Role of ablation therapy in conjunction with surgical resection for neuroendocrine tumors involving the liver.

BACKGROUND: Resection of hepatic metastasis from neuroendocrine tumors (NETs) improves quality of life and prolongs 5-year survival. Ablation can be utilized with surgery to achieve complete resection. Although several studies report long-term outcomes for patients undergoing ablation, none have explored perioperative effects of ablation in patients with metastatic NETs. AIM: To determine if intra-operative ablation during hepatectomy increases risk of adverse outcomes such as surgical site infections (SSIs), bleeding, and bile leak. METHODS: A retrospective analysis of the hepatectomy National Surgical Quality Improvement Program database from 2015-2019 was performed to determine the odds of SSIs, bile leaks, or bleeding in patients undergoing intraoperative ablation when compared to hepatectomy alone. RESULTS: Of the 966 patients included in the study, 298 (30.9%) underwent ablation during hepatectomy. There were 78 (11.7%) patients with SSIs in the hepatectomy alone group and 39 (13.1%) patients with a SSIs in the hepatectomy with ablation group. Bile leak occurred in 41 (6.2%) and 14 (4.8%) patients in the two groups, respectively; bleeding occurred in 117 (17.5%) and 33 (11.1%), respectively. After controlling for confounding variables, ablation did not increase risk of SSI (P = 0.63), bile leak (P = 0.34) or bleeding (P = 0.07) when compared to patients undergoing resection alone on multivariate analysis. CONCLUSION: Intraoperative ablation with hepatic resection for NETs is safe in the perioperative period without significant increased risk of infection, bleeding, or bile leak. Surgeons should utilize this modality when appropriate to achieve optimal disease control and outcomes.

Post-operative morbidity after neoadjuvant chemotherapy and resection for gallbladder cancer: A national surgical quality improvement program analysis.

BACKGROUND: Gallbladder cancer is the most common malignancy of the biliary tract. Neoadjuvant chemotherapy (NACT) has improved overall survival by enabling R0 resection. Currently, there is no consensus of guidelines for neoadjuvant therapy in gallbladder cancer. As investigations continue to analyze the regimen and benefit of NACT for ongoing care of gallbladder cancer patients, we examined American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database to determine if there was higher morbidity among the neoadjuvant group within the 30-day post-operative period. We hypothesized patients who underwent NACT were more likely to have higher post-operative morbidity. AIM: To investigate the 30-day post-operative morbidity outcomes between patients who received NACT and underwent surgery and patients who only had surgery. METHODS: A retrospective analysis of the targeted hepatectomy NSQIP data between 2015 and 2019 was performed to determine if NACT in gallbladder cancer increased the risk for post-operative morbidity (bile leak, infection rate, rate of converting to open surgery, etc.) compared to the group who only had surgery. To calculate the odds ratio for the primary and secondary outcomes, a crude logistic regression was performed. RESULTS: Of the 452 patients, 52 patients received NACT prior to surgery. There were no statistically significant differences in the odds of morbidity between the two groups, including bile leak [odds ratio (OR), 0.69; 95% confidence interval (95%CI): 0.16-2.10; P = 0.55], superficial wound infection (OR, 0.58; 95%CI: 0.03-3.02; P = 0.61), and organ space wound infection (OR, 0.63; 95%CI: 0.18-1.63; P = 0.61). CONCLUSION: There was no significant difference in the risk of 30-day post-operative morbidity between the NACT and surgery group and the surgery only group.

Radiation therapy prior to a pancreaticoduodenectomy for adenocarcinoma is associated with longer operative times and higher blood loss.

