NCM 112B - Oncology PDF

**CANCER** - Is a disease in which the body's cells multiply uncontrollably and form tumors. - These abnormal cells can invade and damage nearby tissues, and they can also spread to other parts of the body through the lymphatic or blood stream, forming metastases. --------------...

**CANCER** - Is a disease in which the body's cells multiply uncontrollably and form tumors. - These abnormal cells can invade and damage nearby tissues, and they can also spread to other parts of the body through the lymphatic or blood stream, forming metastases. ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- **Metastases** -The spread of cancer cells from the place where they first formed to another part of the body. In metastasis, cancer cells break away from the original (primary) tumor, travel through the blood or lymph system, and form a new tumor in other organs or tissues of the body. ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- - Cancer can affect any part of the body, and there are different types of cancer, such as lung, breast, colon, or skin cancer. - Cancer treatment may include surgery, chemotherapy, radiation therapy, or other therapies aimed at eliminating cancer cells and controlling the disease. - Cancer is a group of diseases characterized by uncontrolled and unregulated growth of cells. - Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. ------------------------------------------------------------------------------------------------------------- **Benign tumors** - are those that stay in their primary location without invading other sites of the body. ------------------------------------------------------------------------------------------------------------- - Cancer is often considered a disease of aging, with most cases diagnosed in those over age 55 years. However, it occurs in people of all ages - A disease marked by uncontrolled cell division. **BIOLOGY OF CANCER** What is Cancer? - Cancer is the uncontrolled growth of cells which may disrupt normal tissue function and cause potential harm to the body. **Two Major Dysfunctions** present in the process of cancer development are **[defective proliferation (growth)]** and **[defective cell differentiation. ]** A. **Defect in Cell Proliferation** - Normally, most tissues have a population of undifferentiated cells known as **stem cells.** ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ **Stem cells** - are the only cells in your body that make different cell types, like blood, bone and muscle cells. They also repair damaged tissue. Now, stem cells are essential for blood cancer and blood disorder treatments. ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ - These stem cells ultimately differentiate and become mature, functioning cells of a specific tissue. - Cell proliferation is the process by which a cell grows and divides 2 daughter cells **that leads to increase in cell number and rapid mechanism of tissue growth.** - Cell proliferation starts in the stem cell and begins when the stem cell enters the cell cycle. - The time from when a cell enters the cell cycle to when the cell divides into 2 identical cells is called the generation time of the cell. - A mature cell continues to function until it degenerates and dies. - All the body's cells are controlled by an intracellular mechanism that determines when cell proliferation is necessary.  Cell life cycle and metabolic activity. Generation time is the period from M phase to M phase. Cells not in the cycle but capable of division are in the resting phase (G0). - Under normal conditions, there is a state of dynamic equilibrium. This means cell proliferation equals cell degeneration or death. - Normally, the process of cell division and proliferation is activated only in the presence of cell degeneration or death (apoptosis).(one method the body use to get rid of unneeded or abnormal cells) - Cell proliferation also occurs if the body has a physiological need for more cells - Another means of proliferation control in normal cells is contact inhibition. Normal cells respect the boundaries and territory of the cells surrounding them. They will not invade a territory that is not their own. - Cancer cells grown in tissue culture have a loss of contact inhibition. No regard for cell boundaries and grow on top of one another and on top of or between normal cells. - The rate of normal cell proliferation (from the time of cell birth to the time of cell death) differs in each body tissue. In some tissues, such as bone marrow, hair follicles, and epithelial lining of the (GI) tract, the rate of cell proliferation is rapid. - In other tissues, such as myocardium and cartilage, cell proliferation does not occur or is slow. - Cancer cells proliferate at the same rate as the normal cells of the tissue from which they arise. - However, cancer cells respond differently from normal cells to the intracellular signals that regulate cell proliferation and death. - The result is that the proliferation of the cancer cells is indiscriminate and continuous. Sometimes they produce more than 2 cells at the time of mitosis. - In this way, there is continuous growth of a tumor mass, that is termed the pyramid effect. - The time needed for a tumor mass to double in size is known as its *doubling time.