reporting lower WBCs after OS. The meta-analysis yielded significantly higher NK cell counts at postoperative day (POD)4 (weighted mean difference (WMD) 30.80 cells/µL [19.68; 41.92], p < 0.00001) and POD6-8 (WMD 45.08 cells/µL [35.95; 54.21], p < 0.00001). Although further research is required, LS is possibly associated with less suppression of cellular immunity and lower inflammation, indicating better preservation of cellular immunity.

Wound fluid sampling methods for proteomic studies: A scoping review

Understanding why some wounds are hard to heal is important for improving care and developing more effective treatments. The method of sample collection used is an integral step in the research process and thus may affect the results obtained. The primary objective of this study was to summarise and map the methods currently used to sample wound fluid for protein profiling and analysis. Eligible studies were those that used a sampling method to collect wound fluid from any human wound for analysis of proteins. A search for eligible studies was performed using MEDLINE, Embase and CINAHL Plus in May 2020. All references were screened for eligibility by one reviewer, followed by discussion and consensus with a second reviewer. Quantitative data were mapped and visualised using appropriate software and summarised via a narrative summary. After screening, 280 studies were included in this review. The most commonly used group of wound fluid collection methods were vacuum, drainage or use of other external devices, with surgical wounds being the most common sample source. Other frequently used collection methods were extraction from absorbent materials, collection beneath an occlusive dressing and direct collection of wound fluid. This scoping review highlights the variety of methods used for wound fluid collection. Many studies had small sample sizes and short sample collection periods; these weaknesses have hampered the discovery and validation of novel biomarkers. Future research should aim to assess the reproducibility and feasibility of sampling and analytical methods for use in larger longitudinal studies.

Operative Trauma and Blood Loss - Impact on Tumor Growth and Recurrence

ABSTRACT

In cancer patients, surgical removal of the primary tumor is one of the major steps within a multimodal therapy concept toward eliminating the disease and limiting further progression. In this respect, surgical trauma can have potent effects on the patient's immune system. Intraoperative blood loss associated with major surgical trauma leads to reduced blood flow, regional hypoxia, metabolic, and microenvironmental alterations stimulating an inflammatory response characterized by the release of pro-inflammatory cytokines (i.e., TNF-α, IL-6) and acute-phase proteins. The inflammatory state is accompanied by and intertwined with a counter-regulatory anti-inflammatory response reflected in the rise of anti-inflammatory cytokines (i.e., transforming growth factor-β) and prostaglandins (i.e., prostaglandin E2) which can lead to a depression of cell-mediated immunity and systemic immunosuppression. This results in a highly vulnerable state with concurrent expression of pro- and anti-inflammatory cytokines alternately predominating. The immunosuppressive state is characterized by a reduced antigen-presentation capacity of macrophages, alterations in lymphocyte proliferation, and activation as well as a shift of the Th1/Th2 (T helper cells 1 and 2) balance toward Th2 and a decrease in natural killer cell activity. The severity of the immunosuppression thereby correlates with the extent and the duration of the surgical procedure. Growing evidence suggests that the immunosuppressive state following hemorrhage and surgical trauma might not only be a risk factor for postoperative complications but also facilitate tumor proliferation, metastatic growth, and recurrence. This article provides an overview of the cascade of events and underlying mechanisms resulting in immunosuppression and describes the impact of hemorrhage and major surgical trauma on tumor growth and recurrence. Attempts to control for perioperative inflammation thereby reducing the adverse effects of postoperative immunosuppression could have positive effects on tumor growth, metastasis formation, and recurrence.

Premetastatic niches, exosomes and circulating tumor cells: Early mechanisms of tumor dissemination and the relation to surgery

The physiological stress response to surgery promotes wound healing and functional recovery and includes the activation of neural, inflammatory and proangiogenic signaling pathways. Paradoxically, the same pathways also promote metastatic spread and growth of residual cancer. Human and animal studies show that cancer surgery can increase survival, migration and proliferation of residual tumor cells. To secure the survival and growth of disseminated tumor cells, the formation of premetastatic niches in target organs involves a complex interplay between microenvironment, immune system, circulating tumor cells, as well as chemical mediators and exosomes secreted by the primary tumor. This review describes the current understanding of the early mechanisms of dissemination, as well as how surgery may facilitate disease progression.

Plasma and wound fluid levels of eight proangiogenic proteins are elevated after colorectal resection

BACKGROUND

Colorectal resection is associated with 3-5 wk long elevations in the plasma levels of at least 11 proangiogenic proteins that may stimulate tumor angiogenesis post-surgery. The increases during the first week after surgery may be related to the acute inflammatory response; the cause(s) of the week 2-5 increases is unknown. The wounds are a possible source because of the important role that angiogenesis plays in the healing process. The main hypothesis of the study is that wound fluid levels of the proteins studied will be elevated well beyond plasma levels which, in turn, are elevated from preoperative baseline levels.

AIM

To determine plasma and wound fluid levels of 8 proangiogenic proteins after colorectal resection for cancer and benign pathology.

METHODS

Blood and wound fluid samples were taken simultaneously on postoperative (postop) day 1, 3, and later time points until wound drain removal in 35 colorectal cancer patients and 31 benign disease patients undergoing colorectal resection in whom closed wound drains had been placed in either the pelvis or the subcutaneous space of the abdominal incision. Postop plasma levels were compared to preop plasma and postop wound fluid levels (separate analyses for cancer and benign groups).

