CANCER: FROM BEGINNING TO END
From the 50th Annual Scientific Assembly of the American Academy of Family Physicians, October 3-6, 2007, Chicago, IL
| ADVANCES IN CANCER SCREENING AND CARE —Richard C. Wender, MD, Alumni Professor and Chair, Department of Family and Community Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA |
| Incidence: in May 2002, American Cancer Society (ACS) approved goal of 50% reduction in age-adjusted cancer mortality by 2015 (compared to mortality peak, which occurred in 1990); midpoint report revealed ≈1% annual decline in cancer mortality from 1990 to 2002; translates to 315,000 cancer deaths prevented (≈1.9 million deaths prevented by 2015); on track to be halfway to 2015 goal; dramatic declines in lung cancer, colorectal cancer, and prostate cancer deaths in men; plateau in lung cancer deaths among women; breast cancer deaths “another great success story”; colon cancer deaths in women declining since 1950s (reason unknown); cervical cancer deaths also declining; reasons for decline—reduction in smoking, particularly in men, due to policy change and counseling by primary care providers; improvement in early detection of breast cancer (due to mammography) and in treatment; screening and colonoscopy (colon cancer); prostate cancer detection and treatment; improved therapy; dramatic progress made in types of cancer amenable to screening and prevention but little progress in other types |
| War on cancer: 6 elements for “defeating” cancer—cancer health care agenda driven by public health considerations; public health analysis of research investment; emphasis on primary care; expanded access to primary and cancer care services; institution of systems of care to replace individual physician as sole pilot of care; payment mechanisms to support systems; why primary care important—more primary care associated with better health outcomes, lower cost, and greater equity in health care; associated with earlier detection of breast, cervical, melanoma, and colon cancers (virtually any cancer); role of physicians—includes 1) risk assessment, 2) prevention counseling and intervention, 3) screening, 4) diagnosis of symptomatic patients, 5) assembling of treatment team, 6) support and coordination of care, 7) long-term follow-up, and 8) end-of-life counseling and care; most important fundamental tool in risk assessment taking family history; family history—determines age at which to initiate screening, as well as mode of screening for colon and breast cancer; provides clues for high-risk families (eg, BRCA1, BRCA2, hereditary nonpolyposis colon cancer); has some impact on general cancer risk; in speaker’s audit of 500 charts, 55% reported family history of cancer, but age at diagnosis of family member not recorded (younger relatives mean higher risk); few charts mention presence of family history of polyps (higher risk); only 35% updated family history |
| Prevention: fighting tobacco— remains most important measure; success mainly due to policy change; speaker believes tobacco use should be fifth vital sign in outpatient setting; need system that routinely identifies and intervenes with tobacco users as often as possible; intervention based on stage of readiness; advise patient to start thinking about quitting (stage-based approach); counseling works, but more intense treatment better; current guidelines state pharmacologic intervention recommended for all smokers, except pregnant women; many tools available for smoking cessation, including computer programs; refer patients to your state’s “quitline” (toll-free telephone number that provides access to national network of smoking cessation support); obesity—other important risk factor; no evidence that eating fruits and vegetables important determinant of risk in prospective studies; strongly associated with cancer risk (26 types of cancer); next public health challenge; however, unlike tobacco, no guidelines; need change in policy to have impact |
| Screening: principal determinant of whether patient screened for cancer whether primary care physician recommended it; principal determinant for physician whether patient had preventive health visit; all organizations that issue guidelines attempting to be evidence-based; guidelines not just function of evidence but also of values |
