Fundamentals of Cancer Detection, Treatment, and Prevention. Surya K. De

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 Skin Cancer

People who are at risk for skin cancer, and those who live in climates with sunshine much of the year, are advised to examine their skin regularly or have this done by a health care provider. Prompt reporting of skin changes, such as a new mole or change in the appearance of a preexisting mole, can lead to early detection of skin cancer.

1.11 Cancer Treatment Options

      Currently, there are many kinds of cancer treatments available, depending on the type of cancer and how advanced it is. Some cancer patients only require one type of treatment, whereas others may need more than one – including surgery, chemotherapy, medication, or radiation therapy – provided in a variety of specific combinations and timings [37–82].

      1.11.1 Surgery

      It is the physical removal of cancer from the body. In some cases, this may be a simple outpatient procedure, requiring an hour or two in a specialist's office. In other cases, it may involve a major operation with a few nights in the hospital and intense therapy treatments afterward.

      “Clear margins” is a term well known for its association with cancer surgery. When the cancerous tissue is taken out, it is ideal to have a “clear margin” (clear of cancerous matter) surrounding the affected area targeted during the surgery. Depending on the location of the cancer, specific measurements are used to define “clear” in this regard. Basically, since cancer cells may have been in contact with tissues around them, surgeons take a section of healthy tissue around the cancerous parts in order to be certain all of the cancer has been removed.

      Preparation for cancer surgery varies depending on the procedure. The surgeon's office contacts patients well in advance to go over special instructions, not only for what to do beforehand, but also for what to expect on the day of surgery and during recovery afterward. Many large hospitals even provide cancer patients access to local networks offering counseling, housing, and other services for patients and their relatives during treatments.

      1.11.2 Radiation Therapy

      It is another modality of cancer treatment during which high‐intensity radiation is used to kill cancer cells and shrink tumors [48,49]. Depending on several factors, such as the location of cancer, and the age and health of the patient, radiation can be an effective therapy. It is often used in conjunction with other treatment methods, e.g. reducing the size of a tumor prior to surgery or irradiating diseased bone marrow before a transplant.

      Radiation treatments take place in special facilities, with the number and length of each dose taking place in accordance with each individual's treatment plan. Specialists monitor patients' response to treatment and often adjust the plan to best meet an individual's needs.

Side effects of treatment also vary according to the individual, with hair loss, fatigue, nausea, and vomiting being among the most common. Some patients don't experience any of these, have different side effects, or even have none at all.

      1.11.3 Chemotherapy

      It uses drugs to kill cancer cells. The chemicals used are cytotoxic, i.e. capable of halting the replication or growth of cancer cells, resulting in cell death [47,53,56]. Depending on the type of cancer and how the chemotherapy is combined with other treatments, it can come in many forms – pills, liquids, or injectables administered at home or under supervision in a facility. The specific cancer‐killing agent used, and the number and length of treatments, varies according to the type of cancer and the special circumstances of each patient, including their response to the therapy. Although chemotherapy drugs are designed to kill cancer cells, which reproduce more rapidly than normal cells, healthy tissues can also, unfortunately, be affected. This gives rise to certain side effects, which also vary by individual. The most common are hair loss, fatigue, nausea, and vomiting. Again, though, not all patients experience these particular effects, and may encounter different ones entirely or even none at all.

      1.11.4 Targeted Therapy

      It is similar to chemotherapy in that it utilizes drugs to attack and kill cancer cells; however, targeted therapy is designed to work specifically on mutated proteins found only in the cancer cells, thereby reducing the potential damage to other healthy tissues. Targeted therapy is often used in combination with other treatment modalities [53–55,57,60,67]. Although a seemingly ideal method to eliminate cancer, it still requires exposure to powerful chemicals, which can result in side effects such as hair and skin problems and high blood pressure.

      1.11.5 Immunotherapy