{"entity":{"id":"chemoprevention","kind":"technology","name":"Chemoprevention & risk-reducing surgery","aka":[],"tldr":"Drugs or surgery for people at high inherited risk, before any cancer appears.","summary":"Tamoxifen/raloxifene/anastrozole halve breast cancer incidence in high-risk women (uptake is low). Aspirin reduces colorectal cancer in Lynch syndrome (CAPP2). Risk-reducing mastectomy and salpingo-oophorectomy in BRCA carriers; opportunistic salpingectomy for the general population. Prophylactic gastrectomy in CDH1 carriers.","status":"standard-of-care","asOf":"2026-09-04","wikipedia":"https://en.wikipedia.org/wiki/Chemoprophylaxis","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Chemoprophylaxis"},{"label":"British Association of Dermatologists and BSSCII: skin cancer advice for organ transplant recipients, patient information leaflet (June 2024)","url":"https://www.skinhealthinfo.org.uk/condition/skin-cancer-in-organ-transplant-recipients/"},{"label":"British Association of Dermatologists: squamous cell carcinomas, patient information leaflet (updated April 2022; the leaflet gives its own next review date as April 2025 and no newer version exists at this address or at bad.org.uk)","url":"https://www.skinhealthinfo.org.uk/condition/squamous-cell-carcinomas/"}],"tags":[],"related":["cure-paths"],"cancers":["tnbc","breast-hr-positive","ovarian","colorectal","gastric","skin-cancer","basal-cell-carcinoma","cutaneous-scc"],"sections":["prevention"],"technologies":[],"targets":["brca","estrogen-receptor"],"drugs":[],"companies":["cancer-prevention-pharmaceuticals","scirouter"],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":["cancer-prevention-research","european-journal-of-cancer-prevention"],"dependsOn":[],"notes":["Keratinocyte skin cancer, what is offered in the UK and to whom. The British Association of Dermatologists says in its squamous cell carcinoma leaflet that there is some evidence nicotinamide taken by mouth may reduce the formation of actinic keratoses, and that treating areas of scaly sun damage may reduce the risk of a squamous cell carcinoma. Its transplant leaflet is more specific: where a person has had multiple skin cancers, medicines may be added for prevention, naming acitretin and nicotinamide, and reducing or changing the immunosuppression itself is discussed between the dermatologist and the transplant physicians."],"principle":"Remove the at-risk tissue or block the hormonal/inflammatory driver of carcinogenesis.","strengths":["Large absolute risk reduction in carriers"],"limitations":["Side effects deter uptake; surgery is irreversible"]},"route":"/technologies/chemoprevention/","neighbours":{"roadmap":[{"id":"prevention-roadmap","kind":"roadmap","name":"Cancer prevention roadmap: tobacco control and vaccines → biomarker-guided chemoprevention → interception in carriers","route":"/roadmaps/prevention-roadmap/"},{"id":"cure-paths","kind":"roadmap","name":"Paths to cures: interception, eradication, control","route":"/roadmaps/cure-paths/"}],"cancer":[{"id":"basal-cell-carcinoma","kind":"cancer","name":"Basal cell carcinoma","route":"/cancers/basal-cell-carcinoma/"},{"id":"colorectal","kind":"cancer","name":"Colorectal cancer","route":"/cancers/colorectal/"},{"id":"cutaneous-scc","kind":"cancer","name":"Cutaneous squamous cell carcinoma","route":"/cancers/cutaneous-scc/"},{"id":"early-gastric-cancer","kind":"cancer","name":"Early gastric