Cancer Screening: Early Detection for Risk Reduction

• The World Health Organization (WHO) recommends appropriate cancer screening as part of preventive health care, even in people without symptoms, to help detect certain cancers at an early stage.
• Many cancers are more treatable when detected early, which can improve outcomes and, for some cancers, reduce the risk of dying from the disease.
• Genetic Testing for Cancer Risk is an option that can help identify people at high risk of developing cancer, particularly common cancers such as breast cancer, ovarian cancer, and colorectal cancer. 

Maintaining good health and preventing illness are important goals for everyone. Along with eating a balanced diet, exercising regularly, and getting enough sleep, routine health checkups play an important role in maintaining overall well-being. Regular checkups can help identify potential health problems and diseases at an early stage, when they may be easier to manage and treat. This is particularly important for serious conditions such as cancer, as early detection can improve treatment options and outcomes, and some cancers can be successfully treated when found at an early stage.

Genes are genetic material that determine many characteristics of the human body, including skin color, blood type, and height. Genetic abnormalities may also increase the risk of certain diseases, particularly cancer.

In general, approximately 90% to 95% of cancer risk factors are related to health, environmental factors, chemicals, and lifestyle behaviors. The remaining 5% to 10% are associated with inherited genetic factors that are present from birth. If these genetic risks can be identified early, people who carry cancer-related genes can receive support to help prevent the disease before symptoms develop.

With advances in medical technology, genetic testing for cancer risk can be performed before cancer fully develops, particularly in people at high risk, such as those who have several family members with cancer or relatives who developed cancer at a young age. Genetic testing for cancer risk can help assess an individual's tendency or potential risk of developing cancer.

Today, genetic testing can assess the risk of several types of cancer, particularly cancers that are common and have a clear hereditary component, including breast cancer, ovarian cancer, and colorectal cancer.

Who should consider genetic testing for cancer risk?
People who may consider genetic testing for cancer risk include:

• People who are concerned about their risk of cancer and want to understand their risk. 
• People who have more than two first-degree relatives with cancer, or one first-degree relative who developed cancer before the age of 50. 
• People who have a family member with hereditary cancer. 

Genetic testing for inherited cancer risk can be performed using a blood sample or a cheek swab. The results are interpreted by a doctor or genetic counselor, who can explain what they mean and recommend appropriate follow-up based on the findings.

Negative result: No clinically significant inherited genetic variant associated with an increased cancer risk was identified. However, a negative result does not eliminate the possibility of developing cancer, as most cancers result from a combination of genetic, environmental, and lifestyle factors. Maintaining a healthy lifestyle and following age- and risk-appropriate cancer screening recommendations remain important.

Positive result: An inherited genetic variant associated with an increased risk of certain cancers was identified. This does not mean that cancer will definitely develop. Your doctor or genetic counselor can assess your individual risk and recommend a personalized plan, which may include more frequent or earlier cancer screening, preventive measures, and, when appropriate, referral to specialists.

Regular health checkups and appropriate cancer screening are important parts of preventive health care. Screening aims to detect certain cancers—or precancerous changes—at an early stage, often before symptoms develop, when treatment may be more effective.

Cancer screening is particularly important for people at increased risk, such as those with a strong family history of cancer or other recognized risk factors. Many cancers can be treated successfully when detected early, and screening for certain cancers has been shown to reduce the risk of dying from the disease.

Following recommended screening guidelines based on age, sex, personal and family history, and other risk factors can help support early detection and better health outcomes.

Regular health checkups and appropriate cancer screening are important parts of preventive health care. Screening aims to detect certain cancers—or precancerous changes—at an early stage, often before symptoms develop, when treatment may be more effective.

Cancer screening is particularly important for people at increased risk, such as those with a strong family history of cancer or other recognized risk factors. Many cancers can be treated successfully when detected early, and screening for certain cancers has been shown to reduce the risk of dying from the disease.

Following recommended screening guidelines based on age, sex, personal and family history, and other risk factors can help support early detection and better health outcomes.

