Effectiveness of Colonoscopy Screening vs Sigmoidoscopy Screening in Colorectal Cancer.

Importance: Randomized clinical screening trials have shown that sigmoidoscopy screening reduces colorectal cancer (CRC) incidence and mortality. Colonoscopy has largely replaced sigmoidoscopy for CRC screening, but long-term results from randomized trials on colonoscopy screening are still lacking. Objective: To estimate the additional screening benefit of colonoscopy compared with sigmoidoscopy. Design, Setting, and Participants: This comparative effectiveness simulation study pooled data on 358 204 men and women randomly assigned to sigmoidoscopy screening or usual care in 4 randomized sigmoidoscopy screening trials conducted in Norway, Italy, the US, and UK with inclusion periods in the years 1993 to 2001. The primary analysis of the study was conducted from January 19 to December 30, 2021. Intervention: Invitation to endoscopic screening. Main Outcomes and Measures: Primary outcomes were CRC incidence and mortality. Using pooled 15-year follow-up data, colonoscopy screening effectiveness was estimated assuming that the efficacy of colonoscopy in the proximal colon was similar to that observed in the distal colon in the sigmoidoscopy screening trials. The simulation model was validated using data from Norwegian participants in a colonoscopy screening trial. Results: This analysis included 358 204 individuals (181 971 women [51%]) aged 55 to 64 years at inclusion with a median follow-up time ranging from 15 to 17 years. Compared with usual care, colonoscopy prevented an estimated 50 (95% CI, 42-58) CRC cases per 100 000 person-years, corresponding to 30% incidence reduction (rate ratio, 0.70 [95% CI, 0.66-0.75]), and prevented an estimated 15 (95% CI, 11-19) CRC deaths per 100 000 person-years, corresponding to 32% mortality reduction (rate ratio, 0.68 [95% CI, 0.61-0.76]). The additional benefit of colonoscopy screening compared with sigmoidoscopy was 12 (95% CI, 10-14) fewer CRC cases and 4 (95% CI, 3-5) fewer CRC deaths per 100 000 person-years, corresponding to percentage point reductions of 6.9 (95% CI, 6.0-7.9) for CRC incidence and 7.6 (95% CI, 5.7-9.6) for CRC mortality. The number needed to switch from sigmoidoscopy to colonoscopy screening was 560 (95% CI, 486-661) to prevent 1 CRC case and 1611 (95% CI, 1275-2188) to prevent 1 CRC death. Conclusions and Relevance: The findings of this comparative effectiveness study assessing long-term follow-up after CRC screening suggest that there was an additional preventive effect on CRC incidence and mortality associated with colonoscopy screening compared with sigmoidoscopy screening, but the additional preventive effect was less than what was achieved by introducing sigmoidoscopy screening where no screening existed. The results probably represent the upper limit of what may be achieved with colonoscopy screening compared with sigmoidoscopy screening.

CRC screening with sigmoidoscopy extends life by 110 d; other cancer screening tests do not extend life.

SOURCE CITATION: Bretthauer M, Wieszczy P, Løberg M, et al. Estimated lifetime gained with cancer screening tests: a meta-analysis of randomized clinical trials. JAMA Intern Med. 2023;183:1196-1203. 37639247.

Spatial mapping of colorectal cancer screening uptake and associated factors.

OBJECTIVE: Over the past decades, it has been understood that the availability of screening tests has contributed to a steady decline in incidence of colorectal cancer (CRC). However, it is also seen that there is a geographic disparity in the use of such tests across small areas. The aim of this study is to examine small-area level barrier factors that may impact CRC screening uptake and to delineate coldspot (low uptake of screening) counties in Florida. METHODS: Data on the percentages of county-level CRC screening uptakes in 2016 and county-level barrier factors for screening were obtained from the Florida Department of Health, Division of Public Health Statistics & Performance Management. Bayesian spatial beta models were used to produce posterior probability of deceedance to identify coldspots for CRC screening rates. RESULTS: Unadjusted screening rates using sigmoidoscopy or colonoscopy test ranged from 56.8 to 85%. Bayesian spatial beta models were fitted to the proportion data. At an ecological level, we found that an increasing rate of CRC screening uptake for either of the test types (colon/rectum exam, stool-based test) was strongly associated with a higher health insurance coverage, and lower percentage of population that speak English less than very well (immigration) at county level. Eleven coldspot counties out of 67 total were also identified. CONCLUSION: This study suggests that health insurance disparities in the use of CRC screening tests are an important factor that may need more attention for resource allocation and health policy targeting small areas with low uptake of screening.

