NCCN Guidelines® Insights: Colorectal Cancer Screening, Version 1.2024.

The NCCN Guidelines for Colorectal Cancer (CRC) Screening describe various colorectal screening modalities as well as recommended screening schedules for patients at average or increased risk of developing sporadic CRC. They are intended to aid physicians with clinical decision-making regarding CRC screening for patients without defined genetic syndromes. These NCCN Guidelines Insights focus on select recent updates to the NCCN Guidelines, including a section on primary and secondary CRC prevention, and provide context for the panel's recommendations regarding the age at which to initiate screening in average-risk individuals and those with increased risk based on personal history of childhood, adolescent, and young adult cancer.

Characteristics of gastrointestinal bleeding after placement of continuous-flow left ventricular assist device: a case series.

BACKGROUND: Medical management of patients with continuous-flow left ventricular assist devices (LVADs) remains challenging for the gastroenterologist given their high risk of gastrointestinal bleeding (GIB) and need for continuous anticoagulation. AIMS: Our aim was to better characterize LVAD patients who presented with a GIB at our facility and delineate the prevalence, presentation, time to diagnosis, management, and therapeutic endoscopic interventions, including small bowel tools that may offer additional benefit. METHODS: We retrospectively reviewed adult patients (>18 years) who underwent LVAD implantation at our tertiary care facility between October 2011 and October 2013. Electronic medical records were reviewed for presenting symptoms, average days to initial and repeat GIB, hospital course, and techniques that led to diagnosis and hemostasis. RESULTS: Eighteen patients underwent LVAD implantation, of which 61 % presented with a GIB for a total of 20 presentations (1.8 per patient). Mean time to initial GIB was 154 days. Patients required an average of 1.8 endoscopic procedures per admission. Esophagogastroduodenoscopy (EGD) and push enteroscopy (PE) were more likely to lead to a diagnosis, and EGD was the most commonly used diagnostic tool at initial presentation. Sixty percent of patients who initially received EGD presented with a recurrent GIB and required PE, which was diagnostic and therapeutic for small bowel angiodysplasias in 80 % of cases. CONCLUSION: We found a higher GIB rate compared with prior studies. Bleeding events were associated with multiple procedures and interventions. We recommend an algorithmic approach to LVAD patients who bleed. Our experience suggests that PE is warranted at initial presentation in order to achieve hemostasis, prevent recurrent GIB, and decrease subsequent readmission rates.

Leukocytoclastic Vasculitis Associated with Adalimumab Therapy for Crohn's Disease.

Leukocytoclastic vasculitis (LCV) is rarely associated with anti-tumor necrosis factor [TNF] α therapy. We report a 22-year-old man with new onset of a pustular rash on his bilateral upper and lower extremities while on adalimumab therapy for Crohn's disease. Skin biopsy of the affected area showed perivascular extravasation of erythrocytes, neutrophils, eosinophils and vascular damage surrounding blood vessels associated with fibrin, consistent with LCV. Patient was treated with topical steroids and subsequently transitioned to ustekinumab therapy with follow-up colonoscopy showing minimal active disease. Our report highlights the association of a unique dermatologic autoimmune manifestation with TNF-targeted therapy in a patient with Crohn's disease.

The Risk of Colorectal Polyps after Weight Loss Therapy Versus Obesity: A Propensity-Matched Nationwide Cohort Study.

BACKGROUND: A fundamental understanding of the impact of bariatric surgery (BRS) on mechanisms of colorectal carcinogenesis is limited. For instance, studies report a reduced risk of colorectal cancer in females but not in males after BRS. We examined whether this sex-specific difference existed at the earlier polyp development stage. METHODS: This retrospective cohort study included 281,417 adults from the 2012-2020 MarketScan database. We compared polyps rates on colonoscopy in four groups: post- vs. pre-BRS (treatment) to post- vs. pre-severe obesity (SO) diagnosis (control). We focused our main analysis on a propensity-matched sample that yielded a balanced distribution of covariates in our four groups (n = 9680 adults, 21.9% males). We also adjusted for important covariates. RESULTS: Metabolic syndrome parameters improved after bariatric surgery and worsened after severe obesity diagnosis (p < 0.05). The rate of polyps was 46.7% at a median of 0.5 years pre-BRS and 47.9% at a median of 0.6 years pre-SO diagnosis. The polyps rate was 45.4% at a median (range) of 3.2 (1.0-8.5) years post-BRS. Conversely, 53.8% of adults had polyps at 3.0 (1.0-8.6) years post-SO. There was no change in the risk of colorectal polyps in males or females post- vs. pre-BRS. However, the risk of polyps was higher in males (OR = 1.32, 95% CI: 1.02-1.70) and females (OR = 1.29, 95% CI: 1.13-1.47) post- vs. pre-SO. When compared to the control group (SO), the odds ratios for colorectal polyps were lower for males and females after bariatric surgery (OR = 0.63, 95% CI: 0.44-0.90, and OR = 0.79, 95% CI: 0.66-0.96, respectively). CONCLUSIONS: Obesity is associated with an increased risk of colorectal polyps, an effect that is ameliorated after bariatric surgery. These data are relevant for studies investigating colorectal carcinogenesis mechanisms.

Hypercharge flux, exotics, and anomaly cancellation in F-theory grand unification.

We sharpen constraints related to hypercharge flux in F-theory grand unified theories that possess U(1) symmetries and argue that they arise as a consequence of four-dimensional anomaly cancellation. This gives a physical explanation for all restrictions that were observed in spectral cover models while demonstrating that the phenomenological implications for a well-motivated set of models are not tied to any particular formalism.

