Loosening the belt on magnetic sphincter augmentation indications: does body mass index matter?

BACKGROUND: Magnetic sphincter augmentation (MSA) is an effective treatment for gastroesophageal reflux disease (GERD). However, the impact of obesity on MSA outcomes is unknown. The objective of this study was to evaluate the effectiveness of MSA in patients with GERD and obesity. METHODS: A retrospective cohort study was performed of consecutive patients who underwent laparoscopic MSA at three high-volume centers from 2016 to 2019. Patients were grouped into four cohorts according to the World Health Organization body mass index (BMI) classification: BMI < 25 (normal weight), BMI 25-29.9 (overweight), BMI 30-34.9 (obese class I), and BMI > 35 (obese class II-III). Preoperative, operative, and postoperative data were compared between groups. RESULTS: A total of 621 patients underwent laparoscopic MSA during the study period. Follow-up with endoscopy or video esophagram was available for 361 patients (58%) with a median follow-up of 15.4 months. Baseline characteristics of the groups were similar except the BMI > 35 group had more females and a higher preoperative median DeMeester score. There were no significant differences in outcomes between normal weight, overweight, and obese patient groups undergoing MSA. All groups experienced significant reductions in acid suppressive medication use, low GERD-HRQL scores, low DeMeester scores, few intraoperative and postoperative complications, and low rates of hiatal hernia recurrence after MSA. CONCLUSIONS: Magnetic sphincter augmentation is safe and effective in improving GERD symptoms, reducing esophageal acid exposure, and preventing hiatal hernia recurrence, irrespective of patient BMI. MSA should be considered an acceptable treatment option for obese patients with GERD.

Understanding the GERD Barrier.

Gastroesophageal reflux disease (GERD) is steadily increasing in incidence and now affects 18% to 28% of the population in the United States. A thorough understanding of the pathophysiology underlying this disease is necessary to improve the current standard of care. Most GERD pathophysiology models focus on the lower esophageal sphincter (LES) as the key element which prevents esophageal reflux. More recent research has highlighted the crural diaphragm (CD) as an additional critical component of the GERD barrier. We now know that the CD actively relaxes when the distal esophagus is distended and contracts when the stomach is distended. Crural myotomy in animal models increases esophageal acid exposure, highlighting the CD's vital role. There are also multiple physiological studies in patients with symptomatic hiatal hernia that demonstrate CD dysfunction is associated with GERD. Finally, computer models integrating physiological data predict that the CD and the LES each contribute roughly 50% to the GERD barrier. This more robust understanding has implications for future procedural management of GERD. Specifically, effective GERD management mandates repair of the CD and reinforcement of the LES. Given the high rate of hiatal hernia recurrences, it seems that novel antireflux procedures should target this essential component of the GERD barrier. Future research should focus on methods to maintain crural integrity, decrease hiatal hernia recurrence, and improve long-term competency of the GERD barrier.

Less is more: cruroplasty alone is sufficient for revisional hiatal hernia surgery.

BACKGROUND: Recurrence of hiatal hernia after anti-reflux surgery is common, with past studies reporting recurrence rates of 10-15%. Most patients experience relief from GERD symptoms following initial repair; however, those suffering from recurrence can have symptoms severe enough to warrant another operation. Although the standard of care is to revise the fundoplication or convert to magnetic sphincter augmentation (MSA) in addition to redo cruroplasty, it stands to reason that with an intact fundoplication, a repeat cruroplasty is all that is necessary to alleviate the patients' symptoms. In other words, only fix that which is broken. METHODS: A retrospective review of patients with symptomatic hiatal hernia recurrence who underwent reoperation between January 2011 and September 2018 was conducted. Patients who received revisional cruroplasty alone were compared with cruroplasty plus some other revision (fundoplication revision, or takedown and MSA placement). Demographics, operative details, and postoperative outcomes were collected. RESULTS: There were 73 patients identified. Median time to recurrence after the first procedure was 3.7 (1.9-8.2) years. Thirty-two percent of the patients had GERD symptoms for more than 10 years. Twenty-six patients underwent cruroplasty only. Forty-seven patients underwent cruroplasty plus fundoplication revision. There were no significant differences in operative times (2.4 h cruroplasty alone, 2.8 h full revision, p = 0.75) or postoperative complications between the two groups. Patients had a mean follow-up time of 1.64 years. Of the 73 patients, 8 had subsequent hiatal hernia recurrence. The recurrence rate for patients with cruroplasty alone was 11%, and the recurrence rate for the full revision group was 12% (p = 1.00). CONCLUSION: Leaving an intact fundoplication alone at the time of revisional surgery did not adversely affect surgical outcomes. This data suggests a role for hernia-only repair for recurrent hiatal hernias.