Randomized controlled trial of effects of a familiarization video and patient-controlled Entonox inhalation on patient stress levels and clinical efficacy of flexible sigmoidoscopy without analgesia or sedation for investigation of fresh rectal bleeding.

BACKGROUND AND AIM: Flexible sigmoidoscopy (FS) without analgesia or sedation can be unpleasant for patients, resulting in unsatisfactory examinations. Prior familiarization videos (FVs) and intra-procedural Entonox inhalation have shown inconsistent effects. This study investigated their effects on undesirable participant factors (anxiety, stress, discomfort, pain, satisfaction, later unpleasant recall of procedure, and vasovagal reactions) and clinical effectiveness (extent of bowel seen, lesions detected, and procedural/recovery times). METHODS: This cluster-randomized single-center study evaluated 138 participants undergoing FS. There were 46 controls, 49 given access to FV, and 43 access to both FV and self-administered Entonox. Participant factors were measured by self-administered questionnaires, independent nurse assessments, and heart rate variability (HRV) metrics. RESULTS: Questionnaires showed that the FV group was slightly more tense and upset before FS, but knowledge of Entonox availability reduced anxiety. Nonlinear HRV metrics confirmed reduced intra-procedural stress response in the FV/Entonox group compared with controls and FV alone (P < 0.05). Entonox availability allowed more bowel to be examined (P < 0.001) but increased procedure time (P < 0.05), while FV alone had no effect. FV/Entonox participants reported 1 month after FS less discomfort during the procedure. Other comparisons showed no significant differences between treatment groups, although one HRV metric showed some potential to predict vasovagal reactions. CONCLUSIONS: Entonox availability significantly improved clinical effectiveness and caused a slight reduction in undesirable participant factors. The FV alone did not reduce undesirable participant factors or improve clinical effectiveness. Nonlinear HRV metrics recorded effects in agreement with stress reduction and may be useful for prediction of vasovagal events in future studies.

Assessing Guidelines on the Need for Colonoscopy After Initial Flexible Sigmoidoscopy in Young Patients With Outlet-Type Rectal Bleeding.

