Effect of differing flap reconstruction strategies in perineal closure following advanced pelvic oncological resection: a retrospective cohort study.

INTRODUCTION: Advancing approaches to locally invasive pelvic malignancy creates a large tissue defect resulting in perineal wound complications, dehiscence, and perineal hernia. Use of reconstructive flaps such as vertical rectus abdominus myocutaneous (VRAM) flap, gracilis, anterolateral thigh and gluteal flaps have been utilised in our institution to address perineal closure. The authors compared outcomes using different flap techniques along with primary perineal closure in advanced pelvic oncological resection. METHODS: A prospectively maintained database of patients undergoing advanced pelvic oncological resection in a single tertiary hospital was retrospectively analysed. This study included consecutive patients between 2014 and 2021 according to the Strengthening The Reporting of Cohort Studies in Surgery (STROCSS) criteria. Primary outcome measures were the frequency of postoperative perineal complications between primary closure, VRAM, gluteal and thigh (anterolateral thigh and gracilis) reconstruction. RESULTS: One hundred twenty-two patients underwent advanced pelvic resection with perineal closure. Of these, 40 patients underwent extra-levator abdominoperineal resection, and 70 patients underwent pelvic exenteration. Sixty-four patients received reconstructive flap closure, which included VRAM (22), gluteal (21) and thigh flaps (19). Perineal infection and dehiscence rates were low. Infection rates were lower in the flap group despite a higher rate of radiotherapy ( P <0.050). Reoperation rates were infrequent (<10%) but specific for each flap, such as donor-site hernia following VRAM and flap dehiscence after thigh flap reconstruction. CONCLUSIONS: In patients who are at high risk of postoperative perineal infections, reconstructive flap closure offers acceptable outcomes. VRAM, gluteal and thigh flaps offer comparable outcomes and can be tailored to the individual patient.

Volume-outcome relationship in intra-abdominal robotic-assisted surgery: a systematic review.

As robotic-assisted surgery (RAS) expands to smaller centres, platforms are shared between specialities. Healthcare providers must consider case volume and mix required to maintain quality and cost-effectiveness. This can be informed, in-part, by the volume-outcome relationship. We perform a systematic review to describe the volume-outcome relationship in intra-abdominal robotic-assisted surgery to report on suggested minimum volumes standards. A literature search of Medline, NICE Evidence Search, Health Technology Assessment Database and Cochrane Library using the terms: "robot*", "surgery", "volume" and "outcome" was performed. The included procedures were gynecological: hysterectomy, urological: partial and radical nephrectomy, cystectomy, prostatectomy, and general surgical: colectomy, esophagectomy. Hospital and surgeon volume measures and all reported outcomes were analysed. 41 studies, including 983,149 procedures, met the inclusion criteria. Study quality was assessed using the Newcastle-Ottawa Quality Assessment Scale and the retrieved data was synthesised in a narrative review. Significant volume-outcome relationships were described in relation to key outcome measures, including operative time, complications, positive margins, lymph node yield and cost. Annual surgeon and hospital volume thresholds were described. We concluded that in centres with an annual volume of fewer than 10 cases of a given procedure, having multiple surgeons performing these procedures led to worse outcomes and, therefore, opportunities should be sought to perform other complimentary robotic procedures or undertake joint cases.

Targeting Metastatic Colorectal Cancer with Immune Oncological Therapies.

Metastatic colorectal cancer carries poor prognosis, and current therapeutic regimes convey limited improvements in survival and high rates of detrimental side effects in patients that may not stand to benefit. Immunotherapy has revolutionised cancer treatment by restoring antitumoural mechanisms. However, the efficacy in metastatic colorectal cancer, is limited. A literature search was performed using Pubmed (Medline), Web of Knowledge, and Embase. Search terms included combinations of immunotherapy and metastatic colorectal cancer, primarily focusing on clinical trials in humans. Analysis of these studies included status of MMR/MSS, presence of combination strategies, and disease control rate and median overall survival. Evidence shows that immune checkpoint inhibitors, such as anti-PD1 and anti-PD-L1, show efficacy in less than 10% of patients with microsatellite stable, MMR proficient colorectal cancer. In the small subset of patients with microsatellite unstable, MMR deficient cancers, response rates were 40-50%. Combination strategies with immunotherapy are under investigation but have not yet restored antitumoural mechanisms to permit durable disease regression. Immunotherapy provides the potential to offer additional strategies to established chemotherapeutic regimes in metastatic colorectal cancer. Further research needs to establish which adjuncts to immune checkpoint inhibition can unpick resistance, and better predict which patients are likely to respond to individualised therapies to not just improve response rates but to temper unwarranted side effects.

