Deprivation and Rurality Mediate Income Inequality's Association with Colorectal Cancer Outcomes.

Introduction: Income inequality is associated with poor health outcomes, but its association with colorectal cancer is not well-studied. The authors aimed to determine the association between income inequality and colorectal cancer incidence/mortality in U.S.

Feasibility of a Tungsten-181 HDR brachytherapy source: Analysis of isotope production and source dosimetry.

Background: Interest in Intensity Modulated Brachytherapy (IMBT) for High Dose Rate Brachytherapy (HDR) treatments has steadily increased in recent years. However, intensity modulation is not best optimized for currently used HDR sources since they emit high energy photons. To that end, the focus on IMBT has moved to middle energy sources, such as Ytterbium-169; yet even Yb-169 emits some high energy photons at a low yield.

Predictors of recurrence and long-term patient reported outcomes following surgical repair of anal fistula, a retrospective analysis.

Purpose: Surgery for anal fistulas can result in devastating complications, including reoperations and fecal incontinence. There is limited contemporary evidence comparing outcomes since the adoption of the ligation of intersphincteric fistula tract procedure into mainstream practice. The purpose of this study is to compare recurrence rates and long-term outcomes of anal fistula following repair.

Drainage of anorectal abscesses in the operating room is associated with a decreased risk of abscess recurrence and fistula formation.

Background: Timely incision and drainage (I&D) is first line management for anorectal abscesses. We aimed to define current practices in anorectal abscess management and identify factors associated with abscess recurrence and fistula formation.

Methods: Index episodes of anorectal abscesses treated with I&D in 2014-2018 at a multi-hospital healthcare system were included.

DNA Mismatch Repair-deficient Rectal Cancer Is Frequently Associated With Lynch Syndrome and With Poor Response to Neoadjuvant Therapy.

We evaluated 368 consecutively resected rectal cancers with neoadjuvant therapy for DNA mismatch repair (MMR) protein status, tumor response to neoadjuvant therapy, histopathologic features, and patient survival. Nine (2.4%) rectal cancers were mismatch repair-deficient (MMRD): 8 (89%) Lynch syndrome-associated tumors and 1 (11%) sporadic MLH1-deficient tumor.

Developing Opioid Prescription Guidelines After Anorectal Surgery: Do Patient-Reported Outcomes and Risk Factors Influence Consumption?

Background: Opioids prescribed to address postoperative pain drive opioid-related deaths in the United States. Prescribing guidelines have been developed for many general surgical procedures, which have decreased opioid prescription and consumption. The literature on opioids after anorectal surgery is lacking.

Transanal excision with adjuvant therapy for pT1N0 rectal tumors with high-risk features offers equivalent survival to radical resection: A National Cancer Database analysis.

Background: Current guidelines favor transabdominal radical resection (RR) over transanal local excision (TAX) followed by adjuvant therapy (TAXa) for pT1N0 rectal tumors with high-risk features. Comparison of oncologic outcomes between these approaches is limited, although the former is associated with increased postoperative morbidity. We hypothesize that such treatment strategies result in equivalent long-term survival.

Intensity modulated high dose rate ocular brachytherapy using Se-75.

Purpose: We propose an alternative to LDR brachytherapy for the treatment of ocular melanomas by coupling intensity modulation, through the use of a gold shielded ring applicator, with a middle energy HDR brachytherapy source, Se-75. In this study, we computationally test this proposed design using MCNP6.

Methods And Materials: An array of discrete Se-75 sources is formed into a ring configuration within a gold shielded applicator, which collimates the beam to a conical shape.

The Role of Adjuvant Chemotherapy Following Right Hemicolectomy for Non-metastatic Mucinous and Nonmucinous Appendiceal Adenocarcinoma.