BACKGROUND: Although young-age-of-onset colorectal cancer is increasing in incidence, lack of screening leads to symptomatic presentation, often with rectal bleeding. Because most cancers in patients younger than 50 years are left-sided, flexible sigmoidoscopy is a reasonable way of investigating bleeding in these patients. OBJECTIVE: To predict which patients undergoing flexible sigmoidoscopy for outlet-type rectal bleeding need a full colonoscopy. DESIGN: Findings at colonoscopy were compared with published indications for colonoscopy after flexible sigmoidoscopy, which were as follows: 1) any number of advanced adenomas defined as a tubular adenoma of >9 mm diameter, a tubulovillous or villous adenoma of any size, or any adenoma with high-grade dysplasia; 2) 3 or more tubular adenomas of any size or histology; 3) any sessile serrated lesion; and 4) 20 or more hyperplastic polyps. SETTING: Charity Hospital with volunteer specialists. PATIENTS: Patients were included if they were younger than 57 years, had outlet-type rectal bleeding, and underwent flexible sigmoidoscopy at least to the descending colon followed by colonoscopy with biopsy of all resected lesions. INTERVENTIONS: Flexible sigmoidoscopy and colonoscopy with excision of all removable lesions. MAIN OUTCOME MEASURES: Findings at colonoscopy. RESULTS: There were 66 patients who had a colonoscopy between 5 and 811 days after sigmoidoscopy and also had complete data. There were 43 men and 23 women with a mean age of 39.5 years. Analysis of flexible sigmoidoscopy criteria for finding proximal high-risk lesions on colonoscopy showed a sensitivity of 76.9%, a specificity of 67.9%, a positive predictive value of 37%, a negative predictive value of 92.3%, and an accuracy of 69.7%. LIMITATIONS: A large number of exclusions for inadequate colonoscopy or inadequate data resulted in a reduced patient number in the study. CONCLUSIONS: Our criteria for follow-up colonoscopy based on the findings at initial flexible sigmoidoscopy in young patients with outlet-type rectal bleeding are reliable enough to be used in routine clinical practice, provided this is audited. See Video Abstract. GUA DE EVALUACIN PARA LA NECESIDAD DE COLONOSCOPIA DESPUS DE UNA SIGMOIDOSCOPIA FLEXIBLE INICIAL EN PACIENTES JVENES CON RECTORRAGIA: ANTECEDENTES:Si bien la edad de aparición temprana del cáncer colorrectal está aumentando en incidencia, la falta de pruebas de detección conduce a una presentación sintomática, a menudo con sangrado rectal. Debido a que la mayoría de los cánceres en pacientes menores de 50 años son del lado izquierdo, la sigmoidoscopia flexible es una forma razonable de investigar el sangrado en estos pacientes.OBJETIVO:Predecir qué pacientes sometidos a sigmoidoscopia flexible por rectorragia necesitan una colonoscopia completa.DISEÑO:Los resultados de la colonoscopia se compararon con las indicaciones publicadas para la colonoscopia después de una sigmoidoscopia flexible. Estos fueron: 1. Cualquier número de adenomas avanzados, definidos como un adenoma tubular > 9 mm, un adenoma tubulovelloso o velloso de cualquier tamaño, o cualquier adenoma con displasia de alto grado. 2. Tres o más adenomas tubulares de cualquier tamaño o histología. 3. Cualquier lesión serrada sésil. 4. Veinte o más pólipos hiperplásicos.ENTORNO CLINICO:Hospital de Caridad con especialistas voluntarios.PACIENTES:Menores de 57 años, con rectorragia, sometidos a sigmoidoscopia flexible al menos hasta el colon descendente, seguida de colonoscopia con biopsia de todas las lesiones resecadas.INTERVENCIONES:sigmoidoscopia flexible y colonoscopia con escisión de todas las lesiones removibles.PRINCIPALES MEDIDAS DE VALORACIÓN:Hallazgos en la colonoscopia.RESULTADOS:66 casos a los que se les realizó una colonoscopia entre 5 y 811 días después de la sigmoidoscopia, que también tenían datos completos. 43 hombres y 23 mujeres con una edad media de 39,5 años. El análisis de los criterios de sigmoidoscopia flexible para encontrar lesiones proximales de alto riesgo en la colonoscopia mostró una sensibilidad del 76,9 %, una especificidad del 67,9 %, un valor predictivo positivo del 37 %, un valor predictivo negativo del 92,3 % y una precisión del 69,7 %.LIMITACIONES:Gran número de exclusiones por colonoscopia inadecuada o datos inadecuados que causan un número reducido de pacientes en el estudio.CONCLUSIÓN:Nuestros criterios para la colonoscopia de seguimiento basados en los hallazgos de la sigmoidoscopia flexible inicial en pacientes jóvenes con rectorragia son lo suficientemente confiables para ser utilizados en la práctica clínica habitual, siempre que se audite. (Traducción- Dr. Ingrid Melo ).

The risk of bleeding and perforation from sigmoidoscopy or colonoscopy in colorectal cancer screening: A systematic review and meta-analyses.

INTRODUCTION: Physical harm from Colorectal Cancer Screening tends to be inadequately measured and reported in clinical trials. Also, studies of ongoing Colorectal Cancer Screening programs have found more frequent and severe physical harm from screening procedures, e.g., bleeding and perforation, than reported in previous trials. Therefore, the objectives of the study were to systematically review the evidence on the risk of bleeding and perforation in Colorectal Cancer Screening. DESIGN: Systematic review with descriptive statistics and random-effects meta-analyses. METHODS: We systematically searched five databases for studies investigating physical harms related to Colorectal Cancer Screening. We assessed the internal and the external validity using the ROBINS-I tool and the GRADE approach. Harm estimates was calculated using mixed Poisson regression models in random-effect meta-analyses. RESULTS: We included 89 studies. Reporting and measurement of harms was inadequate in most studies. In effect, the risk of bias was critical in 97.3% and serious in 98.3% of studies. All GRADE ratings were very low. Based on severe findings with not-critical risk of bias and 30 days follow-up, the risk of bleedings per 100,000 people screened were 8 [2;24] for sigmoidoscopy, 229 [129;408] for colonoscopy following fecal immunochemical test, 68 [39;118] for once-only colonoscopy, and 698 [443;1045] for colonoscopy following any screening tests. The risk of perforations was 88 [56;138] for colonoscopy following fecal immunochemical test and 53 [25;112] for once-only colonoscopy. There were no findings within the subcategory severe perforation with long-term follow-up for colonoscopy following any screening tests and sigmoidoscopy. DISCUSSION: Harm estimates varied widely across studies, reporting and measurement of harms was mostly inadequate, and the risk of bias and GRADE ratings were very poor, collectively leading to underestimation of harm. In effect, we consider our estimates of perforation and bleeding as conservative, highlighting the need for better reporting and measurement in future studies. TRIAL REGISTRATION: PROSPERO registration number: CRD42017058844.

