United States

Background:
Gastric cancer is among the top five cancer-burden in the United States and worldwide. The aim of our study is to investigate the racial variations in gastric carcinoma among individuals aged 50 years and above.

Methods:
We conducted a retrospective study using the SEER database, 17 registries, Nov 2021 Sub (2000- 2019) to identify individuals diagnosed with gastric cancer of 50 years and above age group. Age adjustment was done using the 2000 US population as a standard population. We collected racial/ethnic information related to incidence and incidence-based mortality of stomach cancer in our desired age groups.

Results:
This study included a total population of 109,352 patients of 50 years and above age with stomach cancer, out of which 71.6% were white, 12.9% were black, 14.2% were Asian or Pacific Islanders (API), and 0.9% were 1 American 1 Indian/ 1 Alaskan native (AI/AN). Based on incidence, all-cause mortality was 79.2% in white population, 78.9% in black, 71.5% in API and 82.8% in AI/AN. The incidence rate among white, black, API, and AI/AN were 20.6, 35, 36.3, and 21.3 per 100,000 population respectively, whereas the incidence-based mortality among the above races were 16.4, 28.9, 26.7, and 18.7 per 100,000 standard population. According to race, the incidence in white was 71.6% with incidence-based mortality of 79.2%. In Black incidence was 12.9% with incidence-based mortality of 78.9%. In American Indian incidence was 0.9% and incidence-based mortality was 82.8% and for Asian
incidence was 14.2% and incidence-based mortality of 71.5%.

Conclusion:
Our study outlines the racial disparities in the incidence and mortality of gastric carcinoma among individuals with gastric carcinoma among individuals aged 50 years and above. Although, gastric carcinoma is diagnosed mostly in the white population followed by Asian or Pacific islanders, black and then American Indians. The incidence rate and incidence-based mortality rates were highest among
Asian/Pacific Islanders and Black compared to that of white and American Indian/Alaskan natives. These findings help to address the disparities through interventions and healthcare policies targeted to improve gastric cancer incidence and outcomes across a diverse racial or ethnic population in the United
States. Further research is warranted to explore the underlying factors contributing to the racial disparities in gastric cancer.

AMA Research Challenge 2023

Racial Disparities in Incidence and Mortality of Gastric Carcinoma of Individuals
Aged 50 Years and Above: A Population-Based Analysis

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**Abstract:**



A Retrospective Cohort Study: Utility of Fecal Occult Blood Test in the Acute Hospital Setting and Its Clinical Impacts

Association Between Mucosa-Associated Lymphoid Tissue (MALT) Surgery and Inflammatory Bowel Disease (IBD): A Systematic Review

Association Between Mucosa-Associated Lymphoid Tissue (MALT)
Surgery and Inflammatory Bowel Disease (IBD): A Systematic Review

Background: Although low-energy pelvic fractures seldom present with significant hemorrhage, early recognition of at-risk patients is essential. We aimed to identify predictors of blood use in this cohort.
Methods: A 5-year retrospective chart review was performed. Low energy mechanism was defined as falls of ≤ 5 feet. Fracture pattern was assigned using the AO/OTA system as A, B or C. Primary outcome was the need for ≥ 2 units of packed red blood cells (PRBC) in the first 48 hours. Bivariable analysis and logistic regression analysis were performed. A p-value ≤0.05 was considered significant.
Results: 350 patients were included with median age 88 (interquartile range [IQR] 85-92) and median Injury Severity Score (ISS) 5 (IQR 4-8). 346 (99%) had type A fractures. 17 (5%) required ≥2U PRBC/48 hours. In-hospital mortality rate was 4%. Factors associated with blood transfusion were systolic blood pressure (SBP) < 100 mmHg at any time in the emergency department (ED), trauma team activation, Abdomen-Abbreviated Injury Score and contrast extravasation on computed tomographic (CT) scan. By logistic regression, SBP< 100 mmHg (odds ratio [OR] 16.3, 95% confidence interval [CI] 5.33-40.2) and contrast extravasation (OR 4.29, 95% CI 1.11-15.3) were predictors. Both need for 2U PRBC (4/17 [24%] vs 9/332 [3%], p=0.002) and any SBP < 100 mmHg in the ED (6/41 [15%] vs 7/307 [2%], p=0.001) were associated with mortality.
Conclusion: Contrast extravasation on CT and hypotension in the ED predicted the need for transfusion of ≥ 2U of PRBC in patients with low energy pelvic fractures.

