Association of Age and Overall Survival in Surgically Resected Colorectal Cancer Patients.

INTRODUCTION: Incidence of colorectal cancer (CRC) among young patients has increased in the last 20 y often with more aggressive tumor biology. It is unclear if age < 50 y is an independent factor for shorter overall survival in CRC patients. Our objective was to determine if younger age at diagnosis was associated with worse overall survival. METHODS: This study used the National Cancer Data Base (2004-2016), retrospectively reviewing patients who underwent surgical resection for CRC. Patients were limited to only those without comorbidities and primary outcome was overall survival for all patients. RESULTS: Older patients have worse overall survival as compared to younger patients at a lower stage of disease (I and II) after adjusting for tumor location, gender, histology, stage, and systemic chemotherapy (< 36 y old versus 36-55 y old hazard ratio [HR] 1.16, confidence interval [CI] 1.03-1.29). This survival benefit is eliminated at a higher stage of disease, stage III in 36-55 y old versus < 36 y old (HR 0.96 [CI 0.90-1.03.99]) and stage IV (HR 0.94 [CI 0.89-0.99]). CONCLUSIONS: Older patients (aged > 36 y) have worse overall survival at a lower stage of disease, but the survival among all age groups was similar for stage III or IV disease in CRC.

Predictors of Success When Implementing an Electromagnetic Navigational Bronchoscopy Program.

INTRODUCTION: With the advent of lung cancer screening, lung nodules are being discovered at an increasing rate. With improvements in transbronchial biopsy technology, it is important for thoracic surgeons to be involved with diagnostic procedures. The aim of this project is to relate the thoracic surgeon experience in implementing an electromagnetic navigational bronchoscopy (ENB) program at our institution and describe the factors that led to successful navigation (the ability to position a biopsy instrument in range for biopsy) and diagnostic biopsy of nodules. METHODS: The thoracic surgery ENB program was initiated in 2014. A retrospective analysis of patients referred to thoracic surgery from 2014 to 2019 for lung nodule evaluation was performed. Patients who underwent ENB and biopsy were included. Recursive partitioning (CART) and multivariable regression analyses were used to identify predictors of successful navigation and biopsy. RESULTS: There were 73 patients who underwent ENB evaluation of 91 nodules from 2014 to 2019. There was successful navigation in 75.8% of nodules, and on multivariable analysis, bronchus sign, lesion size, and pleural distance were significant predictors of successful navigation. Of the lesions that had successful navigation, 65.2% had a diagnostic biopsy. Based on CART analysis, positive bronchus sign and lesion size ≥ 1.3 cm were most predictive of obtaining a diagnostic biopsy with a probability of 0.75. CONCLUSIONS: Nodule size, distance to the pleura, and bronchus size are independent variables of successful navigation when using ENB. However, of the lesions that were successfully reached, combined lesion size >1.3 cm and a positive bronchus sign were most predictive of obtaining a diagnostic biopsy. These factors should be considered when implementing an ENB program in a thoracic surgery practice.

Development of a Risk Score to Predict Post-Discharge Rehabilitation Care After Liver Metastasectomy.

INTRODUCTION: Need for discharge to intermediate care (DCIC) can increase length of stay and be a source of stress to patients. Estimating risk of DCIC would allow earlier involvement of case managers, improve length of stay and patient satisfaction by setting realistic expectations. The aim was to use National Surgical Quality Improvement Program dataset to develop a prediction model for DCIC after undergoing liver metastasectomy. METHODS: Data were obtained from National Surgical Quality Improvement Program 2011-2018 covering liver metastasectomy. Recursive partitioning narrowed potential predictors and identified thresholds for categorization of continuous variables. Logistic regression identified a predictive model, internally validated by using 200 bootstrap samples with replacement. A risk score was derived using Framingham Study methodology by dividing all regression coefficients by the smallest model coefficient. Receiver operating characteristic analysis identified the score that maximized sensitivity/specificity, defining low/high risk. Finally, recursive partitioning identified categories low/medium/high. RESULTS: The most parsimonious model predicting DCIC area under the curve (, 0.722, 95%CI: 0.705-0.739) identified five independent predictors including age >60, procedure type, hypertension requiring medication, albumin <3.5 mg/dL and hematocrit <30%. Internal validation resulted in expected bias-corrected area under the curve of 0.717, 95% CI: 0.698-0.732. The maximum score was 17.9 and 5.8 maximized sensitivity (sn) and specificity (sp) [sn = 81%, sp = 51%) predicting DCIC. Stratified into three groups, a score ≥9.5 identified highest risk (12.8%), ≥4.3 medium (6.1%) and <4.3 lowest risk (1.5%). CONCLUSIONS: Determining risk of DCIC benefits shared decision making and patient care. This evidence may enhance discharge planning after liver metastasectomy expediting the process. Age >60 contributed the most weight to the score, but the use of additional variables in three groups allowed further discrimination between patients.