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Prostate cancer: in 1992, ACS recommended annual screening for all men 50 yr of age (guideline too far ahead of evidence, causing backlash); in 1997, ACS updated guideline to encourage shared decision-making; United States Preventive Services Task Force (USPSTF) indicates that guidelines for prostate-specific antigen (PSA) screening essentially same for almost every organization; PSA first reported as valuable screening tool in 1991 and approved as early detection test in 1994; dramatic shifts seen in every aspect of prostate cancer; current estimate <1% of all prostate cancer diagnosed in advanced stage; 5-yr survival if diagnosed early, 100% (33% if distant disease); in pre-PSA era, 5- yr survival 75% (presently, survival 99.8%); epidemiologist (Jamal) found association between higher screening rates and decrease in late-stage disease and mortality; trial—695 men with early prostate cancer randomized to radical prostatectomy or watchful waiting; followed for 8 yr; statistically significant mortality benefit seen in group randomly assigned to radical prostatectomy; radical prostatectomy group had higher rate of erectile dysfunction and urinary leakage, while watchful waiting group had higher rate of obstructive urinary symptoms; study—retrospective; published in JAMA (44,000 men diagnosed with localized prostate cancer; 32,000 treated and 12,000 observed; significant survival advantage with hazard ratio <1 associated with treatment in every subgroup (even older men with low-risk disease); myth that prostate cancer in older men different disease; older men less likely to die of prostate cancer because more likely to die of something else in interim; if older man lives long enough, just as likely as younger man to die of prostate cancer; screening associated with detection at earlier stage and therefore lower mortality; accordingly, prostate cancer mortality declining rapidly in screened populations; aggressive treatment more effective than watchful waiting; definitive evidence from randomized trials lacking |
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Colon cancer: real issue reaching population; options include fecal occult blood test annually and flexible sigmoidoscopy every 5 yr; frustrating to speaker that many primary care clinicians and obstetricians/gynecologists rely on digital rectal examination (DRE) with guaiac test in office (proven ineffective; not approved screening option); colonoscopy every 10 yr; double-contrast barium enema no longer performed as screening test; no clearly superior screening test; new guidelines forthcoming; structural imaging tests (eg, computed tomography [CT] colonography, barium enema, flexible sigmoidoscopy, colonoscopy) principally target polyps; stool testing strategies principally target early cancers; value of removing every polyp unknown, but has significant cost and capacity issues (necessary to rescreen patient more frequently and increases risk for perforation); stool testing detects polyps (most common finding from abnormal stool blood test, leading to colonoscopy); sensitivity for polyps higher for colonoscopy and probably CT; study from University of Wisconsin compared colonoscopy to CT colonography and found CT better (7 perforations in colonoscopy group); for screening test to be considered option, must have sensitivity of 50%; new screening options include DNA test in stool and CT colonography (virtual colonoscopy) |
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Breast cancer: most organizations recommended mammography every 1 to 2 yr for women in their 40s (somewhat controversial); no controversy for women in 50s; in April 2007, American College of Physicians recommended that mammography be offered with risk communication and shared decision-making for women in their 40s and should no longer be routinely done; speaker’s opinion that women in their 40s should be routinely screened (despite lack of perfect evidence) |
| Diagnosis: one of toughest challenges in primary care; look for persistent or worsening symptoms and track these patients; any persistent symptom possible sign of cancer; delay in diagnosis of breast cancer most common reason for successful lawsuits against primary care physicians; diagnostic test for palpable breast mass is biopsy (not mammography or ultrasonography [US]); diagnostic test for positive stool blood test is colonoscopy (not another stool blood test) |
| Role of primary care in treatment: assembly of treatment team; “rate cancer more than facility,” ie, type and/or stage of cancer dictates facility used (eg, if cancer rare or second or third recurrence, encourage patient to see cancer treatment center for second opinion); role in active treatment variable; possible role in options counseling, symptom management, and management of comorbidities |