BACKGROUND: Pancreatic adenocarcinoma is currently the fourth leading cause of cancer-related deaths in the United States. In patients with "borderline resectable" disease, current National Comprehensive Cancer Center guidelines recommend the use of neoadjuvant chemoradiation prior to a pancreaticoduodenectomy. Although neoadjuvant radiotherapy may improve negative margin resection rate, it is theorized that its administration increases operative times and complexity. AIM: To investigate the association between neoadjuvant radiotherapy and 30-d morbidity and mortality outcomes among patients receiving a pancreaticoduodenectomy for pancreatic adenocarcinoma. METHODS: Patients listed in the 2015-2019 National Surgery Quality Improvement Program data set, who received a pancreaticoduodenectomy for pancreatic adenocarcinoma, were divided into two groups based off neoadjuvant radiotherapy status. Multivariable regression was used to determine if there is a significant correlation between neoadjuvant radiotherapy, perioperative blood transfusion status, total operative time, and other perioperative outcomes. RESULTS: Of the 11458 patients included in the study, 1470 (12.8%) underwent neoadjuvant radiotherapy. Patients who received neoadjuvant radiotherapy were significantly more likely to require a perioperative blood transfusion [adjusted odds ratio (aOR) = 1.58, 95% confidence interval (CI): 1.37-1.82; P < 0.001] and have longer surgeries (insulin receptor-related receptor = 1.14, 95%CI: 1.11-1.16; P < 0.001), while simultaneously having lower rates of organ space infections (aOR = 0.80, 95%CI: 0.66-0.97; P = 0.02) and pancreatic fistula formation (aOR = 0.50, 95%CI: 0.40-0.63; P < 0.001) compared to those who underwent surgery alone. CONCLUSION: Neoadjuvant radiotherapy, while not associated with increased mortality, will impact the complexity of surgical resection in patients with pancreatic adenocarcinoma.

Gallbladder cancer: Historical treatment and new management options.

Gallbladder cancer is a rare, aggressive malignancy that has a poor overall prognosis. Effective treatment consists of early detection and surgical treatment. With the wide spread treatment of gallbladder disease with minimally invasive techniques, the rate of incidental gallbladder cancer has seen an equitable rise along with stage migration towards earlier disease. Although the treatment remains mostly surgical, newer modalities such as regional therapy as well as directed therapy based on molecular medicine has led to improved outcomes in patients with advanced disease. We aim to summarize the management of gallbladder cancer along with the newer developments in this formidable disease process.

Simultaneous Robot Assisted Colon and Liver Resection for Metastatic Colon Cancer.

INTRODUCTION: Simultaneous robot assisted colon and liver resections are being performed more frequently at present due to the expanded adoption of the robotic platform for surgical management of metastatic colon cancer. However, this approach has not been studied in detail with only case series available in the literature. The aim of this systematic review was to evaluate the current body of evidence on the feasibility of performing simultaneous robotic colon and liver resections. METHODS: A systematic review was performed through PubMed to identify relevant articles describing simultaneous colon and liver resections for metastatic colon cancer. RESULTS: A total of 28 patients underwent simultaneous resections robotically with an average operative time of 420.3 minutes and average blood loss of 275.6 ml. Postoperative stay was 8.6 days on average with all cases achieving negative surgical margins. CONCLUSIONS: Robotic simultaneous resection of colorectal cancer with liver metastases is technically feasible and seems oncologically equivalent to open or laparoscopic surgery. Further studies are urgently needed to assess benefits of robotic surgery in the patient population.

Clinicopathologic Features and Outcome of Adenocarcinoma of the Anal Canal: A Population-Based Study.

BACKGROUND: Anal canal adenocarcinoma (AA) is an uncommon tumor of the gastrointestinal tract. We seek to provide a detailed description of the incidence, demographics, and outcome of this rare tumor in the United States. METHODS: The data on anal canal adenocarcinoma from SEER Program, between 1973-2015, were extracted. We analyzed the incidence rates by demographics and tumor characteristics, followed by analysis of its impact on survival. RESULTS: The incidence of AA increased initially by 4.03% yearly from 1973 to 1985 but had a modest decline of 0.32% annually thereafter. The mean age for diagnosis of AA was 68.12 ± 14.02 years. Males outnumbered females by 54.8 to 45.2%. Tumors were mostly localized on presentation (44.4%) and moderately differentiated (41.1%). Age generally correlated with poor overall cancer survival. However, young patients (age <40 years) also showed poor long-term survival. Patients with localized disease and well-differentiated tumors showed better survival outcomes. Surgical intervention improved survival significantly as compared to patients who did not (116.7 months vs 42.7 months, p < 0.01). CONCLUSIONS: Anal canal adenocarcinoma demonstrated a poor bimodal cancer-free survival in both younger and older patient groups. Surgery significantly improves odds of survival and should be offered to patients amenable to intervention.