RESULTS

Sixty-six colorectal disease patients were studied (35 cancer, 31 benign pathology). Most patients underwent minimally invasive surgery (open surgery in 11% of cancer and 6% of benign patients). The majority in the cancer group had rectal resections while in the benign group sigmoid or right colectomy predominated. Plasma levels of all 8 proteins were significantly elevated from baseline (P < 0.05) at all post-operative time points in the cancer group and at 90% of time points (29/32) in the benign group. Wound levels of all 8 proteins were 3-106 times higher (P < 0.05) than plasma levels at 87-90 percent of postop time points; of note, wound levels were more than 10 times higher at 47-50% of time points.

CONCLUSION

Plasma protein levels were elevated for 3 weeks after surgery; wound fluid levels were much greater than corresponding blood levels. Healing wounds may be the source of the plasma increases.

Plasma levels of the proangiogenic protein CXCL16 remains elevated for 1 month after minimally invasive colorectal cancer resection

BACKGROUND

Inflammation-induced endothelial precursor cell recruitment and angiogenesis are thought to be associated with CXCL16-CXCR6 pair activity. This study's main purpose was to determine plasma CXCL16 levels after minimally invasive colorectal resection (MICR) for colorectal cancer (CRC); an adjunct study assessed wound fluid (WF) and plasma CXCL16 levels in a separate group of CRC patients.

METHODS

CRC patients who had MICR and for whom plasma was available in a tissue bank were eligible. Plasma samples were collected preoperatively from all patients. Samples were also collected on postoperative days (POD) 1 and 3 and at various late postoperative time points (POD 7-34). In a separate study, blood and intra-abdominal wound fluid (WF) samples were collected from CRC MICR patients (pts). Samples were stored at - 80 °C. CXCL16 levels were determined via ELISA. The Wilcoxon signed-rank and Mann and Whitney tests were used for analysis.

RESULTS

Main study: 86 CRC pts. were included. The mean preoperative plasma CXCL16 level was 2.36 ± 0.57 ng/ml. Elevated mean plasma levels (p <  0.0001 × first 4 time points) were noted on POD 1 (2.82 ± 0.81, n = 86), POD 3 (3.12 ± 0.77, n = 82), POD 7-13 (3.28 ± 0.88, n = 64), POD 14-20 (3.03 ± 0.62, n = 24), POD 21-27 (3.06 ± 0.67, n = 20, p = 0.0003), and POD 28-34 (3.17 ± 0.43, n = 11, p = 0.001) vs. preop levels. WF study: In the adjunct study, plasma and WF CXCL16 levels were determined for 23 CRC MICR pts. WF levels at all time points were significantly elevated over plasma levels.

CONCLUSION

Plasma CXCL16 levels were elevated for 4 weeks after minimally invasive colorectal resection for cancer. Also, WF CXCL16 levels were 3-10 times greater than the corresponding plasma concentrations. The source of the late plasma elevations may be the healing wound. Increased plasma CXCL16 levels may promote tumor angiogenesis in the first month after MICR.

C-reactive protein in predicting major postoperative complications are there differences in open and minimally invasive colorectal surgery? Substudy from a randomized clinical trial

BACKGROUND

In search of improvement of patient assessment in the postoperative phase, C-reactive protein (CRP) is increasingly being studied as an early marker for postoperative complications following major abdominal surgery. Several studies reported an attenuated immune response in minimally invasive surgery, which might affect interpretation of postoperative CRP levels. The aim of the present study was to compare the value of CRP as a predictor for major postoperative complications in patients undergoing open versus laparoscopic colorectal surgery.

METHODS

A subgroup analysis from a randomized clinical trial (LAFA-trial) was performed, including all patients with non-metastasized colorectal cancer. In the LAFA trial, patients were randomized to open or laparoscopic segmental colectomy. In a subgroup of 79 patients of the LAFA trial, postoperative assessment of CRP levels was conducted routinely preoperatively and 1, 2, 24 and 72 h after surgery.

RESULTS

Thirty-seven patients were randomized to the open group and 42 patients to the laparoscopic group. Major complications occurred in 19% of laparoscopic procedures and 13.5% of open procedures (p = 0.776). CRP levels rise following surgical procedures. In uncomplicated cases, the rise in CRP levels was significantly lower at 24 and 72 h following laparoscopic resection in comparison to open resection. No differences in CRP levels were observed when comparing open and laparoscopic resection in patients with major complications.

CONCLUSION

In patients with an uncomplicated postoperative course, CRP levels were lower following minimally invasive resection, possibly due to decreased operative trauma. No differences in CRP were observed stratified for surgical technique in patients with major complications. These results suggest that CRP may be applied as a marker for major postoperative complications in both open and minimally invasive colorectal surgery. Future research should aim to assess the role of standardized postoperative CRP measurements.

Plasma interleukin-8 levels are persistently elevated for 1 month after minimally invasive colorectal resection for colorectal cancer

