Neoplasia Flashcards
neoplasm
abnormal mass of tissue; growth of which exceeds and is uncoordinated w/ that of the normal tissues and persists after cessation of the stimulus which evoked the change
Neoplasia
New growth
Neoplasms arise from…
cells that have proliferative capacity; **mature neurons and cardiac myocytes don’t give rise to turmors
Things that can cause neoplasia
- mutations in genes that regulate growth
- apoptosis
- DNA repair
Anaplastic / cellular atypia
lack of differentiated features (morphologically or functionally) in cancers
- pleomorphism
- enlarged hyperchromatic nuclei
- atypical mitoses
- bizarre cells
What must cancers have?
Stem - like properties
- arise from tissue stem cells
- arise from more differentiated cells that transform and acquire the self renewal ability
benign
microscopic and gross characteristics are considered to be innocent; WILL NOT METASTASIZE OR INVADE
malignant
tumors collectively referred to as cancer; CAN INVADE, DESTROY, METASTASIZE TO DISTANT SITES AND CAUSE DEATH
What do benign and malignant relate to?
the biological behavior rather than morphology
Primary descriptor of any tumor
cell of origin
secondary descriptor of any tumor
morphologic or functional characteristics
Benign tumor suffix
- oma
Adenoma
benign, arises from a gland
epithelioma or papilloma
benign and arise form epithelial cells
medullary
soft and cellular w/ little stroma
comedo
with a duct
Malignant tumor suffix for EPITHELIAL cancers
carcinoma
Malignant tumor suffix for cancers of MESENCHYMAL origin
sarcoma
-emia
relationship to blood
Teratoma
benign tumor arising form germ cells (hair/teeth)
Hamartoma
localized, disordered differentiation during EMBRYOGENESIS that results in disorganized composition of the tissue elements of an organ
How may Hamartomas manifest?
either singly or in combination
1) abnormal quantity
2) abnormal structure
3) degree of maturation of the tissue components
Choriostoma
Ectopic islands of normal tissues
Hepatoma
malignant
melanoma
malignant
seminoma
malignant
lymphoma
malignant
Brenner tumor
malignant
Hodgkin disease
malignant
What 2 basic components do all tumors share? (both benign and malignant)
1) PARENCHYMA composed of transformed or neoplastic cells
2) STROMA - support tissue that is host derived and composed of connective tissue, blood vessels, and inflammatory cells
What is the gold standard for diagnosing a cancer?
Routine microscopy (there are no reliable molecular indicators)
Ewing sarcoma
malignant
What criteria are used to assess the true biological nature of a tumor?
Histological correlation of histologic and cytologic patterns w/ clinical outcomes
Fibrosarcoma and nodular fasciitis
Fibrosarcoma - malignant
Nodular fasciitis - benign; has a more alarming histologic appearance than many fibrosarcomas. Misdiagnosis can lead to unnecessary surgery.
Benign tumors and histologic and cytologic characteristics
benign tumors tend to be histologically and cytologically similar to their tissues of origin
Benign tumors and gross structure
May differ from tissue of origins; assume papillary and polypoid configurations
Malignant tumor morphology
- differ from parent tissue
What distinguishes malignant from benign tumors?
- differentiation and anaplasia
- rate of growth
- local invasion
- metastasis
Tumor markers
- products of malignant neoplasms that can be detected in body fluids or in affected cells
- can sometimes identify the cell or origin for metastases or a poorly differentiated primary tumor
- preserve the characteristics of cells of origins or have specific protein products that define a certain neoplastic cell
Types of markers include…
- immunoglobulins
- fetal proteins
- enzymes
- hormones
- cytoskeleton or junctional proteins
Why do we need to identify the lineage of a neoplasm that is poorly differentiated or undifferentiated?
Treatment decisions can be based on tumor markers that are present
Tumor marker roles outside of determining lineage
- can be used to screen for cancer
- can be used to follow progression or resolution of cancer
- can be therapeutic targets
PSA
prostate-specific antigen
screen for prostate carcinoma
evaluate for recurrence
CEA
carcinoembyronic antigen
GI malignancies progression or recurrence
CA 125
ovarian carcinoma progression or recurrence
HER2
therapeutic target for breast cancer
Immunohistochemistry
using antibodies to visualize certain tissues bound antigens
- conjugate an antigen to PEROXIDASE and there is a reaction that yields a color change
- conjugate the antibody to something that is fluorescent