Lower participation among immigrants in colorectal cancer screening in Norway.

Introduction: Organized cancer screening programs should be equally accessible for all groups in society. We assessed differences in participation in colorectal cancer (CRC) screening among different immigrant groups. Methods: Between 2012 and 2019, 140,000 individuals aged 50 to 74 years were randomly invited to sigmoidoscopy or repeated faecal immunochemical test (FIT) in a CRC screening trial. In this study, we included 46,919 individuals invited to sigmoidoscopy and 70,018 invited to the first round of FIT between 2012 and 2017. We examined difference in participation between non-immigrants and immigrants, and within different immigrant groups by geographic area of origin, using logistic regression models, adjusted for several sociodemographic factors and health factors. Results: In total, we included 106,695 non-immigrants and 10,242 immigrants. The participation rate for FIT was 60% among non-immigrants, 58% among immigrants from Western countries and 37% among immigrants from non-Western countries. The participation rate for sigmoidoscopy was 53% among non-immigrants, 48% among immigrants from Western countries and 23% among immigrants from non-Western countries. Compared to non-immigrants, multivariate adjusted odds ratio for non-participation in FIT screening was 1.13 (95% confidence interval 1.04-1.23) and 1.82 (1.69-1.96) for immigrants from Western and non-Western countries. The corresponding numbers in sigmoidoscopy screening were 1.34 (1.21-1.48) and 2.83 (2.55-3.14). The lowest participation was observed in immigrants from Eastern Europe, Northern Africa and Western Asia, and South-Central Asia. Conclusion: Participation in CRC screening in Norway was particularly low among non-Western immigrants, which could put them at increased risk for late stage diagnosis of CRC. Participation was lower in sigmoidoscopy screening than in FIT screening, especially among immigrants from non-Western countries.

Effect of flexible sigmoidoscopy-based screening on colorectal cancer incidence and mortality: an updated systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: Our objective was to estimate the effect of flexible sigmoidoscopy (FS)-based screening on colorectal cancer (CRC) incidence and mortality by conducting an updated meta-analysis of randomized controlled trials (RCTs). METHODS: PubMed, Web of Science, Embase, and Cochrane Library searched for RCTs from database inception to December 2022. The methodological quality of the RCTs was assessed using the Cochrane Collaboration Risk of Bias Tool. RevMan 5.4 was used for this meta-analysis. RESULTS: Four RCTs involving 457, 871 patients were included. This meta-analysis revealed that FS-based screening was associated with a 20% relative risk reduction in CRC incidence [RR = 0.80; 95% CI (0.75, 0.86); P < 0.00001], and a 24% reduction in CRC mortality [RR = 0.76; 95% CI (0.70, 0.82); P < 0.00001]. In addition, this meta-analysis revealed that FS-based screening reduced the incidence[RR = 0.68; 95% CI (0.60, 0.77); P < 0.00001] and mortality[RR = 0.64; 95% CI (0.49, 0.83); P = 0.0007] of distal CRC, but had no significant effect on proximal colon cancer. CONCLUSION: FS-based screening appeared to be effective in reducing distal CRC incidence and mortality in patients at average risk compared to no intervention, but had no significant effect on proximal colon cancer.

Is there a place for sigmoidoscopy in colorectal cancer screening? A systematic review and critical appraisal of cost-effectiveness models.

