NON-INVASIVE THORACOABDOMINAL MAPPING OF POST-ESOPHAGECTOMY GASTRIC CONDUIT FUNCTION USING GASTRIC ALIMETRY®

Background
The aim of this study was to assess the association between interval between nCRT and
surgery and oncological and surgical outcomes in esophageal cancer patients.

Methods:
Pubmed, Embase and Cochrane data base were searched to identify eligible studies from
their inception to December 31, 2021 and divided into early and delayed surgery group. A
total of 19 studies with 12 retrospective cohort study, one randomized control trial and 6
data base registry study were included. A total of 13600 participants with 6395 participants
in early group and 7205 participants in delayed group were analyzed.

Results:
Pooled analysis of cohort studies comparing delayed surgery versus early surgery
showed no difference in OS (Hazard ratio (HR) 1.03 95% CI 0.91,1.16), pCR rate(Odds
Ratio (OR) 0.98, 95% CI 0.80, 1.20), R0 resection rate(OR 0.90, 95% CI 0.55, I.45;
I2=43%), perioperative mortality(OR1.03, 95% CI 0.59, 1.77; I2=0%), pulmonary (OR 1.26
95% CI 0.97,1.64; I2=22%) or major complication rate (OR 1.29, 95% CI 0.96, 1.73;
I2=29%) but was however associated with an increased anastomotic leak rate(OR 1.48,
95%CI 1.11,1.97). Mean while pooled assessment of data base registry studies showed
Delayed surgery resulted in increased pCR rate (OR 1.12, 95%CI 1.01, 1.24) which
however failed to translate to increased overall survival(HR 1.01, 95%CI 0.92 , 1.10; I2
=0%). But delayed surgery was associated with increased perioperative mortality(OR 1.35,
95% CI 1.07, 1.69; I2=15%), and major complication rate (OR 1.55; 95% CI 1.20, 2.01 I2=
26%)compared to early surgery.
Conclusion:
Delayed surgery produces equivalent oncological and surgical outcome except increased
anastomotic leak rates in high volume center. However, the result should be interpreted
with caution because of contradictory results between cohort studies and data base
registry studies.

Introduction
Conversion gastrectomy is increasingly being considered for gastric cancer peritoneal metastases (GCPM) patients who have good response to intraperitoneal paclitaxel (IP-PTX) with systemic therapy. However, the outcomes of surgery are unclear. Our study aimed to evaluate surgical outcomes and prognostic factors for conversion surgery.
Methods
Patients with GCPM were recruited for a prospective phase II trial and received IP-PTX with oral capecitabine and intravenous oxaliplatin (XELOX) in 21-day cycles. Those with good response to chemotherapy, had negative peritoneal fluid cytology with no extraperitoneal metastases and no carcinomatosis peritonei on re-look diagnostic laparoscopy underwent conversion gastrectomy. Primary outcome was overall survival (OS) and secondary endpoint were morbidity and especially those with Clavien-Dindo IIIb & Above.
Results
Of 64 patients with synchronous GCPM, 20 (31.3%) underwent conversion gastrectomy. Median operative time was 316 minutes (IQR 279-368) and median length of stay was 9 days (IQR 7-15). Distal gastrectomy was performed in 45% (9/20) while 55% (11/20) underwent total gastrectomy, with 85% (17/20) performed as open procedure. No combined organ resection or 30-day mortality was noted. Median lymph node harvest was 37 (IQR 23-44) and R0 resection margin was achieved in 65% (13/20) of patients but did not significantly influence median OS (R0 vs. R1-2, median OS; 29.5 vs. 20.7 months, p=0.442). Overall morbidity was 35% (7/20) & major morbidity reported in 10% (2/20) of patients who underwent re-operation for duodenal stump leak and bleeding. The overall 12-month OS was 85% and 24-months OS was 50%. Patients with poorer response to pre-operative therapy (tumour response grading [TRG] <3, p=0.082) and presence of LVI (p=0.057) were found to be associated with OS <24 months although significance was not reached. On survival analysis, median OS for patients with good response to pre-operative treatment (TRG <3) and those who did not (TRG=3) were 28.1 months and 16.0 months respectively (TRG<3, HR 0.085, 95% CI 0.016-0.44).
Conclusions
Conversion gastrectomy is a safe and feasible option for select GCPM patients following IP-PTX with systemic treatment. Response to pre-operative treatment was a significant predictor in overall survival after conversion surgery.

Background
Endoscopic sleeve gastroplasty (ESG) is a minimally invasive intervention to address obesity and associated comorbidities. Previous studies have shown variable outcomes following bariatric surgery for patients who are privately insured, publicly insured, or self-pay. Differences include higher excess weight loss (%EWL) and earlier loss to follow up in self-pay patients, with variability in comorbidity resolution and complications. In this study we aim to review our institutional outcomes following ESG by payer.

Methods
A retrospective review of a prospective bariatric quality database included all patients who underwent ESG between 6/2016 and 10/2022 at a single institution. Post-procedure outcomes, including %EWL, comorbidity resolution, and complications were collected and compared by payer status. Group comparisons were made using two-tailed Wilcoxon rank-sum and Fisher’s exact test.

