Eureka: objective assessment of the empty pelvis syndrome to measure volumetric changes in pelvic dead space following pelvic exenteration.

BACKGROUND: Large tissue defects following pelvic exenteration (PE) fill with fluid and small bowel, leading to the empty pelvis syndrome (EPS). EPS causes a constellation of complications including pelvic sepsis and reduced quality of life. EPS remains poorly defined and cannot be objectively measured. Pathophysiology of EPS is multifactorial, with increased pelvic dead space potentially important. This study aims to describe methodology to objectively measure volumetric changes relating to EPS. METHODS: The true pelvis is defined by the pelvic inlet and outlet. Within the true pelvis there is physiological pelvic dead space (PDS) between the peritoneal reflection and the inlet. This dead space is increased following PE and is defined as the exenteration pelvic dead space (EPD). EPD may be reduced with pelvic filling and the volume of filling is defined as the pelvic filling volume (PFV). PDS, EPD, and PFV were measured intraoperatively using a bladder syringe, and Archimedes' water displacement principle. RESULTS: A patient undergoing total infralevator PE had a PDS of 50 ml. A rectus flap rendered the pelvic outlet watertight. EPD was then measured as 540 ml. Therefore there was a 10.8-fold increase in true pelvis dead space. An omentoplasty was placed into the EPD, displacing 130 ml; therefore, PFV as a percentage of EPD was 24.1%. CONCLUSIONS: This is the first reported quantitative assessment of pathophysiological volumetric changes of pelvic dead space; these measurements may correlate to severity of EPS. PDS, EPD, and PFV should be amendable to assessment based on perioperative cross-sectional imaging, allowing for potential prediction of EPS-related outcomes.

A minimum core outcome dataset for the reporting of preclinical chemotherapeutic drug studies: Lessons learned from multiple discordant methodologies in the setting of colorectal cancer.

In vivo studies in animal models are critical tools necessary to study the fundamental complexity of carcinogenesis. A constant strive to improve animal models in cancer exists, especially those investigating the use of chemotherapeutic effectiveness. In the present systematic review, colorectal cancer (CRC) is used as an example to highlight and critically evaluate the range of reporting strategies used when investigating chemotherapeutic agents in the preclinical setting. A systematic review examining the methodology and reporting of preclinical chemotherapeutic drug studies using CRC murine models was conducted. A total of 45 studies were included in this systematic review. The literature was found to be highly heterogeneous with various cell lines, animal strains, animal ages and chemotherapeutic compounds/regimens tested, proving difficult to compare outcomes between similar studies or indeed gain any significant insight into which chemotherapeutic regimen caused adverse events. From this analysis we propose a minimum core outcome dataset that could be regarded as a standardised way of reporting results from in vivo experimentation.

Translational aspects in targeting the stromal tumour microenvironment: from bench to bedside.

Solid tumours comprise, not only malignant cells but also a variety of stromal cells and extracellular matrix proteins. These components interact via an array of signalling pathways to create an adaptable network that may act to promote or suppress cancer progression. To date, the majority of anti-tumour chemotherapeutic agents have principally sought to target the cancer cell. Consequently, resistance develops because of clonal evolution, as a result of selection pressure during tumour expansion. The concept of activating or inhibiting other cell types within the tumour microenvironment is relatively novel and has the advantage of targeting cells which are genetically stable and less likely to develop resistance. This review outlines key players in the stromal tumour microenvironment and discusses potential targeting strategies that may offer therapeutic benefit.

miR-19-Mediated Inhibition of Transglutaminase-2 Leads to Enhanced Invasion and Metastasis in Colorectal Cancer.

UNLABELLED: Transglutaminase-2 (TG2) is a critical cross-linking enzyme in the extracellular matrix (ECM) and tumor microenvironment (TME). Although its expression has been linked to colorectal cancer, its functional role in the processes that drive disease appears to be context dependent. There is now considerable evidence of a role for microRNAs (miRNA) in the development and progression of cancer, including metastasis. A cell model of metastatic colon adenocarcinoma was used to investigate the contribution of miRNAs to the differential expression of TG2, and functional effects on inflammatory and invasive behavior. The impact of TG2 in colorectal cancer was analyzed in human colorectal tumor specimens and by manipulations in SW480 and SW620 cells. Effects on invasive behavior were measured using Transwell invasion assays, and cytokine production was assessed by ELISA. TG2 was identified as a target for miR-19 by in silico analysis, which was confirmed experimentally. Functional effects were evaluated by overexpression of pre-miR-19a in SW480 cells. Expression of TG2 correlated inversely with invasive behavior, with knockdown in SW480 cells leading to enhanced invasion, and overexpression in SW620 cells the opposite. TG2 expression was observed in colorectal cancer primary tumors but lost in liver metastases. Finally, miR-19 overexpression and subsequent decreased TG2 expression was linked to chromosome-13 amplification events, leading to altered invasive behavior in colorectal cancer cells. IMPLICATIONS: Chromosome-13 amplification in advanced colorectal cancer contributes to invasion and metastasis by upregulating miR-19, which targets TG2.

Cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy improves survival in patients with colorectal peritoneal metastases compared with systemic chemotherapy alone.

BACKGROUND: Colorectal cancer peritoneal metastasis (CPM) confers an exceptionally poor prognosis, and traditional treatment involving systemic chemotherapy (SC) is largely ineffective. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is increasingly advocated for selected patients with CPM; however, opinions are divided because of the perceived lack of evidence, high morbidity, mortality, and associated costs for this approach. As there is no clear consensus, the aim of this study was to compare outcomes following CRS+HIPEC vs SC alone for CPM using meta-analytical methodology, focusing on survival outcomes. Secondary outcomes assessed included morbidity, mortality, quality of life (QOL), and health economics (HE). METHODS: An electronic literature search was conducted to identify studies comparing survival following CRS+HIPEC vs SC for CPM. The odds ratio (OR) was calculated using the Mantel-Haenszel method with corresponding 95% confidence intervals (CI) and P-values. Heterogeneity was examined using the Q-statistic and quantified with I(2). The fixed-effect model (FEM) was used in the absence of significant heterogeneity. For included studies, 2- and 5-year survival was compared for CRS+HIPEC vs SC alone. RESULTS: Four studies (three case-control, one RCT) provided comparative survival data for patients undergoing CRS+HIPEC (n=187) vs SC (n=155) for CPM. Pooled analysis demonstrated superior 2-year (OR 2.78; 95% CI 1.72-4.51; P=0.001) and 5-year (OR 4.07; 95% CI 2.17-7.64; P=0.001) survival with CRS+HIPEC compared with SC. Mortality ranged from 0 to 8%. No data were available for the assessment of QOL or HE. CONCLUSIONS: Although limited by between-study heterogeneity, the data support the assertion that in carefully selected patients, multimodal treatment of CPM with CRS+HIPEC has a highly positive prognostic impact on medium- and long-term survival compared with SC alone. There is a paucity of comparative data available on morbidity, QOL, and HE.

FOXO3 expression during colorectal cancer progression: biomarker potential reflects a tumour suppressor role.

BACKGROUND: In previous studies, the Forkhead/winged-helix-box-class-O3 (FOXO3) transcription factor has displayed both tumour suppressive and metastasis-promoting properties.To clarify its role in human colorectal cancer (CRC) progression, we examined in vivo FOXO3 expression at key points of the metastatic cascade. METHODS: Formalin-fixed paraffin-embedded resection specimens from normal colon, adenomas, primary CRC specimens of different pathological stage and CRC specimens with matched liver metastases were used to generate three separate custom-designed tissue microarray (TMA) representations of metastatic progression. Triplicate cores, immunostained for FOXO3 were scored semiquantitatively by two investigators. RESULTS: The FOXO3 expression is significantly reduced in CRC specimens compared with normal tissue, and progressive FOXO3 downregulation is associated with advancing pathological stage. In addition, recurrent stage I/II primary tumours show a significantly lower FOXO3 expression compared with stage-matched non-recurrent tumours. When stratified according to high and low FOXO3 expression, mean disease-free survival in the low-expressing group was 28 months (95% CI 15.8-50.6) compared with 64 months (95% CI 52.9-75.4) in the high-expressing group. CONCLUSION: We have demonstrated an association between low FOXO3 expression and CRC progression in vivo using purpose-designed TMAs. Forkhead/winged-helix-box-class-O3 may represent a novel biomarker of nodal and distant disease spread with clinical utility in CRC.

Pleiotropic actions of miR-21 highlight the critical role of deregulated stromal microRNAs during colorectal cancer progression.