The Interplay of MicroRNA-34a, LGR4, EMT-Associated Factors, and MMP2 in Regulating Uveal Melanoma Cells.

Purpose: MicroRNA-34a (miR-34a) has been implicated in many biological processes. It is downregulated in uveal melanoma, and introduction of miR-34a inhibits the proliferation and migration of uveal melanoma cells. Leucine-rich repeat-containing G protein-coupled receptor 4 (LGR4) is a novel target of miR-34a identified first in retinal pigment epithelial cells. In this study, we sought to evaluate the interaction of miR-34a and LGR4 in uveal melanoma and its downstream mechanisms. Methods: The expression of LGR4, epithelial-mesenchymal transition (EMT)-associated factors, and matrix metalloproteinase 2 (MMP2) in uveal melanoma cells was assessed by immunoblotting and immunofluorescence analysis. MicroRNA-34a mimic molecules, LGR4 small interfering RNA (siRNA), or MMP2-specific siRNA were transiently transfected into uveal melanoma cells. In vitro scratch and Transwell assays were used to evaluate the migratory and invasive potential of the resultant uveal melanoma cells. Results: LGR4 is upregulated in uveal melanoma cells. Introduction of miR-34a significantly decreased the expression level of LGR4. Transfection with miR-34a or knockdown of LGR4 attenuated the aggressiveness of uveal melanoma cells. In addition, there was a decrease in the expression of mesenchymal markers N-cadherin, vimentin, and Snail following miR-34a introduction or knockdown of LGR4. Finally, MMP2 was found to be a downstream effector for miR-34a and LGR4 that regulates the migration and invasion of uveal melanoma cells. Conclusions: MicroRNA-34a negatively controls LGR4, thereby inhibiting the migration and invasion of uveal melanoma cells. Ultimately, both miR-34a and LGR4 impact the aggressiveness of uveal melanoma with alterations in the markers of the EMT. MMP2 is a downstream effector that influences the metastasis seen with uveal melanoma cells.

Double-barreled Wet Colostomy Versus Separate Urinary and Fecal Diversion in Patients Undergoing Total Pelvic Exenteration: A Cohort Meta-analysis.

BACKGROUND: The aim of this meta-analysis was to determine whether double-barreled wet colostomy (DBWC) provides similar urinary tract infection rates as separate urinary and fecal diversion (SUFD) in patients undergoing pelvic exenteration. METHODS: The MEDLINE, PubMed, Cochrane Library, and Scopus databases were systematically searched by two independent researchers. The primary endpoint was the urinary tract infection rate. The Mantel-Haenszel method with odds ratios with 95% confidence intervals (OR (95%CI)) was used as an effect measure for dichotomous variables. A random-effects model was used for the meta-analysis. Statistical heterogeneity among effect estimates was evaluated using I2 and Tau2. RESULTS: Three observational studies that included a total of 257 patients (159 DBWC; 98 SUFD) were included after 14 potentially eligible records were screened. Pooled urinary tract infection rates were 1.9% (3/159) in DBWC and 6.1% (6/98) in SUFD. This difference was not statistically significant [OR (95%CI) = 0.27 (0.06, 1.19); p=0.08] with low among-study heterogeneity (I2=0%). CONCLUSIONS: This meta-analysis did not find a significant difference in urinary tract infection rates between DBWC and SUFD in patients undergoing total pelvic exenteration. Further clinical studies will be required to further understand the pros and cons of these procedures.

