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Background: Posteromedial meniscal root tears occur when the meniscal root detaches from the tibial plateau, which limits the native functionality of the meniscus, alters tibiofemoral contact forces, and can progress to meniscal extrusion. Untreated meniscal root tears with meniscal extrusion have been associated with significant articular cartilage loss and accelerated progression of osteoarthritis. Recent biomechanical evidence suggests restoring the contact area with the use of a peripheral stabilization suture at the posteromedial aspect of the tibial plateau. Indications: Meniscal root repair with a peripheral stabilization suture is indicated by clinical and radiographic evidence of complete detachment of the posteromedial meniscus root with significant meniscal extrusion outside the joint. Technique Description: This technique uses 2 tunnels for the meniscal root repair as well as a single additional transtibial tunnel for the peripheral stabilization suture. The described technique demonstrates a peripheral release along the meniscocapsular junction to allow the meniscus to be reapproximated to its anatomical attachment site. This is followed by transtibial tunnel preparation to allow suture passage for the meniscal root repair and an additional transtibial tunnel is created for the peripheral stabilization suture. After stabilization of the extruded meniscus, the suture is tied down over a cortical fixation device on the anteromedial tibia. Results: Significant improvement has been reported by clinical studies after the transtibial pullout repair method; however, structural outcomes have shown conflicting results. Kaplan et al reported patients treated with transtibial suture pullout technique with 2 locking cinch sutures had improved clinical outcomes, but increased extrusion of the medial meniscus compared with the preoperative state, whereas Kim et al reported a decrease in meniscal extrusion following pullout suture repair technique. Discussion: Posteromedial meniscus root repair using a peripheral stabilization suture is an effective surgical technique to restore the contact pressures of the knee and limit the amount of meniscal extrusion. This allows for appropriate correction of hoop stress to prevent further cartilage loss and progression of osteoarthritis. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Background: Anterior cruciate ligament (ACL) reconstructions in skeletally immature patients have an increased risk of graft failure and a decreased rate of successful return to sports. Anterior cruciate ligament reconstructions (ACLRs) combined with lateral extra-articular tenodesis (LET) procedures are reported to limit anterolateral rotary instability of the knee, decreasing tension on the ACL graft. However, the open physes found in pediatric patients present unique challenges for ACLR. This video demonstrates a technique to avoid the femoral physis and necessary precautions for performing an ACLR with LET in a skeletally immature patient. Indications: The indications for combined ACLR and LET, as opposed to ACLR alone, mainly center on the risk factors for graft failure. These include the following: posterior tibial slope >12°, revision ACLR, high-grade pivot shift on physical examination, meniscal deficiency, generalized ligamentous hyperlaxity, and—especially pertinent to this procedure—skeletally immature patients. Technique Description: Standard plain radiographs and long-leg alignment films, along with a magnetic resonance imaging (MRI) study, are necessary to assess for malalignment, bone age, and concomitant meniscal and chondral pathology. This technique describes the senior author’s preferred technique for pediatric ACLR with LET. The senior author’s preferred order of operations includes performing the autologous hamstring graft harvest and LET before performing the diagnostic arthroscopy. This is followed by the intra-articular work including the ACLR. It is also the senior author’s preference to perform physeal-sparing femoral tunnels, using fluoroscopy for tunnel placement. Results: Getgood et al reported that an ACLR with an LET in young patients with a high risk of graft failure had a significant reduction in graft rupture compared to an ACLR alone. Furthermore, Noyes et al reported a significantly lower rate of graft failure and a higher rate of return to sports in those who received LET in addition to ACLR compared with those who received ACLR alone. Discussion: An ACLR combined with an LET has been reported to reduce graft failure rates and improve clinical outcomes in high-risk patients. An ACLR with LET may also be considered in skeletally immature patients with appropriate indications and extra precautions to avoid growth arrest or deformity. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Background: Direct-to-consumer promotion of lung cancer screening has increased, especially low-dose computed tomography (CT). However, screening exposes healthy persons to potential harms, and cumulative false-positive rates for low-dose CT have never been formally reported.Objective: To quantify the cumulative risk that a person who participated in a 1- or 2-year lung cancer screening examination would receive at least 1 false-positive result, as well as rates of unnecessary diagnostic procedures.Design: Randomized, controlled trial of low-dose CT versus chest radiography. (ClinicalTrials.gov registration number: NCT00006382)Setting: Feasibility study for the ongoing National Lung Screening Trial.Patients: Current or former smokers, aged 55 to 74 years, with a smoking history of 30 pack-years or more and no history of lung cancer (n = 3190).Intervention: Random assignment to low-dose CT or chest radiography with baseline and 1 repeated annual screening; 1-year follow-up after the final screening. Randomization was centralized and stratified by age, sex, and study center.Measurements: False-positive screenings, defined as a positive screening with a completed negative work-up or 12 months or more of follow-up with no lung cancer diagnosis.Results: By using a Kaplan-Meier analysis, a person's cumulative probability of 1 or more false-positive low-dose CT examinations was 21% (95% CI, 19% to 23%) after 1 screening and 33% (CI, 31% to 35%) after 2. The rates for chest radiography were 9% (CI, 8% to 11%) and 15% (CI, 13% to 16%), respectively. A total of 7% of participants with a false-positive low-dose CT examination and 4% with a false-positive chest radiography had a resulting invasive procedure.Limitations: Screening was limited to 2 rounds. Follow-up after the second screening was limited to 12 months. The false-negative rate is probably an underestimate.Conclusion: Risks for false-positive results on lung cancer screening tests are substantial after only 2 annual examinations, particularly for low-dose CT. Further study of resulting economic, psychosocial, and physical burdens of these methods is warranted.Primary Funding Source: National Cancer Institute. [ABSTRACT FROM AUTHOR]