Assessing urinary phenol and paraben mixtures in pregnant women with and without gestational diabetes mellitus: A case-control study.

Prior studies have identified the associations between environmental phenol and paraben exposures and increased risk of gestational diabetes mellitus (GDM), but no study addressed these exposures as mixtures. As methods have emerged to better assess exposures to multiple chemicals, our study aimed to apply Bayesian kernel machine regression (BKMR) to evaluate the association between phenol and paraben mixtures and GDM. This study included 64 GDM cases and 237 obstetric patient controls from the University of Oklahoma Medical Center. Mid-pregnancy spot urine samples were collected to quantify concentrations of bisphenol A (BPA), benzophenone-3, triclosan, 2,4-dichlorophenol, 2,5-dichlorophenol, butylparaben, methylparaben, and propylparaben. Multivariable logistic regression was used to evaluate the associations between individual chemical biomarkers and GDM while controlling for confounding. We used probit implementation of BKMR with hierarchical variable selection to estimate the mean difference in GDM probability for each component of the phenol and paraben mixtures while controlling for the correlation among the chemical biomarkers. When analyzing individual chemicals using logistic regression, benzophenone-3 was positively associated with GDM [adjusted odds ratio (aOR) per interquartile range (IQR) = 1.54, 95% confidence interval (CI) 1.15, 2.08], while BPA was negatively associated with GDM (aOR 0.61, 95% CI 0.37, 0.99). In probit-BKMR analysis, an increase in z-score transformed log urinary concentrations of benzophenone-3 from the 10th to 90th percentile was associated with an increase in the estimated difference in the probability of GDM (0.67, 95% Credible Interval 0.04, 1.30), holding other chemicals fixed at their medians. No associations were identified between other chemical biomarkers and GDM in the BKMR analyses. We observed that the association of BPA and GDM was attenuated when accounting for correlated phenols and parabens, suggesting the importance of addressing chemical mixtures in perinatal environmental exposure studies. Additional prospective investigations will increase the understanding of the relationship between benzophenone-3 exposure and GDM development.

Misclassification Error-Adjusted Prevalence of Injection Drug Use Among Infective Endocarditis Hospitalizations in the United States: A Serial Cross-Sectional Analysis of the 2007-2016 National Inpatient Sample.

Administrative health databases have been used to monitor trends in infective endocarditis hospitalization related to nonprescription injection drug use (IDU) using International Classification of Diseases (ICD) code algorithms. Because no ICD code for IDU exists, drug dependence and hepatitis C virus (HCV) have been used as surrogate measures for IDU, making misclassification error (ME) a threat to the accuracy of existing estimates. In a serial cross-sectional analysis, we compared the unadjusted and ME-adjusted prevalences of IDU among 70,899 unweighted endocarditis hospitalizations in the 2007-2016 National Inpatient Sample. The unadjusted prevalence of IDU was estimated with a drug algorithm, an HCV algorithm, and a combination algorithm (drug and HCV). Bayesian latent class models were used to estimate the median IDU prevalence and 95% Bayesian credible intervals and ICD algorithm sensitivity and specificity. Sex- and age group-stratified IDU prevalences were also estimated. Compared with the misclassification-adjusted prevalence, unadjusted estimates were lower using the drug algorithm and higher using the combination algorithm. The median ME-adjusted IDU prevalence increased from 9.7% (95% Bayesian credible interval (BCI): 6.3, 14.8) in 2008 to 32.5% (95% BCI: 26.5, 38.2) in 2016. Among persons aged 18-34 years, IDU prevalence was higher in females than in males. ME adjustment in ICD-based studies of injection-related endocarditis is recommended.