* B. **Defect in Cell Differentiation** - Cell differentiation is the process of cells becoming specialized in their structures and function and performing a certain job in the body. - Converting one cell type into another cell type. - Cell differentiation is normally an orderly process that progresses from a state of immaturity to a state of maturity. - Because all body cells are derived from the fertilized ova, all cells have the potential to perform all body functions. - As cells differentiate, this potential is repressed, and the mature cell can perform only specific functions. - With cell differentiation, there is a stable and orderly phasing out of cell potential. - Under normal conditions, the differentiated cell is stable and will not dedifferentiate, or return to its previous undifferentiated state. **Genetic Link** - Cancer involves the malfunction of genes that control differentiation and proliferation. - Two types of normal genes that can be affected by mutation. 1. 1.**Protooncogenes** - are normal cell genes that are important regulators of normal cell processes and promote growth. 2. Tumor suppressor genes suppress growth. - Mutations that change the expression of protooncogenes can cause them to function as **oncogenes** (tumor-inducing genes). - The protooncogene has been described as the genetic lock that keeps the cell in its mature functioning state. - When this lock is "unlocked," as may occur through exposure to carcinogens (agents that cause cancer) or oncogenic viruses, genetic alterations and mutations occur. - The abilities and properties that the cell had in fetal development are again expressed. Oncogenes can change a normal cell to a malignant one. - This cell regains a fetal appearance and function. - Tumor suppressor genes regulate cell growth. They prevent cells from going through the cell cycle. - Mutations can change tumor suppressor genes and make them inactive. This results in a loss of their tumor suppressing action - Examples of tumor suppressor genes are BRCA1and BRCA2. Alterations in these genes increase a person's risk for breast and ovarian cancer. - Another tumor suppressor gene is the **APC (Adenomatous Polyposis Coli) gene**. Mutations in this gene increase a person's risk for familial adenomatous polyposis, a precursor for colorectal cancer - Mutations in the p53(Tumor protein) tumor suppressor gene have been found in many cancers, including bladder, breast, colorectal, esophageal, liver, and ovarian cancers **DEVELOPMENT OF CANCER** - It has 3 stages: **initiation, promotion, and progression** A. **Initiation** - Cancer cells arise from normal cells because of changes in genes. The first stage, initiation, involves a mutation in the cell's genetic structure. - A mutation is any change in the usual DNA sequence - Gene mutations can occur in 2 ways: inherited from a parent (passed from one generation to the next) or acquired during a person's lifetime. - The genetic predisposition to cancer is thought to play a role in about 5 to 10% of all cancers. - Carcinogens (substances that can cause cancer), such as chemicals, physical factors, or biologic agents, cause mutations in the cellular DNA - Normally, these alterations are reversed by DNA repair mechanisms or the changes initiate programmed cellular death(apoptosis) or cell senescence. - Cells can escape these protective mechanisms with permanent cellular mutations occurring, but these mutations usually are not significant to cells until the second step of carcinogenesis   B. **Promotion** - Repeated exposure to promoting agents (co- carcinogens) causes proliferation and expansion of initiated cells with increased expression or manifestations of abnormal genetic information, even after long latency periods. - Promotion, the second stage in cancer development, is characterized by the reversible proliferation of the altered cells. - An increase in the altered cell population further increases the likelihood of more mutations - An important distinction between initiation and promotion is that the activity of promoters is reversible. - This is a key concept in cancer prevention. - Promoting factors include agents such as dietary fat, obesity, cigarette smoking, and alcohol use. - Changing a person's lifestyle to modify these risk factors can reduce the chance of cancer development C. **Progression** - Progression is the last stage in the natural history of a cancer. This stage is characterized by increased growth rate of the tumor, increased invasiveness, and *metastasis (spread of the cancer to a distant site).