Interferon-gamma increases monocyte PD-L1 but does not diminish T-cell activation.

Immune dysfunction can occur during sepsis or following major trauma. Decreased monocyte HLA-DR expression and cytokine responses are associated with mortality. Recent studies have shown that adaptive immune system defects can also occur in such patients, characterised by increased PD-L1 expression and associated T-cell anergy. The aim of this study was to determine the effects of an immune adjuvant, interferon-gamma, on monocyte PD-L1 expression and T-cell activation in an ex-vivo human whole blood model of infection. We found that with interferon-gamma treatment, monocytes had increased HLA-DR expression and augmented TNF-α production in response to LPS stimulation, with a decrease in IL-10 levels. Both LPS and interferon-gamma increased the level of monocyte PD-L1 expression, and that a combination of both agents synergistically stimulated a further increase in PD-L1 levels as measured by flow cytometry. However, despite elevated PD-L1 expression, both CD4 and CD8 T-cell activation was not diminished by the addition of interferon-gamma treatment. These findings suggest that PD-L1 may not be a reliable marker for T-cell anergy, and that interferon-gamma remains an adjuvant of interest that can improve the monocyte inflammatory response while preserving T-cell activation.

The role and function of IκKα/ß in monocyte impairment.

Following major trauma, sepsis or surgery, some patients exhibit an impaired monocyte inflammatory response that is characterized by a decreased response to a subsequent bacterial challenge. To investigate this poorly understood phenomenon, we adopted an in-vitro model of endotoxin tolerance utilising primary human CD14 + monocytes to focus on the effect of impairment on IκKα/ß, a critical part of the NFκB pathway. Impaired monocytes had decreased IκKα mRNA and protein expression and decreased phosphorylation of the IκKα/ß complex. The impaired monocyte secretome demonstrated a distinct cytokine/chemokine footprint from the naïve monocyte, and that TNF-α was the most sensitive cytokine or chemokine in this setting of impairment. Inhibition of IκKα/ß with a novel selective inhibitor reproduced the impaired monocyte phenotype with decreased production of TNF-α, IL-6, IL-12p70, IL-10, GM-CSF, VEGF, MIP-1ß, TNF-ß, IFN-α2 and IL-7 in response to an LPS challenge. Surgical patients with infection also exhibited an impaired monocyte phenotype and had decreased SITPEC, TAK1 and MEKK gene expression, which are important for IκKα/ß activation. Our results emphasize that impaired monocyte function is, at least in part, related to dysregulated IκKα/ß activation, and that IκKα/ß is likely involved in mounting a sufficient monocyte inflammatory response. Future studies may wish to focus on adjuvant therapies that augment IκKα/ß function to restore monocyte function in this clinically important problem.

The microRNA-200 family acts as an oncogene in colorectal cancer by inhibiting the tumor suppressor RASSF2.

This study aimed to determine whether manipulation of the microRNA-200 (miR-200) family could influence colon adenocarcinoma cell behavior. The miR-200 family has a significant role in tumor suppression and functions as an oncogene. In vitro studies on gain and loss of function with small interfering RNA demonstrated that the miR-200 family could regulate RASSF2 expression. Knockdown of the miR-200 family in the HT-29 colon cancer cell line increased KRAS expression but decreased signaling in the MAPK/ERK signaling pathway through reduced ERK phosphorylation. Increased expression of the miR-200 family in the CCD-841 colon epithelium cell line increased KRAS expression and led to increased signaling in the MAPK/ERK signaling pathway but increased ERK phosphorylation. Functionally, knockdown of the miR-200 family led to decreased cell proliferation in the HT-29 cells; therefore, increased miR-200 family expression could increase cell proliferation in the CCD-841 cell line. The present study included a large paired miR array dataset (n=632), in which the miR-200 family was significantly found to be increased in colon cancer when compared with normal adjacent colon epithelium. In a miR-seq dataset (n=199), the study found that miR-200 family expression was increased in localized colon cancer compared with metastatic disease. Decreased expression was associated with poorer overall survival. The miR-200 family directly targeted RASSF2 and was inversely correlated with RASSF2 expression (n=199, all P<0.001). Despite the well-defined role of the miR-200 family in tumor suppression, the present findings demonstrated a novel function of the miR-200 family in tumor proliferation.

Temporal expression of circulating miRNA after severe injury.

