The American College of Physicians (ACP) update of their standing guidance statement for colorectal-cancer screening in asymptomatic average-risk adults was recently published to assist clinicians ...with implementing evidence-based patient care. After assessing existing guideline literature, the ACP recommended five actions: consider not screening adults ages 45 to 49 years; stop screening adults older than 75 years; discuss benefits, harms, costs, availability, frequency, and patient values/preferences with patients prior to choosing a screening method; and when choosing, recommend biennial rather than annual use of a fecal immunochemical test or a guaiac fecal occult blood test and avoid recommending computed tomography colonography or stool DNA tests. While the ACP guidelines are rigorous, well-intended, and considerate of patients' input, their greatest impact may result from highlighting the need for researchers to help frontline clinicians to describe the risk, costs, and benefits/harms of various colorectal-cancer screening strategies in an effective, yet time-efficient, manner given the all-too-brief annual patient encounters. In the United States, reimbursement is still dependent on U.S. Preventive Services Task Force recommendations which are somewhat more liberal in contrast to the ACP's approach which strongly favors randomized, controlled trial evidence to guide the delivery of prevention and screening services to asymptomatic average-risk patients.
Various clinical and epidemiologic studies show that nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin and cyclooxygenase inhibitors (COXIBs) help prevent cancer. Since eicosanoid ...metabolism is the main inhibitory targets of these drugs the resulting molecular and biological impact is generally accepted. As our knowledge base and technology progress we are learning that additional targets may be involved. This review attempts to summarize these new developments in the field.
E-cigarettes have the ability to deliver nicotine in a manner that is similar to, and, theoretically, safer than, combusted tobacco. However, these devices are extremely heterogeneous and regulation ...has struggled to keep up with their rapid evolution. A compilation of early data suggest that e-cigarettes may contain numerous toxic substances, including known carcinogens. However, there are few data available on the short- and long-term health effects of e-cigarettes, including any potential effect on cancer risk. Until more is known, e-cigarettes should not be considered a safe alternative to combusted tobacco use.
After more than a century, aspirin remains one of the most commonly used drugs in western medicine. Although mainly used for its anti-thrombotic, anti-pyretic, and analgesic properties, a multitude ...of clinical studies have provided convincing evidence that regular, low-dose aspirin use dramatically lowers the risk of cancer. These observations coincide with recent studies showing a functional relationship between platelets and tumors, suggesting that aspirin’s chemopreventive properties may result, in part, from direct modulation of platelet biology and biochemistry. Here, we present a review of the biochemistry and pharmacology of aspirin with particular emphasis on its cyclooxygenase-dependent and cyclooxygenase-independent effects in platelets. We also correlate the results of proteomic-based studies of aspirin acetylation in eukaryotic cells with recent developments in platelet proteomics to identify non-cyclooxygenase targets of aspirin-mediated acetylation in platelets that may play a role in its chemopreventive mechanism.
Nearly all cancers have identifiable histologically defined precursors known as precancers. These precancers offer a window of opportunity to intercept the neoplastic process to prevent its ...development into invasive cancer. However, lack of knowledge regarding the evolution of precancers and the microenvironmental pressures shaping them precludes efforts to intercept them. Technological developments over the past decade have facilitated the study of precancers at a previously unattainable resolution. Calls for a national PreCancer Atlas effort incorporating these technologies were heeded in 2018, with the launch of the Human Tumor Atlas Network (HTAN) as part of the Beau Biden National Cancer Moonshot. Since then, five funded HTAN groups have focused their efforts on profiling precancers from breast, colon, skin, and lung. In this time, what progress has been made? What is next for HTAN and the field of premalignant biology? And are there lessons that individual investigators and the larger prevention field can learn from this initial effort to accelerate the development of novel early detection methods, risk prediction biomarkers, and interception agents? A special collection of invited reviews by experts in cancer evolution, systems biology, immunology, cancer genetics, preventive agent development, among other areas, attempts to answer these questions.
