1.
A 40-year-old female with hypertension presents to your office for a routine examination. She has no new complaints today. Her blood pressure is well controlled with hydrochlorothiazide. During your examination, you counsel her on the need to consider screening for breast cancer with a mammogram. The patient asks, in addition, if you will screen her for ovarian and gastric cancer as she had two friends who died of these illnesses. You review her family history, which is unremarkable except for breast cancer in a great aunt diagnosed at age 78. You explain that screening for cancer is evidence based, includes both benefi ts and potential harms, and is not done for every type of cancer. Which of the following are principles that should guide the creation of guidelines?
Correct Answer
D. Both A and C.
Explanation
Key Concept/Objective: To recognize that guidelines are established by expert panels charged with using available evidence to create explicit recommendations that are easy to follow in clinical practice
To avoid errors in judging the evidence and weighing benefi ts and harms, expert panels, as well as individual clinicians, should do the following: (1) use an independent systematic review to distinguish assertions based on evidence from those based on other grounds, (2) make the rationale for a recommendation explicit, and (3) be free from fi nancial and political confl icts of interest. Although the use of these measures does not guarantee a correct decision, they represent the best safeguards against bias. The USPSTF assigns an overall grade to each prevention service that refl ects the overall strength of evidence and the magnitude of benefit.
2.
A 50-year-old male with paraplegia secondary to a motor vehicle accident is in your offi ce to establish care after recently moving to the area. He has no new health complaints. He gets around easily on his wheelchair and is remarkably fi t as an ongoing downhill skier in the Para-Olympics. After a thorough review of systems and a physical examination, you bring up age-appropriate cancer screening.Which of the following cancer screenings for men holds a United States Preventive Services Task Force (UPSTF) grade A (strongest recommendation)?
Correct Answer
C. Colon cancer screening through fecal occult cards
Explanation
Key Concept/Objective: To recognize that only two cancer screenings contain a grade A recommendation from the USPSTF, colon cancer screening and cervical cancer screening
Only two cancer screening tests meet the USPSTF criteria for a strong recommendation: (1) Papanicolaou (Pap) smears for cervical cancer and (2) fecal occult blood testing or endoscopic procedures for colorectal cancer. With both of these conditions, the aim of screening is to remove precancerous lesions, which prevents invasive cancer, saves the involved organ, and reduces disease-specifi c mortality. By contrast, the more controversial cancer screening tests, such as PSA and mammography, detect invasive cancers and lead to aggressive treatments (prostatectomy and mastectomy) that often destroy the involved organ and that have more substantial
morbidity than cone biopsy for cervical cancer and polypectomy for colorectal cancer.
3.
A 55-year-old female returns to your offi ce to review her screening mammogram fi ndings. Six previous yearly mammograms have been unremarkable; however, her most recent mammogram shows an area of concern in her right breast. Further testing was recommended by the radiologist. The patient has no new complaints today. She has noticed no new lumps, skin changes, or nipple discharge from her breasts. Her family history is unremarkable for breast or ovarian cancer. In discussing the results with your patient, she becomes tearful and asks, “Does this mean I have cancer?”Which of the following regarding screening for breast cancer is true?
Correct Answer
A. Women who get 10 annual mammograms have about a 50% chance of having a false positive result.
Explanation
Key Concept/Objective: To understand that in breast cancer screening, false positives are common and to recall that there is no proven all-cause mortality benefi t to screening
In the trials, which involved nearly half a million women, mammography clearly had no effect on all-cause mortality. The USPSTF, although fully aware of this fact, chose to base their assessment of the benefi ts on the narrower grounds of breast cancer mortality. They chose to let women decide for themselves whether reducing the risk of dying of breast cancer was important to them. Judging from the trials, about 1,200 women 40 to 70 years of age must be invited to be screened four to fi ve times over 10 years to prevent one death from breast cancer. Of women 40 to 49 years of age, 1,792 (95% confi dence interval 764 to 10,540) must be invited to be screened to prevent one death from breast cancer. Women who get 10 annual mammograms have about a 50% chance that at least one of them is a false positive result; many of these false positive results necessitate a biopsy.
4.
A 76-year-old male with atrial fi brillation, coronary artery disease, and hypertension presents for a followup visit. He has no new complaints today except for a need for medication refi lls. Review of systems is relatively unremarkable; his angina remains stable, occurring only very rarely with heavy physical exertion. Physical examination reveals an irregularly irregular heart rhythm and trace pedal edema. After addressing his medical problems, you ask the patient to have his lipids and thyroid-stimulating hormone checked. The patient asks if his blood work should also include his “yearly prostate test.”Which of the following regarding the USPSTF recommendations on prostate cancer screening is true?
Correct Answer
D. Screening in men age > 75 years is not recommended.
Explanation
Key Concept/Objective: To realize the confl icting information regarding prostate cancer screening in men < 75 and to understand that screening for men > 75 is not recommended
The USPSTF concluded that evidence was insuffi cient to recommend for or against prostate cancer screening in men younger than 75 years; the USPSTF recommends against screening for prostate cancer in men age 75 years or older. This conclusion was based on the following considerations: (1) there are no completed randomized, controlled trials of screening, although studies are ongoing in the United States and in Europe; (2) although prostate cancer is a major cause of cancer death in men, many cases are clinically indolent (in autopsy studies, the prevalence of histologic prostate cancer in men older than 50 years is about 30%, but only 3% of men die of prostate cancer); (3) the value of treatment for the localized cancers targeted by screening is unknown; the one randomized, controlled trial of radical prostatectomy, which found no improvement in the 15-year survival rates of patients undergoing surgery, has been criticized for methodological problems (another randomized, controlled trial comparing expectant management with radical prostatectomy for the treatment of localized cancer is under way); (4) aggressive treatments for localized disease are associated with signifi cant morbidity; and (5) mortality from prostate cancer has not declined in the United States despite 15 years of widespread use of PSA testing.
5.
A 62-year-old male with a history of depression presents to your offi ce for follow-up. His depression has been improving on medications and weekly visits with a psychologist. Review of his chart reveals that he has had a recent colonoscopy with no abnormalities; he has elected to forego prostate cancer screening. The patient, who recently returned from visiting family in another country, asks about pancreatic cancer screening.Which of the following statements regarding USPSTF pancreatic cancer screening guidelines is true?
Correct Answer
B. Screening is not recommended.
Explanation
Key Concept/Objective: To recognize that not all cancers have available screening tests, usually due to uncertain benefit and to the morbidity of diagnosis and treatment
The USPSTF recommended against screening for bladder, ovarian, pancreatic, and testicular cancers. In each case, the deciding factor was that screening and treatment caused serious, immediate harms, whereas evidence of a benefi t was inconclusive. As with mammography for breast cancer, screening for these cancers is aimed at detection of early invasive disease, and treatment has substantial morbidity. This degree of morbidity is in contrast to that associated with screening for colonic polyps or cervical dysplasia,for which treatment is relatively safe and is aimed at preserving, rather than removing, the involved organ.