Chapter 8Neoplasia : Chapter 8Neoplasia
Objectives : Objectives Define neoplasm and explain how neoplastic growth differs from the normal adaptive changes seen in atrophy, hypertrophy, and hyperplasia
Distinguish between cell proliferation and differentiation
Describe the phases of the cell cycle
Explain the function of cyclins, cyclin-dependent kinases, and cyclin-dependent kinase inhibitors in terms of regulating the cell cycle
Describe the properties of stem cells
Objectives : Objectives Cite the method used for naming benign and malignant neoplasms
State at least five ways in which benign and malignant neoplasms differ
Relate the properties of cell differentiation to the development of a cancer cell clone and the behavior of the tumor
Trace the pathway for hematologic spread of a metastatic cancer cell
Use the concepts of growth fraction and doubling time to explain the growth of cancerous tissue
Objectives : Objectives Describe various types of cancer-associated genes and cancer-associated cellular and molecular pathways
Describe genetic events and epigenetic factors that are important in tumorigenesis
State the importance of cancer stem cells, angiogenesis, and the cell microenvironment in cancer growth and metastasis
Explain how host factors such as heredity, levels of endogenous hormones, and immune system function increase the risk for development of selected cancers
Objectives : Objectives Relate the effects of environmental factors such as chemical carcinogens, radiation, and oncogenic viruses to the risk of cancer development
Identify concepts and hypotheses that may explain the processes by which normal cells are transformed into cancer cells by carcinogens
Describe the many possible ways by which cancer acts to disrupt organ function
Characterize the mechanisms involved in the anorexia and cachexia, fatigue and sleep disorders, anemia, and venous thrombosis experienced by patients with cancer
Objectives : Objectives Define the term paraneoplastic syndrome and explain its pathogenesis and manifestations
Cite three characteristics of an ideal screening test for cancer.
Describe the four methods that are used in the diagnosis of cancer
Differentiate between the methods used for grading and staging of cancers.
Explain the mechanism by which radiation exerts its beneficial effects in the treatment of cancer
Describe the adverse effects of radiation therapy
Objectives : Objectives Differentiate between the action of direct DNA-interacting and indirect DNA-interacting chemotherapeutic agents and cell cycle–specific and cell cycle–independent drugs
Describe the three mechanisms whereby biotherapy exerts its effects
Describe three examples of targeted therapy used in the treatment of cancer
Objectives : Objectives Cite the most common types of cancer affecting infants, children, and adolescents
Describe how cancers that affect children differ from those that affect adults.
Discuss possible long-term effects of radiation therapy and chemotherapy on adult survivors of childhood cancer
Characteristics of Cancer : Characteristics of Cancer Disorder of altered cell differentiation and growth
Results in neoplasia (“new growth”)
Growth is uncoordinated and relatively autonomous
Lacks normal regulatory controls over cell growth and division
Tends to increase in size and grow after stimulus ceases or needs of organism are met Learning Objective 1: Define neoplasm and explain how neoplastic growth differs from the normal adaptive changes seen in atrophy, hypertrophy, and hyperplasia.
Components of Tissue Renewal and Repair : Components of Tissue Renewal and Repair Cell proliferation
Process of cell division
Inherent adaptive mechanism for replacing body cells
Cell differentiation
Process of specialization
New cells acquire the structure and function of cells they replace
Apoptosis
Form of programmed cell death to eliminate unwanted cells Learning Objective 2: Distinguish between cell proliferation and differentiation
The Cell Cycle : The Cell Cycle Definition: the interval between each cell division
Genetic information is duplicated
Duplicated chromosomes are appropriately aligned for distribution between two genetically identical daughter cells
Checkpoints in cycle provide opportunities for monitoring the accuracy of DNA replication
Cyclin, cyclin-dependent kinase, cyclin-dependent kinase inhibitors Learning objectives 3 & 4
Phases of the Cell Cycle : Phases of the Cell Cycle G1 (gap 1): the post mitotic phase
DNA synthesis ceases while RNA and protein synthesis and cell growth take place
S phase: DNA synthesis occurs, giving rise to two separate sets of chromosomes, one for each daughter cell.
G2 (gap 2): the premitotic phase
DNA synthesis ceases; RNA and protein synthesis continue.
M phase: the phase of cellular division or mitosis Learning Objective 4: Explain the function of cyclins, cyclin-dependent kinases, and cyclin-dependent kinase inhibitors in terms of regulating the cell cycle.