Effects of combined menaquinone-4 and PTH1-34 treatment on osetogenesis and angiogenesis in calvarial defect in osteopenic rats.

PURPOSE: The aim of this study was to evaluate the effect of combining human parathyroid hormone (1-34) (PTH1-34; PTH) and menaquinone-4 (MK-4) on calvarial bone defect repair in osteopenic rats. METHODS: Fourteen week olds were subject to craniotomy for the establishment of osteopenic animal models fed through a chronically low-protein diet. After that, critical calvarial defect model was established and all rats were randomly divided into four groups: sham, MK-4, PTH, and PTH + MK-4. The animals received MK-4 (30 mg/kg/day), PTH1-34 (60 µg/kg, three times a week), or PTH1-34 (60 µg/kg, three times a week) plus MK-4 (30 mg/kg/day) for 8 weeks, respectively. Serum γ-carboxylated osteocalcin (Gla-OC) levels, histological and immunofluorescent labeling were employed to evaluate the bone formation and mineralization in calvarial bone defect. In addition, Microfil perfusion, immunohistochemical, and micro-CT suggested enhanced angiogenesis and bone formation in calvarial bone healing. RESULTS: In this study, treatment with either PTH1-34 or MK-4 promoted bone formation and vascular formation in calvarial bone defects compared with the sham group. In addition, combined treatment of PTH1-34 plus MK-4 increased serum level of Gla-OC, improved vascular number and vascular density, and enhanced bone formation in calvarial bone defect in osteopenic conditions as compared with monotherapy. CONCLUSIONS: In summary, this study indicated that PTH1-34 plus MK-4 combination therapy accelerated bone formation and angiogenesis in calvarial bone defects in presence of osteopenia.

Large fungating basal cell carcinoma of the dorsum of the foot: A case report.

Basal cell carcinoma is the most common skin cancer, but may present as anatomically and pathologically unique variants. A careful understanding of the pathophysiology, meticulous preoperative planning, and the use of unique reconstructive techniques to preserve function and cosmesis are key in achieving a satisfactory oncologic result.

Evolution in the surgical management of gastric cancer: is extended lymph node dissection back in vogue in the USA?

BACKGROUND: Gastric cancer remains a formidable treatment challenge. For decades, treatment consisted mostly of surgical intervention for this deadly disease. With improvements in the multi-disciplinary management of solid organ malignancies, the approach to this disease is being stepwise refined. MAIN BODY: One of the prevalent controversies in the surgical management of gastric cancer rests on the need for adequate harvesting of lymph nodes. For decades, lymph node dissection is regarded as a staging technique useful in only upstaging the disease. The adoption of D2 lymphadenectomy has been particularly slow to mature. But with prevailing data from Asia consistently demonstrating a survival benefit from lymphadenectomy, it calls into question the notion of lymphadenectomy as being solely a staging procedure. CONCLUSIONS: As gastric resection techniques are being better defined in western countries and surgical morbidities lowered on its execution, D2 lymphadenectomy is becoming more accepted as the new standard in the management of gastric cancer.

LGR4 Is a Direct Target of MicroRNA-34a and Modulates the Proliferation and Migration of Retinal Pigment Epithelial ARPE-19 Cells.