Results
During the study period, 57 patients underwent ESG; 22 (38.6%) were insured and 35 (61.4%) were self-pay. Of the 22 insured patients, 16 (72.7%) were MERIT trial participants and 6 (27.3%) were privately insured. There were no significant demographic differences between the three groups, including starting BMI. Comorbidities differed in more hypertensive trial patients compared to privately insured patients (56.3% vs 0%, p=0.027) and more diabetic trial patients compared to self-pay or privately insured patients (37.5% vs 8.6% vs 0%, p=0.025). Preoperative rates of smoking, hyperlipidemia, obstructive sleep apnea and GERD did not differ significantly between groups. There were no significant differences in number of endosutures, OR time, estimated blood loss, length of stay, postoperative hemorrhage, return to OR, or 30-day outcomes including ED visits, readmission, death, or treatment for dehydration between groups. Trial participants had significantly longer median follow-up at 29 months compared to 9 months for private insurance and 6 months for self-pay, p=0.001. Median %EWL was greater in insured patients (n=4, all MERIT trial) compared to self-pay patients (n=4) at the 4-year postoperative timepoint only (-39.2±20.6% vs +9.4±14.0%, p=0.021). Self-pay patients had weight regain beyond consultation weight at the 4-year postoperative timepoint [Fig 1]. There were no statistically significant differences in HbA1c, diabetes, obstructive sleep apnea, GERD, hyperlipidemia, or hypertension between groups at 6-month, 1-year, 2-year, or 3-year postoperative timepoints.

Conclusion
Following ESG, excess weight loss is sustained up to 2-years postop regardless of payer, and up to 4-years postop in insured patients. Differences in %EWL by payer may include more sustained %EWL at 4-year postop in insured patients than in self-pay patients.

Purpose: Since 2011, nationally-recognized guidelines have recommended the use of intraoperative esophagogastroduodenoscopy (iEGD) during minimally invasive heller myotomy (MHM) to detect intraoperative leaks and prevent esophageal narrowing. Data regarding the application of these guidelines have not been reported. The purpose of this study is to evaluate the frequency of guideline adherence and rates of complications in patients undergoing MHM with and without iEGD.
Methods: The 2011-2020 National Surgical Quality Improvement Program (NSQIP) registry was utilized to evaluate patients undergoing MHM with or without iEGD. Trends, perioperative outcomes, and 30-day complications were examined using univariable analysis and multivariable regression.
Results: A total of 4,631 MHM patients were identified; 895 (19.3%) with concomitant iEGD, and 3735 (80.7%) without iEGD. Patient demographics including age, body mass index, gender, and race/ethnicity were similar between groups (all p>0.05). In patient undergoing iEGD, operative time was longer 150 ± 65 minutes vs 137 ± 58 minutes (p<0.001), but there was no difference in mean length of stay 2.0 ± 2.7 days vs 1.7 ± 4.1 days (p=0.052), or overall complication rate 50 (5.6%) vs 197 (5.3%) (p=0.708). The frequency of iEGD during MHM did not increase during the study period (Figure 1, p=0.658). Postoperatively, fewer iEGD patients suffered from pneumonia 2 (0.2%) vs 36 (1.0%), p=0.027, which remained statistically significant after multivariable regression (OR 0.191, 95% CI 0.045-0.808, p=0.024).
Conclusion: Despite 10 years of national guidelines encouraging the use of intraoperative EGD during minimally invasive heller myotomy, practice patterns have not appeared to change. This robust database of 30-day outcomes suggests iEGD is associated with decreased postoperative pneumonia, so further efforts to promote adherence to the guidelines may be warranted.

Introduction
Esophagectomy is a complex procedure performed for malignant and benign conditions. Procedural variations exist (including open vs laparoscopic vs robotic, two-stage Ivor-Lewis vs three-stage McKeown), but all involve the formation of a largely-thoracic gastric conduit. These may be associated with conduit dysfunction, early and/or persistent delayed gastric emptying, reflux and pain with no mechanical cause. There is emerging evidence that gastric electrical abnormalities contribute to this conduit dysfunction. A non-invasive medical device for body surface gastric mapping (BSGM) was recently developed to evaluate gastric electrical activity and function. This study aims to assess the feasibility of the novel BSGM device in the post-oesophagectomy stomach.

Methods
Patients who had undergone an esophagectomy at Auckland City Hospital (Auckland, New Zealand) between 2017-2022 were recruited following ethics approval. Exclusions comprised of patients undergoing adjuvant therapy or mechanical obstructions. The Gastric Alimetry System® (Auckland, New Zealand) was employed, comprising a stretchable array (8x8 electrodes; 196cm²) and cloud-based analytics platform. Following an overnight fast, 30 minutes of baseline recording was performed, followed by a meal challenge and 4 hours of post-prandial recordings. Symptoms were logged on a validated App. Spectral analysis of BSGM data was performed, with quantitative analysis including gastric frequency, BMI-adjusted amplitude, Gastric Alimetry Rhythm Index (a measure of rhythm stability) and meal response, compared to reference intervals in 110 healthy volunteers. Adverse events were also recorded.

Results
6 patients were recruited, including one who subsequently had a total gastrectomy and colonic interposition. Array placement was based on post-operative cross-sectional imaging. Only one patient was symptomatic during the session, with nausea, pain and early satiation. Gastric activity was successfully captured in all patients except the patient who had the colonic interposition (negative control), having no discernible gastric activity. 4/5 patients with gastric conduits showed abnormalities on Gastric Alimetry: 3 with low amplitude activity (<22μV), 3 had low gastric frequency (<2.65 cycles/min), 2 had low Gastric Alimetry Rhythm Index associated with unstable pacemaking. There were no adverse events.

Conclusion
Gastric Alimetry is a safe and feasible technique to non-invasively assess the gastric myoelectrical activity and motility following esophagectomy, identifying changes in gastric function. The significance for the management of post-oesophagectomy gastric dysfunction can now be evaluated.