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Ambulatory Care - Cancer Screening - Fast Facts | NEJM Resident 360

Screening for cancer has been controversial, and recommendations have evolved over time. In addition, cancer-screening guidelines from professional specialty societies, advocacy organizations, and the U.S. Preventive Services Task Force (USPSTF) often conflict with one another. In this section, we focus on recommendations from the USPSTF, but it is worthwhile to be familiar with other groups’ recommendations that often receive media attention and are known to patients. Recognize that screening is not without risks. False-positive results can lead to unnecessary tests and procedures that cause physical and emotional harm. Ultimately, the decision to screen is a personalized one after discussing the risks and benefits with the patient. In this section, we summarize screening recommendations for the following cancers:

• Colorectal Cancer

• Cervical Cancer

• Breast Cancer

• Lung Cancer

• Prostate Cancer

The Electronic Preventive Services Selector (ePSS) app is an easy-to-use tool that allows you to search by patient age, sex, and other information to look up individualized recommendations from the USPSTF for asymptomatic patients at average risk. Patients typically need to have a life expectancy of at least 10 more years to benefit from screening.

Colorectal Cancer

The 2021 USPSTF guideline on screening for colorectal cancer recommendations are as follows:

Patients at Average Risk

• All patients should be screened for colorectal cancer between ages 45 and 49 years (grade B recommendation) and ages 50 and 75 years (grade A recommendation).

• Screening between ages 76 and 85 should be individualized and based on each patient’s overall health (grade C recommendation). Patients in this age group who have never been screened are more likely to benefit. They should be healthy enough to undergo treatment for colorectal cancer and should not have comorbid conditions that significantly limit life expectancy.

• The following screening methods are acceptable in average-risk individuals, although the estimated benefit varies. Consider patient preference; it is better to screen with a method that the patient prefers than not to screen at all.

  • stool-based

    • annual high-sensitivity fecal occult-blood test (FOBT): has randomized controlled trial (RCT) evidence of mortality benefit

    • annual fecal immunochemical test (FIT): improved accuracy over FOBT

    • FIT-DNA test every 1 or 3 years: less specific than FIT but more sensitive

  • direct visualization

    • CT colonography every 5 years: no sedation but still requires bowel prep

    • flexible sigmoidoscopy every 5 years: RCT evidence of mortality benefit

    • flexible sigmoidoscopy plus annual FIT every 10 years

    • colonoscopy every 10 years: prospective cohort evidence of mortality benefit

Prevention: The USPSTF recommends initiating low-dose aspirin use for the primary prevention of cardiovascular disease (CVD) and colorectal cancer in adults aged 50 to 59 years who have a 10% or greater 10-year CVD risk, are not at increased risk for bleeding, have a life expectancy of at least 10 years, and are willing to take low-dose aspirin daily for at least 10 years. The mechanism may be related to aspirin’s inhibition of cyclooxygenase-2 activity, which normally stimulates oncogenesis pathways downstream (see NEJM article, editorial, and NEJM Journal Watch summary).

Patients at Higher Risk

The USPSTF did not examine evidence regarding patients with a positive family history, but guidelines are available from the U.S. Multi-Society Task Force (MSTF) on Colorectal Cancer (see table below).

• A strong family history, such as a first-degree relative who had colorectal cancer before age 50, should prompt consideration for referral to a specialist with expertise in hereditary syndromes, such as familial adenomatous polyposis or hereditary nonpolyposis colorectal cancer (Lynch syndrome).

• Although multiple options for screening exist, the MSTF recommends colonoscopy in patients with increased risk for colorectal cancer, when possible.

• Once an adenoma is detected, the patient should initiate scheduled surveillance.

MSTF Recommendations for Persons with High-Risk Family Histories Not Associated with Polyp Syndromes

Cervical Cancer

The 2018 USPSTF cervical cancer screening guideline recommends:

• Screening in women aged 21–65 with cytology (Pap smear) every 3 years and women aged 30–65 with combination cytology and human papillomavirus (HPV) co-testing or high-risk HPV testing alone every 5 years (grade A recommendation)

The USPSTF recommends against:

• screening with HPV testing alone or with cytology in women aged <30

• screening women aged <21

• screening women aged >65 who have had adequate prior screening (three consecutive negative cytology results or two consecutive negative HPV results within 10 years with most recent test in the past 5 years)

• screening women who have had a hysterectomy with removal of the cervix and who do not have a history of a high-grade precancerous lesion (cervical intraepithelial neoplasia [CIN] grade 2 or 3) or cervical cancer

The recommendations do not apply to women who have received a diagnosis of a high-grade precancerous cervical lesion or cervical cancer, women with in utero exposure to diethylstilbestrol, or women who are immunocompromised, such as with HIV.

Breast Cancer

The 2016 USPSTF breast cancer screening guideline recommends:

• Biennial screening mammography for women aged 50–74 (grade B). This recommendation is controversial and varies by specialty group.

• For women aged 40–49, the decision to start screening mammography is individualized on the basis of patient risks and values; patients who place a higher value on the benefits may choose biennial screening (grade C).

• Current evidence is insufficient to recommend screening mammography at age ≥75.

• Although there is no recommendation for breast self-examination screening, patients should be encouraged to inform physicians of any concerning breast masses, skin changes, or nipple discharge.

Note: The 2019 USPSTF guideline on medication use to reduce risk of breast cancer is a grade B recommendation for prescribing selective estrogen-receptor modulators such as tamoxifen or raloxifene to prevent breast cancer in women at increased risk after discussing the risks and benefits. The Breast Cancer Risk Assessment Tool is one available method to help estimate risk.

Lung Cancer

The USPSTF lung cancer screening guideline was updated in 2021. The final recommendation statement expands the age range for screening and reduces pack-year history. The following are grade B recommendations:

• lung cancer screening with low-dose computed tomography (CT) every year for all adults aged 50 to 80 years who have a 20-pack-year smoking history and either currently smoke or have quit within the past 15 years

• discontinue screening if a patient has not smoked for 15 years or has developed a health issue that limits life expectancy or the ability/willingness to have curative lung surgery

Prostate Cancer

The 2018 USPSTF prostate cancer screening guideline recommends:

• Informed discussion with men aged 55–69 about the potential harms and benefits of periodic prostate-specific antigen (PSA)–based screening (grade C); the USPSTF’s infographic to help clinicians counsel patients and estimate risks and benefits explains that for every 1000 men aged 55–69 offered screening, over 10–15 years, one to two deaths can be avoided while 60 or more men may experience serious complications, such as urinary incontinence and/or sexual impotence, from treatment. 

• PSA-based screening is not recommended for men aged ≥70.

• African-Americans and men with a family history of prostate cancer are at increased risk, but the USPSTF is unable to make any specific recommendations for these populations

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