cancer","route":"/cancers/early-gastric-cancer/"},{"id":"gastric","kind":"cancer","name":"Gastric & gastro-oesophageal junction cancer","route":"/cancers/gastric/"},{"id":"breast-hr-positive","kind":"cancer","name":"HR-positive / HER2-negative breast cancer","route":"/cancers/breast-hr-positive/"},{"id":"lynch-associated-colorectal-cancer","kind":"cancer","name":"Lynch syndrome-associated colorectal cancer","route":"/cancers/lynch-associated-colorectal-cancer/"},{"id":"msi-high-colorectal","kind":"cancer","name":"Mismatch-repair deficient (MSI-high) colorectal cancer","route":"/cancers/msi-high-colorectal/"},{"id":"ovarian","kind":"cancer","name":"Ovarian cancer","route":"/cancers/ovarian/"},{"id":"skin-cancer","kind":"cancer","name":"Skin cancer (all types)","route":"/cancers/skin-cancer/"},{"id":"tnbc","kind":"cancer","name":"Triple-negative breast cancer (TNBC)","route":"/cancers/tnbc/"}],"section":[{"id":"prevention","kind":"section","name":"Prevention & Risk","route":"/fronts/prevention/"}],"target":[{"id":"brca","kind":"target","name":"BRCA1 / BRCA2 (HRD)","route":"/targets/brca/"},{"id":"estrogen-receptor","kind":"target","name":"Estrogen receptor (ERα)","route":"/targets/estrogen-receptor/"}],"company":[{"id":"cancer-prevention-pharmaceuticals","kind":"company","name":"Cancer Prevention Pharmaceuticals","route":"/companies/cancer-prevention-pharmaceuticals/"},{"id":"nouscom","kind":"company","name":"Nouscom","route":"/companies/nouscom/"},{"id":"nsabp-foundation","kind":"company","name":"NSABP Foundation","route":"/companies/nsabp-foundation/"},{"id":"scirouter","kind":"company","name":"SciRouter","route":"/companies/scirouter/"}],"journal":[{"id":"cancer-prevention-research","kind":"journal","name":"Cancer prevention research","route":"/journals/cancer-prevention-research/"},{"id":"european-journal-of-cancer-prevention","kind":"journal","name":"European journal of cancer prevention","route":"/journals/european-journal-of-cancer-prevention/"}],"drug":[{"id":"acitretin","kind":"drug","name":"Acitretin","route":"/drugs/acitretin/"},{"id":"imiquimod","kind":"drug","name":"Imiquimod","route":"/drugs/imiquimod/"},{"id":"nicotinamide","kind":"drug","name":"Nicotinamide","route":"/drugs/nicotinamide/"},{"id":"raloxifene","kind":"drug","name":"Raloxifene","route":"/drugs/raloxifene/"},{"id":"tamoxifen","kind":"drug","name":"Tamoxifen","route":"/drugs/tamoxifen/"}],"term":[{"id":"ageing-tissue-field-theory","kind":"term","name":"Ageing tissue and clonal fields: cancer as a disease of old tissue","route":"/terms/ageing-tissue-field-theory/"},{"id":"barretts-esophagus","kind":"term","name":"Barrett's oesophagus","route":"/terms/barretts-esophagus/"},{"id":"chemoprevention-and-er-negative-breast-cancer","kind":"term","name":"Chemoprevention (tamoxifen, anastrozole, raloxifene) and ER-negative breast cancer","route":"/terms/chemoprevention-and-er-negative-breast-cancer/"},{"id":"tumor-promoting-inflammation","kind":"term","name":"Enabling characteristic: tumour-promoting inflammation","route":"/terms/tumor-promoting-inflammation/"},{"id":"lynch-syndrome","kind":"term","name":"Lynch syndrome","route":"/terms/lynch-syndrome/"},{"id":"microenvironment-inflammation-theory","kind":"term","name":"Microenvironment and inflammation: tumours as wounds that do not heal","route":"/terms/microenvironment-inflammation-theory/"},{"id":"risk-factor","kind":"term","name":"Risk factor","route":"/terms/risk-factor/"},{"id":"skin-cancer-after-organ-transplant","kind":"term","name":"Skin