BACKGROUND: Severe injury can lead to immune dysfunction and predispose patients to infection and death. Micro-RNAs regulate gene expression and may act as biomarkers for susceptibility to infection. The aim of this study was to examine the temporal and differential expression of previously identified dysregulated micro-RNAs in patients with severe injury. METHODS: Fourteen severely injured patients requiring transfusion were enrolled prospectively in this study approved by our institutional review board. Inclusion criteria consisted of adult patients deemed clinically to be in hemorrhagic shock necessitating transfusion in the acute phase of their injury care. Peripheral blood samples were obtained after admission to the surgical intensive care unit and again at 6, 12, 24, and 48 hours after admission. The samples obtained at arrival to the intensive care unit and 24 and 48 hours later were analyzed in this data set. Fourteen healthy volunteers served as controls. The 10 dysregulated micro-RNAs identified in a prior study at the 12-hour time point and important genes in innate immunity were measured using quantitative reverse transcription-polymerase chain reaction. RESULTS: The participants were 21-77 years old (median, 42), 78% were male, and their Injury Severity Score ranged from 11 to 43 (median, 27); 11 had blunt and 3 had penetrating injuries. Three were intubated and 5 had received blood products before arrival at the hospital. Base deficit on hospital admission was 3-20 (median, 9). All patients required blood transfusion secondary to blood loss sustained during injury. Eleven of the 14 patients went directly to the operating room from the emergency department for control of the source of hemorrhage. Survival to discharge was 93%. Seven patients developed infection. Compared with healthy controls, miR-106a was downregulated at all time points compared with controls (P < .05). miR-618 was upregulated in initial blood draws (P < .05) and at 24 and 48 hours (P < .06). Tumor necrosis factor α and human leukocyte antigen-DR (HLA-DR) were downregulated, and interleukin-10 and PD-L1 were upregulated (P < .05). In patients who developed infection, miR-106a levels appeared more downregulated than those who did not develop infection. CONCLUSION: miR-106a was downregulated in trauma patients after major injury for up to 48 hours after intensive care unit admission. Tumor necrosis factor α and interleukin-10 are targeted by miR-106a, which are regulators of the immune response. Manipulation of micro-RNA expression may be a therapeutic target for immune dysfunction.

Long-term outcomes following ileal pouch-anal anastomosis in patients with indeterminate colitis.

BACKGROUND: The advisability of performing ileal pouch-anal anastomosis for patients with indeterminate colitis is debated. Indeterminate colitis is found in up to 15% of inflammatory bowel disease colectomy specimens. We determined long-term outcomes in patients diagnosed with indeterminate colitis undergoing ileal pouch-anal anastomosis. METHODS: Fifty-six patients were included with a mean follow-up of 14 ± 7 years. Long-term behavior was defined based on surgeon assessment as "Crohn disease-like" in patients who subsequently developed clear signs of Crohn disease and as "non-Crohn disease-like." Long-term function was assessed using the Cleveland Global Quality of Life and Pouch Functional Score. RESULTS: Thirty-nine percent of patients developed Crohn disease-like behavior, and 61% developed non-Crohn disease-like behavior. Both groups experienced a high rate of pouchitis (57%). Crohn disease-like patients required more anti-inflammatory/immunomodulatory medications (95% vs 18%, P < .001), dilatations for afferent-limb strictures (41% vs 0%, P < .001), and pouch reoperations (32% vs 6%, P = .02). Eight patients required pouch excision or diversion (7 with Crohn disease-like behavior). The Pouch Functional Score was equivalent between groups. CONCLUSION: Long-term function after ileal pouch-anal anastomosis for the majority of indeterminate colitis patients was good. Approximately 40% eventually exhibited Crohn disease-like behavior, but the majority had acceptable function and quality of life. Ileal pouch-anal anastomosis is an appropriate surgical option for indeterminate colitis patients after informed consent.

The effect of IκK-16 on lipopolysaccharide-induced impaired monocytes.