INTRODUCTION: Screening for colorectal cancer (CRC) is effective in reducing both incidence and mortality. Colonoscopy and stool tests are most frequently used for this purpose. Sigmoidoscopy is an alternative screening measure with a strong evidence base. Due to its distinct characteristics, it might be preferred by subgroups. The aim of this systematic review is to analyze the cost-effectiveness of sigmoidoscopy for CRC screening compared to other screening methods and to identify influencing parameters. METHODS: A systematic literature search for the time frame 01/2010-01/2023 was conducted using the databases MEDLINE, Embase, EconLit, Web of Science, NHS EED, as well as the Cost-Effectiveness Registry. Full economic analyses examining sigmoidoscopy as a screening measure for the general population at average risk for CRC were included. Incremental cost-effectiveness ratios were calculated. All included studies were critically assessed based on a questionnaire for modelling studies. RESULTS: Twenty-five studies are included in the review. Compared to no screening, sigmoidoscopy is a cost-effective screening strategy for CRC. When modelled as a single measure strategy, sigmoidoscopy is mostly dominated by colonoscopy or modern stool tests. When combined with annual stool testing, sigmoidoscopy in 5-year intervals is more effective and less costly than the respective strategies alone. The results of the studies are influenced by varying assumptions on adherence, costs, and test characteristics. CONCLUSION: The combination of sigmoidoscopy and stool testing represents a cost-effective screening strategy that has not received much attention in current guidelines. Further research is needed that goes beyond a narrow focus on screening technology and models different, preference-based participation behavior in subgroups.

Screening for Colorectal Cancer in Asymptomatic Average-Risk Adults: A Guidance Statement From the American College of Physicians (Version 2).

DESCRIPTION: The purpose of this updated guidance statement is to guide clinicians on screening for colorectal cancer (CRC) in asymptomatic average-risk adults. The intended audience is all clinicians. The population is asymptomatic adults at average risk for CRC. METHODS: This updated guidance statement was developed using recently published and critically appraised clinical guidelines from national guideline developers since the publication of the American College of Physicians' 2019 guidance statement, "Screening for Colorectal Cancer in Asymptomatic Average-Risk Adults." The authors searched for national guidelines from the United States and other countries published in English using PubMed and the Guidelines International Network library from 1 January 2018 to 24 April 2023. The authors also searched for updates of guidelines included in the first version of our guidance statement. The Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument was used to assess the quality of eligible guidelines. Two guidelines were selected for adoption and adaptation by raters on the basis of the highest average overall AGREE II quality scores. The evidence reviews and modeling studies for these 2 guidelines were also used to synthesize the evidence of diagnostic test accuracy, effectiveness, and harms of CRC screening interventions and to develop our guidance statements. GUIDANCE STATEMENT 1: Clinicians should start screening for colorectal cancer in asymptomatic average-risk adults at age 50 years. GUIDANCE STATEMENT 2: Clinicians should consider not screening asymptomatic average-risk adults between the ages of 45 to 49 years. Clinicians should discuss the uncertainty around benefits and harms of screening in this population. GUIDANCE STATEMENT 3: Clinicians should stop screening for colorectal cancer in asymptomatic average-risk adults older than 75 years or in asymptomatic average-risk adults with a life expectancy of 10 years or less. GUIDANCE STATEMENT 4A: Clinicians should select a screening test for colorectal cancer in consultation with their patient based on a discussion of benefits, harms, costs, availability, frequency, and patient values and preferences. GUIDANCE STATEMENT 4B: Clinicians should select among a fecal immunochemical or high-sensitivity guaiac fecal occult blood test every 2 years, colonoscopy every 10 years, or flexible sigmoidoscopy every 10 years plus a fecal immunochemical test every 2 years as a screening test for colorectal cancer. GUIDANCE STATEMENT 4C: Clinicians should not use stool DNA, computed tomography colonography, capsule endoscopy, urine, or serum screening tests for colorectal cancer.

Trends in colorectal cancer screening in the United States, 2012 to 2020.