The oncogene microRNA-21 (miRNA; miR-21) is overexpressed in most solid organ tumours; however, a recent examination of stage II colorectal cancer (CRC) specimens suggests this may be a stromal phenomenon and not only a feature of cancer cells. In vitro and in vivo studies show that miR-21 has potent pro-metastatic effects in various malignant carcinoma cell lines. The tumour microenvironment has also been identified as a key actor during the metastatic cascade; however to date the significance of deregulated miR-21 expression within the cancer-associated stroma has not been examined. In the present study, a quantitative RT-PCR-based analysis of laser microdissected tissue confirmed that miR-21 expression is associated with a four-fold mean increase in CRC stroma compared with normal tissue. In situ hybridisation using locked nucleic acid probes localised miR-21 expression predominantly to fibroblasts within tumour-associated stroma. To study the molecular and biological impact of deregulated stromal miR-21 in CRC, stable ectopic expression was induced in immortalised fibroblasts. This resulted in upregulated α-smooth muscle actin expression implying miR-21 overexpression is driving the fibroblast-to-myofibroblast transdifferentiation. Conditioned medium from miR-21-overexpressing fibroblasts protected CRC cells from oxaliplatin-induced apoptosis and increased their proliferative capacity. 3D organotypic co-cultures containing fibroblasts and CRC cells revealed that ectopic stromal miR-21 expression was associated with increased epithelial invasiveness. Reversion-inducing cysteine-rich protein with kazal motifs, an inhibitor of matrix-remodelling enzyme MMP2, was significantly downregulated by ectopic miR-21 in established and primary colorectal fibroblasts with a reciprocal rise in MMP2 activity. Inhibition of MMP2 abrogated the invasion-promoting effects of ectopic miR-21. This data, which characterises a novel pro-metastatic mechanism mediated by miR-21 in the CRC stroma, highlights the importance of miRNA deregulation within the tumour microenvironment and identifies a potential application for stromal miRNAs as biomarkers in cancer.

A prospective case-control study of extralevator abdominoperineal excision (ELAPE) of the rectum versus conventional laparoscopic and open abdominoperineal excision: comparative analysis of short-term outcomes and quality of life.

BACKGROUND: Conventional abdominoperineal excision (APE) of the rectum is associated with higher circumferential resection margin (CRM) involvement, increased local recurrence, and reduced survival compared to anterior resection. A more radical extralevator APE (ELAPE) technique may improve oncological outcome. However, this technique may confer additional morbidity, and little comparative data on short-term outcomes have been reported. This study compares short-term outcomes and quality of life (QOL) after open and laparoscopic ELAPE, laparoscopic APE (LAPE), and open APE (OAPE). METHODS: Data on all ELAPE and 10 consecutive LAPE and OAPE were extracted from a prospective database. Perioperative care and follow-up were standardized. QOL was assessed using EORTC questionnaires. RESULTS: Sixteen ELAPE (14 laparoscopic), 10 LAPE, and 10 OAPE were included. Demographics, tumour stage, and neoadjuvant therapy use were comparable. Operative time was higher with ELAPE than LAPE and OAPE (295, 207.5, and 157.5 min, respectively, p = 0.01). A porcine collagen perineal mesh was used in 9 patients undergoing ELAPE but in no LAPE or OAPE patients. No difference in 30-day complications, re-admission, or length of stay was noted. ELAPE and LAPE were associated with earlier removal of urinary catheter (p = 0.02), yet other enhanced recovery after surgery (ERAS) parameters were equivalent. All ELAPE resections were R0 with no positive CRM identified. One LAPE and 2 OAPE were R1 resections. Analysis revealed no deterioration in QOL with ELAPE, with equivalent global health status. CONCLUSIONS: The results of this study suggest that ELAPE is not associated with deterioration in short-term outcomes or QOL when compared with LAPE or OAPE.

The adaptive immune response to colorectal cancer: from the laboratory to clinical practice.

INTRODUCTION: Analysis of the adaptive immune system in the microenvironment of colorectal cancer is suggested to offer new insights into tumour biology and prognostic information independent of TNM staging. We aimed to review recent findings to investigate the potential for clinical use. METHODS: Relevant papers were identified through online searches regarding tumour infiltrating lymphocytes (TIL) in colorectal cancer. Identified papers were studied, focusing on clinically applicable uses for TIL data in the management of colorectal cancer. FINDINGS: The majority of identified studies were retrospective and observational in nature. The widest TIL investigation was in post resection prognosis but TIL subtypes, counts and methodology showed variability between studies. Recent reports explored TIL in predicting response to adjuvant and neoadjuvant treatments. CONCLUSION: An increasing body of evidence supports that visibility of colorectal cancer to immune attack is substantial and that it limits disease progression. Analysis of the adaptive immune infiltrate in resected colorectal cancer specimens offers prognostic information which is independent of conventionally measured parameters and potentially superior in predictive value.