Competing Interests: Competing interests: We have read and understood BMJ policy on declaration of interests and declare the following: AP holds grant funding from the NIHR School for Primary Care Research; DR reports consultancy fees from Mercy Bioanalytics and the National Cancer Institute for advisory work in discovery research on cancer screening tests; EGG, BSK, and SW are current members of the scientific committee for Preventing Overdiagnosis, for which they receive no financial support.

Cancer screening has the potential to decrease mortality from several common cancer types. The first cancer screening programme in China was initiated in 1958 and the Cancer High Incidence Fields established in the 1970s have provided an extensive source of information for national cancer screening programmes. From 2012 onwards, four ongoing national cancer screening programmes have targeted eight cancer types: cervical, breast, colorectal, lung, oesophageal, stomach, liver, and nasopharyngeal cancers. By synthesising evidence from pilot screening programmes and population-based studies for various screening tests, China has developed a series of cancer screening guidelines. Nevertheless, challenges remain for the implementation of a fully successful population-based programme. The aim of this Review is to highlight the key milestones and the current status of cancer screening in China, describe what has been achieved to date, and identify the barriers in transitioning from evidence to implementation. We also make a set of implementation recommendations on the basis of the Chinese experience, which might be useful in the establishment of cancer screening programmes in other countries., Competing Interests: Declaration of interests KC is co-Principal Investigator of an investigator-initiated trial of cervical screening, Compass, run by the Australian Centre for Prevention of Cervical Cancer (ACPCC), a government-funded not-for-profit charity. Compass receives infrastructural support from the Australian government and the ACPCC has received equipment and a funding contribution from Roche Molecular Diagnostics, USA. KC is also co-Principal Investigator on a major implementation programme, Elimination of Cervical Cancer in the Western Pacific, which has received support from the Minderoo Foundation, and equipment donations from Cepheid. All other authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

"Screening" is a search for preclinical, asymptomatic disease, including cancer. Widespread cancer screening has led to large increases in early-stage cancers and pre-cancers. Ubiquitous public messages emphasize the potential benefits to screening for these lesions based on the underlying assumption that treating cancer at early stages before spread to other organs should make it easier to treat and cure, using more tolerable interventions. The intuition is so strong that public campaigns are sometimes launched without conducting definitive trials directly comparing screening to usual care. An effective cancer screening test should not only increase the incidence of early-stage preclinical disease but should also decrease the incidence of advanced and metastatic cancer, as well as a subsequent decrease in cancer-related mortality. Otherwise, screening efforts may be uncovering a reservoir of non-progressive and very slowly progressive lesions that were not destined to cause symptoms or suffering during the person's remaining natural lifespan: a phenomenon known as "overdiagnosis." We provide here a qualitative review of cancer overdiagnosis and discuss specific examples due to extensive population-based screening, including neuroblastoma, prostate cancer, thyroid cancer, lung cancer, melanoma, and breast cancer. The harms of unnecessary diagnosis and cancer therapy call for a balanced presentation to people considering undergoing screening, even with a test of accepted benefit, with a goal of informed decision-making. We also discuss proposed strategies to mitigate the adverse sequelae of overdiagnosis.

Competing Interests: Competing interests: We have read and understood BMJ policy on declaration of interests and have no relevant interests to declare. The authors alone are responsible for the views expressed and they do not necessarily represent the views, decisions, or policies of the institutions with which they are affiliated. Provenance and peer review: Not commissioned; externally peer reviewed.

Background: Cancer centers have a responsibility to help patients manage the costs of their cancer treatment. This article describes the availability of financial navigation services within the National Cancer Institute (NCI)-designated cancer centers., Methods: Data were obtained from the NCI Survey of Financial Navigation Services and Research, an online survey administered to NCI-designated cancer centers from July to September 2019. Of the 62 eligible centers, 57 completed all or most of the survey, for a response rate of 90.5%., Results: Nearly all cancer centers reported providing help with applications for pharmaceutical assistance programs and medical discounts (96.5%), health insurance coverage (91.2%), assistance with nonmedical costs (96.5%), and help understanding medical bills and out-of-pocket costs (85.9%). Although other services were common, in some cases they were only available to certain patients. These services included direct financial assistance with medical and nonmedical costs and referrals to outside organizations for financial assistance. The least common services included medical debt management (63.2%), detailed discussions about the cost of treatment (54.4%), and guidance about legal protections (50.1%). Providing treatment cost transparency to patients was reported as a common challenge: 71.9% of centers agreed or strongly agreed that it is difficult to determine how much a cancer patient's treatment will cost, and 70.2% of oncologists are reluctant to discuss financial issues with patients., Conclusions: Cancer centers provide many financial services and resources. However, there remains a need to build additional capacity to deliver comprehensive financial navigation services and to understand the extent to which patients are referred and helped by these services., (Published by Oxford University Press 2021. This work is written by US Government employees and is in the public domain in the US.)