cancer after an organ transplant","route":"/terms/skin-cancer-after-organ-transplant/"},{"id":"sun-protection-after-skin-cancer","kind":"term","name":"Sun protection after a skin cancer diagnosis","route":"/terms/sun-protection-after-skin-cancer/"}],"technology":[{"id":"alcohol-reduction-labelling","kind":"technology","name":"Alcohol reduction, pricing and cancer warning labels","route":"/technologies/alcohol-reduction-labelling/"},{"id":"aspirin-cancer-prevention","kind":"technology","name":"Aspirin for cancer prevention and adjuvant therapy","route":"/technologies/aspirin-cancer-prevention/"},{"id":"bariatric-surgery-cancer-incidence","kind":"technology","name":"Bariatric surgery and cancer incidence","route":"/technologies/bariatric-surgery-cancer-incidence/"},{"id":"interception-vaccination","kind":"technology","name":"Cancer interception vaccines","route":"/technologies/interception-vaccination/"},{"id":"glp1-agonists-cancer-risk","kind":"technology","name":"GLP-1 receptor agonists and obesity-related cancer risk","route":"/technologies/glp1-agonists-cancer-risk/"},{"id":"risk-reducing-salpingectomy","kind":"technology","name":"Risk-reducing and opportunistic salpingectomy","route":"/technologies/risk-reducing-salpingectomy/"},{"id":"drug-repurposing","kind":"technology","name":"Systematic drug repurposing","route":"/technologies/drug-repurposing/"},{"id":"vitamin-d-omega3-supplementation","kind":"technology","name":"Vitamin D and omega-3 supplementation","route":"/technologies/vitamin-d-omega3-supplementation/"}],"trial":[{"id":"aspree","kind":"trial","name":"ASPREE (ASPirin in Reducing Events in the Elderly)","route":"/trials/aspree/"},{"id":"kerala-oral-screening","kind":"trial","name":"Kerala oral cancer visual screening trial (Trivandrum)","route":"/trials/kerala-oral-screening/"},{"id":"tumorapa","kind":"trial","name":"TUMORAPA (switching from a calcineurin inhibitor to sirolimus after a transplant skin cancer)","route":"/trials/tumorapa/"},{"id":"vital","kind":"trial","name":"VITAL (VITamin D and OmegA-3 TriaL)","route":"/trials/vital/"}],"pathway":[{"id":"field-cancerisation","kind":"pathway","name":"Field cancerisation","route":"/pathways/field-cancerisation/"},{"id":"inflammation-nfkb","kind":"pathway","name":"Inflammation & NF-κB","route":"/pathways/inflammation-nfkb/"},{"id":"wnt","kind":"pathway","name":"Wnt / β-catenin","route":"/pathways/wnt/"}],"idea":[{"id":"idea-prev-brca1-denosumab-prevention","kind":"idea","name":"A bone drug to prevent breast cancer in BRCA1 carriers","route":"/ideas/idea-prev-brca1-denosumab-prevention/"},{"id":"idea-fund-prevention-moonshot","kind":"idea","name":"A delivery-science moonshot for prevention we already own","route":"/ideas/idea-fund-prevention-moonshot/"},{"id":"idea-prev-glp1-cancer-prevention-rct","kind":"idea","name":"A trial of GLP-1 weight-loss drugs with cancer as the primary outcome","route":"/ideas/idea-prev-glp1-cancer-prevention-rct/"},{"id":"idea-moon-population-interception","kind":"idea","name":"A whole-population cancer interception programme: risk-stratify every adult, detect and intercept early","route":"/ideas/idea-moon-population-interception/"},{"id":"idea-interception-vaccines","kind":"idea","name":"Cancer interception vaccines for high-risk carriers","route":"/ideas/idea-interception-vaccines/"},{"id":"idea-prev-lynch-aspirin-implementation","kind":"idea","name":"Get every Lynch syndrome carrier onto the right dose of