Hypotension in the Emergency Department and Contrast Dye Extravasation Predict Blood Transfusion in Low-Energy Pelvic Fractures

Background
Phenytoin has demonstrated improved wound healing, as well as analgesic and antibacterial properties. These effects occur through a variety of mechanisms, including increased collagen deposition, neovascularization, and fibroblast proliferation secondary to an up-regulation in platelet-derived growth factor expression. Systemic absorption of phenytoin is negligible when administered topically. Since the application of phenytoin in wound care is relatively uncommon, a systematic review may provide meaningful insights for clinicians and researchers alike.

Methods
Cochrane Library, Pubmed, Pubmed Central, and Medline were searched to find all relevant studies. Secondary hand searching was done using the references listed in other relevant papers. Irrelevant papers were removed while screening titles and abstracts. Selected randomized controlled trials (RCTs) and non-randomized controlled trials (NRCTs) were assessed for quality using a revised tool for assessing risk of bias in randomized trials (RoB 2), and the Risk Of Bias In Non-randomized Studies - of Interventions (ROBINS-I) respectively. Data regarding the type of wounds studied, interventions, sample size, outcome measures, and reported adverse effects were collected and analyzed. 

Results
A total of 17 RCTs and 8 NRCTs were included. The wounds under study were predominantly of a single etiology; diabetic foot ulcers, decubitus ulcers, oral biopsy wounds, sutured episiotomies, leprotic ulcers, excisional wounds, fistulotomies, burns, abscess cavities, and traumatic wounds. A minority investigated wounds of multiple etiologies. Phenytoin was most often compared to inert controls such as normal saline, but there were trials with several other comparators including honey, silver sulfadiazine, Edinburgh University solution of lime, framycetin, and Aloe vera. The sample sizes of the included studies varied between 20 wounds to 200 wounds, with a median of 62 wounds. Phenytoin was found to hasten wound healing in the majority of trials. In addition, granulation tissue proliferation was improved, greater analgesic effects were produced, and there was an inhibition of bacterial contaminants as well as a reduction in wound discharge, slough, and exudates. Adverse effects were uncommon, minimal in severity, and transient in duration. The most common adverse effect observed was a burning sensation at the time of application.

Conclusion
Our review suggests that phenytoin may be a potentially beneficial adjunct to standard wound care. The topical administration of phenytoin can most likely be considered safe in most patients. We believe further study is warranted to investigate the optimal dose, frequency, and vehicle for application as well as the effects of phenytoin on other types of post-operative wounds.

Topical Phenytoin as an Adjunctive Treatment for Wounds

Background
Pancreatoduodenectomy (PD), an abdominal operation designed to remove pancreatic-head tumors, carries a substantial postoperative complication rate. Randomized data demonstrates that intraoperative fluid administration is associated with increased postoperative complications. However, it remains uncertain whether perioperative administration of crystalloids alone or in concert with colloids is more harmful. An initial literature search of [(Colloids versus crystalloids) OR (Crystalloids versus Colloids)] from 1987-2021 was performed on PubMed. Of the 116 eligible studies, 32(28%) concluded colloids are safer, 22(19%) concluded crystalloids are safer, and 62(53%) reached no consensus or determined equal efficacy. More importantly, only 16(13%) examined the effect of crystalloids vs colloids during hepatobiliary surgery, showing the lack of data. Therefore, we studied the relationship between volume and type of fluid administered during PD, specifically exploring intraoperative and 24 hours post-operative volume resuscitation.

Methods
We conducted a single-center retrospective analysis of patients undergoing PD from 2016-2021, for benign and malignant disease. Records were reviewed for patient demographic, disease, and treatment factors that include volume and type (crystalloid alone or combined with colloid) of fluid administered both intraoperatively and 24 hours post-operatively. The Clavien-Dindo complication score was calculated to determine if fluid ratios significantly affected patient outcome. Linear regression was performed to analyze the relationship between crystalloid administration and Clavien-Dindo score and ratio of crystalloid to colloid and Clavien-Dindo score.

