Prevention And Early Detection PDF

PREVENTATION AND EARLY DETECTION Smoking Cessation: Cigarette smoking is the leading preventable cause of mortality, causing over seven million deaths worldwide each year. Up to half of all regular smokers can be expected to die from a tobacco-related illness. Major caus...

PREVENTATION AND EARLY DETECTION Smoking Cessation: Cigarette smoking is the leading preventable cause of mortality, causing over seven million deaths worldwide each year. Up to half of all regular smokers can be expected to die from a tobacco-related illness. Major causes of smoking-related mortality include: o Atherosclerotic cardiovascular disease o Cancer o Chronic obstructive pulmonary disease (COPD) Cancers Associated with Smoking Tobacco: Carcinomas related to smoking include: o Colorectal o Cervical o Kidney o Larynx, pharynx, trachea, and bronchus o Lower urinary tract (including renal pelvis, ureter, and bladder) o Lung o Mesothelioma o Myeloid leukemia Reference: Vineis P, et al., "Tobacco and cancer: recent epidemiological evidence," Journal of the National Cancer Institute, 2004. Further reference: U.S. Centers for Disease Control and Prevention (CDC), Surgeon General’s Report, 2014. Lung Cancer Risk by Smoking Status: Smoking categories and associated hazard ratios for lung cancer risk: o Heavy smokers: Hazard ratio 1.00 o Reducers (heavy smokers who decreased smoking by ≥50%): Hazard ratio 0.73 o Light smokers (1-14 cigarettes per day): Hazard ratio 0.44 o Ex-smokers: Hazard ratio 0.17 o Never smokers: Hazard ratio 0.09 Source: Godtfredsen N, Prescott E, Osler M., "Effect of smoking reduction on lung cancer risk," JAMA, 2005. Edited By: Rathod, Ranjith  PREVENTATION AND EARLY DETECTION Impact of Quitting Smoking on Cancer Risk: Quitting smoking reduces risks for cancers of the lung, larynx, oral cavity and pharynx, esophagus, pancreas, bladder, stomach, colon and rectum, liver, cervix, kidney, and acute myeloid leukemia (AML). Risk reduction timeline after quitting: o Within 5-10 years, risk of mouth, throat, or voice box cancer is reduced by half. o Within 10 years, risk of bladder, esophagus, or kidney cancer decreases. o Within 10-15 years, lung cancer risk drops by half. o Within 20 years, risk for mouth, throat, voice box, or pancreatic cancer falls close to that of a non-smoker; cervical cancer risk also drops by about half. Physical Activity and Cancer Risk Reduction: Regular physical activity helps reduce the risk of several cancers, including: o Stomach o Colon o Endometrium Cancers Linked to Overweight and Obesity: 13 cancers are associated with overweight and obesity: o Meningioma (brain and spinal cord tissue cancer) o Thyroid cancer (risk modestly increases as BMI rises above 25 kg/m²) o Breast (postmenopausal women) o Adenocarcinoma of the esophagus o Multiple myeloma (cancer of blood cells) o Liver o Gallbladder o Kidneys o Uterus o Pancreas o Ovaries Cancer risk generally increases with higher BMI, with relative risks between 1.0 and 2.0. Diet and Cancer Prevention: Edited By: Rathod, Ranjith  PREVENTATION AND EARLY DETECTION Observational studies suggest dietary fiber may reduce the risk of colon polyps and invasive colon cancer, though this effect has not been confirmed in clinical trials. Sun Avoidance for Skin Cancer Prevention: Strategies to lower skin cancer risk include: o Reducing sun exposure o Wearing protective clothing o Adjusting outdoor activity patterns Sunscreens reduce actinic keratoses (a precursor to squamous cell cancer) but may not decrease melanoma risk as they prevent burning but could encourage prolonged sun exposure. Sunscreens may not block all wavelengths associated with melanoma risk. Cancer Chemoprevention: Aspirin: o A meta-analysis showed that 75 mg/day of aspirin reduced colorectal cancer incidence by 33% over 20 years, with no added benefit at higher doses. o The U.S. Preventive Services Task Force (USPSTF) recommends low-dose aspirin for colorectal cancer prevention