Categories of Cell Types of the Body : Categories of Cell Types of the Body Well-differentiated neurons and cells of skeletal and cardiac muscle unable to divide and reproduce
Parent or progenitor cells that continue to divide and reproduce
Blood cells, skin cells, liver cells
Undifferentiated stem cells that can be triggered to enter cell cycle and produce large numbers of progenitor cells when needed Learning Objective 5: Describe the properties of stem cells.
Stem Cells : Stem Cells Definition: reserve cells that remain quiescent until there is a need for cell replenishment
When a stem cell divides, one daughter cell retains the stem cell characteristics, and the other daughter cell becomes a progenitor cell that proceeds through to terminal differentiation.
Self-renewal
Potency Learning Objective 5: Describe the properties of stem cells.
Types of Stem Cells : Types of Stem Cells Unipotent: give rise to one type of differentiated cell
Muscle satellite cell
Epidermal stem cell
Spermatogonium
Basal cell of the olfactory epithelium
Oligopotent: produce small number of cells
Pluripotent: give rise to numerous cell types Learning Objective 5: Describe the properties of stem cells.
Question : Question Which of the following cell types is more likely to have arisen from a stem cells in an adult?
Muscle
Bone
Epithelial
Neural
Answer : Answer Muscle
Bone
Epithelial cells: Epithelial cells such as skin, organ lining, and vessel lining cells are constantly being replaced.
Neural
Tumors : Tumors Mass of cells due to overgrowth
Neoplasms
Malignant
Benign
Named by adding the suffix -oma to the parenchymal tissue type from which the growth originated Learning objectives 6 & 7
Types of Tumors : Types of Tumors Adenoma: benign tumor of glandular epithelial tissue
Adenocarcinoma: malignant tumor of glandular epithelial tissue
Carcinoma: malignant tumor of epithelial tissue
Osteoma: benign tumor of bone tissue
Sarcoma: malignant tumors of mesenchymal origin
Papilloma: benign microscopic or macroscopic fingerlike projection growing on a surface Learning Objective 7: State at least five ways in which benign and malignant neoplasms differ.
Factors Differentiating Benign and Malignant Neoplasms : Factors Differentiating Benign and Malignant Neoplasms Cell characteristics
Manner of growth
Rate of growth
Potential for metastasizing or spreading
Tendency to cause tissue destruction
Capacity to cause death Learning Objective 7: State at least five ways in which benign and malignant neoplasms differ.
Characteristics of Benign Neoplasms : Characteristics of Benign Neoplasms A slow, progressive rate of growth that may come to a standstill or regress
An expansive manner of growth
Inability to metastasize to distant sites
Composed of well-differentiated cells that resemble the cells of the tissue of origin Learning Objective 7: State at least five ways in which benign and malignant neoplasms differ.
Characteristics of Malignant Neoplasms : Characteristics of Malignant Neoplasms Tend to grow rapidly and spread widely
Have the potential to kill regardless of their original location
Tend to compress blood vessels and outgrow their blood supply, causing ischemia and tissue necrosis
Rob normal tissues of essential nutrients
Liberate enzymes and toxins that destroy tumor tissue and normal tissue Learning objectives 7 & 8
Methods by Which Cancer Spreads : Methods by Which Cancer Spreads Direct invasion and extension
Seeding of cancer cells in body cavities
Metastatic spread through the blood or lymph pathways Learning objectives 8, & 9
Factors Affecting Tumor Growth : Factors Affecting Tumor Growth The number of cells that are actively dividing or moving through the cell cycle
The duration of the cell cycle
The number of cells that are being lost compared with the number of new cells being produced
Growth fraction is the ratio of dividing cells to resting cells in a tissue mass.
Doubling time is the length of time it takes for the total mass of cells in a tumor to double. Learning Objective 10: Use the concepts of growth fraction and doubling time to explain the growth of cancerous tissue.
Genes That Control Cell Growth and Replication : Genes That Control Cell Growth and Replication Proto-oncogenes
Tumor suppressor genes
Genes that control programmed cell death or apoptosis
Genes that regulate repair of damaged DNA Learning Objective 11: Describe various types of cancer-associated genes and cancer-associated cellular and molecular pathways.