| Survivorship: specific guidelines for follow-up of survivors of childhood cancers (looking at, eg, height, body mass index, facial and dental growth, infertility in girls, heart failure in some cases); monitor thyroid function in those who received radiotherapy to neck; high risk for breast cancer in those who received radiotherapy to chest; new guideline that women who had irradiation to breast for treatment of lymphoma or who have BRCA1 or BRCA2 mutation should be screened with annual magnetic resonance imaging (MRI) of breast; in adults—new paradigm of cancer as chronic disease; estimated that by 2030, 18.5 million cancer survivors (presently 10.6 million); similarity to chronic diseases—long-lasting (residual disease, even in cured patients); affects quality of life, costs, health care utilization, and morbidity and mortality; can be disabling; shares other important features with heart disease and diabetes (eg, lifestyle, genetics, environmental impact); precursor conditions (eg, colon polyps, cervical dysplasia, ductal carcinoma in situ [DCIS]); generally speaking, earlier diagnosis contributes to superior outcomes (shown for almost every form of solid tumor); difference from other chronic diseases—insurance companies starting to put limits on treatment; curable; cost structure different |
| Cancer and end of life: need to help patients deal with end of life; earlier referral to hospice results in better quality of life; key questions to determine best time to stop treating advanced disease still unknown; death from cancer, accompanied by adequate symptom control, may be preferable to death from other causes (eg, Alzheimer’s disease); if managed well, can be enriching family experience; choosing to receive palliative care alone, without active treatment, not admitting defeat; death from cancer not failure; family physicians on front line in war against cancer |
| ISSUES IN CANCER SCREENING —Alfred O. Berg, MD, MPH, Immediate past Chair, United States Preventive Services Task Force, and Professor and Chair, Department of Family Medicine, University of Washington School of Medicine, Seattle |
| Screening program: start with group of asymptomatic patients, screen them, detect preclinical condition, treat, and improve outcome; ideally, should have good randomized trials showing that screening program improves outcomes; effective screening program—improves prognosis, requires less radical treatment, reassures patients that results negative, and saves money; potential harms—hazards intrinsic to test, labeling effects, adverse effects of unnecessary treatment, and false-positive or false-negative results leading to anxiety, follow-up tests, and false reassurance (in cases of false- negative results); poorly constructed screening program can divert resources; counseling interventions—purpose to change behavior and improve outcome; good link between changing behavior and improving outcome; challenge is in counseling aspect, where evidence weak that primary care providers can persuade patients to effectively change behavior; recommendation codes A to I—based on quality of evidence and net benefit; A recommendation has good evidence with benefits substantially outweighing harms; B recommendation has at least fair evidence; C category has good to fair evidence, but benefit and harm closely balanced; D category has evidence pointing to ineffectiveness or harm; I category has insufficient evidence; new category of inactive recommendations includes those no longer clinically relevant, those that cannot be implemented, or those that have low public health burden or that are otherwise determined out of scope |
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Breast cancer: B recommendation that mammography be performed in women between 40 and 69 yr of age every 1 to 2 yr; I conclusion (insufficient evidence) for clinical breast examination and breast self-examination (BSE); rationale that only fair evidence found for reducing breast cancer mortality, with evidence strongest in older age group (beginning at age 50 yr) and absolute benefit of mammography smaller; question as to whether benefit in younger age group artifact of study; benefits of mammography increase and harms decrease with age; evidence probably generalizable to women >70 yr of age; insufficient evidence to specify screening interval; decisions based on 8 high-quality trials; found 2% to 32% reduction in breast cancer mortality; meta-analysis of 8 trials conducted, and regardless of how trials combined, relative risk reduction 20% to 30%; 5 trials show benefit in younger women, with similar relative risk reduction (because breast cancer less common in younger age group, absolute benefit smaller); number needed to screen to prevent one breast cancer death in women 40 to 49 yr of age, ≈1500; confidence interval, 650 to 6000; in older age group, number needed to screen, ≈800; no randomized clinical trial on clinical breast examination (CBE) alone, so impossible to determine whether it adds value to mammography; 3 good-quality trials on BSE; largest and best trial (done in China) showed that it caused harm (anxiety, unnecessary biopsy and follow-up); no evidence of reduction in all- cause mortality; potential harms—from follow-up testing necessary with many false-positive results; enduring anxiety experienced by patients; potential for overdiagnosis of DCIS; theoretic harm of radiation exposure; Task Force conclusions—women should be informed of potential benefits and harms, beginning at 40 yr of age and should understand limitations of test in their age group; assist woman in determining her preferences and values, but let woman decide (document her decision) |