This study focuses on impaired monocyte function, which occurs in some patients after trauma, major elective surgery, or sepsis. This monocyte impairment increases the risk of secondary infection and death. We aimed to determine the influence IκK-16 had on monocytes using an ex-vivo model of human monocyte impairment. We included the effects of the well-studied comparators interferon-gamma (IFN-γ) and granulocyte-macrophage colony-stimulating factor (GM-CSF) on impaired monocytes. Primary human monocytes were stimulated with 10ng/mL of lipopolysaccharide (LPS) for 16h and then challenged with 100ng/mL LPS to assess the monocyte inflammatory response. Treatment regimens, consisting of either IκK-16, IFN-γ, or GM-CSF, were administered to impaired monocytes near the time of initial LPS stimulation. Stimulation with 10ng/mL LPS initially promoted a pro-inflammatory response but subsequently impaired production of both tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) and decreased HLA-DR expression. IκK-16 treatment attenuated TNF-α production and programmed death-ligand 1 (PD-L1) expression and increased IL-10 and CD14 expression. IFN-γ treatment increased TNF-α production as well as PD-L1 and HLA-DR expression. In conclusion, limiting early inflammation with IκK-16 suppresses TNF-α production and PD-L1 expression but enhances IL-10 production and preserves CD14 expression for potential future exposure to infective stimuli.

Women in surgery: A longer term follow-up.

BACKGROUND: There are an increasing number of women in surgery. Previously, many questions focused upon their ability to complete surgical training and contribute fully to the surgical workforce. More meaningful information lies in identifying the long-term follow-up of where, and in what specialty, women residents eventually practice. METHODS: All residents entering general surgery training at the University of Louisville between 1996 and 2009 were studied. Comparison between men and women was performed for program completion, length of residency training, and eventual specialty practice. RESULTS: One hundred and eight residents entered general surgery residency. Twenty-three (21%) did not complete training. There was no difference in attrition rates between men or women (22% vs. 19%, p = 0.77). Women completing residency were just as likely to practice general surgery (either private or academic practice) as their male counterparts (67% vs. 67% p = 0.96). CONCLUSIONS: Women are a valuable resource in surgery and are able to complete a vigorous residency. Long-term follow-up is crucial and permits us to evaluate this important group of trainees practicing surgery today.

Plasma microRNA Profile Differentiates Crohn's Colitis From Ulcerative Colitis.

Background: Inflammatory bowel disease (IBD) is commonly divided into 2 entities: Crohn's disease (CD) and ulcerative colitis (UC). Differentiating between these entities when dealing with IBD confined to the colon is important, especially when planning surgical treatment. Due to ambiguous histological or endoscopic findings, accurate diagnosis is not possible in up to 15% of cases. The aim of this study was to determine whether plasma microRNAs (miRNAs) can help differentiate Crohn's colitis (CC) from ulcerative colitis. Methods: Patients with isolated CC and with UC were enrolled in our study from January 2010 to May 2016. Peripheral blood was collected, and total RNA was isolated from plasma. Screening was performed for 380 common miRNAs. miRNAs that were differentially expressed between these 2 groups were chosen, and their differential expression was confirmed using single miRNA assays in a larger sample size. A predictive model was generated using these data. Significantly differentially expressed miRNAs were then validated utilizing the predictive model to assess blinded data from the single assays. Results: Screening was performed on 8 patients from each group. Seven differentially expressed miRNAs were chosen for single assay confirmation. Two miRNAs (miR-598, miR-642) were consistently different between the patient groups (P = 0.013, P = 0.005). Using blinded data, these 2 miRNAs were validated using the predictive model, achieving an overall accuracy of 75% (95% confidence interval, 40.7-92.9). Conclusions: We identified 2 plasma miRNAs that differentiated CC from UC. Our data indicate the promise and feasibility of a plasma miRNA-based assay to distinguish between these 2 conditions.

Rapid tissue regeneration induced by intracellular ATP delivery-A preliminary mechanistic study.

We have reported a new phenomenon in acute wound healing following the use of intracellular ATP delivery-extremely rapid tissue regeneration, which starts less than 24 h after surgery, and is accompanied by massive macrophage trafficking, in situ proliferation, and direct collagen production. This unusual process bypasses the formation of the traditional provisional extracellular matrix and significantly shortens the wound healing process. Although macrophages/monocytes are known to play a critical role in the initiation and progression of wound healing, their in situ proliferation and direct collagen production in wound healing have never been reported previously. We have explored these two very specific pathways during wound healing, while excluding confounding factors in the in vivo environment by analyzing wound samples and performing in vitro studies. The use of immunohistochemical studies enabled the detection of in situ macrophage proliferation in ATP-vesicle treated wounds. Primary human macrophages and Raw 264.7 cells were used for an in vitro study involving treatment with ATP vesicles, free Mg-ATP alone, lipid vesicles alone, Regranex, or culture medium. Collagen type 1α 1, MCP-1, IL-6, and IL-10 levels were determined by ELISA of the culture supernatant. The intracellular collagen type 1α1 localization was determined with immunocytochemistry. ATP-vesicle treated wounds showed high immunoreactivity towards BrdU and PCNA antigens, indicating in situ proliferation. Most of the cultured macrophages treated with ATP-vesicles maintained their classic phenotype and expressed high levels of collagen type 1α1 for a longer duration than was observed with cells treated with Regranex. These studies provide the first clear evidence of in situ macrophage proliferation and direct collagen production during wound healing. These findings provide part of the explanation for the extremely rapid tissue regeneration, and this treatment may hold promise for acute and chronic wound care.