Patients, practitioners, and policy makers are increasingly concerned about the delivery of ineffective or low-value clinical practices in cancer care settings. Research is needed on how to effectively deimplement these types of practices from cancer care. In this commentary, we spotlight the National Cancer Institute Community Oncology Research Program (NCORP), a national network of community oncology practices, and elaborate on how it is an ideal infrastructure for conducting rigorous, real-world research on deimplementation. We describe key multilevel issues that affect deimplementation and also serve as a guidepost for developing strategies to drive deimplementation. We describe optimal study designs for testing deimplementation strategies and elaborate on how and why the NCORP network is uniquely positioned to conduct rigorous and impactful deimplementation trials. The number and diversity of affiliated community oncology care sites, coupled with the overall objective of improving cancer care delivery, make the NCORP an opportune infrastructure for advancing deimplementation research while simultaneously improving the care of millions of cancer patients nationwide., (Published by Oxford University Press 2021. This work is written by US Government employees and is in the public domain in the US.)

We review simple methods for evaluating 4 types of biomarkers. First, we discuss the evaluation of surrogate endpoint biomarkers (to shorten a randomized trial) using 2 statistical and 3 biological criteria. Second, we discuss the evaluation of prognostic biomarkers (to predict the risk of disease) by comparing data collection costs with the anticipated net benefit of risk prediction. Third, we discuss the evaluation of predictive markers (to search for a promising subgroup in a randomized trial) using a multivariate subpopulation treatment effect pattern plot involving a risk difference or responders-only benefit function. Fourth, we discuss the evaluation of cancer screening biomarkers (to predict cancer in asymptomatic persons) using methodology to substantially reduce the sample size with stored specimens., Competing Interests: Declaration of Conflicting Interests:The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2020.)

Advances in cancer screening methods have opened avenues for incidental findings and cancer overdiagnosis. We performed a secondary analysis of the National Lung Screening Trial (enrollment from 2002-2004), a randomized controlled trial comparing low-dose computed tomography (LDCT; n = 26,722) with chest radiography (CXR; n = 26,732) for lung cancer detection, to examine incidental findings related to thyroid cancer (ThCa). Three screening rounds were included, and median follow-up was 6.6 years for LDCT and 6.5 years for CXR. Radiologists reported lung and non-lung-related abnormalities. In the LDCT arm, 5.7%, 4.7%, and 4.5% of participants had abnormalities above the diaphragm (AADs) detected at baseline, year 1, and year 2, respectively, compared with 2.3%, 1.5%, and 1.3% in the CXR arm. In the LDCT arm, 205 AADs (7.0%) were thyroid-related. Overall, 60 ThCas were reported, 35 in the LDCT arm and 25 in the CXR arm (P = 0.2). In the LDCT arm, participants with a prior AAD had a 7.8-fold increased risk (95% confidence interval: 4.0, 15.1) of ThCa compared with those who did not have an AAD. Early and persistent excess of ThCas diagnosed earlier in the LDCT arm suggests overdiagnosis. The use of sensitive screening modalities for early detection of lung cancer might result in the discovery of thyroid incidentalomas., (Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2019. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

For cancer screening to be successful, it should primarily detect cancers with lethal potential or their precursors early, leading to therapy that reduces mortality and morbidity. Screening programmes have been successful for colon and cervical cancers, where subsequent surgical removal of precursor lesions has resulted in a reduction in cancer incidence and mortality. However, many types of cancer exhibit a range of heterogeneous behaviours and variable likelihoods of progression and death. Consequently, screening for some cancers may have minimal impact on mortality and may do more harm than good. Since the implementation of screening tests for certain cancers (for example, breast and prostate cancers), a spike in incidence of in situ and early-stage cancers has been observed, but a link to reduction in cancer-specific mortality has not been as clear. It is difficult to determine how many of these mortality reductions are due to screening and how many are due to improved treatments of tumours. In cancers with lower incidence but high mortality (for example, pancreatic cancer), screening has focused on high-risk populations, but challenges similar to those for general population screening remain, particularly with regard to finding lesions with difficult-to-characterize malignant potential (for example, intraductal papillary mucinous neoplasms). More sensitive screening methods are detecting smaller and smaller lesions, but this has not been accompanied by a comparable reduction in the incidence of invasive cancers. In this Opinion article, we focus on the contribution of screening in general and high-risk populations to overdiagnosis, the effects of overdiagnosis on patients and emerging strategies to reduce overdiagnosis of indolent cancers through an understanding of tumour heterogeneity, the biology of how cancers evolve and progress, the molecular and cellular features of early neoplasia and the dynamics of the interactions of early lesions with their surrounding tissue microenvironment.