Minimally invasive colorectal resection (MICR) for colorectal cancer (CRC) is associated with elevated levels of seven proangiogenic proteins that persist for 2-4 weeks after surgery. The proangiogenic plasma may promote tumor growth postoperatively in patients with residual cancer. To the best of our knowledge, the impact of surgery on interleukin 8 (IL-8) levels is unknown. The aim of the present study was to evaluate plasma IL-8 levels after MICR for CRC. Patients with CRC enrolled in an institutional review board-approved plasma/data bank who underwent MICR were eligible. Blood samples were taken preoperatively (preop) and at multiple postoperative (postop) time points, and were stored at -80°C. Only patients for whom preop, postop day (POD) 1, POD 3 and at least 1 late postop plasma samples (POD7-34) available were enrolled. Clinical, demographical and pathological data were collected. IL-8 levels were determined via ELISA and results were reported as the mean and ± standard deviation. The Wilcoxon signed rank test was used for analysis with P<0.05 used as the significance threshold. A total of 73 CRC patients (colon, 62%; rectal, 38%) who underwent MICR (laparoscopic-assisted, 60%; hand-assisted, 40%) were studied. The mean preop IL-8 level was 20.4±10.6 pg/ml. Significant elevations in plasma IL-8 levels were noted compared with preop levels on POD1 (43.1±38.6; n=72; P<0.0001), POD 3 (33.0±30.1; n=71; P<0.0001), POD7-13 (29.9±21.9; n=50; P<0.0001), POD14-20 (33.1±18.3; n=24; P=0.002), and for the POD21-27 time point (24.0±9.2; n=16; P=0.002). In conclusion, plasma IL-8 levels were significantly elevated from baseline for 4 weeks after MICR for CRC. In conjunction with the other proangiogenic MICR-associated blood compositional changes, increased IL-8 levels may promote tumor angiogenesis and growth postop.

Postoperative serum Vascular Endothelial Growth Factor is an independent prognostic factor of disease free survival and overall survival in patients with non metastatic colon cancer

BACKGROUND

Angiogenesis is essential for tumor growth and formation of metastasis. VEGF is the most potent agiogenic citokine. The aim was to investigate the predictive value of postoperative VEGF serum concentration in patients undergoing surgery for colon cancer.

METHODS

Consecutive patients with colon cancer undergoing surgery with curative intent were included. VEGF was measured in serum at 48 h and postoperative day 4. Cox proportional hazards model was used to estimate its contribution with prognosis.

RESULTS

A total of 94 patients were included. On multivariate analysis VEGF on postoperative day 4 (HR: 1.05; p = 0.011) was independent prognostic factor of decreased DFS and OS. Five-year DFS (57.7% vs. 85%; p = 0.001) and OS (93% vs. 72%; p = 0.005) were significantly lower in patients with postoperative serum VEGF greater than 370 pg/dl.

CONCLUSION

Postoperative VEGF serum concentration was an independent predictor of recurrence. These results must be verified in a prospective independent testing cohort.

Monitoring of Serum Levels of Angiogenin, ENA-78 and GRO Chemokines in Patients with Renal Cell Carcinoma (RCC) in the Course of the Treatment

Tumour progression requires the presence of a rich vascular supply. A number of cytokines, chemokines and proteases participate in the process of tumour angiogenesis. We evaluated serum levels of angiogenin, panGRO (Growth Related Oncogene) (CXCL 1,2,3) and ENA-78 (Epithelial Neutrophil Activating) (CXCL5) in the serum of 32 patients with RCC (renal cell carcinoma) and 14 healthy blood donors by means of a protein array analysis. The patients were divided into three groups according to their disease stages (I+II, III, IV). We discovered significant differences between the blood donors and patients with RCC both in pre-operative and post-operative angiogenin, panGRO and ENA-78 levels. The increase in angiogenic factors lasted in patients even without metastases 2 months after surgery. We found no correlation between the levels of angiogenin and stages I+II, III and IV RCC. Patients with advanced carcinoma (stage III) had pre-operatively higher serum levels of ENA-78 than patients with stages I+II (p = 0,009) and IV (p< 0.001). Eight weeks after surgery the patients with stages I+II had significantly higher levels of panGRO than patients with stage IV.

Plasma chitinase 3-like 1 is persistently elevated during first month after minimally invasive colorectal cancer resection

AIM: To assess blood chitinase 3-like 1 (CHi3L1) levels for 2 mo after minimally invasive colorectal resection (MICR) for colorectal cancer (CRC).

METHODS: CRC patients in an Institutional Review Board approved data/plasma bank who underwent elective MICR for whom preoperative (PreOp), early postoperative (PostOp), and 1 or more late PostOp samples [postoperative day (POD) 7-27] available were included. Plasma CHi3L1 levels (ng/mL) were determined in duplicate by enzyme linked immunosorbent assay.

RESULTS: PreOp and PostOp plasma sample were available for 80 MICR cancer patients for the study. The median PreOp CHi3L1 level was 56.8 CI: 41.9-78.6 ng/mL (n = 80). Significantly elevated (P < 0.001) median plasma levels (ng/mL) over PreOp levels were detected on POD1 (667.7 CI: 495.7, 771.7; n = 79), POD 3 (132.6 CI: 95.5, 173.7; n = 76), POD7-13 (96.4 CI: 67.7, 136.9; n = 62), POD14-20 (101.4 CI: 80.7, 287.4; n = 22), and POD 21-27 (98.1 CI: 66.8, 137.4; n = 20, P = 0.001). No significant difference in plasma levels were noted on POD27-41.

CONCLUSION: Plasma CHi3L1 levels were significantly elevated for one month after MICR. Persistently elevated plasma CHi3L1 may support the growth of residual tumor and metastasis.

Minimally invasive colorectal resection is associated with significantly elevated levels of plasma matrix metalloproteinase 3 (MMP-3) during the first month after surgery which may promote the growth of residual metastases

INTRODUCTION

MMP-3, a member of the matrix metalloproteinase (MMP) family, is involved in the breakdown of the extracellular matrix in tissue remodeling and may also play a role in cancer progression and metastasis. Minimally invasive colorectal resection (MICR) may increase plasma MMP-3 levels directly via surgical trauma or indirectly due to surgery-associated elevations in TNF-α and IL1 which are regulators of MMP-3. This study's purpose was to evaluate plasma MMP-3 levels during the first month after MICR for colorectal cancer.