Association of Interfacility Helicopter versus Ground Ambulance Transport and in-Hospital Mortality among Trauma Patients.

BACKGROUND: Relatively few studies have compared outcomes between helicopter transport (HT) and ground transport (GT) for the inter-facility transfer of trauma patients to tertiary trauma centers (TTC). Mixed results have been reported from these studies ranging from a slight increase in odds of survival for the severely injured to no evident benefit for HT patients. We hypothesized there was no adjusted difference in mortality between patients transported interfacility by HT or GT taking into account distance from TTC. METHODS: Data from an inclusive statewide trauma registry was used to conduct a retrospective cohort study of adult (18+ years old) trauma patients who initially presented to a non-tertiary trauma center (NTC) before subsequent transfer by HT or GT to a TTC. Records from the NTC and TTC were linked (N = 9880). We used propensity adjusted, multivariable Cox proportional hazards models to assess the association of HT on mortality at 72-hour and within the first 2 weeks of arrival at a TTC; these multivariable analyses were stratified by distance (miles) between NTC and TTC: 21-90, and greater than 90. RESULTS: Mean distance between NTC and TTC was greater for HT patients, 96.7 miles versus 69.9 miles for GT. A higher proportion of patients among the HT group had an ISS of 16 or higher (24.6% vs 10.9%), an initial SBP < 90 mmHg (7.3% vs 2.8%), and GCS < 10 (12.5% vs 3.7%) than the GT group. HT was associated with significantly decreased 72-hour mortality (HR 0.65, 95%CI 0.48-0.90) for patients transferred from a NTC <90 miles from the TTC. No association was seen for patients transferred more than 90 miles to the TTC. No significant association of HT and 2-week mortality was seen at any distance from the TTC. CONCLUSIONS: Only for patients transferred from an NTC <90 miles from the receiving TTC was HT associated with a significantly decreased hazard of mortality in the first 72 hours. Many HT patients, especially from the most distant NTCs, had minor injuries and normal vital signs at both the NTC and TTC suggesting the decision to use HT for these patients was resource-driven rather than clinical.

Obesity is an Independent Risk Factor for Mortality in Otherwise Healthy Patients After Hepatectomy.

BACKGROUND: Obesity is often associated with comorbidities that limit remnant liver recovery after hepatectomy. The extent to which obesity, in the absence of comorbidities, impacts surgical risk after hepatectomy is unknown. We hypothesized that an obese population without major comorbidities would not be at increased risk of adverse outcomes after hepatectomies. METHODS: We performed a retrospective analysis identifying patients who underwent hepatectomies from the American College of Surgeons National Surgical Quality Improvement Program data set 2005-2017. Outcomes of interest included the following: mortality, any morbidity, critical care complications, and failure to discharge home. Body mass index (BMI) was the primary variable of interest, grouped as ≥35 and <35 based on bivariate tests of associations with candidate cut-off points. In attempt to isolate the effect of obesity on outcomes among patients "without major comorbidities" (WOC), we included patients without diabetes, chronic obstructive pulmonary disease, renal insufficiency, and nonsmokers; remaining patients were grouped as "with major comorbidities" (WC). Multivariable logistic regression was used to test whether obesity is independently associated with the outcomes of interest after adjustment for other covariates. RESULTS: A total of 36,396 patients were included. There were 13,754 patients in the WOC group and 22,642 in the WC group. Among patients in the WOC group, the adjusted odds of mortality were 2.2 times higher for patients with a BMI ≥35 versus a BMI <35. Among the patients in the WC group, a BMI ≥35 was not a statistically significant predictor of mortality after adjustment for other covariates. Obese patients had increased odds of each outcome among the WOC group. CONCLUSIONS: Our hypothesis was refuted by these data. In fact, the adverse effect of obesity was more evident among healthy patients.