* - Certain cancers have an affinity for a particular tissue or organ as a site of metastasis (e.g., colon cancer often spreads to the liver). - The most common sites of metastasis are lungs, liver, bone, brain, and adrenal glands **ROLE OF THE IMMUNE SYSTEM IN RELATION TO CANCER** - The immune system defends the body against disease and infection caused by bacteria, viruses, fungus, or parasites. - It is a collection of the body\'s reactions and responses to damaged cells or infection. - As a result, it is also referred to as the **Immunological Response.** - The immune system is crucial for cancer patients because cancer can weaken the immune system, cancer treatments might weaken the immune system, and the immune system may help to fight cancer - The immune system distinguishes non-self from self by identifying foreign antigens. - Mutations in cancer cells can cause the development of tumor-specific antigens, changes in protein amount, processing, and subsequent antigen presentation, all of which can cause our immune systems to recognize them as non-self. - This is known as **Immune Surveillance** - The environment around neoplastic cells (including immune cells and immune modulators) has a significant role in selecting whether cells grow into tumors. - Poorly immunogenic neoplastic cells may be unnoticed and hence be chosen for. - This is known as **Cancer Immunoediting** - The immune system can help to fight cancer. - Some cells of the immune system can recognize cancer cells as abnormal and kill them. - But this may not be enough to get rid of a cancer altogether. - Some treatments aim to use the immune system to fight cancer - Some cancer therapies might temporarily suppress the immune system. *This is due to the fact that they can reduce the quantity of white blood cells produced in the bone marrow.* - Cancer therapies, such as chemotherapy, targeted cancer drugs, radiotherapy, and high doses of steroids, are more likely to damage the immune system - Angiogenesis may rise during inflammation as part of the intrinsic response to neoplastic cells as the body seeks to mend itself. - The creation of these new blood vessels, on the other hand, offers an excellent habitat for any neoplastic cells that may have avoided immune identification, providing them with a rich blood supply to encourage tumor growth. - Cancer can directly damage the immune system if it reaches the bone marrow, which is a critical manufacturing hub for immune cells - By growing into the bone marrow, cancer can damage the immune system. - The bone marrow produces blood cells that aid in the fight against infection. - This is most common in leukemia and lymphoma, although it can occur in other tumors as well. - Cancer can prevent the bone marrow from producing as many blood cells - The immune system has been related to the prevention and enhancement of metastatic spread. - **Concomitant Immunity** occurs when the formation of a primary tumor elicits an immune response that may be insufficient to eliminate the underlying tumor but inhibits the creation of other malignancies. - As a result, surgical excision of the initial tumor may relieve the inhibition of metastatic development, allowing additional tumor growth to occur **ETIOLOGY** **1. Viruses and Bacteria** - It is estimated that about 11% of all cancers worldwide are linked to viral infections (Schiller & Lowy, 2014). - After infecting individuals, DNA viruses insert a part of their own DNA near the infected cell genes causing cell division. - The newly formed cells that now carry viral DNA lack normal controls on growth - Examples of these viruses that are known to cause cancer include: - human papillomavirus (HPV) (cervical and head and neck cancers), - hepatitis B virus (HBV) (liver cancer) - Epstein-Barr virus (EBV) (Burkitt lymphoma and nasopharyngeal cancer) (Chen, Hsu, Yang, et al., 2014). - Helicobacter pylori is one bacterium identified as a significant cause of gastric cancer (Bessede, Dubus, Megraud, et al., 2014). **2. Physical Agents** - Physical factors associated with carcinogenesis include exposure to sunlight, radiation, chronic