Cancer Screening Guide: What Tests to Get and When to Start

Introduction

Have you ever wondered: "What tests can I take regularly to prevent cancer, or at least catch it early enough to improve outcomes?"

The answer is yes — cancer screening can help detect tumors early or monitor treatment effectiveness. But with so many types of cancer and individual differences, which tests should you get, when should you start, and how often should you be screened?

This comprehensive guide provides evidence-based answers.

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What Is Cancer Screening?

Cancer screening refers to targeted examinations performed on asymptomatic individuals to detect tumors at an early stage.

Important principles:

• Not all cancers are suitable for screening
• Different tests serve different purposes (detection vs. monitoring treatment)
• More tests are not necessarily better
• The best approach is to spend time and money where it matters most

The ideal cancer screening plan should be developed at a professional health screening center, based on your individual risk factors, risk stratification, and personal preferences.

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Screening Timing Varies by Individual

While cancer incidence increases with age, age is not the only determining factor. Cancer development is related to genetics, age, diet and lifestyle habits, and environmental factors. Because of these variables, the optimal time to begin screening and screening frequency differ from person to person.

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Breast Cancer

General Risk Population

Moderate to High Risk Population

Ages 30–75: Annual mammography or breast MRI recommended.

For patients with family history, begin screening 10 years before the youngest age of diagnosis in the family, but no earlier than age 25.

High-risk factors include:

• Carrying breast cancer susceptibility genes (e.g., BRCA1/2)
• First-degree relatives with breast cancer history
• Personal history of breast cancer
• History of chest radiation therapy
• Diagnosed before age 40 with atypical ductal hyperplasia, atypical lobular hyperplasia, or lobular carcinoma in situ

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Cervical Cancer

Screening Recommendations

• Begin cervical cancer screening at age 21
• Women under 30: Cervical cytology (Pap smear) or high-risk HPV testing at least every 1–3 years
• Women 30 and older: Cervical cytology plus high-risk HPV testing at least every 2–3 years

When to Stop Screening

Women over 65 may consider stopping if:

• 3 consecutive normal Pap smears in the past 10 years, OR
• 2 consecutive normal Pap + HPV co-tests
• Most recent test within the past 5 years
• No history of moderate or higher-grade precancerous lesions

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Prostate Cancer

General Risk Population

• Begin at age 50: PSA (Prostate-Specific Antigen) testing every 2 years
• At age 60: If PSA < 1 ng/mL, decide whether to continue based on personal preference and life expectancy

High Risk Population

• Begin at age 40: If PSA > 1 μg/L or carrying BRCA2 gene — PSA testing every 2 years
• Begin at age 45: Men with family history of prostate cancer — PSA testing every 2 years

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Lung Cancer

Screening Recommendation

Ages 50–80 with high-risk factors: Low-dose CT scan every 1–2 years

High-Risk Factors

1. Smoking history: ≥20 pack-years (packs per day × years smoked), or passive smoking ≥20 years. If quit, less than 15 years since cessation
2. Occupational exposure: Long-term contact with radon, arsenic, beryllium, chromium compounds, asbestos, chloromethyl ether, silica, coke oven emissions, or coal soot
3. Family history: First or second-degree relatives with lung cancer, combined with ≥15 pack-years smoking or ≥15 years passive smoking
4. Regional factors: Living in high-incidence areas
5. Medical history: Prior cancer history or pulmonary diseases (COPD or pulmonary fibrosis)

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Liver Cancer

Screening Recommendation

High-risk populations should undergo abdominal ultrasound and AFP (Alpha-Fetoprotein) testing every 6 months:

• Asian males over 40
• Asian females over 50

High-Risk Factors

• Active hepatitis (elevated transaminases and/or high viral load)
• Family history of liver cancer
• Liver cirrhosis

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Colorectal Cancer

General Risk Population (Starting at Age 50)

High Risk Population

Begin at age 40, or 10 years before the age at which a relative was diagnosed.

High-risk factors include:

• First-degree relatives with colorectal cancer
• First-degree relatives with adenomatous polyps or familial adenomatous polyposis
• Personal history of intestinal adenomas
• Long-standing (8–10 years) inflammatory bowel disease
• Recurrent positive fecal occult blood without identifiable cause

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Gastric Cancer

Screening Recommendation

Starting at age 45, individuals with any of the following risk factors should undergo gastroscopy every 3 years:

1. Living in or from high-incidence regions (certain areas in China, Japan, Korea, Venezuela, Chile)
2. Helicobacter pylori infection
3. History of chronic atrophic gastritis, gastric ulcers, gastric polyps, post-surgical remnant stomach, hypertrophic gastritis, or pernicious anemia
4. First-degree relatives with gastric cancer
5. Other high-risk factors: high-salt diet, preserved/pickled foods, smoking, heavy alcohol consumption

Note: Japan and Korea recommend starting gastric cancer screening from age 40.

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Summary

The recommendations above are general guidelines based on age and risk stratification. Individual circumstances vary significantly. If you're unsure about your personal risk level or screening plan, we strongly recommend consulting with a physician to develop a customized screening schedule.