The pathology of proliferative vitreoretinopathy and proliferative diabetic retinopathy is linked to proliferation, migration, and adhesion of the retinal pigment epithelium. MicroRNA-34a (miR-34a) expression modulates changes in proliferation and migration of retinal pigment epithelial cell line ARPE-19. In this study, we determined that miR-34a interacts with LGR4, identified by bioinformatics using TargetScan Human 5.0, to affect these changes. Double luciferase gene reporter assay confirmed miR-34a involvement in mediating control. miR-34a mimic transfection decreased LGR4 expression. Western blot analysis documented corresponding protein expression inhibition. MTS, Ki67 immunostaining, scratch and transwell testing, along with attachment assay showed that miR-34a upregulation inhibited ARPE-19 cell proliferation, migration and attachment partly through downregulation of LGR4 protein expression. Western blot analysis revealed that both miR-34a upregulation and LGR4 downregulation induced declines in E2F1, p-CDC2, CDK2, CDK4 and CDK6 protein expression. Taken together, miR-34a gene expression upregulation inhibits ARPE-19 cell proliferation, migration and adhesion partly by suppressing LGR4 expression. These results substantiate earlier indications that both miR-34a and LGR4 are potential drug targets to prevent fibrosis in a clinical setting.

MicroRNA-206: Effective Inhibition of Gastric Cancer Progression through the c-Met Pathway.

MicroRNAs are endogenous short chain nucleotide RNAs that regulate gene function by direct binding of target mRNAs. In this study, we investigated the effects of microRNA-206 (miR-206) on the development of gastric cancer. miR-206 was first confirmed to be downregulated in gastric cancer specimens. Conversely, upregulation of c-Met was confirmed in tissue samples of human gastric cancer, with its level inversely correlated with miR-206 expression. Introduction of miR-206 inhibited cellular proliferation by inducing G1 cell cycle arrest, as well as migration and invasion. Moreover, important proliferation and/or migration related molecules such as c-Met, CDK4, p-Rb, p-Akt and p-ERK were confirmed to be downregulated by Western blot analysis. Targeting of c-Met also directly affected AGS cell proliferation, migration and invasion. In vivo, miR-206 expressing tumor cells also displayed growth delay in comparison to unaffected tumor cells. Our results demonstrated that miR-206 suppressed c-Met expression in gastric cancer and could function as a potent tumor suppressor in c-Met overexpressing tumors. Inhibition of miR-206 function could contribute to aberrant cell proliferation and migration, leading to gastric cancer development.

Targeted deletion of the murine Lgr4 gene decreases lens epithelial cell resistance to oxidative stress and induces age-related cataract formation.

Oxidative stress contributes to the formation of cataracts. The leucine rich repeat containing G protein-coupled receptor 4 (LGR4, also known as GPR48), is important in many developmental processes. Since deletion of Lgr4 has previously been shown to lead to cataract formation in mice, we sought to determine the specific role that Lgr4 plays in the formation of cataracts. Initially, the lens opacities of Lgr4(-/-) mice at different ages without ocular anterior segment dysgenesis (ASD) were evaluated with slit-lamp biomicroscopy. Lenses from both Lgr4(-/-) and wild-type mice were subjected to oxidation induced protein denaturation to assess the ability of the lens to withstand oxidation. The expression of antioxidant enzymes was evaluated with real-time quantitative PCR. Phenotypically, Lgr4(-/-) mice showed earlier onset of lens opacification and higher incidence of cataract formation compared with wild-type mice of similar age. In addition, Lgr4(-/-) mice demonstrated increased sensitivity to environmental oxidative damage, as evidenced by altered protein expression. Real-time quantitative PCR showed that two prominent antioxidant defense enzymes, catalase (CAT) and superoxidase dismutase-1 (SOD1), were significantly decreased in the lens epithelial cells of Lgr4(-/-) mice. Our results suggest that the deletion of Lgr4 can lead to premature cataract formation, as well as progressive deterioration with aging. Oxidative stress and altered expression of several antioxidant defense enzymes contribute to the formation of cataracts.

Management of afferent loop obstruction from recurrent metastatic pancreatic cancer using a venting gastrojejunostomy.