irritation or inflammation, tobacco carcinogens, industrial chemicals and asbestos. - Exposure to ionizing radiation can occur with repeated diagnostic x-ray procedures or with radiation therapy used to treat disease - Excessive exposure to the ultraviolet rays of the sun, especially in fair- skinned people, increases the risk of skin cancers. - Factors such as clothing styles (sleeveless shirts or shorts), the use of sunscreens, occupation, recreational habits, and environmental variables, including humidity, altitude, and latitude, all play a role in the amount of exposure to ultraviolet light **3. Chemical Agents** - Most hazardous chemicals produce their toxic effects by altering DNA structure. - This can occur in body sites distant from that of initial chemical exposure. - Tobacco smoke, thought to be the single most lethal chemical carcinogen, accounts for about one third of cancer deaths. - Passive smoke (i.e., secondhand smoke) has been linked to lung cancer; nonsmokers who live with a smoker have about a 20% to 30% greater risk of developing lung cancer. - There is evidence that passive smoke may be linked with childhood leukemia and cancers of the larynx, pharynx, brain, bladder, rectum, stomach, and breast (HHS, 2014) **4. Genetics and Familial Factors** - Almost every cancer type has been shown to run in families. This may be due to genetics, shared environments, cultural or lifestyle factors. - Genetic factors play a fundamental role in cancer cell development. - Cancer has been associated with extra chromosomes, too few chromosomes, or translocated chromosomes - Cancers with these underlying genetic abnormalities include chronic myelogenous leukemia, meningioma\'s, acute leukemia, retinoblastomas, and Wilms tumor. - In addition, certain syndromes represent a cluster of cancers identified by a specific genetic alteration that is inherited across generations. - In these families, the associated genetic mutation is found in all cells (it is germline and somatic) and represents an inherited susceptibility to cancer for all family members who carry the mutation **5. Lifestyle Factors** - The risk of cancer increases with long-term ingestion of carcinogens or co-carcinogens or the absence of protective substances in the diet. - Dietary substances that appear to increase the risk of cancer include fats, alcohol, salt-cured or smoked meats nitrate- and nitrite-containing foods, and red and processed meats. - Heavy alcohol use increases the risk of cancers of the mouth, pharynx, larynx, esophagus, liver, colon, rectum, and breast - Poor diet and obesity have been identified as contributing factors to the development of cancers of the breast (in postmenopausal women), colon, endometrium, esophagus, and kidney. - Obesity is also associated with an increased risk for cancers of the pancreas, gallbladder, thyroid, ovary, and cervix, and for multiple myeloma, - Hodgkin lymphoma, and an aggressive form of prostate cancer. - Multiple studies have long linked sedentary lifestyles and lack of regular exercise to cancer development **6. Hormonal Agents** - Tumor growth may be promoted by disturbances in hormonal balance, either by the body's own (endogenous) hormone production or by administration of exogenous hormones. - Cancers of the breast, prostate, and uterus are thought to depend on endogenous hormonal levels for growth. - Prenatal exposure to diethylstilbestrol (a synthetic form of the female hormone estrogen) has long been recognized as a risk factor for clear cell adenocarcinoma of the lower genital tract. - Hormonal changes related to the female reproductive cycle are also associated with cancer incidence. - Early onset of menses before age 12 and delayed onset of menopause after age 55, null parity (never giving birth), and delayed childbirth after age 30 are all associated with an increased risk of breast cancer. - Increased numbers of pregnancies are associated with a decreased incidence of breast, endometrial, and ovarian cancers - Women who take estrogen after menopause appear to have an increased risk of ovarian cancer. - Combination estrogen and progesterone therapy is linked to a higher risk of breast cancer **TYPES OF TUMOR** **5 Main Types of Tumor:** 1\. carcinoma 2\. sarcoma 3\. melanoma 4\. lymphoma 5\. leukemia - Carcinomas \-- the most commonly diagnosed cancers \-- originate in the skin, lungs, breasts, pancreas, and other organs and glands. - Lymphomas are cancers of lympnodes - Leukemia is cancer of the blood  **Tumors can be classified as benign or malignant.