Acute radiation enteritis causing small bowel obstruction.

Although much is known about the late intestinal side effects of radiation, comparatively little has been published about its acute complications. We present a case of a small bowel obstruction due to acute radiation enteritis. As radiotherapy continues to expand its role in the management of oncological disease, clinicians should remain alert to the resulting undesired effects.

Early experience with laparoscopic extralevator abdominoperineal excision within an enhanced recovery setting: analysis of short-term outcomes and quality of life.

INTRODUCTION: Conventional abdominoperineal excision for low rectal cancer has a higher local recurrence and reduced survival compared to anterior resection. An extralevator abdominoperineal excision (ELAPE) may improve outcome through removal of increased tissue in the distal rectum. Experience with ELAPE is limited and no studies have reported on quality of life (QOL) following this procedure. We describe a minimally invasive approach to ELAPE within an enhanced recovery programme, and present short-term results and QOL analyses. METHODS: All laparoscopic ELAPEs were included in a prospective database. Demographics, intra-operative and post-operative outcomes were evaluated. Postoperative QOL was assessed using the European Organisation for Research and Treatment of Cancer (EORTC) questionnaires QLQ-C30 and QLQ-CR29. RESULTS: Thirteen laparoscopic ELAPEs were performed over a two-year period. All were enrolled in an enhanced recovery programme. The median age was 76. The median tumour height was 20 mm (range: 0-50 mm) from the dentate line and all patients received neoadjuvant treatment. The median duration of surgery was 300 minutes (range: 120-488 minutes), the mean blood loss was 150 ml and one procedure was converted to open surgery. There was no circumferential resection margin involvement or tumour perforation. The median duration of use of intravenous fluid, patient controlled analgesia and urinary catheterisation was 2, 2 and 2.5 days respectively and the median length of hospital stay was 7.5 days. Two patients developed perineal wound dehiscence. QOL analysis revealed high global health status (90.8), physical (91.3), emotional (98.3) and social functioning (100) scores, which compared favourably with EORTC reference values and published QOL scores following conventional abdominoperineal excision. CONCLUSIONS: Laparoscopic ELAPE within an enhanced recovery setting is a feasible and safe approach with acceptable short-term outcomes and post-operative quality of life.

Surgery for recurrent rectal cancer: technical notes and management of complications.

Local recurrence following surgery for rectal cancer remains a significant clinical problem and poses major therapeutic challenges. Radical surgical salvage is the only option with potential for curative treatment and is indicated in carefully selected patients. Surgery also provides acceptable palliation in certain cases. Nevertheless, such surgery is challenging, not commonly used, and historically associated with considerable morbidity and mortality. In more recent times, improvements in surgical techniques, reconstruction methods and management of perioperative complications have helped expand the options available for patients with recurrent rectal cancer. This review article highlights the techniques employed at our institution for the management of locally recurrent rectal cancer with particular emphasis on the surgical approaches, the methods used for reconstruction and the avoidance of complications.

Robotic colorectal surgery: hype or new hope? A systematic review of robotics in colorectal surgery.

AIM: Robotic colorectal surgery is an emerging field and may offer a solution to some of the difficulties inherent to conventional laparoscopic surgery. The aim of this review is to provide a comprehensive and critical analysis of the available literature on the use of robotic technology in colorectal surgery. METHOD: Studies reporting outcomes of robotic colorectal surgery were identified by systematic searches of electronic databases. Outcomes examined included operating time, length of stay, blood loss, complications, cost, oncological outcome, and conversion rates. RESULTS: Seventeen Studies (nine case series, seven comparative studies, one randomized controlled trial) describing 288 procedures were identified and reviewed. Study heterogeneity precluded a meta-analysis of the data. Robotic procedures tend to take longer and cost more, but may reduce the length of stay, blood loss, and conversion rates. Complication profiles and short-term oncological outcomes are similar to laparoscopic surgery. CONCLUSION: Robotic colorectal surgery is a promising field and may provide a powerful additional tool for optimal management of more challenging pathology, including rectal cancer. Further studies are required to better define its role.

MicroRNAs: key players in carcinogenesis and novel therapeutic targets.

MicroRNAs (miRNAs) represent a recently uncovered class of small and endogenous non-coding RNAs. MiRNA function is critical to normal cellular processes such as differentiation and apoptosis, and recent studies have demonstrated that deregulated miRNA expression contributes to the malignant phenotype. The purpose of this review is to summarise these findings in relation to the most common human malignancies, and to analyse the clinical and therapeutic opportunities they provide.