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Prostate cancer: analytic framework similar; evidence— good that screening detects early-stage prostate cancer; whether early detection improves outcomes, inconclusive (evidence mixed); screening and treatment associated with important harms; benefits of treating early prostate cancer (compared with harms) unknown; I recommendation (ie, insufficient evidence to recommend for or against routine screening) to use PSA or DRE; screening also associated with important harms, including frequent false-positive results, unnecessary anxiety and biopsies, and potential complications of treatment of some cancers that may never have affected patient’s health; insufficient evidence to determine whether benefits outweigh harms for screened population; informed consent recommended if decision made to screen men 50 to 70 yr of age in good health; screening black men likely beneficial; PSA recommended for screening; DRE has no real value; screening annually too frequent; benefits include reassurance from negative test and possibly avoiding death due to prostate cancer; harms include false-positive tests, labeling, anxiety of receiving diagnosis, and treatment-associated erectile dysfunction, incontinence, and bowel dysfunction (20%-80% of patients) |
Suggested Reading
Berg AO; U.S. Preventive Services Task Force: Chemoprevention of breast cancer: recommendations and rationale. Am J Nurs 103:107, 109, 111, 113, 2003; Burack RC: Life expectancy and colorectal cancer screening. Ann Intern Med 146:758; author reply 758, 2007; Freedland SJ: Obesity and prostate cancer: importance of race and stage of disease. J Urol 178:1842, 2007; Gemignani ML: Breast cancer screening for women 40 to 49 years of age: what is a clinician to do? Obstet Gynecol 110:548, 2007; Haylock PJ et al: The cancer survivor's prescription for living. Am J Nurs 107:58, 2007; Kiberd B: Colon cancer screening. CMAJ 174:975; author reply 975, 2006; Potter MB: Counseling women about mammography: benefits vs. harms. Am Fam Physician 76:652, 2007; Rockey DC: Colon cancer screening, polyp size, and CT colonography: making sense of it all? Gastroenterology 131:2006, 2006; Roy HK et al: Colon cancer screening: the good, the bad, and the ugly. Arch Intern Med 166:2177, 2006; Sardanelli F et al: Management of an inherited predisposition to breast cancer. N Engl J Med 357:1663; author reply 1663, 2007; Schwartz LM et al: Participation in mammography screening. BMJ 335:731, 2007; Sharifi N et al: Screening for prostate cancer: current status and future prospects. Am J Med 120:743, 2007; Thompson IM et al: Prostate-specific antigen in the early detection of prostate cancer. CMAJ 176:1853, 2007; White HK et al: The older cancer patient. Med Clin North Am 90:967, 2006.
Educational Objectives
| The goal of this program is to improve early detection of cancer through appropriate cancer screening. After hearing and assimilating this program, the clinician will be better able to: |
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1. Recognize the role of primary care physicians in screening and management of cancer. |
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2. Demonstrate the importance of obtaining a family history in screening for cancer. |
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3. Select the appropriate screening tests for breast, colon, and rectal cancer. |
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4. Summarize the recommendations of the United States Preventive Services Task Force for breast and prostate cancer screening and the level of evidence supporting it. |
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5. Discuss the potential harms of cancer screening tests. |
Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and planning committee members to disclose relevant financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business or commercial interest. For this program, the faculty and planning committee reported nothing to disclose.
Acknowledgments
Drs. Wender and Berg were recorded at the 50th Annual Scientific Assembly of the American Academy of Family Physicians, held October 3-6, 2007, in Chicago, IL. The Audio-Digest Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.
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