** - In general, benign neoplasms are well differentiated. - Malignant neoplasms range from well differentiated to undifferentiated - ***The ability of malignant tumor cells to invade and metastasize is the major difference between benign and malignant neoplasms*** **CLASSIFICATION OF CANCER** - Tumors can be classified according to anatomic site, histology (grading), and extent of disease (staging) - Tumor classification systems provide a standardized way to: - \(1) communicate the status of the cancer to all members of the interprofessional care team, - \(2) assist in determining the most effective treatment plan, - \(3) evaluate the treatment plan, - \(4) predict prognosis, and - \(5) compare groups for statistical purposes **ANATOMIC SITE CLASSIFICATION** - In the anatomic classification of tumors, the tumor is identified by the tissue of origin, anatomic site, and behavior of the tumor (e.g., benign or malignant) - **Carcinomas** originate from embryonal ectoderm (skin and glands) and endoderm (mucous membrane linings of the respiratory tract, GI tract, and genitourinary \[GU\] tract). - **Sarcomas** originate from embryonal mesoderm (connective tissue, muscle, bone, and fat). - **Lymphomas and leukemias** originate from the hematopoietic system **COMPARISON OF BENIGN AND MALIGNANT NEOPLASM** C:\\Users\\haydee bansale\\Downloads\\Picture1.png **HISTOLOGIC CLASSIFICATION** - In histologic grading of tumors, the appearance of cells and degree of differentiation are evaluated pathologically. - For many tumor types, 4 grades are used to evaluate abnormal cells based on the degree to which the cells resemble the tissue of origin. - Tumors that are poorly differentiated (undifferentiated) have a poorer prognosis than those that are closer in appearance to the normal tissue of origin (well differentiated) - ***Grade I:*** Cells differ slightly from normal cells (mild dysplasia) and are well differentiated (low grade). - ***Grade II:*** Cells are more abnormal (moderate dysplasia) and moderately differentiated (intermediate grade). - ***Grade III:*** Cells are very abnormal (severe dysplasia) and poorly differentiated (high grade). - ***Grade IV:*** Cells are immature, primitive (anaplasia), and undifferentiated; cell of origin is hard to determine (high grade). - ***Grade X:*** Grade cannot be assessed - Dysplasia refers to the abnormal development of cells within tissues or organs. - Loss of uniformity of individual cells and loss of their architectural orientation. - It can lead to various conditions that involve enlarged tissue, such as hip dysplasia. - It can also lead to the formation of precancerous cells. - Dysplasia can occur in any area of the body and can vary in degree of severity.  Hip Dysplasia: Symptoms, Causes & Treatment  **TNM CLASSIFICATION SYSTEM** - The TNM classification system is used to determine the anatomic extent of the disease involvement according to 3 parameters: - \(1) tumor size and invasiveness (T), - \(2) presence or absence of regional spread to the lymph nodes (N), - \(3) metastasis to distant organ site (M) - Carcinoma in situ (CIS) refers to a cancer whose cells are localized and show no tendency to invade or metastasize to other tissues. - CIS has its own designation in the system (Tis) because it has all the histologic characteristics of cancer except ***invasion***---a key feature of the TNM staging system. - ***Clinical staging*** is done at the completion of the diagnostic workup to guide treatment selection - ***Surgical staging*** refers to the extent of the disease as determined by surgical excision, exploration, and/or lymph node sampling. - After the extent of the disease is determined, the stage classification is set. - The original description of the extent of the tumor stays part of the record - If more treatment is needed, or if treatment fails, retreatment staging is done to determine the extent of the disease before retreatment. - ***"Restaging" classification (rTNM)*** is differentiated from the stage at diagnosis, since the clinical significance may be different - Other rating scales canbe used to describe and document the status of patients with cancer at the time of diagnosis, treatment, and retreatment and at each follow up examination. - For example, the Karnofsky Performance Scale and Katz Index of Independence in Activities of Daily Living describe patient's functional performance  **STAGES OF CANCER** - ***Stage 0:*** This stage describes cancer in situ. In situ means \"in place.