The recent pace, extent, and impact of paradigm-changing cancer prevention science has been remarkable. The American Association for Cancer Research (AACR) convened a 3-day summit, aligned with five research priorities: (i) Precancer Atlas (PCA). (ii) Cancer interception. (iii) Obesity-cancer linkage, a global epidemic of chronic low-grade inflammation. (iv) Implementation science. (v) Cancer disparities. Aligned with these priorities, AACR co-led the Lancet Commission to formally endorse and accelerate the NCI Cancer Moonshot program, facilitating new global collaborative efforts in cancer control. The expanding scope of creative impact is perhaps most startling-from NCI-funded built environments to AACR Team Science Awarded studies of Asian cancer genomes informing global primary prevention policies; cell-free epigenetic marks identifying incipient neoplastic site; practice-changing genomic subclasses in myeloproliferative neoplasia (including germline variant tightly linked to JAK2 V617F haplotype); universal germline genetic testing for pancreatic cancer; and repurposing drugs targeting immune- and stem-cell signals (e.g., IL-1β, PD-1, RANK-L) to cancer interception. Microbiota-driven IL-17 can induce stemness and transformation in pancreatic precursors (identifying another repurposing opportunity). Notable progress also includes hosting an obesity special conference (connecting epidemiologic and molecular perspectives to inform cancer research and prevention strategies), co-leading concerted national implementation efforts in HPV vaccination, and charting the future elimination of cancer disparities by integrating new science tools, discoveries and perspectives into community-engaged research, including targeted counter attacks on e-cigarette ad exploitation of children, Hispanics and Blacks. Following this summit, two unprecedented funding initiatives were catalyzed to drive cancer prevention research: the NCI Cancer Moonshot (e.g., PCA and disparities); and the AACR-Stand Up To Cancer bold "Cancer Interception" initiative., (©2018 American Association for Cancer Research.)

Screening is vital to reducing morbidity and mortality due to cancer. A primary cause of poor survival is that many cancers are detected late and often after they have metastasized to distant sites. Therapies, therefore, become challenging for late-stage disease and are not successful for nearly all cancer types. The mortality rates from cancers where screening tools are available are lower than from cancers for which no viable screening tools exist. Even for cancers where screening tools currently exist, there is room for improvement, either in the accuracy of the tests or in increasing widespread use of screening by making the tests less invasive. For instance, despite widely available screening methods that can detect early-stage colon cancer or its precursors, only approximately 40% of newly diagnosed colon cancers are localized. It is a challenge to develop screening tests that are not only highly sensitive but also highly specific, to avoid putting patients through unnecessary biopsies and treatment. Biomarkers have great potential to improve the existing diagnostic accuracies of screening modalities and substitute invasive screening methods with noninvasive methodologies using bodily fluids such as plasma, serum, saliva, urine, etc. Biomarkers are defined by the National Institutes of Health as "a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention." In this commentary, we discuss important measures that could be taken to increase the chances of bringing biomarkers to clinical fruition., (Published by Elsevier Inc.)

Background: Screening tests are typically evaluated for a single disease, but multiple tests for multiple diseases are performed in practice. The Prostate, Lung, Colorectal and Ovarian (PLCO) cancer screening trial assessed testing for four cancers simultaneously and can be viewed as a multiphasic cancer intervention. This paper presents overall and multiphasic findings of this trial., Methods: The PLCO trial was a randomized multi-center trial conducted at ten screening centers in the US. Participants were 76,682 men and 78,215 women ages 55 - 74 and free of the target cancers at trial entry. Screening tests were PSA and digital rectal examination for prostate cancer, chest x-ray for lung cancer, flexible sigmoidoscopy for colorectal cancer, CA125 and transvaginal ultrasound for ovarian cancer. Outcomes and harms of screening were assessed including compliance, test results, incidence, mortality, false positives and overdiagnosis., Results: Screening compliance was 82%, 72,820 (8%) of 906,064 exams were positive, the overall PPV was 4.2% and the cancer detection rate was 3.38/1000. A mortality reduction was observed only for colorectal cancer (RR 0.72, 95% CI 0.61 - 0.85) with no effect on all-cause mortality. Ninety-six percent of positive exams were falsely positive and there was a suggestion of overdiagnosis of prostate and possibly ovarian cancers. Multiphasic testing resulted in 7374 men and 2748 women experiencing multiple false positive results from multiple types of tests., Conclusion: Multiphasic cancer screening led to reduced mortality for one target cancer and imposed a burden on the health care system that included substantial false positives and likely overdiagnosis., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Objective To provide evidence about the performance characteristics and consequences of bimanual ovarian palpation. Setting and methods The Prostate, Lung, Colorectal and Ovarian cancer screening trial randomized 154,900 individuals to either an intervention or control arm. Enrolled eligible participants were aged 55-74, had no history of trial cancers, and no current treatment for cancer. Intervention arm women received CA-125 tests and transvaginal ultrasound. Bimanual ovarian palpation was offered annually during the first four years of the trial. Bimanual ovarian palpation-specific sensitivity and specificity were calculated, as were rates of diagnostic procedures and resulting complications following positive bimanual ovarian palpation screens. Results A total of 20,872 women received at least one bimanual ovarian palpation, with 50,498 total bimanual ovarian palpation examinations performed. The sensitivity and specificity of bimanual ovarian palpation were 5.1% (2/39) and 99.0% (49,957/50,459), respectively; no cases were detected by bimanual ovarian palpation alone. Rates for most follow-up procedures for abnormal results in women without ovarian cancer were higher among the group with another screening test positive, except for pelvic exam, where rates were similar. No complications were reported in the bimanual ovarian palpation-only positive group. Conclusion Low sensitivity of bimanual ovarian palpation alone and in combination with other tests argue against using bimanual ovarian palpation as a screening test for ovarian cancer in asymptomatic women.