Regression of Barrett's esophagus after magnetic sphincter augmentation: intermediate-term results.

BACKGROUND: Untreated gastroesophageal reflux disease (GERD) can lead to Barrett's esophagus and an increased risk for esophageal adenocarcinoma. Magnetic sphincter augmentation (MSA) is a safe and effective modality for the treatment of GERD. Preliminary research on short-term outcomes after MSA demonstrated significant regression of Barrett's. Further investigation is required to evaluate the long-term effect of this treatment. METHODS: A retrospective review of patients was conducted with biopsy-proven Barrett's esophagus who underwent MSA between 2007 and 2019. As a part of their preoperative evaluation, patients underwent esophagogastroduodenoscopy (EGD) with biopsies of the distal esophagus and gastroesophageal junction including any abnormal-appearing segments, pH testing, and a videoesophagram. Patients were categorized according to the length of Barrett's identified (ultrashort < 1 cm, short 1-3 cm, long > 3 cm). Improvement was defined as a decrease in length (e.g. long to short). RESULTS: There were 87 patients identified for study inclusion. 55 patients were male. The median body mass index was 26.95. The median age was 61.81 (49.79-68.29). Mean follow-up time was 2.35 ± (1.57) years. 7 (8.0%) of these patients began with long segment Barrett's, 58 (66.7%) began with short segment disease, and 22 (25.3%) began with an ultrashort segment. Within this cohort, 74 (85.06%) had undergone postoperative biopsy. 7 out of 74 patients (9.46%) showed improvement in their intestinal metaplasia and 45/74 (60.81%) showed complete regression. Fisher's exact test showed a significant decrease in Barrett's length following MSA (p = 0.002). No patients progressed to dysplasia or neoplasia. There was a statistically significant decrease in the median Demeester score from 34.00 to 13.70 after surgery (p < .001). CONCLUSION: MSA reduces esophageal acid exposure and can lead to reduction or resolution of Barrett's esophagus. MSA is also effective at preventing progression of metaplasia to dysplasia or neoplasia. This effect remains consistent even after 2 years of follow-up.

Magnetic sphincter augmentation with hiatal hernia repair: long term outcomes.

INTRODUCTION: Magnetic sphincter augmentation (MSA) is a safe and effective treatment for patients with gastroesophageal reflux disease (GERD). MSA was initially indicated for patients with GERD and concomitant hiatal hernias < 3 cm. However, excellent short- and intermediate-term outcomes following MSA and hiatal hernia repair in patients with hiatal hernias ≥ 3 cm have been reported. The purpose of this study is to assess long-term outcomes for this patient population. METHODS AND PROCEDURES: A retrospective review was performed of patients with GERD and hiatal hernias ≥ 3 cm who underwent MSA and hiatal hernia repair. Patients were treated at two tertiary medical centers between May 2009 and December 2016. Follow up included annual video esophagram, upper endoscopy, or both. Outcomes included pre- and post-operative GERD health-related quality of life (GERD-HRQL) scores, length and regression of Barrett's esophagus, resolution of esophagitis, need for endoscopic dilations or implant removal, and clinically significant hiatal hernia recurrence (> 2 cm) on videoesophagram or endoscopy. RESULTS: Seventy-nine patients (53% female) with a median age of 65.56 (58.42-69.80) years were included. Median follow up was 2.98 (interquartile range 1.90-3.32) years. Median DeMeester scores decreased from 42.45 (29.12-60.73) to 9.10 (3.05-24.30) (p < 0.001). Severity of esophagitis (e.g. LA class C to class B) significantly improved (p < 0.01). Forty percent of patients with Barrett's esophagus experienced regression (p < 0.01). Median GERD-HRQL scores improved from 21 to 2. Five (6.3%) hiatal hernia recurrences occurred, and 1 required re-operation. Age, body mass index, size of the initial hiatal hernia, and sex had no significant effect on whether a patient developed a recurrence. CONCLUSIONS: Magnetic sphincter augmentation in conjunction with large hiatal hernia repairs for patients with GERD achieves excellent long-term radiographic and clinical results, and a low overall need for reoperation, without the need for mesh.

Safety and efficacy of magnetic sphincter augmentation dilation.