aspirin","route":"/ideas/idea-prev-lynch-aspirin-implementation/"},{"id":"idea-prev-glp1-endometrial-hyperplasia","kind":"idea","name":"GLP-1 drugs to reverse endometrial precancer in women with obesity","route":"/ideas/idea-prev-glp1-endometrial-hyperplasia/"},{"id":"idea-field-interception","kind":"idea","name":"Intercept cancer at the field stage","route":"/ideas/idea-field-interception/"},{"id":"idea-prev-low-dose-tamoxifen-uptake","kind":"idea","name":"Low-dose tamoxifen for high-risk women, prescribed by pharmacists and nurses","route":"/ideas/idea-prev-low-dose-tamoxifen-uptake/"},{"id":"idea-prev-chemoprevention-master-protocol","kind":"idea","name":"One master trial for cancer prevention drugs across many precancers","route":"/ideas/idea-prev-chemoprevention-master-protocol/"},{"id":"idea-moon-population-germline-screening","kind":"idea","name":"Population germline screening for hereditary cancer genes with cascade testing","route":"/ideas/idea-moon-population-germline-screening/"},{"id":"idea-prev-precursor-endpoints-for-approval","kind":"idea","name":"Regulators accept shrinking of precancer as the endpoint for prevention drug approval","route":"/ideas/idea-prev-precursor-endpoints-for-approval/"}],"person":[{"id":"angelina-jolie","kind":"person","name":"Angelina Jolie","route":"/people/angelina-jolie/"},{"id":"bernard-fisher","kind":"person","name":"Bernard Fisher","route":"/people/bernard-fisher/"},{"id":"weiderpass-elisabete","kind":"person","name":"Elisabete Weiderpass","route":"/people/weiderpass-elisabete/"},{"id":"jack-cuzick","kind":"person","name":"Jack Cuzick","route":"/people/jack-cuzick/"},{"id":"judy-garber","kind":"person","name":"Judy E. Garber","route":"/people/judy-garber/"},{"id":"chaturvedi-pankaj","kind":"person","name":"Pankaj Chaturvedi","route":"/people/chaturvedi-pankaj/"},{"id":"vincent-tuohy","kind":"person","name":"Vincent K. Tuohy","route":"/people/vincent-tuohy/"}],"bottleneck":[{"id":"b-hereditary-risk","kind":"bottleneck","name":"Inherited risk is mostly unidentified","route":"/bottlenecks/b-hereditary-risk/"},{"id":"b-generic-repurposing","kind":"bottleneck","name":"No incentive to repurpose cheap drugs","route":"/bottlenecks/b-generic-repurposing/"},{"id":"b-prevention-adoption","kind":"bottleneck","name":"Prevention we already have is not deployed","route":"/bottlenecks/b-prevention-adoption/"}],"paper":[{"id":"paper-capp2-aspirin-lynch-lancet-2020","kind":"paper","name":"CAPP2: two years of aspirin cuts bowel cancer in Lynch syndrome by more than a third over 10 years","route":"/key-papers/paper-capp2-aspirin-lynch-lancet-2020/"},{"id":"paper-sankaranarayanan-oral-screening-lancet-2005","kind":"paper","name":"Effect of screening on oral cancer mortality in Kerala, India","route":"/key-papers/paper-sankaranarayanan-oral-screening-lancet-2005/"},{"id":"paper-ibis-i-tamoxifen-lancet-oncol-2015","kind":"paper","name":"IBIS-I: five years of tamoxifen keeps preventing breast cancer for at least 20 years","route":"/key-papers/paper-ibis-i-tamoxifen-lancet-oncol-2015/"}],"institution":[{"id":"icmr-nicpr","kind":"institution","name":"ICMR-National Institute of Cancer Prevention and Research","route":"/institutions/icmr-nicpr/"},{"id":"musc-hollings","kind":"institution","name":"MUSC Hollings Cancer Center","route":"/institutions/musc-hollings/"},{"id":"arizona-cancer-center","kind":"institution","name":"University of Arizona Cancer Center","route":"/institutions/arizona-cancer-center/"}]}}