Results
During the interval studies, there were 491 patients who underwent PD. 248(50%) were female, 366(74%) had a malignant preoperative diagnosis, and 176(36%) had preoperative chemotherapy. Median age was 65(range: 20-67) and average BMI was 25(range: 14.8-56). 212(43%) patients received solely perioperative crystalloid. There was no significant correlation between the amount of crystalloid administered and the Clavien-Dindo score (y=-0.0007841±0.002527,R^2:0.0006774,p:0.7568,F:0.09625). 276(56%) patients were administered ratios of perioperative crystalloid to colloid. There was a high positive significant correlation between ratio of crystalloid and colloid administered and the Clavien-Dindo score (y=0.7755±0.3955,R^2:0.01383,p:0.0509,F:3.844).

Conclusion
Based on a sample of 491 patients, increasing ratios of crystalloid to colloid appears to be significantly correlated with higher rates of complication in PD, as quantified by higher Clavien-Dindo scores. It is meaningful that patients who received any amount of colloid had worse outcomes. In future operative procedures, it may be necessary to balance crystalloid and colloid infusion or avoid colloid infusion to improve postoperative outcomes. Future work includes performing a multivariate analysis to see how other modifiable risk factors prior to PD can affect post-operative outcomes.

The Association of Total Volume and Ratio of Perioperative Crystalloid to Colloid Fluid Administration on Complications Following Pancreatoduodenectomy

Examining Discrepancies Between Preliminary and Final CT Readings for ED Admits After Hours and its Impact on Surgical Decision-Making: Results of a Pilot Study

Objective: Gabapentinoids are commonly prescribed to peripheral artery disease (PAD) for pain management. In this study, we investigate the impact of the history of gabapentinoids on postoperative risk of opioid-related disorders in PAD patients undergoing lower extremity bypass (LEB) Operation.

Methods: This is a retrospective propensity-score matched analysis of patients undergoing peripheral arterial bypass in TriNetX, a multicenter population-level database with 213 million patients from 92 health care organizations in the US. Two study groups were constituted based on the pre-surgical history of prescribed gabapentinoids. Group I comprised PAD patients who were using gabapentin or pregabalin prior to LEB. Group II comprised PAD patients who were not using either gabapentin or pregabalin prior to LEB. Patients with history of opioid-related disorders prior to LEB were excluded from the study. The patient population was matched (based on age, gender, and diabetes mellitus) using propensity score matching for balancing the groups and controlling for potential confounders. Primary outcomes were opioid-related disorders and mortality. The outcomes were reported at various time endpoints, and effect estimates were reported in odd ratios (OR) and 95% confidence intervals (CIs), p-values were calculated, and significance was set at p-value <0.05. 

Results: 
The study cohort included 14,602 patients after propensity-score matching. The Gabapentinoids group (n= 7,301) had 60.4% males and 39.6% females with a mean age of 65.8 years (SD ± 9.6). The No Gabapentinoids group (n=7,301) had 61.1% males and 38.9% females with a mean age of 65.6 years (SD ± 9.7). Primary outcomes showed a significantly increased 5-year risk for opioid-related disorders (5.1% vs 3.4% p<0.001). Logistic regression analysis controlling for 34 covariates and covariables showed statistically significant increase in the 5-year opioid-related disorders risk in patients with history of prescribed gabapentinoids (OR 1.426, CI [1.2, 1.7], p<0.001). Secondary analysis showed a dose-dependent increase in risk of 5-year opioid-related disorders in patients with history of gabapentin (Daily dose mg/day [%risk]: >0-300 mg/day [2.6%], >300-600mg/day [3.7%], >600-1200mg/day [6.3%], >1200-2400mg /day[6.6%], >2400 mg/day [8.4%], p<0.001) and composite 5% compared to 3.4% in the control group (p<0.001).

Conclusion: In patients undergoing lower extremity bypass with a history of prescribed gabapentin, there is an associated increased 5-year risk of opioid-related disorders in dose-dependent fashion. These results underscore the importance of identifying such patients to be at high risk for developing long-term opioid dependence which is associated with higher morbidity and mortality. There is a critical need for effective postoperative pain management planning and the involvement of the patient and other healthcare professionals in coordinating care to mitigate potential risks of opioid-related disorders. This study utilized population-level dataset that included electronic health records and claims data for patients covered with 99% of U.S. health plans which obviates the inherent biases associated with smaller datasets. Findings may not generalize worldwide as the study included only US patients.