Survival Benefit of Treatment at or Transfer to a Tertiary Trauma Center among Injured Older Adults.

Objective: It is well established that seriously injured older adults are under-triaged to tertiary trauma centers. However, the survival benefit of tertiary trauma centers (TC) compared to a non-tertiary trauma centers (Non-TCs) remains unclear for this patient population. Using improved methodology and a larger sample, we hypothesized that there was a difference in hospital mortality between injured older adults treated at TCs and those treated at Non-TCs. Methods: This was a retrospective cohort study of injured older adults (> =55 years) reported to the Oklahoma statewide trauma registry between 2005 and 2014. The outcome of interest was 30-day in-hospital mortality and the exposure variable of interest was level of definitive trauma care (TC vs Non-TC). Overall survival benefit of treatment at a TC as well as the survival benefit of transferring injured older adults to a TC were evaluated using multivariable survival analyses as well as propensity score-adjusted analyses. Results: Of the 25,288 patients eligible for analysis, 43% (10,927) were treated at TCs. Multivariable Cox regression analyses revealed effect modification by age group and time. After adjusting for potential confounders within the age strata, overall, patients treated at TCs were significantly less likely to die within 7 days of admission and this effect was stronger for patients aged 55-64 years (HR 0.41, 95% CI 0.31-0.52) compared to those > =65 years (HR 0.62, 95% CI 0.55-0.70). Overall survival benefit of TCs beyond 7 days was also observed (HR 0.68, 95% CI 0.56-0.83). Similarly, for the survival benefit of transferring injured older adults, after adjusting for the propensity to be transferred and other confounders, transfer to a TC was associated with lower 30-day mortality both for patients less than 65 years old (HR 0.36, 95% CI: 0.27-0.49) and those 65 years and older (HR 0.55, 95% CI: 0.48-0.64). Conclusions: Our results suggest a survival benefit for injured older adults treated at TCs. This benefit was also observed for patients transferred from non-tertiary trauma centers. Further research should focus on identifying specific subgroups of patients who would especially benefit from this level of care to minimize trauma triage inefficiencies.

Out-of-hospital and Inter-hospital Under-triage to Designated Tertiary Trauma Centers among Injured Older Adults: A 10-year Statewide Geospatial-Adjusted Analysis.

OBJECTIVE: While out-of-hospital under-triage of seriously injured older adults to tertiary trauma centers has long been acknowledged, no study has adjusted for place of injury or evaluated the extent of inter-facility under-triage. We sought to determine distance and confounder adjusted odds of treatment at a tertiary trauma center (TTC) for older adult trauma patients compared to younger trauma patients, for patients transported from the scene of injury and those transferred from a non-tertiary trauma (NTTC) center. METHODS: This was a retrospective cohort study utilizing data from a statewide trauma registry reported over a 10-year period (2005-14). The outcome of interest was treatment at an American College of Surgeons or state-designated Level I/II trauma center (TTC). The predictor variable of interest was age group (> = 55 years vs. < 55 years). Covariates of interest included patient demographics, clinical characteristics and various distance measures calculated based on the patient's injury location. RESULTS: 84 930 patients met study criteria. Of these 42% (35659) were 55 years and older with an average age of 74 years (SD, 11.6). Older adult patients were on average, injured slightly farther away from a TTC (median distance, 34 vs. 29 miles, p < 0.001). Among patients initially presenting to NTTCs, older adults were significantly more likely to be transferred to another NTTC (53% vs. 34%). After adjusting for confounders and distance measures, older adults were less likely to be treated at TTCs overall (OR = 0.54, 95% CI: 0.52-0.56), whether transported by EMS from the scene of injury (OR = 0.47, 95% CI: 0.44-0.50) or via inter-facility transfer (OR = 0.63, 95%CI: 0.59-0.68). CONCLUSIONS: Injured older adults face significant under-triage to TTCs whether by EMS from the scene of injury or via transfer from NTTCs. Adjusting for proximity of injury to a TTC does not alter these findings.