METHODS

Patients enrolled in an IRB approved data/plasma bank who underwent elective MICR for CRC. Blood plasma samples had been collected preoperatively, on postoperative day (POD) 1, 3 and at varying postoperative time points and were stored at -80 °C. The late samples (POD 7-41) were bundled into 7 day time blocks and considered as single time points. MMP-3 levels were analyzed in duplicate via ELISA and the results reported as mean ± SD. The paired t test was used for analysis (significance, p < 0.008 after Bonferroni's correction).

RESULTS

A total of 73 CRC patients who underwent MICR met the inclusion criteria. The mean PreOp MMP-3 level was 14.9 ± 7.8 ng/ml (n = 73). Significantly elevated mean plasma levels were noted on POD 1 (21.4 ± 14.7 ng/ml, n = 73, p < 0.0001), POD 3 (37.9 ± 21.5 ng/ml, n = 72, p < 0.0001), POD 7-13 (22.0 ± 13.0 ng/ml, n = 56, p < 0.0001), POD 14-20 (21.9 ± 10.3 ng/ml, n = 20, p = 0.003), and on POD 21-27 (21.9 ± 11.43 ng/ml, n = 20, p = 0.002) when compared to PreOp levels. Plasma levels returned to the PreOp baseline at the POD 28-41 time point (n = 16, p = 0.07).

CONCLUSION

Plasma MMP-3 levels remained significantly elevated from baseline for 4 weeks after MICR for CRC. The early postoperative increase in MMP-3 levels may be due to the surgery-related acute inflammatory response; the elevation noted during weeks 2-3 may be related to wound healing. Increased MMP-3 levels may promote metastases or the growth of residual cancer.

Minimally invasive colorectal resection for benign pathology is associated with persistent proangiogenic plasma compositional changes

BACKGROUND

Minimally invasive colorectal resection for cancer is associated with increased plasma levels of numerous proangiogenic proteins for 3 to 4 weeks postoperatively, and plasma from postoperative weeks 2 and 3 stimulates proangiogenic endothelial cell behavior in vitro. It is unknown if similar plasma changes occur after minimally invasive colorectal resection for benign pathology.

OBJECTIVE

The aim of this study is to assess 1) plasma levels of angiopoetin-2, placental growth factor, and soluble vascular cell adhesion molecule-1 after minimally invasive colorectal resection for benign pathology and 2) postoperative plasma's effects on in vitro endothelial cell proliferation (branch point formation), migration, and invasion.

DESIGN

Prospectively gathered plasma samples taken from patients undergoing colorectal resection who consented to participate in an institutional review board-approved plasma and data bank were used for ELISAs and in vitro endothelial cell studies.

SETTINGS

The plasma and clinical data used were collected at 3 hospitals.

PATIENTS

Patients undergoing minimally invasive colorectal resection for benign indications who were enrolled in a plasma/data bank and for whom adequate samples and volumes of plasma were available were included in the study.

MAIN OUTCOME MEASURES

Perioperative plasma levels of angiopoetin-2, placental growth factor, and soluble vascular cell adhesion molecule-1 were the primary outcomes measured. In vitro rates of endothelial cell branch point formation, migration, and invasion were determined after the addition of preoperative and postoperative plasma samples to endothelial cell cultures.

RESULTS

Plasma from 86 patients undergoing minimally invasive colorectal resection for benign indications was assessed (diverticulitis, 30; benign polyps, 56). Plasma levels of angiopoetin-2, placental growth factor, and soluble vascular cell adhesion molecule-1 were significantly increased for 3 to 4 weeks postoperatively compared with preoperative levels. In regard to the endothelial cell culture assays, significantly increased endothelial cell branch point formation, invasion, and migration results were noted with plasma from the second and third weeks postoperatively in comparison with preoperative culture results.

LIMITATIONS

The weaknesses of this study are the limited numbers of late postoperative plasma samples and the need to bundle late samples into 7- to 12-day time blocks.

CONCLUSIONS

Minimally invasive colorectal resection for benign pathology is associated with persistent proangiogenic plasma alterations similar to those found in patients who have cancer. Surgical trauma and not the indication is the likely cause.

The estimation of metaloproteinases and their inhibitors blood levels in patients with pancreatic tumors

Background

The aim of the study was to evaluate the concentration of proteolytic enzymes, MMP-2 and MMP-9, and their tissue inhibitors, TIMP-1 and TIMP-2, in the blood of patients with benign and malignant pancreatic tumors.

Methods

MMP-2, MMP-9, TIMP-1, and TIMP-2 were evaluated in the patients with benign and malignant pancreatic tumors before surgery and in the 30-day follow-up. The study covered 134 patients aged 54 to 76 years, who were divided into groups by TNM staging.

Results

Before the operation, the highest mean concentration of MMP-2 was found in patients with unresectable cancer, whereas the highest level of MMP-9 was in patients with resectable cancer. The highest level of TIMP-1 was noted in patients with inflammatory tumors. In 1 month following the operation, the highest level of MMP-2 was also in patients with unresectable cancer and the highest level of TIMP-2 in patients with inflammatory tumors.

Conclusions

The evaluation of the level of the studied cytokines in the pancreatic tumor patients can be diagnostically significant in the differentiation of benign and malignant changes. The changes in the levels of the studied enzymes and their inhibitors can have a prognostic value in the clinical severity of pancreatic cancer.