The cancer screening methods include:

• Breast cancer screening 
  Mammography is the standard screening test for breast cancer and can help detect cancer early, when treatment is more likely to be successful. Women at average risk are generally advised to begin regular mammography at age 40. Women at higher risk, including those with harmful BRCA1 or BRCA2 variants, may benefit from additional screening with breast MRI. A doctor can recommend an appropriate screening plan based on individual risk factors.
• Cervical cancer screening
  Testing for Human papillomavirus (HPV) using an HPV DNA Test and a Pap test are screening methods for cervical cancer that can help prevent the disease by detecting abnormal cells and allowing them to be treated before they develop into cancer.
  The World Health Organization recommends that women aged 21 to 65 undergo cervical cancer screening every 3 to 5 years to reduce disease severity and the risk of death. The American Cancer Society also recommends routine screening for women in the appropriate age range, even if they have received the HPV vaccine, as vaccination does not protect against all cancer-causing HPV types.
• Prostate cancer screening
  The American Cancer Society recommends prostate cancer screening for men aged 45 and older, particularly those with a family history of prostate cancer. Screening may include a blood test for Prostate-Specific Antigen (PSA) and a Digital Rectal Examination (DRE).
• Colorectal cancer screening
  The American Cancer Society recommends that adults at average risk begin regular colorectal cancer screening at age 45. Screening options include colonoscopy, flexible sigmoidoscopy, CT colonography, and stool-based tests. The recommended interval varies depending on the test—for example, every 5-10 years for colonoscopy and annually for stool test. Regular screening can help detect colorectal cancer early and identify precancerous polyps that can be removed before they develop into cancer, helping reduce the risk of dying from the disease. Screening is generally recommended through age 75 for people in good health, while decisions about screening from ages 76 to 85 should be individualized based on overall health, life expectancy, previous screening history, and personal preferences.
• Lung cancer screening
  The American Cancer Society recommends annual lung cancer screening with low-dose computed tomography (LDCT) for adults aged 50 to 80 who currently smoke or have smoked in the past and have a smoking history of at least 20 pack-years. 
  Annual LDCT screening can help detect lung cancer at an earlier, more treatable stage and has been shown to reduce the risk of dying from lung cancer in people at high risk. 
• Liver cancer screening
  For people at increased risk of hepatocellular carcinoma (HCC), liver ultrasound every 6 months is recommended for surveillance. Alpha-fetoprotein (AFP) may also be used alongside ultrasound to improve detection. However, AFP levels can be elevated for reasons other than liver cancer, and a normal AFP level does not rule out HCC. 
  Chronic hepatitis C can increase the risk of liver cancer, particularly in people who have developed cirrhosis. Hepatitis C screening can help identify people who have been exposed to HCV. An anti-HCV antibody test is used for initial screening, and a positive result should be followed by an HCV RNA test to determine whether there is an active infection. 
• Ovarian cancer screening
  Combination of a transvaginal ultrasound and the tumor markers CA 12-5 and HE4 in the blood, can be used to detect ovarian cancer at an early stage, particularly in women at high risk. These tests can also be used to help diagnose ovarian cancer in people who have symptoms and to assess whether the cancer has returned. 
  

Early cancer detection aims to identify cancer at an early stage, often before it causes noticeable symptoms. Detecting cancer early can expand treatment options and, for many cancers, improve the chances of successful treatment and survival. However, not all cancers can be detected through routine health checkups, so screening should be based on age, sex, personal and family history, and individual risk factors.

Early cancer detection may include the following:

• Medical history: This includes daily lifestyle, family history, environmental factors, smoking, alcohol consumption, and symptoms such as bloating, loss of appetite, unexplained weight loss, chronic cough, and changes in bowel habits. 
• Physical examination: This may include examinations of the skin, head, breasts, abdomen, genital organs, rectum, and lower part of the colon. 
• Laboratory tests: These can help with diagnosis, treatment, and monitoring of treatment outcomes, including: 
  • Blood tests 
  • Urine and stool tests 
  • Blood biochemistry tests 
  • X-rays 
  • Nuclear medicine tests 
  • Histopathological examination (examination of tissue under a microscope) 

For people at increased risk of certain cancers, genetic testing can help identify inherited genetic variants associated with a higher risk of developing cancer. Genetic counseling can help interpret the results and guide appropriate screening and preventive care.

A multidisciplinary team of specialists can then develop an individualized care plan, from risk assessment and early detection to diagnosis, treatment, and follow-up, providing comprehensive care tailored to each patient.