Background: Appendiceal adenocarcinoma (AA) represents a heterogenous group of neoplasms with distinct histologic features. The role and efficacy of adjuvant chemotherapy (AC) in non-metastatic disease remain controversial. The aim of this study was to ascertain the role of AC in non-metastatic AA in a national cohort of patients.

Shielded high dose rate ocular brachytherapy using Yb-169.

We propose an approach for treating ocular melanoma using a new type of brachytherapy treatment device. This device couples Yb-169, a middle-energy high dose rate (HDR) brachytherapy source, with a gold shielded ring applicator to better conform radiation exposures to the tumor. In this study, we computationally test the dosimetric output of our proposed shielded ring applicator design using MCNP6 and validate it against an I-125 COMS plaque.

Patient Factors Limit Colon Cancer Survival at Safety-Net Hospitals: A National Analysis.

Background: Safety-net hospitals serve a vital role in society by providing care for vulnerable populations. Existing data regarding oncologic outcomes of patients with colon cancer treated at safety-net hospitals are limited and variable. The objective of this study was to delineate disparities in treatment and outcomes for patients with colon cancer treated at safety-net hospitals.

Readmission After Surgical Resection for Colon and Rectal Cancers: A Retrospective Cohort Study.

Background: Colorectal adenocarcinoma is a leading cause of cancer mortality worldwide, often requiring patients to undergo anatomy-altering surgical interventions leading to increased postoperative readmission. Hospital readmission rates have been correlated with increased mortality. Therefore, it is important to understand the association between 30-day readmission rates and mortality as well as the factors associated with increased readmission rates.

Time-Dependent Displacement of Commensal Skin Microbes by Pathogens at the Site of Colorectal Surgery.

Background: Although the healthy human skin microbiome has been the subject of recent studies, it is not known whether alterations among commensal microbes contribute to surgical site infections (SSIs). Our objective in this study was to characterize temporal and spatial variation in the skin microbiota of patients undergoing colorectal surgery and determine if dysbiosis contributes to SSIs.

Methods: Sixty one adults scheduled to undergo elective colon or rectal resection were identified by convenience sampling.

Monte Carlo dosimetric characterization of a new high dose rate Yb brachytherapy source and independent verification using a multipoint plastic scintillator detector.

Purpose: A prototype Yb source was developed in combination with a dynamic rotating platinum shield system (AIM-Brachy) to deliver intensity modulated brachytherapy (IMBT). The purpose of this study was to evaluate the dosimetric characteristics of the bare/shielded Yb source using Monte Carlo (MC) simulations and perform an independent dose verification using a dosimetry platform based on a multipoint plastic scintillator detector (mPSD).

Methods: The TG-43U1 dosimetric parameters were calculated for the source model using RapidBrachyMCTPS.

Refusal of cancer-directed treatment by colon cancer patients: Risk factors and survival outcomes.

Aim: Surgery with or without chemotherapy represent the only curative option for patients with colon cancer. However, some patients refuse treatment despite the recommendation. This study aims to identify the incidence, risk factors and impact on survival associated with refusal.

Impact of Enhanced Recovery Pathways and early urinary catheter removal on post-operative urinary retention.

Background: Post-operative urinary retention (POUR) is a common complication after colorectal surgery. Enhanced recovery pathways (ERP) typically include early catheter removal but may place patients at risk for POUR.

Methods: This is a retrospective cohort analysis of patients undergoing colorectal surgery at a single institution between April 2014 and November 2017.

Intratumoral budding and automated CD8-positive T-cell density in pretreatment biopsies can predict response to neoadjuvant therapy in rectal adenocarcinoma.

Tumor budding and CD8-positive (+) T-cells are recognized as prognostic factors in colorectal adenocarcinoma. We assessed CD8+ T-cell density and intratumoral budding in pretreatment rectal cancer biopsies to determine if they are predictive biomarkers for response to neoadjuvant therapy and survival. Pretreatment biopsies of locally advanced rectal adenocarcinoma from 117 patients were evaluated for CD8+ T-cell density using automated quantitative digital image analysis and for intratumoral budding and correlated with clinicopathological variables on postneoadjuvant surgical resection specimens, response to neoadjuvant therapy, and survival.