A prospective case-control study of the local and systemic cytokine response after laparoscopic versus open colonic surgery

BACKGROUND

There is a sequential, high concentration cytokine response after major abdominal surgery. The magnitude of this response has been directly linked to postoperative metabolic derangement, ileus, adhesions, and oncological outcomes. We aimed to compare the local and systemic cytokine response in laparoscopic and open colonic surgery and relate this to postoperative recovery parameters.

METHODS

Using a prospectively collected patient database, we compared a Study Group (n = 50) of patients undergoing elective laparoscopic colonic resection with a Control Group (n = 25) of patients undergoing equivalent open colonic surgery within an ERAS program. Patients were matched for age, gender, BMI, ASA, Cr Possum, side of resection, diagnosis, and histologic stage. Plasma and peritoneal fluid concentrations of IL-6, IL-8, IL-10, and TNFα were measured at 20-24 h after surgery. The Surgical Recovery Score was determined pre-operatively and at 3, 7, 30, and 60 d postoperatively. All data were prospectively collected, and a priori definitions were used for discharge parameters, complications, and complication severity.

RESULTS

Peritoneal fluid IL-6 concentration was lower after laparoscopic surgery. There were no significant differences in the other cytokines measured, or in any postoperative recovery outcomes. Significant correlations were found between cytokine levels and discharge criteria achievement, day stay, postoperative complications, and the Surgical Recovery Score.

CONCLUSION

With the exception of a lower peritoneal IL-6 level, the systemic and peritoneal cytokine response at 20-24 h is similar after laparoscopic versus open colonic resection within an ERAS program, with corresponding equivalent rates of postoperative recovery.

Randomized clinical trial comparing inflammatory and angiogenic response after open versus laparoscopic curative resection for colonic cancer

BACKGROUND

Several studies have suggested that laparoscopy might confer an oncological advantage in patients undergoing surgery for colonic cancer. A decreased inflammatory and angiogenic response has been proposed. This study compared the local and systemic inflammatory and angiogenic responses after open and laparoscopic surgery for colonic cancer.

METHODS

Some 122 patients with colonic cancer were randomized to open or laparoscopic colectomy. Levels of interleukin (IL) 6 and vascular endothelial growth factor (VEGF) were measured in serum and peritoneal fluid at baseline, then at 4, 12, 24 and 48 h and on day 4 after surgery. Samples obtained on day 4 were tested in an in vitro angiogenesis assay, with measurement of number of capillaries per field and capillary length.

RESULTS

The serum IL-6 level was lower in the laparoscopic group at 4 h (mean(s.d.) 124(110) versus 244(326) pg/dl after open colectomy; P = 0·027). The serum VEGF concentration was also lower in the laparoscopic group at 48 h and day 4 (430(435) versus 650(686) pg/dl; P = 0·001). Overall, local IL-6 and VEGF levels were significantly higher than serum levels but there were no differences between groups. In vitro, postoperative serum and peritoneal fluid samples were potently angiogenic but there were no differences between open surgery and laparoscopy. Rates of tumour recurrence and survival were similar in the two groups.

CONCLUSION

Despite differences in postoperative serum levels of IL-6 and VEGF after open and laparoscopic surgery in patients with colonic cancer, the angiogenic response is comparable in both surgical approaches.

REGISTRATION NUMBER

ISRCTN55624793 (http://www.controlled-trials.com).

The humoral response after laparoscopic versus open colorectal surgery: a meta-analysis

BACKGROUND

The local and systemic humoral response after colorectal surgery is thought to affect postoperative recovery. It is commonly claimed that laparoscopic surgery elicits a diminished inflammatory response than equivalent open surgery. Despite these claims, the evidence is conflicting. Therefore, we aimed to systematically review the results from randomized controlled clinical trials comparing the humoral response associated with laparoscopic versus open colorectal surgery.

MATERIALS AND METHODS

A high-sensitivity search was conducted independently by two of the authors with no language restriction. Studies were identified from the Cochrane Central Register of Controlled Trials (CENTRAL/CCTR), Cochrane Library, Medline (January 1966 to January 2009), PubMed (1950 to January 2009), and Embase (1947 to January 2009). Relevant meeting abstracts and reference lists were manually searched. Data analysis was performed using Review Manager ver. 5.0.

RESULTS

Thirteen randomized controlled trials were included. Meta-analysis demonstrated a significantly higher serum IL-6 on d 1 after open colorectal resection for neoplasia (n = 97) compared with laparoscopic resection (n = 76, P = 0.0008) without significant heterogeneity. Data for plasma IL-6 were heterogeneous, with no apparent difference between groups. No other significant differences were identified, and there were not enough data on local peritoneal humoral factors to allow meta-analysis.

CONCLUSION

Open colorectal resection for neoplasia is associated with higher postoperative serum levels of IL-6 on d 1 than equivalent laparoscopic surgery. The aetiology and clinical significance of this finding is uncertain, and further studies are required to elucidate any differences in the local humoral response which may be more clinically relevant in surgery for this indication.

Preoperative serum vascular endothelial growth factor-a is a marker for subsequent recurrence in colorectal cancer patients

PURPOSE

Serum vascular endothelial growth factor-A has been associated with stage of disease and prognosis in colorectal cancer. In this study, the clinical usefulness of preoperative serum vascular endothelial growth factor-A concentrations in the long-term follow-up of colorectal cancer patients was evaluated.

METHODS

Serum vascular endothelial growth factor-A levels were determined by quantitative enzyme-linked immunosorbent assay in 93 patients prior to resection for colorectal cancer: node-negative (n = 41) and node-positive (n = 52). Median follow-up for patients without cancer death was 54 (interquartile range, 24-63.5) months.

