Neoplasia (7) Flashcards
Clonal process initiated by a genetic mutation conferring growth advantage on involved cells
Neoplasia
2 types of neoplasia?
Benign
Malignant
What is the main way to distinguish a benign neoplasia from a malignant neoplasia?
Benign = LOCALIZED Malignant = invasive and metastasizes
Cancer is considered what type of neoplasia?
Malignant neoplasia
Benign and Malignant neoplasias - edge type
Benign - Intact and encapsulated edge
Malignant - irregular, heterogenous and infiltrative edge
Benign and Malignant neoplasias - growth
Benign - Exophytic growth (above surface)
Malignant - Endophytic growth (into surface)
Benign neoplasias usually end in what suffix?
“oma”
Through what mechanisms do benign neoplasias do harm?
Compression of structures
Hemorrhage
Hormone secretion
Malignant neoplasias from mesenchyme suffix?
Sarcoma
Sarcoma
Malignant mesenchymal derived neoplasia
Malignant neoplasias from epithelium suffix?
Carcinoma
Carcinoma
Malignant epithelial derived neoplasia
Malignant neoplasias from blood cells?
Leukemia
Lymphoma
Myeloma
Melanoma, Mesothelioma and Seminoma - benign or malignant?
Malignant
- Exceptions to the naming conventions
Mesenchymal tissue examples
Bone, muscle, fat, tendons, blood vessels
- sarcomas
Epithelial tissue examples
Skin, mucous, glandular, lining epithelium
- carcinomas
Cell are responsible for invasion and spread. What surrounds them?
Stroma - forms tumor friendly micro-environment
Teratoma forms from?
Totipotent stem cells
A Teratoma includes?
Elements derived from epithelial AND mesenchymal elements
= More than 1 germ cell layer present
Hamartoma
Overgrowth of mature tissues but with disorganization and often 1 dominating element
What is an example of a hamartoma?
Large polyp in the bowel – normal elements just weirdly organized
Hamartomas as what type of neoplasm?
Benign
Choristoma
Mass of tissues from another part of the body in the wrong location
What is an example of a Choristoma?
Pancreatic tissue in the stomach
What are the morphologic changes that lead to cancer?
- Metaplasia
- Dysplasia
- Carcinoma in situ
Metaplasia
1 cell type is replaced with another
Metaplasia leads to?
Dysplasia
Dysplasia
Disordered growth
Dysplasia leads to?
Carcinoma in situ
Carcinoma in situ
Full thickness; severe dysplasia
Has yet to penetrate basement membrane
Degree of differentiation reflects?
How much the neoplasm resembles the original tissue cells
Well differentiated =
Lots of resemblance to original cells
Poorly differentiated =
Not much resemblance to original cells
Anaplasia
NO differentiation (NO resemblance)
Pleomorphism
Variability in cell shape and size
Immunostains, hormone secretion amount and serum tumor markers all reflect what degree of differentiation?
Well differentiated (still similar to normal tissues)
With acute leukemias, cancer cells are halted at the ____ stage
Blast
With chronic leukemias, cancer cells are halted at the ____ stage
Mature
Benign and Malignant - degree of differentiation
Benign - well differentiated
Malignant - poor differentiation
Benign and Malignant - rate of progression
Benign - SLOW; rare to see mitotic figures
Malignant - ERRATIC, can be fast or slow; mitotic figures are numerous
The more mitotic figures means?
The faster the rate of growth
Benign and Malignant - metastasis?
Benign - NO
Malignant - YES
What are 3 types of metastasis?
- Lymphatic spread
- Hematogenous spread
- Direct seeding
Lymphatic spread
Cancer cells gain entry into lymphatics
What type of metastasis is the most common route for carcinomas?
Lymphatic spread
When tracer dye is injected into the tumor, the first lymph node to take up the dye is considered?
Sentinel node
Why is identifying the sentinel node important?
Can remove only that one and save other lymph nodes from having to be taken out
What type of metastasis the most common route for sarcomas?
Hematogenous mets
Primary targets of Hematogenous mets?
Lungs, liver, bone
TNM staging
T - tumor size
N - degree of nodal mets
M - presence or absence of distal mets
Most common cancer diagnosis for men and women?
Men - prostate
Women - breast
Most common cancer deaths for men and women?
LUNGS
Why are cancer deaths on the decline?
Decreased smoking and increased screening
What are 7 cancers associated with smoking?
Oral Pharynx Larynx Esophagus Lungs Bladder Pancreas
What are 4 occupational cancer agents?
Asbestos
Benzene
Radon
Vinyl Chloride
Vinyl chloride is associated with cancer?
Hepatic angiosarcoma
Childhood cancer is associated with what type of mutations?
Germline
What are 3 acquired predisposing factors for cancer?
Chronic inflammation
Immunodeficiency
Precursor lesions
Are benign neoplasms usually precursors for their malignant counterparts?
NO
What is an exception to the rule that benign neoplasms are not precursors for their malignant counterparts?
Colon adenoma –> carcinoma
What is paraneoplastic syndrome?
Tumor secretes substances and evokes cytokines and antibodies
Paraneoplastic syndrome of squamous carcinoma?
Humoral hypercalcemia of malignancy
Paraneoplastic syndrome of small cell carcinoma?
Cushing syndrome
Paraneoplastic syndrome of pancreatic carcinoma?
Thrombi formation
Paraneoplastic syndrome of acute promyelocytic carcinoma?
Disseminated intravascular coagulation
Direct carcinogen
Carcinogenic from the start
Indirect carcinogen
Metabolic process must occur before substance is carcinogenic
What is responsible for converting indirect carcinogens into active carcinogens?
Cytochrome P450
UVB rays create?
Pyrimidine dimers that distort DNA
What normally corrects the pyrimidine dimers?
Nucleotide excision repair
Xeroderma Pigmentosum has defects in?
Nucleotide excision repair
What is seen with xeroderma pigmentosum?
Familial melanomas due to inability to correct mutations caused by UV rays
Ionizing radiation can cause carcinogenesis even years after exposure. What types of cancers were seen later on after japan atomic bombs and chernobyl?
Japan atomic bombs - colon, breast, lung
Chernobyl - thyroid