Factors Associated with the Use of Helicopter Inter-facility Transport of Trauma Patients to Tertiary Trauma Centers within an Organized Rural Trauma System.

OBJECTIVE: A review of the literature yielded little information regarding factors associated with the decision to use ground (GEMS) or helicopter (HEMS) emergency medical services for trauma patients transferred inter-facility. Furthermore, studies evaluating the impact of inter-facility transport mode on mortality have reported mixed findings. Since HEMS transport is generally reserved for more severely injured patients, this introduces indication bias, which may explain the mixed findings. Our objective was to identify factors at referring non-tertiary trauma centers (NTC) influencing transport mode decision. METHODS: This was a case-control study of trauma patients transferred from a Level III or IV NTC to a tertiary trauma center (TTC) within 24-hours reported to the Oklahoma State Trauma Registry between 2005 and 2012. Multivariable logistic regression was used to determine clinical and non-clinical factors associated with the decision to use HEMS. RESULTS: A total of 7380 patients met the study eligibility. Of these, 2803(38%) were transported inter-facility by HEMS. Penetrating injury, prehospital EMS transport, severe torso injury, hypovolemic shock, and TBI were significant predictors (p<0.05) of HEMS use regardless of distance to a TTC. Association between HEMS use and male gender, Level IV NTC, and local ground EMS resources varied by distance from the TTC. Many HEMS transported patients had minor injuries and normal vital signs. CONCLUSIONS: Our results suggest that while distance remains the most influential factor associated with HEMS use, significant differences exist in clinical and non-clinical factors between patients transported by HEMS versus GEMS. To ensure comparability of study groups, studies evaluating outcome differences between HEMS and GEMS should take factors determining transport mode into account. The findings will be used to develop propensity scores to balance baseline risk between GEMS and HEMS patients for use in subsequent studies of outcomes.

Traumatic liver injuries in the elderly as compared to younger adults.

BACKGROUND: Comparing elderly (> 55 years) and younger (< 55 and > 15 years) traumatic liver injury patients, we evaluated differences in the need for operative intervention as well as transfusion requirements in those treated non-operatively. METHODS: This was a retrospective cohort study of adult patients with liver trauma. The analyses evaluated overall adjusted differences in treatment option and packed red blood utilization in those treated non-operatively by age group. RESULTS: 841 patients were included. 83 were elderly. Operative management occurred in 13% and 12% of the younger adults and elderly patients, respectively. After adjustment, age group was not significantly associated with treatment option. In the non-operative setting, elderly patients had twice the red blood cell transfusion requirement as compared to younger adults. CONCLUSIONS: Age does not play a role in considering the need for surgical intervention in patients with liver trauma. However, the geriatric population has twice the transfusion requirement in the non-operative setting.

Learning Curve of a Laparoscopic Pancreaticoduodenectomy Program at a Second Institution.

BACKGROUND: Historically, pancreaticoduodenectomy (PD) has been performed via a laparotomy, but increasingly, laparoscopic and robotic platforms are being employed for PD. Laparoscopic PD has a steep surgeon specific learning curve and programmatic elements that must be optimized. These factors may limit a surgeon who is proficient at laparoscopic PD to develop a program at another institution. We hypothesize that the learning curve for a surgeon transferring a program to a second institution is shorter than the initial laparoscopic PD learning curve for the same surgeon. METHODS: A retrospective review of patients who underwent laparoscopic PD for any indication at the first institution (FI) from 2012 to 2017 and the second institution (SI) from 2018 to 2021 was conducted. Standard statistical analysis was performed. The learning curve was identified using one-sided CUSUM analysis of operative times. RESULT: We identified 110 participants, 90 from the FI and 20 from the SI. More patients at the FI were diagnosed with periampullary adenocarcinoma on final pathology compared to the SI (65.6% vs 40.0%, P = .0132). FI operative times stabilized after the 25th laparoscopic PD and SI operative times stabilized after the 5th operation. No statistically significant difference was identified in postoperative complications. CONCLUSIONS: The learning curve and average operative time of an SI laparoscopic PD program was shorter than the initial learning curve for a single surgeon with comparable outcomes. This suggests that complex minimally invasive surgical programs can be safely transferred to another high-volume institution without significant loss of progress.