RESULTS

The median preoperative serum vascular endothelial growth factor-A level of these patients was 168 (interquartile range, 48-414) pg/ml. Seven patients had local recurrences with a median time of 6 (interquartile range, 4-12) months. Patients (n = 17) that developed metastasis had a median time of 17 (interquartile range, 7-42) months. Patients with local recurrence had significantly higher levels of serum vascular endothelial growth factor-A (P = 0.01). By classifying the patients into two groups, using the maximal chi-squared value of the Cox's regression based on our previous work, it was found that a serum vascular endothelial growth factor-A level >575 pg/ml is an independent prognostic factor for predicting tumor recurrence.

CONCLUSION

Patients with colorectal cancer who have preoperative serum vascular endothelial growth factor-A levels >575 pg/ml are more likely to develop recurrence. Trials are warranted to investigate the efficacy of adjuvant therapy for this high-risk group.

Colorectal resection, both open and laparoscopic-assisted, in patients with benign indications is associated with proangiogenic changes in plasma angiopoietin 1 and 2 levels

INTRODUCTION

Plasma vascular endothelial growth factor (VEGF) levels are increased after surgery and may stimulate tumor growth after cancer resection. Angiopoietin 1 (Ang 1) and Ang 2 are proteins that impact VEGF-related angiogenesis (VRA). Ang 1 stabilizes mature vessels and inhibits VRA, whereas Ang 2 destabilizes vessels and promotes VRA. The ratio of Ang 1 to Ang 2 reflects the net effect; a low ratio promotes VRA. This study's purpose was to determine the impact of open and minimally invasive (MIS) colorectal resection (CR) for benign indications on plasma Ang 1 and 2 levels.

METHODS

A total of 30 patients operated by MIS and 26 operated by open procedure were studied. Plasma was obtained preoperatively (PO) and on postoperative days (POD) 1 and 3. Plasma Ang 1 and Ang 2 levels were assessed via enzyme-linked immunosorbent assay (ELISA) in duplicate. Data were compared using Wilcoxon's matched-pair test and the Mann-Whitney U-test (significance p < 0.05).

RESULTS

Indications, types of resection, and morbidity for the groups were similar. The mean MIS incision length was 4.7 +/- 1.6 cm while it was 16.8 +/- 7.1 cm for the open group (p = 0.0001). For both groups Ang 2 levels were significantly higher and the Ang 1 to Ang 2 ratio was significantly lower on POD 1 and 3 compared with preoperative results. Ang 1 levels were significantly decreased on POD 1 and 3 in the MIS group but only on POD 1 in the open group. For unclear reasons, preoperative Ang 1 levels and Ang 1 to Ang 2 ratios were significantly different between the groups, which precludes comparison of the postoperative results between groups.

CONCLUSION

CR for benign pathology results in higher Ang 2 levels, lower Ang 1 levels, and lower Ang 1 to Ang 2 ratios early after surgery. These alterations are proangiogenic. These results, plus the already noted VEGF increases, suggest that surgery results in proangiogenic plasma protein changes that may stimulate tumor growth early after surgery. The duration of the Ang 1 and 2 changes needs to be determined.

Long-term results of laparoscopic colorectal cancer resection

BACKGROUND

Although minimally invasive surgery has been accepted for a variety of disorders, laparoscopic resection of colorectal cancer is performed by few. Concern about oncological radicality and long term outcome has limited the adoption of laparoscopic surgery for colorectal cancer.

OBJECTIVES

To determine long-term outcome after laparoscopically-assisted versus open surgery for non-metastasised colorectal cancer.

SEARCH STRATEGY

The Cochrane library, EMBASE, Pub med and Cancer Lit were searched for published and unpublished randomised controlled trials.

SELECTION CRITERIA

Randomised clinical trials comparing laparoscopically-assisted and open surgery for non-metastasised colorectal cancer were included. Studies that did not report any long-term outcomes were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed the studies and extracted data. RevMan 4.2 was used for statistical analysis.

MAIN RESULTS

Thirty-three randomised clinical trials (RCT) comparing laparoscopically-assisted versus open surgery for colorectal cancer were identified. Twelve of these trials, involving 3346 patients, reported long-term outcome and were included in the current analysis. No significant differences in the occurrence of incisional hernia, reoperations for incisional hernia or reoperations for adhesions were found between laparoscopically assisted and open surgery (2 RCT, 474 pts, 7.9% vs 10.9%;P = 0.32 and 2 RCT, 474 pts, 4.0% vs 2.8%; P = 0.42 and 1 RCT, 391 pts, 1.1% vs 2.5%;P = 0.30, respectively). Rates of recurrence at the site of the primary tumor were similar (colon cancer: 4 RCT, 938 pts, 5.2% vs 5.6%; OR (fixed) 0.84 (95% CI 0.47 to 1.52)(P = 0.57); rectal cancer: 4 RCT, 714 pts, 7.2% vs 7.7%; OR (fixed) 0.81 (95% CI 0.45 to 1.43) (P = 0.46). No differences in the occurrence of port-site/wound recurrences were observed (P=0.16). Similar cancer-related mortality was found after laparoscopic surgery compared to open surgery ( colon cancer: 5 RCT, 1575 pts, 14.6% vs 16.4%; OR (fixed) 0.80 (95% CI 0.61 to 1.06) (P=0.15); rectal cancer: 3 RCT, 578 pts, 9.2% vs 10.0%; OR (fixed) 0.66 (95% CI 0.37 to 1.19) (P=0.16). Four studies were included in the meta-analyses on hazard ratios for tumour recurrence in laparoscopic colorectal cancer surgery. No significant difference in recurrence rate was observed between laparoscopic and open surgery (hazard ratio for tumour recurrence in the laparoscopic group 0.92; 95% CI 0.76-1.13). No significant difference in tumour recurrence between laparoscopic and open surgery for colon cancer was observed (hazard ratio for tumour recurrence in the laparoscopic group 0.86; 95% CI 0.70-1.08).

