in the same relative.
The possibility of heredity cancer is one reason why health screening questionnaires contain questions about cancer (and other illnesses) affecting extended family members.
Genetic Testing. If a person meets any of the criteria indicating they may have a heightened risk for developing cancer, an option they might wish to consider is genetic testing. Choosing to undergo genetic testing is a personal decision made for various reasons, but best made in collaboration with others, including other family members, one's physician, and a genetic counselor.
Currently, consideration of genetic testing is recommended in the following cases:
A personal or family history suggests a genetic cause of cancer.
A test will yield clear results regarding changes in a specific gene or genes.
The results will help with the diagnosis or management of a condition. This might guide someone at higher risk to counteract it with such steps as surgery, medication, frequent screening, or lifestyle changes.
Genetic counselors are very instrumental both in deciding whether or not to undergo genetic testing, as well as conferring with about the test findings. The counselor can explain the pros and cons of genetic testing, help people cope with the process of completing the testing, and give advice regarding ways to lower cancer risk in the future.
1.10 Cancer Screening and Diagnosis
Screening tests to aid physicians in the detection and diagnosis of cancer fall into one of four general types. Doctors conduct a physical examination to check for signs of any health abnormalities or indicators of disease, such as external lumps or localized pain. A thorough physical exam includes a review of the patient's family history of the disease, health history, and lifestyle factors, all of which may contribute to the development of cancer [15–36].
Laboratory tests, both routine and specialized, consist of an analysis of samples of tissue, blood, urine, or other bodily substances, to check for the presence of certain chemicals, abnormal cells, etc. A variety of imaging procedures are also available to give physicians a look at organs, bones, and other internal body structures. As mentioned earlier, genetic testing can provide information about specific gene mutations (changes) associated with certain types of cancer.
Before undergoing any screening tests, it is important to know the risks involved with the tests themselves, as some cancer screening tests pose more risk than the potential benefit. It should be ascertained whether the screening has actually been proven to reduce the chance of dying from cancer. Bleeding or other problems can result from certain types of screening procedures. For example, screening for colon cancer with sigmoidoscopy or colonoscopy can cause tears in the lining of the colon, leading to internal bleeding.
In addition, cancer screening test results may be abnormal even though there is no cancer present, which is called a false‐positive test result. A false‐positive result causes patient anxiety and usually follow‐up with more tests and procedures, which may have additional risks. On the other hand, test results sometimes indicate no cancer even though the disease is present. A person who receives a false‐negative test result may delay seeking medical care even if there are other abnormal symptoms.
Many screening tests have been shown to detect cancer at an early, more treatable stage and thereby reduce the risk of dying from this disease. The following is a list of a few types of cancer frequently encountered in modern societies, along with tests used to screen for them:
1.10.1 Colon Cancer
Colonoscopy, sigmoidoscopy, and high‐sensitivity fecal occult blood tests (FOBTs) have all been proven to decrease deaths from colorectal cancer. Colonoscopy and sigmoidoscopy also help prevent colorectal cancer because they detect abnormal colonic growths (polyps), which can be removed at that time before they develop into cancer. In addition, there are screenings for colon cancer in low‐risk patients using a stool sample, offering an alternative to the risks associated with, and the preparation for, a colonoscopy.
Virtual colonoscopy, also called CT colonography or computed tomography, is an imaging procedure in which a radiologist uses X‐rays and a computer to create images of the rectum and colon from outside the body. Ulcers, polyps, and cancer can be detected using this test.
1.10.2 Lung Cancer
Low‐dose helical computed tomography has been shown to decrease lung cancer deaths among heavy smokers aged 55–74 years.
1.10.3 Breast/Cervical/Ovarian/Endometrial Cancers
Mammography screening produces an X‐ray image of breast tissue and has been shown to significantly reduce mortality from breast cancer among women aged 40–74, especially those aged 50 or older.
In addition to mammography, physicians recommend all adult women obtain regular clinical breast examinations and perform breast self‐examinations at home, checking for unusual lumps or thicknesses in the breast tissue, or any other unusual breast symptoms. These physical exams have also been proven to reduce breast cancer mortality rates.
Regarding the possible presence of cervical cancer, Pap tests (or Pap smears) and human papillomavirus (HPV) testing decrease the risk of cancer by identifying and treating abnormalities in cells before they become cancerous. Overall, these tests have resulted in decreased deaths from cervical cancer. Testing is generally recommended starting at the age of 21 and continued at regular intervals until a female reaches 65 years, at which time they can be curtailed if recent results have been normal.
For females who have been identified as carrying a harmful mutation in the BRCA1 or BRCA2 gene, indicating an increased risk for breast and other types of cancer, physicians may recommend magnetic resonance imaging (MRI) of their breasts.
Mutations in BRCA1 or BRCA2 genes also predispose females to ovarian or endometrial cancer, and in cases where these mutations are evidenced, a transvaginal ultrasound is utilized to obtain an image of females' ovaries and/or uterus. The CA‐125 blood test is sometimes used alongside a transvaginal ultrasound for early detection of ovarian cancer, particularly in those having an increased risk of developing this disease. CA‐125 is a cancer antigen, which can be elevated in the presence of ovarian cancer. Furthermore, evidence of someone having an inherited cancer syndrome called Lynch syndrome makes them predisposed to endometrial cancer in particular, along with several other specific cancers.
1.10.4 Prostate Cancer
For early detection of prostate cancer, physicians perform a digital rectal exam and a blood test called a prostate‐specific antigen (PSA) test. PSA is a chemical produced by the prostate gland, and elevated levels of it in the blood may indicate the presence of prostate cancer, although not definitely.
1.10.5 Liver Cancer
In people with increased risk for liver disease, doctors may suggest an ultrasound of the liver and possibly an alpha‐fetoprotein (AFP) blood test. AFP is a protein produced by the liver, and an elevated level of it in the blood can indicate the presence of liver cancer.
1.10.6