Introduction Renal cancer incidence has increased markedly in the United States in recent decades, largely due to incidentally detected tumours from computed tomography imaging. Here, we analyze the potential for low-dose computed tomography lung cancer screening to detect renal cancer. Methods The National Lung Screening Trial randomized subjects to three annual screens with either low-dose computed tomography or chest X-ray. Eligibility criteria included 30 + pack-years, current smoking or quit within 15 years, and age 55-74. Subjects were followed for seven years. Low-dose computed tomography screening forms collected information on lung cancer and non-lung cancer abnormalities, including abnormalities below the diaphragm. A reader study was performed on a sample of National Lung Screening Trial low-dose computed tomography images assessing presence of abnormalities below the diaphragms and abnormalities suspicious for renal cancer. Results There were 26,722 and 26,732 subjects enrolled in the low-dose computed tomography and chest X-ray arms, respectively, and there were 104 and 85 renal cancer cases diagnosed, respectively (relative risk = 1.22, 95% CI: 0.9-1.5). From 75,126 low-dose computed tomography screens, there were 46 renal cancer diagnoses within one year. Abnormalities below the diaphragm rates were 39.1% in screens with renal cancer versus 4.1% in screens without (P < 0.001). Cases with abnormalities below the diaphragms had shorter median time to diagnosis than those without (71 vs. 160 days, P = 0.004). In the reader study, 64% of renal cancer cases versus 13% of non-cases had abnormalities below the diaphragms; 55% of cases and 0.8% of non-cases had a finding suspicious for renal cancer (P < 0.001). Conclusion Low-dose computed tomography screens can potentially detect renal cancers. The benefits to harms tradeoff of incidental detection of renal tumours on low-dose computed tomography is unknown.

Background: Two large-scale prostate cancer screening trials using prostate-specific antigen (PSA) have given conflicting results in terms of the efficacy of such screening. One of those trials, the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, previously reported outcomes with 13 years of follow-up. This study presents updated findings from the PLCO trial., Methods: The PLCO trial randomized subjects from 1993 to 2001 to an intervention or control arm. Intervention-arm men received annual PSA tests for 6 years and digital rectal examinations for 4 years. This study used a linkage with the National Death Index to extend mortality follow-up to a maximum of 19 years after randomization., Results: Men were randomized to the intervention arm (n = 38,340) or the control arm (n = 38,343). The median follow-up time was 14.8 years (25th/75th, 12.7/16.5 years) in the intervention arm and 14.7 years (25th/75th, 12.6/16.4 years) in the control arm. There were 255 deaths from prostate cancer in the intervention arm and 244 deaths from prostate cancer in the control arm; this meant a rate ratio (RR) of 1.04 (95% confidence interval [CI], 0.87-1.24). The RR for all-cause mortality was 0.977 (95% CI, 0.950-1.004). It was estimated that 86% of the men in the control arm and 99% of the men in the intervention arm received any PSA testing during the trial, and the estimated yearly screening-phase PSA testing rates were 46% and 84%, respectively., Conclusions: Extended follow-up of the PLCO trial over a median of 15 years continues to indicate no reduction in prostate cancer mortality for the intervention arm versus the control arm. Because of the high rate of control-arm PSA testing, this finding can be viewed as showing no benefit of organized screening versus opportunistic screening. Cancer 2017;123:592-599. © 2016 American Cancer Society., (© 2016 This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