History of Gabapentin Predisposes Patients to Risk of Opioid Use, Abuse and Dependence in Dose-Dependent Fashion

BACKGROUND: Incisional hernia (IH) is a common problem following abdominal wall closure after midline laparotomy. Prophylactic mesh placement has been advocated by many randomized controlled trials (RCTs). This meta-analysis seeks to define what population benefits the most from prophylactic mesh (PM) placement, what is the optimal position of PM (onlay vs. sublay), and what type of mesh is preferred (absorbable vs. non-absorbable). 

METHODS: A search of RCTs under PRISMA guidelines was conducted using keywords: mesh, prevention, laparotomy or abdominal surgery, and incisional hernia. 19 RCTs conducted in adults between 1990-2022 included the development of IH as the primary outcome.   

RESULTS: Pooled analysis of all patient populations found lower IH incidence when PM was used over primary fascial closure (PFC) (OR 2.69 [2.23-3.25]). On subgroup analysis, this trend remained true among patients undergoing AAA, bariatric, elective, & emergency surgeries. Both onlay (superficial to anterior rectus fascia) and sublay (deep to anterior rectus fascia) positions were associated with reduced IH risk when compared to PFC, with onlay mesh insignificantly favored over sublay (OR 0.68 [95% CI 0.39-1.19]). Additionally, both non-absorbable and absorbable mesh types demonstrated IH reduction over PFC, but no existing studies compared one mesh type over another. 

CONCLUSION: Prophylactic mesh closure is associated with a lower risk of incisional hernia after midline laparotomy when compared to primary fascial closure. Further research should examine the benefits of PM in other patient populations, specifically emergency operations with contaminated fields, as well as the utility of different mesh positions and mesh typing.

Prophylactic mesh reduces the risk of incisional hernia following midline laparotomy

Background 
Despite advances in surgical technique, perioperative management, and prophylaxis measures, post-discharge venous thromboembolism (pdVTE) remains a life-threatening complication following resection for pancreatic cancer (PC). While current guidelines recommend up to 28 days of thromboprophylaxis after discharge, it must be balanced with the risks of bleeding complications, and cost to the patient. Currently, prediction models to stratify patients by risk of developing pdVTE are limited in accuracy and therefore rarely used. Our preliminary analysis of five models revealed that simple logistic regression outperforms a range of higher-fidelity tree models and neural network models in stratifying patients by risk of developing pdVTE. We hypothesized this is likely due to the machine’s inability to overcome data bias and skewedness when predicting Low Incidence High Mortality (LIHM) post-operative complications. Our goal therefore, was to overcome this challenge by testing the utility of anomaly detection models (ADMs) in identifying patients at high risk of pdVTE after surgery for PC. 

Methods 
We analyzed data from all patients undergoing pancreatectomy for PC using the American College of Surgeons’ National Surgical Quality Improvement Program database from 2014 - 2021. We trained predictive models using 80% of the dataset and 213 input variables including demographics, clinical, laboratory, cancer and operation-specific variables. An unpenalized Logistic Regression (LR) model was used for baseline comparison. The ADMs deployed included Elliptical Envelope (EE), Isolation Forest (IF) and Local Outlier Factor (LOF). Due its low prevalence, pdVTE was defined as an “outlier” for the ADMs to identify amongst “normal” (non-VTE) patients. Models were tested on a 20% hold out dataset using Area-under-the-curve (AUC) scores. Sensitivity, specificity, negative predictive value and positive predictive value were also calculated and compared. 

Results 
A total of 53757 patients were included. The mean age was 63.6 ± 12.8 years, 50.0% were male, and 21,403 (39.8%) underwent Whipple procedures. A total of 1757 (3.3%) developed a pdVTE. In terms of model performance, IF and EE outperformed the LR in terms of both accuracy (Figure 1) and sensitivity. IF had a sensitivity of 0.60, followed by EE 0.57. LR had a sensitivity of 0.50. 

Conclusion 
ADMs provide superior outlier screening capability compared to traditional prediction models thereby bringing a promising opportunity to build risk stratification for LIHM complications such as pdVTE for patients with pancreatic cancer. 


Can Machine-Driven Anomaly Detection Models Identify Patients at Risk for Post-Discharge Venous Thromboembolism After Pancreatectomy for Pancreas Cancer?

Next from AMA Research Challenge 2023

A Retrospective Cohort Study: Utility of Fecal Occult Blood Test in the Acute Hospital Setting and Its Clinical Impacts