Cancer Screening: What You Need And When

A simplified guide based on the American Cancer Society (ACS) guidelines

Finding cancer early saves lives. But with so many recommendations out there, it’s easy to get lost. This guide breaks it down by cancer type, following the latest American Cancer Society (ACS) guidelines for adults at average risk.

⚠️ IMPORTANT: This guide is for average risk. If you have a strong family history, symptoms, or special conditions, talk to your doctor.

1. Breast Cancer (Mammogram)

The screening for breast cancer is a mammogram, which is a specialized X-ray of the breast tissue used to detect tumors that may be too small to feel.

1.1 When to start

• Ages 40-44: You can choose to start yearly mammograms if you want to.
• Age 45: Yearly mammograms are recommended for everyone at average risk.

1.2 From age 55 on

• Frequency: You may switch to a mammogram every 2 years, or keep going yearly if you prefer.
• Duration: Keep screening as long as you are in good health and expected to live at least 10 more years.

Note: Know how your breasts normally look and feel, and report any changes to your doctor immediately.

2. Colon Cancer (Colonoscopy and Other Tests)

Screening for colon cancer should begin at age 45 for people at average risk. There are several ways to get screened, and you should talk to your doctor about which is best for you.

2.1 Screening options

• Colonoscopy: Every 10 years. This is the most thorough test as it allows doctors to see the entire colon and remove polyps before they turn into cancer.
• FIT (Fecal Immunochemical Test): Every year. This test looks for hidden blood in the stool.
• FIT-DNA test (like Cologuard): Every 3 years.
• Flexible sigmoidoscopy: Every 5 years.

2.2 How long to keep screening

• Ages 50-75: Keep screening regularly.
• Ages 76-85: Talk to your doctor about whether it still makes sense for you based on your overall health.
• Over 85: Most people do not need it anymore.

3. Cervical Cancer (HPV Test and Pap Smear)

The ACS guideline puts the HPV test at the center of the recommendation because it detects the virus that causes almost all cervical cancers.

3.1 When to start

• Screening should begin at age 25.

3.2 Testing options

• HPV test (preferred): Every 5 years. The sample is collected by your doctor.
• HPV test (self-collection): Every 3 years. You collect your own vaginal sample.
• Co-test (HPV + Pap smear): Every 5 years.
• Pap smear alone: Every 3 years (only if an HPV test is not available).

3.3 Important details

• Get screened even if you have had the HPV vaccine.
• Get screened even if you are not currently sexually active.
• When to stop: At age 65, you can stop if you have had regular screenings and your recent results were normal. If you have had a total hysterectomy for non-cancer reasons, you no longer need screening.

3.4 HPV Vaccine — Prevention That Starts Early

The ACS recommends the HPV vaccine to prevent six types of cancer, including cervical, anal, and throat cancers.

• Ages 9-12: Routine vaccination for boys and girls (2 doses).
• Ages 13-26: Catch-up vaccination for those who missed it.
• Age 27+: Generally not recommended for adults in this age group.

4. Prostate Cancer (PSA and Digital Rectal Exam)

The main screening test is the PSA blood test. The digital rectal exam (DRE) may also be done as part of the screening process.

4.1 When to have the conversation

• Very high risk (age 40): For those with more than one first-degree relative (father or brother) with prostate cancer before age 65.
• High risk (age 45): For African Americans or those with one first-degree relative diagnosed before age 65.
• Average risk (age 50): Everyone else.

4.2 After screening

• If PSA is lower than 2.5 ng/mL: Repeat every 2 years.
• If PSA is 2.5 ng/mL or higher: Repeat every year.
• Men with a life expectancy under 10 years generally will not benefit from screening.

5. Lung Cancer (Low-Dose CT Scan)

Screening starts at **age 50** for those with a significant smoking history. It uses a low-dose CT scan (LDCT), which is a fast, non-invasive imaging test.

5.1 Who should get screened

Yearly screening is recommended for people who:

• Are 50 to 80 years old, AND
• Currently smoke OR quit less than 15 years ago, AND
• Have a smoking history of 20 pack-years or more.

“What’s a pack-year? It means smoking 1 pack a day for 20 years, or 2 packs a day for 10 years — any combination that adds up to 20.”

5.2 When to stop

• When you have not smoked for 15 years.
• If you develop a health problem that limits your life expectancy.
• At age 80.

Note: This post is for educational purposes and does not replace personalized medical advice.

Source: American Cancer Society. Cancer Screening Guidelines. 2025-2026.