Guinea pig sensitization assays: an experimental comparison of three methods.

PURPOSE: Guinea pig sensitization assays provide a critical tool in toxicological testing. Here, we investigate the relative sensitivities of the Guinea Pig Maximization Test (GPMT), the Open Epicutaneous Test (OET), and the Buehler test on seven common compounds. METHODS: Seven compounds (formalin, nickel sulfate, 2-benzothiazolethiol, neomycin sulfate, potassium dichromate, ethylenediamine, dihydrochloride, and cinnamyl alcohol) were investigated on 15 guinea pigs per assay. Differences between each assay were investigated individually for each compound in question, and cumulative comparisons were also performed. RESULTS: Cumulatively, differences in rates of sensitization between the GPMT and OET did not reach statistical significance; however, both tests produced higher sensitization rates than the Buehler test (1% significance level). Comparisons for individual compounds are outlined within the main text. CONCLUSIONS: Our results indicate a possible role for the OET in the testing of weakly allergenic compounds. Similarly, the Buehler test may hold greatest utility in the examination of strongly allergenic compounds, where high sensitivity is not necessary and limited exposure to subjects is desired. These findings may help guide experimental protocols and considerations.

Comparison of colon adenoma detection rates using cap-assisted and Endocuff-assisted colonoscopy: a randomized controlled trial.

Objectives and study aim Colonoscopy prevents colorectal cancer by removing adenomatous polyps, but missed adenomas lead to interval cancers. Different devices have been used to increase adenoma detection rates (ADR). Two such devices of interest are the transparent cap (Olympus) and Endocuff (ARC Medical). Our study aimed to compare differences in ADR between Endocuff-assisted colonoscopy (EAC), cap-assisted colonoscopy (CAC) and standard colonoscopy (SC). Patients and methods A sample size of 126 subjects was calculated to determine an effect size of 30 %. Patients undergoing screening or surveillance colonoscopy between March 2016 and January 2017 were randomized to SC, CAC or EAC groups. Three experienced endoscopists performed all colonoscopies. Patient demographics, procedure indication, Boston Bowel Prep Score (BBPS), withdrawal time, polyp size, location, histopathology, were analyzed. Results There was no difference in ADR (52 %, 40 % and 54 %) in the SC, CAC and EAC groups respectively ( P  = 0.4). Similar findings were also observed for proximal ADR (45 %, 35 %, and 50 %, P  = 0.4) and SSA detection rate (16 %, 14 %, and 23 %, P  = 0.5). EAC detected higher mean ADR per colonoscopy compared to CAC (1.70 vs 0.76, P  = 0.01). However, there was no significant difference in mean ADR per positive colonoscopy (2.08, 1.63, and 2.59, P  = 0.21). Conclusion In a randomized controlled trial comparing AC to CAC and SC, neither device conferred additional benefits in ADR among high detectors. When comparing each device, EAC may be better than CAC at detecting more total adenomas.

Novel use of endoscopically placed fiducial markers for targeted radiation therapy of colonic lymphomas.

Non-Hodgkin's lymphomas (NHL) are an important variety of gastrointestinal tumors with increasing incidence and prevalence. Traditional management of NHL with chemotherapy is challenging and expanding evidence points to significant tumor response to radiation therapy (RT). However, there exists a wide range of radiation-related toxicities. Optimization of exact tumor marking coupled with minimization of the radius of radiation delivery is essential to increase patient's tolerance and decrease side effects of the treatment. We report our experience with mantle cell lymphoma of the colon treated with precision RT after endoscopic placement of resolution clips in a "shooting target" fashion in a patient who failed conventional chemotherapy. Fourteen months after completion of RT, the patient remains in complete remission.

Improved dosimetric and clinical outcomes with intensity-modulated radiotherapy for head-and-neck cancer of unknown primary origin.

PURPOSE: To compare differences in dosimetric, clinical, and quality-of-life endpoints among a cohort of patients treated by intensity-modulated radiotherapy (IMRT) and conventional radiotherapy (CRT) for head-and-neck cancer of unknown primary origin. METHODS AND MATERIALS: The medical records of 51 patients treated by radiation therapy for squamous cell carcinoma of the head and neck presenting as cervical lymph node metastasis of occult primary origin were reviewed. Twenty-four patients (47%) were treated using CRT, and 27 (53%) were treated using IMRT. The proportions of patients receiving concurrent chemotherapy were 54% and 63%, respectively. RESULTS: The 2-year estimates of overall survival, local-regional control, and disease-specific survival for the entire patient population were 86%, 89%, and 84%, respectively. There were no significant differences in any of these endpoints with respect to radiation therapy technique (p>0.05 for all). Dosimetric analysis revealed that the use of IMRT resulted in significant improvements with respect to mean dose and V30 to the contralateral (spared) parotid gland. In addition, mean doses to the ipsilateral inner and middle ear structures were significantly reduced with IMRT (p<0.05 for all). The incidence of severe xerostomia in the late setting was 58% and 11% among patients treated by CRT and IMRT, respectively (p<0.001). The percentages of patients who were G-tube dependent at 6 months after treatment were 42% and 11%, respectively (p<0.001). CONCLUSIONS: IMRT results in significant improvements in the therapeutic ratio among patients treated by radiation therapy for head-and-neck cancer of unknown primary origin.