In late 2015, the NCI Division of Cancer Prevention convened cancer prevention research experts and stakeholders to discuss the current state of cancer prevention research, identify key prevention research priorities for the NCI, and identify studies that could be conducted within the NCI Community Oncology Research Program. Goals included identifying cancer prevention research opportunities offering the highest return on investment, exploring the concept of precision prevention and what is needed to advance this area of research, and identifying possible targets for prevention. Four study populations were considered for cancer prevention research: healthy people, those at increased risk for a specific cancer, people with preneoplastic lesions, and children, adolescents, and young adults. Priorities that emerged include screening (e.g., surveillance intervals, tomosynthesis vs. digital mammography), a pre-cancer genome atlas (PreTCGA), HPV vaccines, immunoprevention of noninfectious origins, and overdiagnosis. Challenges exist, as the priority list is ambitious and potentially expensive. Clinical trials need to be carefully designed to include and maximize prospective tissue collection. Exploring existing cofunding mechanisms will likely be necessary. Finally, relationships with a new generation of physician specialists will need to be cultivated to reach the target populations. Cancer Prev Res; 10(2); 99-107. ©2016 AACR., Competing Interests: The authors declare no potential conflicts of interest., (©2016 American Association for Cancer Research.)

In this review, we address selected areas that are central to the state-of-the-art of cancer prevention science. The emphasis on prevention as a viable and critical approach to decreasing cancer mortality has gained traction in recent years, evidenced by its inclusion in the US Vice President's Cancer Initiative (also termed 'Moonshot'). Cancer prevention occurs by arresting, slowing down, or reversing the carcinogenic process before invasion into surrounding tissue or by avoiding or blocking causative exposure. An important challenge is to identify individuals who will benefit most from preventive interventions with the least possible harm. Preventive interventions range from avoiding known carcinogens (e.g., tobacco or asbestos) to intervening with anticarcinogenic strategies (behavioral modifications , such as diet and exercise; medications; nutritional agents; and vaccination against causative agents). Here, we focus on active intervention with measures involving pharmaceutical and immunological agents.

Background: The Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial originally reported no mortality benefit of ovarian cancer screening after a median of 12.4years of follow-up. The UKCTOCS screening trial failed to show a statistically significant mortality reduction in the primary analysis but reported an apparent increased mortality benefit in trial years 7-14 compared to 0-7. Here we report an updated analysis of PLCO with extended mortality follow-up., Methods: Participants were randomized from 1993 to 2001 at ten U.S. centers to an intervention or usual care arm. Intervention arm women were screened for ovarian cancer with annual trans-vaginal ultrasound (TVU) (4years) and CA-125 (6years), with a fixed cutoff at 35U/mL for CA-125. The original follow-up period was for up to 13years (median follow-up 12.4years); in this analysis follow-up for mortality was extended by up to 6years., Results: 39,105 (intervention) and 39,111 (usual care) women were randomized, of which 34,253 and 34,304, respectively, had at least one ovary at baseline. Median follow-up was 14.7years in each arm and maximum follow-up 19.2years in each arm. A total of 187 (intervention) and 176 (usual care) deaths from ovarian cancer were observed, for a risk-ratio of 1.06 (95% CI: 0.87-1.30). Risk-ratios were similar for study years 0-7 (RR=1.04), 7-14 (RR=1.06) and 14+ (RR=1.09). The risk ratio for all-cause mortality was 1.01 (95% CI: 0.97-1.05). Ovarian cancer specific survival was not significantly different across trial arms (p=0.16)., Conclusion: Extended follow-up of PLCO indicated no mortality benefit from screening for ovarian cancer with CA-125 and TVU., Competing Interests: Statement The authors report no conflicts of interest., (Published by Elsevier Inc.)

Background: The goal of screening mammography is to detect small malignant tumors before they grow large enough to cause symptoms. Effective screening should therefore lead to the detection of a greater number of small tumors, followed by fewer large tumors over time., Methods: We used data from the Surveillance, Epidemiology, and End Results (SEER) program, 1975 through 2012, to calculate the tumor-size distribution and size-specific incidence of breast cancer among women 40 years of age or older. We then calculated the size-specific cancer case fatality rate for two time periods: a baseline period before the implementation of widespread screening mammography (1975 through 1979) and a period encompassing the most recent years for which 10 years of follow-up data were available (2000 through 2002)., Results: After the advent of screening mammography, the proportion of detected breast tumors that were small (invasive tumors measuring <2 cm or in situ carcinomas) increased from 36% to 68%; the proportion of detected tumors that were large (invasive tumors measuring ≥2 cm) decreased from 64% to 32%. However, this trend was less the result of a substantial decrease in the incidence of large tumors (with 30 fewer cases of cancer observed per 100,000 women in the period after the advent of screening than in the period before screening) and more the result of a substantial increase in the detection of small tumors (with 162 more cases of cancer observed per 100,000 women). Assuming that the underlying disease burden was stable, only 30 of the 162 additional small tumors per 100,000 women that were diagnosed were expected to progress to become large, which implied that the remaining 132 cases of cancer per 100,000 women were overdiagnosed (i.e., cases of cancer were detected on screening that never would have led to clinical symptoms). The potential of screening to lower breast cancer mortality is reflected in the declining incidence of larger tumors. However, with respect to only these large tumors, the decline in the size-specific case fatality rate suggests that improved treatment was responsible for at least two thirds of the reduction in breast cancer mortality., Conclusions: Although the rate of detection of large tumors fell after the introduction of screening mammography, the more favorable size distribution was primarily the result of the additional detection of small tumors. Women were more likely to have breast cancer that was overdiagnosed than to have earlier detection of a tumor that was destined to become large. The reduction in breast cancer mortality after the implementation of screening mammography was predominantly the result of improved systemic therapy.