\" Stage 0 cancers are still located in the place they started. They have not spread to nearby tissues. This stage of cancer is often curable. Surgery can usually remove the entire tumor. - ***Stage I:*** This stage is usually a cancer that has not grown deeply into nearby tissues. It also has not spread to the lymph nodes or other parts of the body. It is often called early-stage cancer - ***Stage II and Stage III:*** In general, these 2 stages are cancers that have grown more deeply into nearby tissue. - They may have also spread to lymph nodes but not to other parts of the body. - ***Stage IV:*** This stage means that the cancer has spread to other organs or parts of the body. - It may also be called advanced or metastatic cancer  **PREVENTION AND EARLY DETECTION OF CANCER** - Promoting healthy lifestyles. - Reducing risk factors - Early detection and prompt treatment are responsible for increased survival rates in patients with cancer. - Teach people to be familiar with their bodies. - Perform self-examinations and the 7 warning signs of cancer - Encourage them to seek immediate medical care if they notice a change in what is normal for them or if cancer is suspected. - Follow the recommended cancer screening guidelines for breast, colon, cervical, and prostate cancer from the American Cancer Society (ACS) is important - Limit alcohol use - Get regular physical activity (e.g., 30 minutes or more of moderate physical activity 5 times weekly). - Maintain a normal body weight. - Have regular physical examinations. - Obtain regular colorectal screenings. - Avoid cigarette smoking and other tobacco use. - Get regular mammography screening and Pap tests. - Be familiar with your own family history and risk factors for cancer - Obtain adequate, consistent periods of rest (at least 6 to 8 hours per night). - Use sunscreen with a sun protection factor of 15 or higher. - Avoid the use of tanning beds - Eliminate, reduce, or change the perception of stressors and enhance the ability to effectively cope with stress - Eat a balanced diet that includes vegetables and fresh fruits, whole grains, and adequate amounts of fiber. - Reduce dietary fat and preservatives, including smoked and salt-cured meats with high nitrite concentrations. - The goals of public education are to: - \(1) motivate people to recognize and change behaviors that may negatively affect health - \(2) encourage awareness of and participation in health promoting behaviors - When you teach about cancer, try to minimize the fear that surrounds the diagnosis **DIAGNOSIS** **7 Warning Signs of Cancer (CAUTION)** **C-** hange in bowel or bladder habits **A-** sore that does not heal **U-** nusual bleeding or discharge from any body orifice **T-** hickening or a lump in the breast or elsewhere **I-** ndigestion or difficulty in swallowing **O-** bvious change in a wart or mole **N-** agging cough or hoarseness  - Diagnostic studies depend on the suspected primary or metastaticsite(s) of the cancer. - Examples of diagnostic studies include: - Cytology studies (e.g., Pap test, bronchial washings) - Tissue biopsy - Chest x-ray - Complete blood count (CBC), chemistry profile - Liver function studies (e.g., aspartate aminotransferase \[AST\]) - Endoscopic examination: upper GI, sigmoidoscopy, or colonoscopy (including guaiac test for occult blood) - Radiographic studies (e.g., mammography, ultrasound, CT scan, MRI) - Radioisotope scans (e.g., bone, lung, liver, brain) **Liver function studies (e.g., aspartate aminotransferase \[AST\])** - AST (aspartate aminotransferase) is an enzyme that is found mostly in the liver, but it\'s also in muscles and other organs in your body. When cells that contain AST are damaged, they release the AST into your blood. An AST blood test measures the amount of AST in your blood. - The normal range is 8 to 33 U/L. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different samples. Talk to your health care provider about the meaning of your specific test results **Endoscopic examination: upper GI, sigmoidoscopy, or colonoscopy (including guaiac test for occult blood)** - Colonoscopy or sigmoidoscopy. Both tests use a thin tube with a camera to look inside your colon. - A colonoscopy allows your provider to see your entire colon. - Small samples of stool are placed on special cards coated with a chemical substance called guaiac and sent to a doctor or laboratory for testing. A testing solution is put on the cards and the guaiac causes the stool sample to change color. If there is blood in the stool, the color changes very quickly - MRI uses radio waves, while CT uses X-rays. - CT scans are used to diagnose different conditions than MRI scans. - For example, if you had a suspected fracture, a CT scan is more suitable for finding the problem. They are also more suited to emergency situations as the results are quicker - Magnetic resonance imaging produces clearer images compared to a CT scan - In instances when doctors need a view of soft tissues, an MRI is a better option than x-rays or CTs. - MRIs can create better pictures of organs and soft tissues, such as torn ligaments and herniated discs, compared to CT images **Mammography** - Mammography is the process of using low-energy X-rays to examine the human breast for diagnosis and screening. - The goal of mammography is the early detection of breast cancer, typically through detection of characteristic masses or microcalcifications. Mammography: What Is It And What To Expect?  