AUTHORS' CONCLUSIONS

Laparoscopic resection of carcinoma of the colon is associated with a long term outcome no different from that of open colectomy. Further studies are required to determine whether the incidence of incisional hernias and adhesions is affected by method of approach. Laparoscopic surgery for cancer of the upper rectum is feasible, but more randomised trials need to be conducted to assess long term outcome.

Long-term results of laparoscopic colorectal cancer resection

BACKGROUND

Although minimally invasive surgery has been accepted for a variety of disorders, laparoscopic resection of colorectal cancer is performed by few. Concern about oncological radicality and long term outcome has limited the adoption of laparoscopic surgery for colorectal cancer.

OBJECTIVES

To determine long-term outcome after laparoscopically-assisted versus open surgery for non-metastasised colorectal cancer.

SEARCH STRATEGY

The Cochrane library, EMBASE, Pub med and Cancer Lit were searched for published and unpublished randomised controlled trials.

SELECTION CRITERIA

Randomised clinical trials comparing laparoscopically-assisted and open surgery for non-metastasised colorectal cancer were included. Studies that did not report any long-term outcomes were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed the studies and extracted data. RevMan 4.2 was used for statistical analysis.

MAIN RESULTS

Thirty-three randomised clinical trials (RCT) comparing laparoscopically-assisted versus open surgery for colorectal cancer were identified. Twelve of these trials, involving 3346 patients, reported long-term outcome and were included in the current analysis. No significant differences in the occurrence of incisional hernia, reoperations for incisional hernia or reoperations for adhesions were found between laparoscopically assisted and open surgery (2 RCT, 474 pts, 7.9% vs 10.9%;P = 0.32 and 2 RCT, 474 pts, 4.0% vs 2.8%; P = 0.42 and 1 RCT, 391 pts, 1.1% vs 2.5%;P = 0.30, respectively). Rates of recurrence at the site of the primary tumor were similar (colon cancer: 4 RCT, 938 pts, 5.2% vs 5.6%; OR (fixed) 0.84 (95% CI 0.47 to 1.52)(P = 0.57); rectal cancer: 4 RCT, 714 pts, 7.2% vs 7.7%; OR (fixed) 0.81 (95% CI 0.45 to 1.43) (P = 0.46). No differences in the occurrence of port-site/wound recurrences were observed (P=0.16). Similar cancer-related mortality was found after laparoscopic surgery compared to open surgery ( colon cancer: 5 RCT, 1575 pts, 14.6% vs 16.4%; OR (fixed) 0.80 (95% CI 0.61 to 1.06) (P=0.15); rectal cancer: 3 RCT, 578 pts, 9.2% vs 10.0%; OR (fixed) 0.66 (95% CI 0.37 to 1.19) (P=0.16). Four studies were included in the meta-analyses on hazard ratios for tumour recurrence in laparoscopic colorectal cancer surgery. No significant difference in recurrence rate was observed between laparoscopic and open surgery (hazard ratio for tumour recurrence in the laparoscopic group 0.92; 95% CI 0.76-1.13). No significant difference in tumour recurrence between laparoscopic and open surgery for colon cancer was observed (hazard ratio for tumour recurrence in the laparoscopic group 0.86; 95% CI 0.70-1.08).

AUTHORS' CONCLUSIONS

Laparoscopic resection of carcinoma of the colon is associated with a long term outcome no different from that of open colectomy. Further studies are required to determine whether the incidence of incisional hernias and adhesions is affected by method of approach. Laparoscopic surgery for cancer of the upper rectum is feasible, but more randomised trials need to be conducted to assess long term outcome.

Persistent elevation of plasma vascular endothelial growth factor levels during the first month after minimally invasive colorectal resection

BACKGROUND

Elevations of plasma vascular endothelial growth factor (VEGF) have been noted early after colorectal resection. The duration of this increase is unknown. Because VEGF is a potent promoter of angiogenesis, which is critical to tumor growth, a sustained increase in blood VEGF levels after surgery may stimulate the growth of residual metastases early after surgery. This preliminary study aimed to determine VEGF levels during the first month after colorectal resection.

METHODS

Patients from three prospective studies that had late postoperative blood samples available comprised the study population. Demographic, perioperative, pathologic, and complication data were collected. Plasma samples were obtained preoperatively for all patients: on postoperative day (POD) 1 for most patients and at varying time points thereafter during the first month after surgery and beyond. Levels of VEGF were determined via enzyme-linked immunoassay (ELISA) and compared using Wilcoxon's matched pairs test. Because the numbers of specimens beyond POD 5 were limited, samples from 7-day time blocks were bundled and averaged to permit statistical analysis.

RESULTS

A total of 49 patients with cancer and 30 patients with benign indications, all of whom underwent minimally invasive colorectal resection, were assessed separately. With regard to the patients with cancer, the median preoperative plasma value was 150 pg/ml, and the peak postoperative median value for the POD 14 to 20 time block was 611.1 pg/ml. Furthermore, compared with the preoperative results, significant VEGF elevations were noted on POD 3 as well as during week 2 (POD 7-13), week 3 (POD 14-20), and week 4 (POD 21-27) (p < 0.05 for each). With regard to the benign patients, the median preoperative VEGF level was 112 pg/ml, and the peak postoperative value, 286 pg/ml, was noted during postoperative week 2. Significant elevations were noted on POD 3, and for weeks 2 and 3 as well as for POD 28 and later. Between 63% and 89% of the patients at each time point beyond POD 5 had elevated VEGF levels.