Variations in procedure time based on surgery resident postgraduate year level.

BACKGROUND: With increasing scrutiny being placed on the allocation of health care dollars, data supporting the increased resources used to teach residents in the operating room (OR) are lacking. METHODS: All cases of patients undergoing laparoscopic cholecystectomies (LCs) and pancreaticoduodenectomies (PDs) from July 1, 2006 to July 1, 2011 were analyzed. Procedures were excluded based on the following: more than one resident listed in the operative report, with the exception of interns; LC requiring cholangiogram or conversion to an open procedure; or if a PD required additional procedures. Multiple linear regression was used to evaluate the association between procedure time and postgraduate year (PGY), adjusting for patient age and estimated blood loss. RESULTS: A total of 236 PDs and 357 LCs were included in the study. For LCs, after multiple linear regression, the association between procedure time and resident PGY was marginally significant (P = 0.0519) and suggested an inverse relationship; for every increase in resident PGY, there was a 2.66-min decrease in OR time. Based on our institution's figure of $18.13/min of OR time, the cost difference between PGYs 1 and 5 performing a LC would be $192.90 per case. For PDs, however, the association between procedure time and resident PGY was not significant. CONCLUSIONS: Junior residents likely prolong procedure times for more basic procedures such as LC but not for more complex procedures such as PD.

Establishing a swine model to compare vascular prostheses in a contaminated field.

OBJECTIVE: Patch arteriotomies are performed during many vascular procedures. Whereas synthetic materials are generally felt to be inappropriate for infected environments, the suitability of glutaraldehyde-treated bovine pericardium (GBP), a biologic material, in such instances is unknown. Our main objectives were to develop an animal model to study vascular prostheses while comparing the infectability of polyester (Dacron) and GBP in a topically infected environment. METHODS: Twenty-three pigs underwent transabdominal patch arteriotomy of the infrarenal aorta with either Dacron or GBP. The patches were inoculated with sterile saline (1 per group), Staphylococcus aureus 10(4) colony-forming units (CFUs) (4 per group), or S. aureus 10(5) CFUs (6 per group). At 3 wk, the animals were euthanized, and the patches were removed via a left retroperitoneal approach. Specimens were collected for microbiologic and histologic analysis. RESULTS: One animal from each group inoculated with 10(5) CFUs died during the study period, and another died immediately postoperatively of an airway complication. All aortas were patent and without evidence of pseudoaneurysm formation. Gross abscesses were found in 4/6 Dacron and 5/6 GBP animals receiving 10(5) CFUs. Similarly, 4/6 animals implanted with Dacron and 5/6 animals implanted with GBP had positive tissue cultures. A histologic grading system of inflammation substantiated the culture results. CONCLUSIONS: No significant difference exists between Dacron and GBP to resist bacterial infection at 3 wk. We have established a reproducible in vivo model to study arterial patch materials in a topically infected environment.

Enhancing utility of interfacility triage guidelines using machine learning: Development of the Geriatric Interfacility Trauma Triage score.

BACKGROUND: Undertriage of injured older adults to tertiary trauma centers (TTCs) has been demonstrated by many studies. In predominantly rural regions, a majority of trauma patients are initially transported to nontertiary trauma centers (NTCs). Current interfacility triage guidelines do not highlight the hierarchical importance of risk factors nor do they allow for individual risk prediction. We sought to develop a transfer risk score that may simplify secondary triage of injured older adults to TTCs. METHODS: This was a retrospective prognostic study of injured adults 55 years or older initially transported to an NTC from the scene of injury. The study used data reported to the Oklahoma State Trauma Registry between 2009 and 2019. The outcome of interest was either mortality or serious injury (Injury Severity Score, ≥16) requiring an interventional procedure at the receiving facility. In developing the model, machine-learning techniques including random forests were used to reduce the number of candidate variables recorded at the initial facility. RESULTS: Of the 5,913 injured older adults initially transported to an NTC before subsequent transfer to a TTC, 32.7% (1,696) had the outcome of interest at the TTC. The final prognostic model (area under the curve, 75.4%; 95% confidence interval, 74-76%) included the following top four predictors and weighted scores: airway intervention (10), traffic-related femur fracture (6), spinal cord injury (5), emergency department Glasgow Coma Scale score of ≤13 (5), and hemodynamic support (4). Bias-corrected and sample validation areas under the curve were 74% and 72%, respectively. A risk score of 7 yields a sensitivity of 78% and specificity of 56%. CONCLUSION: Secondary triage of injured older adults to TTCs could be enhanced by use of a risk score. Our study is the first to develop a risk stratification tool for injured older adults requiring transfer to a higher level of care. LEVEL OF EVIDENCE: Prognostic and Epidemiolgical; Level III.