BACKGROUND: The magnetic sphincter augmentation device (MSA) provides effective relief of gastroesophageal reflux symptoms. Dysphagia after MSA implantation sometimes prompts endoscopic dilation. The manufacturer's instructions are that it be performed 6 or more weeks after implantation under fluoroscopic guidance to not more than 15 mm keeping 3 or more beads closed. The purpose of this study was to assess adherence to these recommendations and explore the techniques used and outcomes after MSA dilation. METHODS AND PROCEDURES: We conducted a multicenter retrospective review of patients undergoing dilation for dysphagia after MSA placement from 2012 to 2018. RESULTS: A total of 144 patients underwent 245 dilations. The median size of MSA placed was 14 beads (range 12-17) and the median time to dilation was 175 days. A second dilation was performed in 67 patients, 22 patients had a third dilation and 7 patients underwent 4 or more dilations. In total, 17 devices (11.8%) were eventually explanted. The majority of dilations were performed with a balloon dilator (81%). The median dilator size was 18 mm and 73.4% were done with a dilator larger than 15 mm. There was no association between dilator size and need for subsequent dilation. Fluoroscopy was used in 28% of cases. There were no perforations or device erosions related to dilation. DISCUSSION: There is no clinical credence to the manufacturer's recommendation for the use of fluoroscopy and limitation to 15 mm when dilating a patient for dysphagia after MSA implantation. Use of a larger size dilator was not associated with perforation or device erosion, but also did not reduce the need for repeat dilation. Given this, we would recommend that the initial dilation for any size MSA device be done using a 15 mm through-the-scope balloon dilator. Dysphagia prompting dilation after MSA implantation is associated with nearly a 12% risk of device explantation.

Magnetic sphincter augmentation versus fundoplication for gastroesophageal reflux disease: pros and cons.

PURPOSE OF REVIEW: The purpose of this magnetic sphincter augmentation (MSA) year in review article is to provide a clear understanding for the current state of MSA literature in 2019, and contrast MSA outcomes with traditional fundoplication. RECENT FINDINGS: Continued work was performed in 2019 to expand patient populations eligible for MSA including those with hiatal hernia, post-bariatric patients, patients necessitating a thoracic approach, and patients with esophageal intestinal metaplasia. Additionally, a large systematic review reinforced earlier findings comparing laparoscopic fundoplication to MSA. This study demonstrated equivalency over many different operative outcomes, with MSA patients having less bloating while also retaining the ability to belch and vomit. Furthermore, independent research teams found a modest cost savings for MSA over laparoscopic fundoplication with budget analysis. SUMMARY: MSA is a safe and efficacious procedure originally approved for patients with medically refractory, uncomplicated gastroesophageal reflux disease. The accumulating body of evidence suggests patients with intestinal metaplasia or hiatal hernias can safely and effectively undergo MSA, whereas further research will be required before MSA is widely used for post-bariatric patients or for patients requiring a transthoracic surgical approach. MSA is equivalent or superior to laparoscopic fundoplication in all surgical outcomes measured thus far.

Multi-institutional outcomes using magnetic sphincter augmentation versus Nissen fundoplication for chronic gastroesophageal reflux disease.

BACKGROUND: Magnetic sphincter augmentation (MSA) has emerged as an alternative surgical treatment of gastroesophageal reflux disease (GERD). The safety and efficacy of MSA has been previously demonstrated, although adequate comparison to Nissen fundoplication (NF) is lacking, and required to validate the role of MSA in GERD management. METHODS: A multi-institutional retrospective cohort study of patients with GERD undergoing either MSA or NF. Comparisons were made at 1 year for the overall group and for a propensity-matched group. RESULTS: A total of 415 patients (201 MSA and 214 NF) underwent surgery. The groups were similar in age, gender, and GERD-HRQL scores but significantly different in preoperative obesity (32 vs. 40 %), dysphagia (27 vs. 39 %), DeMeester scores (34 vs. 39), presence of microscopic Barrett's (18 vs. 31 %) and hiatal hernia (55 vs. 69 %). At a minimum of 1-year follow-up, 354 patients (169 MSA and 185 NF) had significant improvement in GERD-HRQL scores (pre to post: 21-3 and 19-4). MSA patients had greater ability to belch (96 vs. 69 %) and vomit (95 vs. 43 %) with less gas bloat (47 vs. 59 %). Propensity-matched cases showed similar GERD-HRQL scores and the differences in ability to belch or vomit, and gas bloat persisted in favor of MSA. Mild dysphagia was higher for MSA (44 vs. 32 %). Resumption of daily PPIs was higher for MSA (24 vs. 12, p = 0.02) with similar patient-reported satisfaction rates. CONCLUSIONS: MSA for uncomplicated GERD achieves similar improvements in quality of life and symptomatic relief, with fewer side effects, but lower PPI elimination rates when compared to propensity-matched NF cases. In appropriate candidates, MSA is a valid alternative surgical treatment for GERD management.