Time to Surgery and Colon Cancer Survival in the United States.

Purpose: Time to surgery (TTS) is of concern to patients diagnosed with cancer and their physicians. Controversy surrounds the impact of TTS on colon cancer survival. There are limited national data evaluating the association; thus, our aim was to estimate the overall survival (OS) impact from increasing TTS for patients with colon cancer.

Postoperative nausea and vomiting in patients undergoing colorectal surgery within an institutional enhanced recovery after surgery protocol: comparison of two prophylactic antiemetic regimens.

Background: Enhanced recovery protocols (ERP) provide optimal perioperative care for surgical patients. Postoperative nausea and vomiting (PONV) is common after colorectal surgery (CRS). We aim to compare the efficacy of aprepitant to a cost-effective alternative, perphenazine, as components of triple antiemetic prophylaxis in ERP patients.

Fat Grafting for Improved Ileostomy Ostomy Device Fit: A Case Report.

Unlabelled: For patients with an ostomy, a poor fitting appliance may cause leakage, peristomal dermatitis, and frequent appliance changes.

Purpose: The purpose of this case study was to report the outcome of fat grafting to augment peristomal soft tissue and improve appliance fit.

Case Study: A 57-year-old woman with a history of Crohn's disease presented with soft-tissue deficiency and uneven contour around her ileostomy site.

Comparison of methods to estimate water-equivalent diameter for calculation of patient dose.

Modern CT systems seek to evaluate patient-specific dose by converting the CT dose index generated during a procedure to a size-specific dose estimate using conversion factors that are related to patient attenuation properties. The most accurate way to measure patient attenuation is to evaluate a full-field-of-view reconstruction of the whole scan length and calculating the true water-equivalent diameter (D ) using CT numbers; however, due to time constraints, less accurate methods to estimate D using patient geometry measurements are used more widely. In this study we compared the accuracy of D values calculated from three different methods across 35 sample scans and compared them to the true D .

Reassessment of Resuspension Factor Following Radionuclide Dispersal: Toward a General-purpose Rate Constant.

A recent analysis of historical radionuclide resuspension datasets confirmed the general applicability of the Anspaugh and modified Anspaugh models of resuspension factors following both controlled and disastrous releases. While observations appear to have larger variance earlier in time, previous studies equally weighted the data for statistical fit calculations; this could induce a positive skewing of resuspension coefficients in the early time-period. A refitting is performed using a relative instrumental weighting of the observations.

Changes in Occupational Radiation Exposures after Incorporation of a Real-time Dosimetry System in the Interventional Radiology Suite.

A statistical pilot study was retrospectively performed to analyze potential changes in occupational radiation exposures to Interventional Radiology (IR) staff at Lawrence General Hospital after implementation of the i2 Active Radiation Dosimetry System (Unfors RaySafe Inc, 6045 Cochran Road Cleveland, OH 44139-3302). In this study, the monthly OSL dosimetry records obtained during the eight-month period prior to i2 implementation were normalized to the number of procedures performed during each month and statistically compared to the normalized dosimetry records obtained for the 8-mo period after i2 implementation. The resulting statistics included calculation of the mean and standard deviation of the dose equivalences per procedure and included appropriate hypothesis tests to assess for statistically valid differences between the pre and post i2 study periods.

A brachytherapy photon radiation quality index Q(BT) for probe-type dosimetry.

Introduction: In photon brachytherapy (BT), experimental dosimetry is needed to verify treatment plans if planning algorithms neglect varying attenuation, absorption or scattering conditions. The detector's response is energy dependent, including the detector material to water dose ratio and the intrinsic mechanisms. The local mean photon energy E¯(r) must be known or another equivalent energy quality parameter used.