Steps Involving the Transformation of Normal Cells Into Cancer Cells : Steps Involving the Transformation of Normal Cells Into Cancer Cells Initiation
Cells exposed to doses of carcinogenic agents, making them susceptible to malignant transformation
Promotion
Unregulated, accelerated growth in already initiated cells caused by various chemicals and growth factors Learning Objective 12: Describe genetic events and epigenetic factors that are important in tumorigenesis.
Steps Involving the Transformation of Normal Cells Into Cancer Cells : Steps Involving the Transformation of Normal Cells Into Cancer Cells Progression
Tumor cells acquire malignant phenotypic changes that promote invasiveness, metastatic competence, autonomous growth tendencies, and increased karyotypic instability. Learning Objective 12: Describe genetic events and epigenetic factors that are important in tumorigenesis.
Host and Environmental Factors Leading to Cancer : Host and Environmental Factors Leading to Cancer Heredity
Hormones
Carcinogens
Chemical
Radiation
Oncogenic viruses
Immunologic mechanisms Stem cells
Angiogenesis
Angiogenic factor production or loss of angiogenic inhibitors
Microenvironmental effects
Multiple cell types, cytokines, and growth factors Learning objective 13, 14,15 & 16
Clinical Manifestations of Cancer : Clinical Manifestations of Cancer Tissue integrity
Compressed and eroded blood vessels, ulceration and necrosis, frank bleeding, and hemorrhage
Cancer cachexia
Weight loss and wasting of body fat and muscle tissue; profound weakness, anorexia, and anemia
Paraneoplastic syndromes
Inappropriate hormone release, circulating hematopoietic, neurologic, and dermatologic factors Learning objective 17, 18, & 19
Diagnostic Measures for Cancer Detection : Diagnostic Measures for Cancer Detection Lab tests
Pap smear
Biopsy
Cytologic studies and tissue biopsy
Endoscopic examinations
Ultrasound
X-ray studies, MRI
CT and PET
Tumor markers Staging and grading of tumors
Screening for early detection
Observation
Palpation
Laboratory tests Learning objective 20, 21, & 22
Question : Question Which of the following does not apply to benign tumor cells?
A slow, progressive rate of growth that may come to a standstill or regress
An expansive manner of growth
Liberation of enzymes and toxins that destroy tumor tissue and normal tissue
Composed of well-differentiated cells that resemble the cells of the tissue of origin
Answer : Answer A slow, progressive rate of growth that may come to a standstill or regress
An expansive manner of growth
Liberation of enzymes and toxins that destroy tumor tissue and normal tissue is an ability that characterizes metastatic tumor cells: Benign tumor cells do not liberate destructive enzymes and toxins.
Composed of well-differentiated cells that resemble the cells of the tissue of origin
Goals of Cancer Treatment : Goals of Cancer Treatment Curative
Control
Palliative
Cancer Treatment Modalities : Cancer Treatment Modalities Surgery
Radiation
Hormonal therapy
Targeted therapy
Biotherapy
Immunotherapy
Biologic response Chemotherapy
Direct DNA-interacting
Indirect DNA-interacting
Cell-cycle specific
Cell-cycle nonspecific Learning objectives 23, 24, 25, 26, & 27
Types of Surgery for Cancer : Types of Surgery for Cancer Cryosurgery: instilling liquid nitrogen into the tumor through a probe
Chemosurgery: using corrosive paste with multiple frozen sections to ensure complete removal of tumor
Laser surgery: using a laser beam to resect tumor
Laparoscopic surgery: performing surgery through two small incisions
Stem Cell Transplantation : Stem Cell Transplantation Bone marrow transplantation (BMT)
Peripheral blood stem cell transplantation (PBSCT)
Two treatment approaches for individuals with leukemias, certain solid tumors, and other cancers previously thought to be incurable
Common Solid Tumors of Childhood : Common Solid Tumors of Childhood Brain and nervous system tumors
Neuroblastoma
Wilms tumor
Rhabdomyosarcoma and embryonal sarcoma
Retinoblastoma
Osteosarcoma
Ewing sarcoma Learning objective 28 & 29
Characteristics of Childhood Cancers : Characteristics of Childhood Cancers Most involve the hematopoietic system, nervous system, or connective tissue
Heritable forms of cancer tend to have
An earlier age of onset
A higher frequency of multifocal lesions in a single organ
Bilateral involvement of paired organs or multiple primary tumors
Question : Question Is the following statement true or false?
Radiation is a common treatment for childhood cancers.
Answer : Answer False: It has been shown that radiation will have long- lasting effects, whereas other methods of treatment are not as damaging.