Minimally invasive molecular biomarkers have been applied to the early detection of multiple cancers in large scale case‐control and cohort studies. These demonstrations of feasibility herald the ...potential for permanent transformation of current cancer screening paradigms. This commentary discusses the major opportunities and challenges facing the preclinical development and clinical validation of multicancer early detection test strategies. From a diverse set of early detection research perspectives, the authors recommend specific approaches and highlight important questions for future investigation.
Minimally invasive, molecular biomarkers demonstrate feasibility for the early detection of multiple cancers in large‐scale case control and cohort studies. Here the paradigm‐changing opportunities and the challenges facing the preclinical development and clinical validation of multicancer early‐detection test strategies are discussed.
The rich, multidisciplinary history of cancer prevention recounted here begins with surgical and workplace recommendations of the 1700s and ends with 2009 results of the enormous (35,535 men) ...Selenium and Vitamin E prostate Cancer Prevention Trial (SELECT). This history comprises a fascinating array of chemopreventive, vaccine, surgical, and behavioral science research, both preclinical and clinical. Preclinical milestones of cancer prevention include the 1913 and 1916 mouse studies by Lathrop and Loeb of cancer development associated with pregnancy or cancer prevention through castration (oophorectomy), preventing chemically induced mouse carcinogenesis as early as 1929, energy restriction studies in the 1940s, the 1950s discoveries and later molecular characterizations of field cancerization and multistep carcinogenesis, and the effects of angiogenesis inhibition in genetically engineered mice reported in 2009. The extraordinary panoply of clinical research includes numerous large and smaller chemoprevention studies of nutritional supplements, other dietary approaches, a Bacillus Calmette-Guérin trial in 1976, molecular-targeted agents, and agents to prevent infection-related cancers such as hepatitis B virus vaccine to prevent liver cancer in 1984. Clinical surgical prevention includes removal of intraepithelial neoplasia detected by screening (including Pap testing developed in 1929 and culposcopy for cervical premalignancy and colonoscopy and polypectomy to prevent colorectal cancer begun in the 1960s) and prophylactic surgeries, such as in Lynch syndrome patients begun in 1977. Behavioral studies include smoking cessation and control beginning in the 1950s, obesity control rooted in studies of 1841, and genetic-counseling and cancer-survivorship studies. This history of pioneering events may help in better understanding who we are and what we want to achieve as cancer prevention researchers and practitioners.
Coxibs, including celecoxib, and other nonsteroidal anti-inflammatory drugs (NSAID), including aspirin, are among the most promising cancer chemopreventive agents in development today. This article ...examines the data on the efficacy of these agents in animal model studies of cancer prevention carried out by the authors. The studies evaluated here are restricted to our rodent models of colon/intestinal, bladder, and nonmelanoma skin cancer, in which celecoxib and other NSAIDs were administered as either cancer preventive or therapeutic agents. These studies may shed light on several questions. Is celecoxib unique compared with other NSAIDs, and if so, what implications would this have for human use? Are standard NSAIDs (which inhibit both COX-1 and COX-2) as effective as celecoxib in animal studies? Is the efficacy of celecoxib in particular or NSAIDs in general due to their off-target effects or to their effects on COX-1 and COX-2? What is the likely efficacy of low-dose aspirin? Some questions raised by human trials and epidemiology are discussed and related to our observations in animal model studies. We also discuss the problem of cardiovascular (CV) events associated with coxibs and certain other NSAIDs and whether results in animal models are predictive of efficacy in humans. On the basis of epidemiologic studies and its CV profile, aspirin seems to be the most promising NSAID for preventing human colorectal, bladder, and skin cancer, although the animal data for aspirin are less clear. A comprehensive understanding of the results of coxibs and other NSAIDs in animal studies may help inform and shape human trials of these commonly employed, relatively inexpensive, and highly effective compounds.
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