in adults aged 50-59 with high cardiovascular risk. Tamoxifen and Raloxifene: o In a trial of over 13,000 high-risk women, tamoxifen reduced breast cancer risk by 49% over nearly 6 years, decreasing cases from 43.4 to 22 per 1,000 women. o The FDA has approved tamoxifen and raloxifene (for postmenopausal women only) to reduce breast cancer risk in women with a high 5-year risk (≥1.66% based on the Gail model). Finasteride in Prostate Cancer Prevention: o The Prostate Cancer Prevention Trial (PCPT) involved men aged 55+ randomized to finasteride or placebo with regular PSA screening and exams. o Finasteride reduced prostate cancer incidence from 24.4% to 18.4% over 7 years but increased high-grade (Gleason score >7) tumors from 6.4% to 9.1%. o Finasteride is not FDA-approved for prostate cancer prevention due to unresolved causation concerns. Vaccines for Cancer Prevention: Hepatitis B Vaccine: Edited By: Rathod, Ranjith  PREVENTATION AND EARLY DETECTION o Effective in preventing hepatitis and liver cancers due to chronic hepatitis B infection. HPV Vaccine: o The nonavalent vaccine (protecting against HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58) is available in the U.S. o Types 6 and 11 cause genital warts; types 16 and 18 are responsible for >70% of cervical cancers worldwide. o The vaccine prevents persistent HPV infections and preneoplastic lesions for those not previously infected. o It does not treat existing infections and is less effective for individuals previously exposed to these HPV strains. Surgical Interventions for Cancer Prevention: Cervical Dysplasia: o Treated with laser, loop electrosurgical excision, conization, or occasionally hysterectomy. Familial Polyposis and Ulcerative Colitis: o Colectomy can prevent colon cancer. Prophylactic Mastectomy: o Women with BRCA1 or BRCA2 mutations may choose bilateral mastectomy to prevent breast cancer. o Studies show a 90-94% reduction in breast cancer risk for those undergoing surgery, with a significant reduction in breast cancer-related deaths. Prophylactic Salpingo-Oophorectomy: o Used in high-risk women to reduce ovarian and breast cancer risk. o A study of BRCA mutation carriers found a 36% relative risk reduction for ovarian or primary peritoneal cancer and a 50% reduction in breast cancer risk, especially when performed before age 50. Breast Cancer Screening Recommendations by Age: Under 40: Routine screening mammography is not recommended due to low breast cancer incidence and lower test performance. Ages 40-49: Screening decisions are individualized based on patient preferences. Women may opt for screening if concerned about breast cancer risk, despite potential for false positives and overdiagnosis. Ages 50-74: Routine mammographic screening every 1-2 years is suggested. Edited By: Rathod, Ranjith  PREVENTATION AND EARLY DETECTION Ages 75+: Screening is recommended only if life expectancy is at least 10 years. Breast Cancer Screening Modalities: Mammography: Preferred for average-risk women, with a suggested interval of every 1-2 years. Ultrasound and MRI: Used for diagnostic evaluation of abnormal mammograms, not for routine screening in average-risk women. High-Risk Women: Screening may include MRI in addition to mammography, though the impact of supplemental MRI on mortality is unconfirmed. Cervical Cancer Screening by Age: Under 21: No screening recommended, regardless of sexual activity. Ages 21-29: Start screening at 21 with a Pap smear every 3 years (per USPSTF 2018 guidelines) or start at 25 with primary HPV testing every 5 years (per ACS 2020 guidelines). Ages 30-65: Screen with one of the following: o Primary HPV test every 5 years (FDA-approved test) o Co-testing (Pap + HPV) every 5 years o Pap test alone every 3 years. Over 65: Screening decisions depend on prior screening adequacy, life expectancy, and patient preferences. o If all prior results are normal, screening can discontinue after age 65, though some continue through age 74. o For