Outcomes following laparoscopic transhiatal esophagectomy for esophageal cancer.

BACKGROUND: Most published minimally invasive esophagectomy techniques involve a multiple field approach, including laparoscopic and thoracoscopic esophageal mobilization. Laparoscopic transhiatal esophagectomy (LTE) should potentially reduce the complications associated with thoracotomy. This study aims to compare outcomes of LTE with open transhiatal esophagectomy (OTE) and en-bloc esophagectomy (EBE). METHODS: Retrospective chart review was performed on all patients who had an LTE for cancer between July 2008 and July 2012 at our institution. Data was compared with an historic cohort of patients who underwent OTE and EBE at the same institution from July 2002 to July 2008. RESULTS: There were 33 patients with LTE, compared with 60 patients with OTE and 139 with EBE. The presence of minor operative complications was similar (p = 0.36), but major complications were significantly less common in the LTE group (12, 23 and 33 %, respectively; p = 0.04). The median number of blood transfusions during hospitalization was significantly lower in the LTE group (0, 2.5 and 3, respectively; p = 0.005). Median tumor size was significantly smaller (1.5, 2.2, and 3 cm, respectively; p = 0.03), but the LTE group had a significantly higher percentage of patients with neoadjuvant treatment (39, 14 and 29 %, respectively; p = 0.008). Median lymph node yield for LTE was lower (24, 36 and 48, respectively; p < 0.0001), but the percentage of patients with positive nodes was similar (33, 33 and 39 %, respectively; p = 0.69). Mortality was equivalent among the groups (0, 2 and 4 %, respectively; p = 0.38). The median LOS for the LTE group was significantly lower (10, 13 and 15 days, respectively; p < 0.0001). Overall survival was not different between the three groups (p = 0.65), with median survival at 24 months of 70, 65 and 65 %, respectively. CONCLUSION: LTE can be performed safely with less major complications and shorter hospital stay than open esophagectomy. The reduced lymph-node harvest did not impact overall survival.

Lower Rates of Unplanned Conversion to Open in Robotic Approach to Esophagectomy for Cancer.

BACKGROUND: Minimally invasive approaches to esophagectomy have gained popularity worldwide; however, unplanned conversion to an open approach is not uncommon. This study sought to investigate risk factors associated with converting to an open approach and to evaluate outcomes following conversion. METHODS: Patients undergoing minimally invasive esophagectomy (MIE) for cancer were identified using the 2016-2019 Procedure Targeted NSQIP Database. Multivariable, stepwise logistic regression analysis was performed to investigate factors associated with unplanned conversion to open esophagectomy. Propensity-matched comparison of robotic (RAMIE) to traditional MIE was performed. RESULTS: A total of 1347 patients were included; 140 patients (10%) underwent conversion to open. Morbid obesity, diabetes, hypertension, American Society of Anesthesiologists class, and squamous cell carcinoma were associated with a higher likelihood of conversion. A robotic approach was associated with a lower likelihood of conversion to open (OR .57, 95% CI 0.32-.99). On multivariable analysis, squamous cell carcinoma pathology was the only variable independently associated with higher odds of conversion (OR 2.66, 95% CI 1.02-6.98). Propensity-matched comparison of RAMIE vs MIE showed no significant difference in conversion rate (6.5% vs 9.1%, P = .298), morbidity, or mortality. DISCUSSION: A robotic approach to esophagectomy was associated with a lower likelihood of unplanned conversion to open, and patients who were converted to open experienced worse outcomes. Future studies should aim to determine why a robotic esophagectomy approach may lead to fewer open conversions as it may be an underappreciated benefit of this newest operative approach.

Safety and efficacy of robotic-assisted groin hernia repair.