CONCLUSION

This preliminary study demonstrates that after minimally invasive colorectal resection for cancer, median VEGF levels are significantly elevated on POD 3 and remain increased for as long as 4 weeks. Significant elevations in a similar pattern also were noted for the benign patients. However, the baseline and postoperative median values were lower. The clinical impact from increased blood levels of VEGF is uncertain. It is possible that the growth of residual tumor deposits may be stimulated early after surgery. These results warrant a larger study as well as endothelial cell in vitro assays to determine whether postoperative plasma stimulates proliferation and invasion.

Angiogenesis inhibition with bevacizumab and the surgical management of colorectal cancer

BACKGROUND

Bevacizumab is an angiogenesis inhibitor and a new therapy for the treatment of colorectal cancer. It is a humanized monoclonal antibody that targets vascular endothelial growth factor.

METHODS

This review is based on a literature search of Medline, Pubmed, ISI web of knowledge and other published work for original articles, reviews and abstracts relevant to the surgical management of colorectal cancer with bevacizumab.

RESULTS AND CONCLUSION

Combined with current chemotherapy regimens, bevacizumab offers a significant survival advantage, making it likely to see widespread use. Despite being generally well tolerated, serious toxicities, including wound complications and gastrointestinal perforation, have been reported that affect surgical management. Consideration should be given to the timing of surgical and adjuvant intervention when using this drug.

Systematic review on the short-term outcome of laparoscopic resection for colon and rectosigmoid cancer

OBJECTIVE

Several large randomized controlled trials on laparoscopic resection for colon and rectosigmoid cancer have recently been published. There is a need to provide an up-to-date systematic review in this subject.

METHODS

A literature search of all published randomized trials in English between January 1991 and September 2005 was obtained, from Ovid MEDLINE, EMBASE, CINAHL, and All EBM Reviews (Cochrane Central Register of Controlled Trial, Cochrane Database of Systemic Review, and Database of Abstracts of Reviews of Effects), including e-links to the related articles. Two independent assessors reviewed the trials using a standardized protocol. Where means and standard deviations were available, meta-analysis was performed using the Forest plot review. Studies where medians and ranges were presented were separately analysed.

RESULTS

A total of 17 randomized controlled trials with 4013 procedures were reviewed. The conversion rate varied widely between studies and was lowest in single-Centre trials. There were no significant differences in overall and surgical complication rate, anastomotic leak rate, re-operation rate and oncological clearance. However, laparoscopic resection has a significantly lower peri-operative mortality (odds ratio 0.33; P = 0.005), lower wound complications (odds ratio 0.65; P = 0.01), less blood loss (weighted mean difference 0.11 l; P < 0.00001) and reduced postoperative pain scores by 12.6% with reduction of requirements for narcotic analgesia by 30.7%. After laparoscopic surgery, patients passed flatus 38.8% earlier (weighted mean difference 27.6 h; P < 0.00001) and had bowel movement 21.0% earlier (weighted mean difference 23.9 h; P < 0.00001) and resumed oral diet 28.3% sooner than patients in the open group (weighted mean difference 27.3 h; P < 0.00001). Patients were discharged 19.1% earlier after laparoscopic surgery than open surgery (weighted mean difference 1.7 days; P < 0.00001). Laparoscopic resection took 28.7% longer (weighted mean difference 40.1 min; P < 0.00001) to perform.

CONCLUSIONS

Laparoscopic resection for colon and rectosigmoid cancer is feasible, safe and has many short-term benefits.

Length of laparotomy incision and surgical stress assessed by serum IL-6 level

BACKGROUND

Because surgical stress is thought to have an effect on morbidity, mortality, and remnant tumour progression after surgery, diminishing surgical stress is important. The purpose of this study was to assess in a murine model whether the length and type of laparotomy incision influence surgical stress.

METHODS

Serum IL-6 concentrations were measured sequentionally in 220 male BALB/c mice who were assigned to different basic laparotomies, (1-cm versus 2-cm versus 3-cm laparotomy with or without caecal resection), other types of laparotomy (3-cm, 1-cm x 3, 3-cm transverse, 3-cm laparotomy with rapid closure), or 3-cm skin incision with or without laparotomy. The serum level of IL-6 was measured by ELISA.

RESULTS

Serum IL-6 levels at 3 and 6h after surgery were significantly higher in the 3-cm laparotomy group (1,680+/-802pg/ml and 1,066+/-507pg/ml, respectively), than in the 1-cm laparotomy group (797+/-427pg/ml and 515+/-212pg/ml, respectively). When caecal resection was added, the serum IL-6 level at 6h was significantly higher in the 3-cm laparotomy group (2,844+/-134pg/ml) than in the 1-cm laparotomy group (2,200+/-379pg/ml). Although the type of laparotomy incision was not associated with the serum level of IL-6, the serum IL-6 level after midline skin incision without laparotomy (245+/-142pg/ml) was significantly lower than that after 3-cm laparotomy (1,680+/-802pg/ml).

CONCLUSIONS

The length of laparotomy incision was correlated with the serum level of IL-6 in a murine model. The surgical stress related to abdominal procedures might be decreased when laparotomy wounds are kept as small as possible.