Pancreatic cancer is an aggressive malignancy potentially curable with surgical intervention. Following pancreaticoduodenectomy for suspected pancreatic head malignancy, patients have a high risk for both immediate and delayed problems due to surgical complications and recurrent disease. We report here a patient with pancreatic cancer treated with pancreaticoduodenectomy who developed recurrent disease resulting in obstruction of the afferent limb. The patient developed biliary obstruction and cholangitis at presentation. Her biliary tree failed to dilate which precluded safe percutaneous biliary decompression. During surgical exploration, she was found to have a dilated afferent limb at the level of the transverse mesocolon. The patient underwent decompression of the afferent limb as well as the biliary tree using a venting gastrojejunostomy to the blind loop. This represents a novel surgical approach for management of this complicated and difficult problem.

Inhibitory effect of microRNA-34a on retinal pigment epithelial cell proliferation and migration.

PURPOSE: Retinal pigment epithelial (RPE) cells play important roles in ophthalmologic diseases such as proliferative vitreoretinopathy, AMD, and diabetic retinopathy. MicroRNA-34a (miR-34a) has been reported to be important in the regulation of cell proliferation, migration, differentiation, and apoptosis. In this study, we explored the effects of miR-34a on RPE cells. METHODS: The expression level of miR-34a in subconfluent and postconfluent ARPE-19 cells was investigated with quantitative real-time PCR. MicroRNA mimic and small interfering RNA (siRNA) were transiently transfected into RPE cells. Transfected RPE cells were analyzed with WST-1 proliferation assay, and their migration was analyzed with transwell assay and in vitro scratch study. The expression or activation of target proteins was detected by Western blotting. RESULTS: MicroRNA-34a was significantly downregulated in subconfluent ARPE-19 cells compared with postconfluent cells. Introduction of miR-34a inhibited the proliferation and migratory ability of RPE cells without obvious cell apoptosis. In miR-34a transfected cells, many important proliferation and/or migration related molecules such as c-Met, CDK2, CDK4, CDK6, E2F1, and phosphorylated-Cdc2 (p-Cdc2) were downregulated. Small interfering RNA designed to target c-Met also inhibited the proliferation and migration of RPE cells and downregulated CDK2, CDK6, E2F1, and p-Cdc2. CONCLUSIONS: MicroRNA-34a is downregulated in subconfluent RPE cells. MicroRNA-34a can inhibit the proliferation and migration of RPE cells through downregulation of its targets c-Met and other cell cycle-related molecules. Our results indicated that miR-34a is involved in the regulation of RPE cells.

MicroRNA-124a is epigenetically regulated and acts as a tumor suppressor by controlling multiple targets in uveal melanoma.

PURPOSE: MicroRNA-124a (miR-124a), an abundant microRNA in the central neuron system, has been linked to tumor progression. Here, we investigated the role of miR-124a in uveal melanoma development. METHODS: Expression of miR-124a in uveal melanoma cells was examined using real time RT-PCR. The effect of miR-124a on cell proliferation, migration, and invasion was analyzed using MTS assay, flow cytometry, and transwell experiments. The ability of miR-124a to repress tumor growth was tested in vivo. Target genes of miR-124a were first predicted by bioinformatics, confirmed using a luciferase assay, and their expression determined by Western blotting. DNA methylation and histone modification of miR-124a was analyzed by methylation-specific PCR and ChIP assay. Finally, epigenetic drugs were used to alter the expression of miR-124a. RESULTS: miR-124a expression was downregulated in both uveal melanoma cells and clinical specimens. Transient transfection of miR-124a into uveal melanoma cells inhibited cell growth, migration, and invasion. Moreover, introduction of miR-124a suppressed in vivo growth of tumor. Potential targets of miR-124a were found to include CDK4, CDK6, cyclin D2, and EZH2. Knockdown of EZH2 by siRNA resulted in inhibition of uveal melanoma cell migration and invasion. In addition, miR-124a expression was found to be regulated via epigenetic mechanisms, with its expression restored when cells were treated with a DNA hypomethylating agent, 5-aza-2'-deoxycytidine, and a histone deacetylase inhibitor, trichostatin A. CONCLUSIONS: Our results demonstrated that miR-124a could function as a potent tumor suppressor by regulation of multiple targets, and was epigenetically silenced in the development of uveal melanoma.