OBJECTIVES: Despite recommendations to increase the uptake of colorectal cancer (CRC) screening, trends in CRC screening vary with sociodemographic status. We aimed to evaluate trends in CRC screening in the US population and subpopulations. METHODS: A total of 1,082,924 participants aged 50 to 75 from five cycles (2012, 2014, 2016, 2018, and 2020) of the Behavioral Risk Factor Surveillance System were involved. Multivariable logistic regression models were performed to evaluate linear trends in CRC screening utilization from 2012 to 2018. Rao-Scott chi-square tests were used to assess the differences in CRC screening utilization between 2018 and 2020. RESULTS: The estimated percentage reporting up-to-date with CRC screening increased significantly (P for trend <0.001), from 62.8% (95% CI, 62.4%-63.2%) in 2012 to 66.7% (95% CI, 66.3%-67.2%) in 2018 and 70.4% (95% CI, 69.8%-71.0%) in 2020, in accordance with 2008 US Preventive Services Task Force recommendations. Trends followed similar patterns in most subgroups, although with different magnitudes in several subgroups, primarily those underweight showed a stable percentage over time (P for trend = 0.170). In 2020, 72.4% of participants reported they were up to date with CRC screening, including the utilization of stool DNA tests and virtual colonoscopy. Colonoscopy was the most commonly used test in 2020 (64.5%), followed by FOBT (12.6%), stool DNA test (5.8%), sigmoidoscopy (3.8%), and virtual colonoscopy (2.7%). CONCLUSIONS: In this nationally representative survey of the US population from 2012 through 2020, the percentage reporting up to date with CRC screening has increased, but not equally among all subgroups.

Increasing the accuracy of colorectal cancer screening.

INTRODUCTION: Colorectal cancer (CRC) is a major health issue, being responsible for nearly 10% of all cancer-related deaths. Since CRC is often an asymptomatic or paucisymptomatic disease until it reaches advanced stages, screening is crucial for the diagnosis of preneoplastic lesions or early CRC. AREAS COVERED: The aim of this review is to summarize the literature evidence on currently available CRC screening tools, with their pros and cons, focusing on the level of accuracy reached by each test over time. We also provide an overview of novel technologies and scientific advances that are currently being investigated and that in the future may represent real game-changers in the field of CRC screening. EXPERT OPINION: We suggest that best screening modalities are annual or biennial FIT and colonoscopy every 10 years. We believe that the introduction of artificial intelligence (AI)-tools in the CRC screening field could lead to a significant improvement of the screening efficacy in reducing CRC incidence and mortality in the future. More resources should be put into implementing CRC programs and support research project to further increase the accuracy of CRC screening tests and strategies.

In adults, sigmoidoscopy screening invitation reduced CRC incidence and related mortality at 15 y.

SOURCE CITATION: Juul FE, Cross AJ, Schoen RE, et al. 15-year benefits of sigmoidoscopy screening on colorectal cancer incidence and mortality: a pooled analysis of randomized trials. Ann Intern Med. 2022;175:1525-33. 36215714.

Association between use of low-dose aspirin and detection of colorectal polyps and cancer in a screening setting.

BACKGROUND: The possible protective effect of aspirin on risk of colorectal cancer (CRC) is still highly debated. METHODS: We used data from Bowel Cancer Screening in Norway, a trial randomizing individuals from general population, aged 50-74 years, to flexible sigmoidoscopy or faecal immunochemical test (FIT), to study the association between aspirin use and detection of CRC and two CRC precursors: adenomas and advanced serrated lesions (ASL). Prescriptions of low-dose aspirin were obtained from Norwegian prescription database. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Among 64,889 screening participants (24,159 sigmoidoscopy, 40,730 FIT), 314 (0.5%) had CRC, 6,208 (9.6%) adenoma and 659 (1.0%) ASL. Overall and short-term use (<3 years) of low-dose aspirin, versus no use, were not associated with any colorectal lesion. Long-term use (≥3 years) was associated with lower detection of CRC (overall OR 0.66, 95%CI 0.46-0.93; sigmoidoscopy: 0.56, 0.33-0.97; FIT: 0.72, 0.45-1.15), adenomas in sigmoidoscopy arm (overall OR 0.95, 95%CI 0.87-1.03; sigmoidoscopy: 0.89, 0.80-0.99; FIT: 1.03, 0.89-1.18), but not ASLs. We did not observe significant differences in the effect of aspirin according to the location of colorectal lesions. CONCLUSION: Our results suggest that long-term use of aspirin might have a protective effect against adenomas and colorectal cancer, but not ASLs.