Radioisotope scans (e.g., bone, lung, liver, brain) - A bone scan is a common type. A radionuclide is used which collects in areas where there is a lot of bone activity (where bone cells are breaking down or repairing parts of the bone). So a bone scan is used to detect areas of bone where there is cancer, infection, or damage - During a brain perfusion scan using a radiotracer, your healthcare provider will inject a radiotracer into a vein in your arm. (In other cases, you might inhale the radiotracer in the form of a gas.) Your provider will then use a special camera to detect the tiny radioactive particles emitted by the radiotracer Bone Scans: Uses, Side Effects, Procedure, Results - Examples of diagnostic studies include: - PET scan - Tumor markers (e.g., CEA, AFP, PSA, CA-125) - Genetic markers (e.g., BRCA1, BRCA2) - Molecular receptor status (e.g., estrogen and progesterone receptors) - Bone marrow examination (if a hematolymphoid malignancy is suspected or to document metastatic disease) **PET scan** - Positron emission tomography is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. - A PET scan shows how organs and tissues are working. This is different than MRI and CT scans. These tests show the structure of, and blood flow to and from organs  PET Scan: What It Is, Types, Purpose, Procedure & Results **Biopsy** - A biopsy is the removal of a tissue sample for pathologic analysis. - Various methods are used to obtain a biopsy depending on the location and size of the suspected tumor. - Percutaneous biopsy is often done for tissue that can be safely reached through the skin - Percutaneous biopsy is often done for tissue that can be safely reached through the skin - Endoscopic biopsy may be used for lung or other intraluminal lesions (esophageal, colon, bladder)  **Laparotomy:** - When a tumor is not easily accessible, a surgical procedure (laparotomy, thoracotomy, craniotomy) is often needed to obtain a piece of the tumor tissue. - Many radiographic techniques maybe used in conjunction with the biopsy procedure (e.g., CT, MRI, ultrasound-guided biopsy, stereotactic biopsy) to improve tissue localization **Stereotactic biopsy** - Stereotactic biopsy, also known as stereotactic core biopsy, is a biopsy procedure that uses a computer and imaging performed in at least two planes to localize a target lesion in three-dimensional space and guide the removal of tissue for examination by a pathologist under a microscope. - A stereotactic core biopsy uses a 3D scanning machine (ultrasound, CT scan or MRI) to find the precise location of a tumor. A sample is removed and looked at under a microscope. This test may also be called a stereotactic needle biopsy or x-ray-guided needle biopsy. It is most often used on breast and brain tumors - ***Fine-needle aspiration (FNA)*** may be done with a small-gauge aspiration needle that provide cells from the mass for cytologic examination. - Large-core biopsy cutting needles deliver an actual piece of tissue (core) that can be analyzed. - An advantage is that it preserves the histologic architecture of the tissue specimen - ***Excisional biopsy*** involves the surgical removal of the entire lesion, lymph node, nodule, or mass. - So, it is therapeutic as well as diagnostic. If an excisional biopsy is not feasible, an incisional biopsy (partial excision) may be done with a scalpel or dermal punch - ***Pathologic evaluation of a tissue sample*** is the only definitive way to diagnose cancer. - The pathologist examines the tissue to determine: - \(1) whether it is benign or malignant - \(2) the anatomic tissue from which the tumor arises (histology) - \(3) the degree of cell differentiation (histologic grade) **Other information that can be obtained includes:** - the extent of malignant involvement (size of tumor and depth) - evidence of invasiveness (extracapsular, lymphatic), - adequacy of surgical excision (positive or negative surgical margin status) - nuclear grade (mitotic rate) - Special staining techniques may give insight into responsiveness of the tumor to treatment or disease behavior (receptor status, tumor markers).