Blood-based microRNAs as biomarkers for the diagnosis of colorectal cancer: a systematic review and meta-analysis.

BACKGROUND: Colorectal cancer (CRC) is common and associated with significant mortality. Current screening methods for CRC lack patient compliance. microRNAs (miRNAs), identified in body fluids, are negative regulators of gene expression and are dysregulated in many cancers, including CRC. This paper summarises studies identifying blood-based miRNAs dysregulated in CRC compared with healthy controls in an attempt to evaluate their use as a screening tool for the diagnosis of CRC. METHODS: A search of electronic databases (PubMed and EMBASE) and grey literature was performed between January 2002 and April 2016. Studies reporting plasma or serum miRNAs in the diagnosis of CRC compared with healthy controls were selected. Patient demographics, type of patient sample (serum or plasma), method of miRNA detection, type of normalisation, and the number of significantly dysregulated miRNAs identified were recorded. Statistical evaluation of dysregulated miRNAs using sensitivity, specificity, and area under the curve (AUC) was performed. RESULTS: Thirty-four studies investigating plasma or serum miRNAs in the diagnosis of CRC were included. A total of 31 miRNAs were found to be either upregulated (n=17) or downregulated (n=14) in CRC cases as compared with controls. Fourteen studies identified panels of ⩾2 dysregulated miRNAs. The highest AUC, 0.943, was identified using a panel of 4 miRNAs with 83.3% sensitivity and 93.1% specificity. Meta-analysis of studies identifying a single dysregulated miRNA in CRC cases compared with controls was performed. Overall sensitivity and specificity of 28 individual miRNAs in the diagnosis of CRC were 76% (95% CI 72%-80%) and 76% (95% CI 72%-80%), respectively, indicating good discriminative ability of miRNAs as biomarkers for CRC. These data did not change with sensitivity analyses. CONCLUSIONS: Blood-based miRNAs distinguish patients with CRC from healthy controls with high sensitivity and specificity comparable to other common and invasive currently used screening methods for CRC. In future, miRNAs may be used as a relatively non-invasive blood-based marker for detection of CRC.

A Highly Predictive Model for Diagnosis of Colorectal Neoplasms Using Plasma MicroRNA: Improving Specificity and Sensitivity.

OBJECTIVE: To develop a plasma-based microRNA (miRNA) diagnostic assay specific for colorectal neoplasms, building upon our prior work. BACKGROUND: Colorectal neoplasms [colorectal cancer (CRC) and colorectal advanced adenoma (CAA)] frequently develop in individuals at ages when other common cancers also occur. Current screening methods lack sensitivity, specificity, and have poor patient compliance. METHODS: Plasma was screened for 380 miRNAs using microfluidic array technology from a "Training" cohort of 60 patients, (10 each) control, CRC, CAA, breast cancer, pancreatic cancer, and lung cancer. We identified uniquely dysregulated miRNAs specific for colorectal neoplasia (P < 0.05, false discovery rate: 5%, adjusted α = 0.0038). These miRNAs were evaluated using single assays in a "Test" cohort of 120 patients. A mathematical model was developed to predict blinded sample identity in a 150 patient "Validation" cohort using repeat-sub-sampling validation of the testing dataset with 1000 iterations each to assess model detection accuracy. RESULTS: Seven miRNAs (miR-21, miR-29c, miR-122, miR-192, miR-346, miR-372, and miR-374a) were selected based upon P value, area under the curve (AUC), fold change, and biological plausibility. Area under the curve (±95% confidence interval) for "Test" cohort comparisons were 0.91 (0.85-0.96) between all neoplasia and controls, 0.79 (0.70-0.88) between colorectal neoplasia and other cancers, and 0.98 (0.96-1.0) between CRC and colorectal adenomas. In our "Validation" cohort, our mathematical model predicted blinded sample identity with 69% to 77% accuracy, 67% to 76% accuracy, and 86% to 90% accuracy for each comparison, respectively. CONCLUSIONS: Our plasma miRNA assay and prediction model differentiate colorectal neoplasia from patients with other neoplasms and from controls with higher sensitivity and specificity compared with current clinical standards.