Intro To Pathology And Neoplasia Flashcards
Define etiology.
The cause
Define pathology.
The study of disease
Define pathogenesis.
Mechanism of development
Define morphological/pathological changes.
Alterations in cells and organs
Define pathophysiology.
The functional changes associated with or resulting from disease or injury
What are the two major etiological factors?
Genetic
Acquired
What are some examples of diseases with acquired etiologies?
Caries
Traumatic Ulcer
Syphillis - chancre
What some examples of diseases with genetic etiologies?
Crouzon Syndrome - craniofacial dysostosis
Amelogenesis imperfecta
Familial denim atoms polyopsis
Define pathogenesis.
Sequence of events in the response of cells or tissues to the etiological agent, from the initial stimulus to the ultimate expression of the disease.
What’s the difference between a sign and a symptom?
A symptom is experienced and reported by the patient, while a sign is discovered by the physician during examination
What is a neoplasm?
An abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues and persists in the same excessive manner after cessation of the stimuli which evoked the change.
What are some distinguishing factors that can be used to differentiate between benign and malignant tumors?
Degree of differentiation
Rate of growth
Local invasiveness
Distant spread
What are some ways to describe benign tumors?
Small Well demarcated Slow growing Noninvasive Nonmetastic Well differentiated
What are some ways to describe malignant tumors?
Large Poorly demarcated Rapidly growing with hemorrhage and necrosis Locally invasive Metastic Poorly differentiated
What is dysplasia?
Non malignant cellular growth
Can be a precursor to malignancy
What are some causes of Dysplasia?
Chronic irritation
Chemical agents
Cigarette smoke
Chronic inflammatory irritation
What are some characteristics of dysplasia?
Disorganized, structureless maturation and spatial arrangement
Atypical cells without invasion
Acanthosis in the epithelium
What does the differentiation of parenchymal tumor cells refer to?
The extent to which they resemble their normal forebears morphologically and functionally
What is a Lipoma?
Well encapsulated adipose tissue with fat necrosis areas, fibrosis and calcification
What does in situ mean?
Abnormal cells that grow in their normal place (i.e. cancer that has stayed where it began and has not spread)
What is metaplasia?
Replacement of one cell type with another
What are some examples of metaplasia?
Squamous metaplasia in the cervix - changes due to HPV infection
Barrett’s esophagus - chronic inflammation from reflux
What is anaplasia?
Lack of differentiation
What are malignant neoplasms that are composed of undifferentiated cells are said to be what?
Anaplastic
What is considered to be a hallmark of malignancy?
Anaplasia
What is lymphatic spread favored by?
Carcinomas
What is hematogenous spread favored by?
Sarcomas
How do tumor cells break down the basement membrane?
Via proteolytic enzymes
Why are the liver and lungs most frequently involved in hematogenous dissemination?
Because all portal area drainage flows to the live and all naval blood flows to the lungs
What does “T” refer to in cancer staging?
The extent of the primary tumor. Goes from:
Tis (carcinoma in situ) to T4 (tumor directly invading other organs and tissues)
What does “N” refer to in staging?
Lymph node involvement.
Goes from:
N0 (no node involved) to N1 or N>=2 (few or multiple lymph nodes involved by tumor)
What does “M” refer to in staging?
Metastasis
Goes from:
M0 (absent) to M1 (present)
What are some general causes of cancer?
Geographic & Environmental Factors
Age
Hereditary
What can germ cell mutations lead to?
Structural birth defects
Inborn errors of metabolism
What are mutations that occur in non-germ cells called?
Somatic mutations
What is the clonal expansion principle?
A tumor can result if a mutation results in sufficient production of clones
What are 6 hallmarks that most cancer cells acquire though mutations in relevant genes?
Evading apoptosis Self-sufficiency in growth signals Insensitivity to anti-growth signals Sustained angiogenesis Limitless replicative potential Tissue invasion and metastasis
What is an oncogene?
Genes that promote autonomous cell growth in cancer cells
Mutated proto-oncogenes
Why do oncogenes cause cancer?
Mutations in proto-oncogenes that make them into oncogenes cause the cell to no longer stop at cell checkpoints to insure it is normal
Why can cells proliferate without external stimuli?
Usually because of oncogene activation
What is VEGF?
Vascular Endothelial Growth Factor
What VEGF do?
Promotes angiogenesis
Increases vascular permeability
Stimulates endothelial cell migration
Stimulates endothelial cell proliferation
VEGF-C selectively induces hyperplasia of lymphatic vasculature
Up-regulates endothelial expression of plasminogen activator, plasminogen activator inhibitor 1, and collagenase
What are ways that tumors may combat the hosts natural defenses?
Selective outgrowth of antigen-negative variants Loss or reduction of MHC molecules Apoptosis of Cytotoxic T cells Lack of co-stimulation Immunosuppression Antigen making
What are the 4 classes of regulatory genes that can lead to tumor formation?
Growth Promoting proto-oncogenes
Growth inhibiting tumor suppressor genes
Genes that regulate programmed cell death apoptosis
Genes involved in DNA repair
What is an example of a growth promoting proto-oncogene?
MYC
What is an example of growth inhibiting tumor suppressor genes?
P53
What are examples of genes that regulate programmed cell death?
Apoptosis
TNF
What are the genes involved in DNA repair?
Principle targets of genetic repair
BRCA1 and BRCA2
What is the single most common abnormality of proto-oncogenes in human tumors?
A point mutation of RAS family genes account for approximately 15 - 20 % of all human tumors
Carcinomas from colony and pancreas have mutations in what proto-onocogene?
KRAS
What is MYC?
A transcription factor and controls expression of several genes
What forms of cancer come from MYC?
Burkitt Lymphoma
Myelogenous leukemia
What are anti-VEGF therapies being used for?
They are being actively investigated as potential anti-cancer treatments, either as alternatives or adjuncts to conventional chemo or radiation therapy.
What are some techniques being used to block the VEGF pathway?
Neutralizing monoclonal Abs against VEGF or its receptor
Small molecule tyrosine kinase inhibitors of VEGF receptors
Soluble VEGF receptors which act as decoy receptors for VEGF
Ribozymes which target VEGF mRNA
What does HER2 encode for?
A cell surface receptor that can stimulate cell division
What protein has become an important biomarker and target of therapy for approx. 30% of breast cancer patients?
HER2/NEU