Robotic surgical technology has grown in popularity and applicability, since its conception with emerging uses in general surgery. The robot's contribution of increased stability and dexterity may be beneficial in technically challenging surgeries, namely, inguinal hernia repair. The aim of this project is to contribute to the growing body of literature on robotic technology for inguinal hernia repair (RIHR) by sharing our experience with RIHR at a large, academic institution. We performed a retrospective chart review spanning from March 2015 to April 2018 on all patients who had undergone RIHR at our university hospital. Extracted data include preoperative demographics, operative features, and postoperative outcomes. Data were analyzed with particular focus on complications, including hernia recurrence. A total of 43 patients were included, 40 of which were male. Mean patient age was 56 (range 18-85 years) and mean patient BMI was 26.4 (range 17.5-42.3). Bilateral hernias were diagnosed in 13 patients. All of the patients received transabdominal approaches, and all but one received placement of synthetic polypropylene mesh. There was variety in mesh placement with 23 patients receiving suture fixation and 14 receiving tack fixation. Several patients received a combination of suture, tacks, and surgical glue. Mean patient in-room time was 4.0 h, mean operative time was 2.9 h, and mean robotic dock time was 2.0 h. Regarding intraoperative complications, there was one bladder injury, which was discovered intraoperatively and repaired primarily. Same-day discharges were achieved in 32 patients (74.4%) of patients. One patient was admitted overnight for management of urinary retention. Additional ten patients were admitted for observation. Post-operatively, none of the cases resulted in wound infections. Eleven patients developed seromas and one patient was diagnosed with a groin hematoma. Median follow-up was 37.5 days, and one recurrence was reported during this time. The recurrent hernia in this case was initially discovered during a separate case and was repaired with temporary mesh. The use of the robot is safe and effective and should be considered an acceptable approach to inguinal hernia repair. Future prospective studies will help define which patients will benefit most from this technology.

Targeting PARP-1 allosteric regulation offers therapeutic potential against cancer.

PARP-1 is a nuclear protein that has important roles in maintenance of genomic integrity. During genotoxic stress, PARP-1 recruits to sites of DNA damage where PARP-1 domain architecture initiates catalytic activation and subsequent poly(ADP-ribose)-dependent DNA repair. PARP-1 inhibition is a promising new way to selectively target cancers harboring DNA repair deficiencies. However, current inhibitors target other PARPs, raising important questions about long-term off-target effects. Here, we propose a new strategy that targets PARP-1 allosteric regulation as a selective way of inhibiting PARP-1. We found that disruption of PARP-1 domain-domain contacts through mutagenesis held no cellular consequences on recruitment to DNA damage or a model system of transcriptional regulation, but prevented DNA-damage-dependent catalytic activation. Furthermore, PARP-1 mutant overexpression in a pancreatic cancer cell line (MIA PaCa-2) increased sensitivity to platinum-based anticancer agents. These results not only highlight the potential of a synergistic drug combination of allosteric PARP inhibitors with DNA-damaging agents in genomically unstable cancer cells (regardless of homologous recombination status), but also signify important applications of selective PARP-1 inhibition. Finally, the development of a high-throughput PARP-1 assay is described as a tool to promote discovery of novel PARP-1 selective inhibitors.

pp32 (ANP32A) expression inhibits pancreatic cancer cell growth and induces gemcitabine resistance by disrupting HuR binding to mRNAs.

The expression of protein phosphatase 32 (PP32, ANP32A) is low in poorly differentiated pancreatic cancers and is linked to the levels of HuR (ELAV1), a predictive marker for gemcitabine response. In pancreatic cancer cells, exogenous overexpression of pp32 inhibited cell growth, supporting its long-recognized role as a tumor suppressor in pancreatic cancer. In chemotherapeutic sensitivity screening assays, cells overexpressing pp32 were selectively resistant to the nucleoside analogs gemcitabine and cytarabine (ARA-C), but were sensitized to 5-fluorouracil; conversely, silencing pp32 in pancreatic cancer cells enhanced gemcitabine sensitivity. The cytoplasmic levels of pp32 increased after cancer cells are treated with certain stressors, including gemcitabine. pp32 overexpression reduced the association of HuR with the mRNA encoding the gemcitabine-metabolizing enzyme deoxycytidine kinase (dCK), causing a significant reduction in dCK protein levels. Similarly, ectopic pp32 expression caused a reduction in HuR binding of mRNAs encoding tumor-promoting proteins (e.g., VEGF and HuR), while silencing pp32 dramatically enhanced the binding of these mRNA targets. Low pp32 nuclear expression correlated with high-grade tumors and the presence of lymph node metastasis, as compared to patients' tumors with high nuclear pp32 expression. Although pp32 expression levels did not enhance the predictive power of cytoplasmic HuR status, nuclear pp32 levels and cytoplasmic HuR levels associated significantly in patient samples. Thus, we provide novel evidence that the tumor suppressor function of pp32 can be attributed to its ability to disrupt HuR binding to target mRNAs encoding key proteins for cancer cell survival and drug efficacy.