The Effect of Body Mass Index on the Creation of an End-Colostomy in Rectal Cancer Patients.

With the increasing prevalence of obesity, there has been a parallel increase in the incidence of rectal cancer. The association of body mass index (BMI) and end-colostomy creation versus primary anastomosis in patients undergoing proctectomy for rectal cancer has not been described. This is a retrospective study of patients with rectal cancer from 2012 to 2018 using data from the National Surgical Quality Improvement Project. 16,446 (92.1%) underwent primary anastomosis and 1,418 (7.9%) underwent creation of an end-colostomy. Patients with a BMI of 25-29.9 (overweight) comprised the most frequent group to have a proctectomy (reference group), but the least likely to have an end-colostomy. Patients with severe obesity (BMI 50+) had an adjusted odds ratio for end-colostomy of 2.7 (95% CI 1.5-4.7) compared to the reference group. Patients who have severe obesity should be counseled regarding the likelihood of an end-colostomy and may benefit from medical weight management or weight-loss surgery.

Dynamic 2-deoxy-D-glucose-enhanced multispectral optoacoustic tomography for assessing metabolism and vascular hemodynamics of breast cancer.

Clinical tools for measuring tumor vascular hemodynamics, such as dynamic contrast-enhanced MRI, are clinically important to assess tumor properties. Here we explored the use of multispectral optoacoustic tomography (MSOT), which has a high spatial and temporal resolution, to measure the intratumoral pharmacokinetics of a near-infrared-dye-labeled 2-Deoxyglucose, 2-DG-800, in orthotropic 2-LMP breast tumors in mice. As uptake of 2-DG-800 is dependent on both vascular properties, and glucose transporter activity - a widely-used surrogate for metabolism, we evaluate hemodynamics of 2-DG-MP by fitting the dynamic MSOT signal of 2-DG-800 into two-compartment models including the extended Tofts model (ETM) and reference region model (RRM). We showed that dynamic 2-DG-enhanced MSOT (DGE-MSOT) is powerful in acquiring hemodynamic rate constants, including Ktrans and Kep, via systemically injecting a low dose of 2-DG-800 (0.5 µmol/kg b.w.). In our study, both ETM and RRM are efficient in deriving hemodynamic parameters in the tumor. Area-under-curve (AUC) values (which correlate to metabolism), and Ktrans and Kep values, can effectively distinguish tumor from muscle. Hemodynamic parameters also demonstrated correlations to hemoglobin, oxyhemoglobin, and blood oxygen level (SO2) measurements by spectral unmixing of the MSOT data. Together, our study for the first time demonstrated the capability of DGE-MSOT in assessing vascular hemodynamics of tumors.

Simultaneous Detection of Multiple Tumor-targeted Gold Nanoparticles in HER2-Positive Breast Tumors Using Optoacoustic Imaging.