Several important lessons have been learnt from our experiences in screening for various cancers. Screening programmes for cervical and colorectal cancers have had the greatest success, probably because these cancers are relatively homogenous, slow-growing, and have identifiable precursors that can be detected and removed; however, identifying the true obligate precursors of invasive disease remains a challenge. With regard to screening for breast cancer and for prostate cancer, which focus on early detection of invasive cancer, preferential detection of slower-growing, localized cancers has occurred, which has led to concerns about overdiagnosis and overtreatment; programmes for early detection of invasive lung cancers are emerging, and have faced similar challenges. A crucial consideration in screening for breast, prostate, and lung cancers is their remarkable phenotypic heterogeneity, ranging from indolent to highly aggressive. Efforts have been made to address the limitations of cancer-screening programmes, providing an opportunity for cross-disciplinary learning and further advancement of the science. Current innovations are aimed at identifying the individuals who are most likely to benefit from screening, increasing the yield of consequential cancers on screening and biopsy, and using molecular tests to improve our understanding of disease biology and to tailor treatment. We discuss each of these concepts and outline a dynamic framework for continuous improvements in the field of cancer screening.

Many cancers offer an extended window of opportunity for early detection and therapeutic intervention that could lead to a reduction in cause-specific mortality. The pursuit of early detection in screening settings has resulted in decreased incidence and mortality for some cancers (e.g., colon and cervical cancers), and increased incidence with only modest or no effect on cause-specific mortality in others (e.g., breast and prostate). Whereas highly sensitive screening technologies are better at detecting a number of suspected "cancers" that are indolent and likely to remain clinically unimportant in the lifetime of a patient, defined as overdiagnosis, they often miss cancers that are aggressive and tend to present clinically between screenings, known as interval cancers. Unrecognized overdiagnosis leads to overtreatment with its attendant (often long-lasting) side effects, anxiety, and substantial financial harm. Existing methods often cannot differentiate indolent lesions from aggressive ones or understand the dynamics of neoplastic progression. To correctly identify the population that would benefit the most from screening and identify the lesions that would benefit most from treatment, the evolving genomic and molecular profiles of individual cancers during the clinical course of progression or indolence must be investigated, while taking into account an individual's genetic susceptibility, clinical and environmental risk factors, and the tumor microenvironment. Practical challenges lie not only in the lack of access to tissue specimens that are appropriate for the study of natural history, but also in the absence of targeted research strategies. This commentary summarizes the recommendations from a diverse group of scientists with expertise in basic biology, translational research, clinical research, statistics, and epidemiology and public health professionals convened to discuss research directions. J. Cell. Physiol. 231: 1870-1875, 2016. © 2015 Wiley Periodicals, Inc., (© 2015 Wiley Periodicals, Inc.)

Background: Annual low-dose CT screening for lung cancer has been recommended for high-risk individuals, but the necessity of yearly low-dose CT in all eligible individuals is uncertain. This study examined rates of lung cancer in National Lung Screening Trial (NLST) participants who had a negative prevalence (initial) low-dose CT screen to explore whether less frequent screening could be justified in some lower-risk subpopulations., Methods: We did a retrospective cohort analysis of data from the NLST, a randomised, multicentre screening trial comparing three annual low-dose CT assessments with three annual chest radiographs for the early detection of lung cancer in high-risk, eligible individuals (aged 55-74 years with at least a 30 pack-year history of cigarette smoking, and, if a former smoker, had quit within the past 15 years), recruited from US medical centres between Aug 5, 2002, and April 26, 2004. Participants were followed up for up to 5 years after their last annual screen. For the purposes of this analysis, our cohort consisted of all NLST participants who had received a low-dose CT prevalence (T0) screen. We determined the frequency, stage, histology, study year of diagnosis, and incidence of lung cancer, as well as overall and lung cancer-specific mortality, and whether lung cancers were detected as a result of screening or within 1 year of a negative screen. We also estimated the effect on mortality if the first annual (T1) screen in participants with a negative T0 screen had not been done. The NLST is registered with ClinicalTrials.gov, number NCT00047385., Findings: Our cohort consisted of 26 231 participants assigned to the low-dose CT screening group who had undergone their T0 screen. The 19 066 participants with a negative T0 screen had a lower incidence of lung cancer than did all 26 231 T0-screened participants (371·88 [95% CI 337·97-408·26] per 100 000 person-years vs 661·23 [622·07-702·21]) and had lower lung cancer-related mortality (185·82 [95% CI 162·17-211·93] per 100 000 person-years vs 277·20 [252·28-303·90]). The yield of lung cancer at the T1 screen among participants with a negative T0 screen was 0·34% (62 screen-detected cancers out of 18 121 screened participants), compared with a yield at the T0 screen among all T0-screened participants of 1·0% (267 of 26 231). We estimated that if the T1 screen had not been done in the T0 negative group, at most, an additional 28 participants in the T0 negative group would have died from lung cancer (a rise in mortality from 185·82 [95% CI 162·17-211·93] per 100 000 person-years to 212·14 [186·80-239·96]) over the course of the trial., Interpretation: Participants with a negative low-dose CT prevalence screen had a lower incidence of lung cancer and lung cancer-specific mortality than did all participants who underwent a prevalence screen. Because overly frequent screening has associated harms, increasing the interval between screens in participants with a negative low-dose CT prevalence screen might be warranted., Funding: None., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