inadequate or unknown prior screening, perform co-testing annually for 3 years, then every 5 years up to age 70 or beyond. High-Risk Patients: Screening frequency and cessation may differ for patients at increased risk, such as those with HIV or immunosuppression. Symptomatic Patients: Pap testing is recommended as part of the diagnostic workup, regardless of previous screening history. Abnormal Results: Abnormal Pap or HPV results require appropriate follow-up (e.g., colposcopy, excision) and long-term surveillance, as most do not return to routine screening. Edited By: Rathod, Ranjith  PREVENTATION AND EARLY DETECTION Colorectal Cancer Screening Methods: Colonoscopy: Recommended every 10 years for average-risk patients. Alternative Tests: o Fecal Immunochemical Test (FIT) annually. o Multitarget stool DNA (MT-sDNA) every 1-3 years. o CT colonography every 5 years. Other Tests: Sigmoidoscopy, sigmoidoscopy with FIT or gFOBT, and capsule colonoscopy. Colorectal Cancer Risk Assessment: Initial CRC risk assessment is done at the first visit and updated at least every five years. Screening recommendations may vary for patients with a family or personal history of CRC or advanced adenomatous polyps. Age to Start and Stop Screening: Initiate: Average-risk adults should start screening at age 45 (Grade 1A). Continue: Screening through age 75 for those with a life expectancy of 10+ years. Individualized decisions for ages 76-85. Screening up to age 86 may be reasonable if the patient was never screened. Enhanced Screening Indications: Family history should be assessed before age 40 and re-evaluated every 3-5 years, considering family size and paternity uncertainties. Screening Guidelines for High-Risk Familial Syndromes: Follow specific guideline intervals for colonoscopy. Family History of CRC or Advanced Adenoma/Serrated Lesions: o Start screening at age 40 or 10 years before the first-degree relative's diagnosis, whichever comes first. o Suggested interval: Colonoscopy every 5 years. o If colonoscopy is declined, offer annual FIT or MT-sDNA testing. Lung Cancer Screening for At-Risk Patients: Criteria: Adults aged 50-80 with a history of 20 pack-years of smoking, either current smokers or those who quit within the past 15 years. Edited By: Rathod, Ranjith  PREVENTATION AND EARLY DETECTION Method: Annual screening with low-dose helical CT (Grade 2B). Discontinuation: Stop screening if the individual has not smoked for 15 years or has limited life expectancy. Ovarian Cancer: Initial Assessment: Family history helps distinguish high-risk from average-risk women. Average-Risk Women: Screening for ovarian cancer is not recommended (Grade 1A) due to lack of mortality benefit and high rates of false positives with associated risks from invasive procedures. High-Risk Patients: Women with a family history, especially those with hereditary cancer syndromes (e.g., BRCA1, BRCA2, Lynch syndrome), should be referred for genetic counseling and testing. Risk-reducing bilateral salpingo-oophorectomy (rrBSO) may be considered for these patients. Prostate Cancer: Age to Begin Screening Discussion: o Average-Risk: Begin discussion at age 50. o High-Risk (e.g., Black men, those with a family history): Begin at age 40-45. o Genetic Mutations (e.g., BRCA1/2, Lynch syndrome): Consider starting as early as age 40. Screening Test: o PSA Testing: Recommended for prostate cancer screening, with an interval of 1-2 years. o Screening typically continues up to age 70, stopping earlier if life expectancy is under 10 years. Interpreting Abnormal PSA Results: o PSA >10 ng/mL: Direct referral to urology. o PSA 4-9.9 ng/mL: Retest in 6-8 weeks; if >4 ng/mL on repeat, refer to urology. o 5-Alpha Reductase Inhibitor (e.g., finasteride): Adjust PSA results accordingly; referral if PSA rises by >0.5 ng/mL. o Digital Rectal Examination (DRE): Not performed routinely in screening. If a DRE shows abnormalities, refer to urology regardless of PSA level. Edited By: Rathod, Ranjith