Purpose To develop optoacoustic, spectrally distinct, actively targeted gold nanoparticle-based near-infrared probes (trastuzumab [TRA], TRA-Aurelia-1, and TRA-Aurelia-2) that can be individually identifiable at multispectral optoacoustic tomography (MSOT) of human epidermal growth factor receptor 2 (HER2)-positive breast tumors. Materials and Methods Gold nanoparticle-based near-infrared probes (Aurelia-1 and 2) that are optoacoustically active and spectrally distinct for simultaneous MSOT imaging were synthesized and conjugated to TRA to produce TRA-Aurelia-1 and 2. Freshly resected human HER2-positive (n = 6) and HER2-negative (n = 6) triple-negative breast cancer tumors were treated with TRA-Aurelia-1 and TRA-Aurelia-2 for 2 hours and imaged with MSOT. HER2-expressing DY36T2Q cells and HER2-negative MDA-MB-231 cells were implanted orthotopically into mice (n = 5). MSOT imaging was performed 6 hours following the injection, and the Friedman test was used for analysis. Results TRA-Aurelia-1 (absorption peak, 780 nm) and TRA-Aurelia-2 (absorption peak, 720 nm) were spectrally distinct. HER2-positive human breast tumors exhibited a significant increase in optoacoustic signal following TRA-Aurelia-1 (28.8-fold) or 2 (29.5-fold) (P = .002) treatment relative to HER2-negative tumors. Treatment with TRA-Aurelia-1 and 2 increased optoacoustic signals in DY36T2Q tumors relative to those in MDA-MB-231 controls (14.8-fold, P < .001; 20.8-fold, P < .001, respectively). Conclusion The study demonstrates that TRA-Aurelia 1 and 2 nanoparticles operate as a spectrally distinct HER2 breast tumor-targeted in vivo optoacoustic agent. Keywords: Molecular Imaging, Nanoparticles, Photoacoustic Imaging, Breast Cancer Supplemental material is available for this article. © RSNA, 2023.

Risk Factors Associated With Readmission After Pancreatectomy: A Single-Institution Retrospective Cohort Study.

BACKGROUND: Pancreatectomy has a significant rate of procedure-specific morbidity which can result in readmission. Readmission has been proposed as a measure of quality. The goal of this study is to determine what factors are associated with readmission after pancreatectomy and whether readmission can be prevented. METHODS: A retrospective review of a single institution's pancreatectomies between January 2011 and April 2015 was performed. Demographic, perioperative, and outpatient data were collected from the medical record. Primary outcome was 90-day readmission. Univariate and multivariable analyses were performed to determine which factors were associated with increased risk for readmission. RESULTS: A total of 257 patients met inclusion criteria; the 90-day readmission rate was 32.7%. The median time to readmission was 13 days. Readmitted patients were more likely to have a postoperative pancreatic fistula (POPF) on univariate analysis. Surgical site infections were more common in readmitted patients (18% vs 6.4%, P = .0138). Upon multivariable adjustment, only POPF (P = .0005) remained significant. A positive dose-response relationship was noted between POPF grade and the odds of readmission with odds ratios (ORs) ranging from 1.6 (95% Confidence Interval (CI): .6-4.1) for grade A to 16.7 (95% CI: 1.8-156.8) for grade C, albeit with limited precision. CONCLUSIONS: Readmission after pancreatectomy is a common occurrence despite the many advancements in perioperative care. Our data suggest that POPF is a risk factor for readmission after pancreatectomy. Presently, this factor is not clearly preventable. This suggests that readmission may not be the best measure of quality to utilize in the evaluation of pancreatic surgery.

Retrospective Cohort Analysis of the Effect of Age on Lymph Node Harvest, Positivity, and Ratio in Colorectal Cancer.

Introduction: Colon cancer among young patients has increased in incidence and mortality over the past decade. Our objective was to determine if age-related differences exist for total positive nodes (TPN), total lymph node harvest (TLH), and lymph node ratio (LNR). Material and Methods: A retrospective review of stage III surgically resected colorectal cancer patient data in the National Cancer Database (2004−2016) was performed, reviewing TPN, TLH, and LNR (TPN/TLH). Results: Unadjusted analyses suggested significantly higher levels of TLH and TPN (p < 0.0001) in younger patients, while LNR did not differ by age group. On adjusted analysis, TLH remained higher in younger patients (<35 years 1.56 (CI 95 1.54, 1.59)). The age-related effect was less pronounced for LNR (<35 years 1.16 (CI 95 1.13, 1.2)). Conclusion: Younger patients have increased TLH, even after adjusting for known confounders, while age does not have a strong independent impact on LNR.