In some two-arm randomized trials, some participants receive the treatment assigned to the other arm as a result of technical problems, refusal of a treatment invitation, or a choice of treatment in an encouragement design. In some before-and-after studies, the availability of a new treatment changes from one time period to this next. Under assumptions that are often reasonable, the latent class instrumental variable (IV) method estimates the effect of treatment received in the aforementioned scenarios involving all-or-none compliance and all-or-none availability. Key aspects are four initial latent classes (sometimes called principal strata) based on treatment received if in each randomization group or time period, the exclusion restriction assumption (in which randomization group or time period is an instrumental variable), the monotonicity assumption (which drops an implausible latent class from the analysis), and the estimated effect of receiving treatment in one latent class (sometimes called efficacy, the local average treatment effect, or the complier average causal effect). Since its independent formulations in the biostatistics and econometrics literatures, the latent class IV method (which has no well-established name) has gained increasing popularity. We review the latent class IV method from a clinical and biostatistical perspective, focusing on underlying assumptions, methodological extensions, and applications in our fields of obstetrics and cancer research., (Copyright © 2015 John Wiley & Sons, Ltd.)

Objective: To investigate the capability of various study designs to determine the sensitivity of a disease screening test., Methods: Quantities that can be calculated from these designs were derived and examined for their relationship to true sensitivity (the ability to detect unrecognized disease that would surface clinically in the absence of screening) and overdiagnosis., Results: To examine the sensitivity of one test, the single cohort design, in which all participants receive the test, is particularly weak, providing only an upper bound on the true sensitivity, and yields no information about overdiagnosis. A randomized design, with one control arm and participants tested in the other, that includes sufficient post-screening follow-up, allows calculation of bounds on, and an approximation to, true sensitivity and also determination of overdiagnosis. Without follow-up, bounds on the true sensitivity can be calculated. To compare two tests, the single cohort paired design in which all participants receive both tests is precarious. The three arm randomized design with post screening follow-up is preferred, yielding an approximation to the true sensitivity, bounds on the true sensitivity, and the extent of overdiagnosis of each test. Without post screening follow-up, bounds on the true sensitivities can be calculated. When an unscreened control arm is not possible, the two-arm randomized design is recommended. Individual test sensitivities cannot be determined, but with sufficient post-screening follow-up, an order relationship can be established, as can the difference in overdiagnosis between the two tests., (© The Author(s) 2015.)

Background: Based on current recommendations, 30+ pack-years of smoking are required for eligibility for low-dose CT (LDCT) lung cancer screening; former smokers must have quit within 15 years. We investigated whether current smokers with 20 to 29 pack-years have similar lung cancer risks as eligible former smokers and also whether they have a different demographic profile., Methods: The Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) was a randomly assigned screening trial of subjects age 55 to 74 years with chest radiographs (CXR) used for lung cancer. Subjects completed a baseline questionnaire containing smoking history questions. Cox proportional hazards models, adjusted for age and sex, were utilized to estimate hazard ratios (HRs) for various smoking history groups. Next, we utilized the National Health Interview Survey (NHIS), which inquired about smoking history and race/ethnicity, to analyze the demographic profiles of various high-risk smoking history categories. All statistical tests were two-sided., Results: The PLCO cohort included 18 114 former and 12 243 current LDCT-eligible smokers, plus 2283 20- to 29-pack-year current smokers. The hazard ratio for 20- to 29-pack-year current smokers compared with eligible (30+ pack-year) former smokers was 1.07 (95% confidence interval [CI] = 0.75 to 1.5). Based on the NHIS, 10 million persons in the United States are currently LDCT eligible; an additional 1.6 million (16%, 95% CI = 13.6% to 19.0%) are 20- to 29-pack-year current smokers. The percentage increase in eligibles if 20- to 29-pack-year current smokers were included was substantially greater for women than men (22.2%, 95% CI = 17.9% to 26.7%; vs 12.2%, 95% CI = 9.3% to 15.3%, P < .001) and for minorities than non-Hispanic whites (30.0%, 95% CI = 24.2% to 36.0%; vs 14.1%, 95% CI = 11.1% to 17.0%, P < .001)., Conclusion: The potential benefits and harms of recommending LDCT screening for 20 to 29-pack-year current smokers should be assessed., (Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.)