Neoplasia VI Flashcards
What type of UV light is particularly damaging?
UVB 280-320 nm
What does UVB light damage?
Pyrimidine dimers formed
What is the repair mechanism in the body to repair DNA?
Nucleotide excision repair (NER pathway)
What is xeroderma pigmentosum?
Patients without the enzyme needed for DNA repair in the NER pathway
What is the indirect effect of ionizing radiation? Direct?
indirect = Free radical generation
Direct = chromosome breakage
High LET (such as what) are more damaging than low LET (such as what)?
High = neutrons and alpha rays
Low = x-rays, gamma rays
Atomic bomb causes what CAs?
Leukemia (except CLL)
Thyroid cancer
What are the two CAs associated with x-ray workers?
Radiation dermatitis
Skin cancers
What is the CA associated with Radium use (like painting dials of watches with luminous radium)?
Osteosarcoma
What 3 organs are the least susceptible to atomic bomb radiation?
Skin
Bone
Gut
What are the two MOAs of hep B is causing hepatocellular carcinoma?
Chronic liver injury and regeneration
HBx protein activates IGF and binds to p53
What is the MOA of hep C causing CA?
Chronic liver cell injury and regeneration
What are the tumors associated with EBV? (4)
Burkitt’s lymphoma
Hodgkins
B-cell lymphoma
Nasopharyngeal carcinoma
Which HPV viruses are associated with cervical CA? Why?
16
18
31
33
These viruses integrate their DNA into the host
What is the function of E6 and E7 that HPV viruses produce?
E6 inhibits p53
E7 inhibits Rb
What are the two “low risk” virus strains of HPV? Why?
6 and 11–these do not integrate their DNA into the host
What virus causes T-cell leukemia/lymphoma?
HTVL-1 (human T-cell leukemia virus type I)
What is the mode of transmission for HTLV-1?
Intercourse
Blood
Breast feeding
What is the MOA of HTLV-1?
Tax gene has CD4 tropism.
Activates IL-2 (T cell growth factor)
c-Fos, GM-CSF
Inactivates p16INK4a
What is the molecule that HTLV-1 inactivates? What is the function of this molecule?
p16INK4a (an antiCA gene)
What is the virus that causes Kaposi’s sarcoma? What other virus is this associated with (but not caused by)?
HHV-8
Associated with HIV
How is helicobacter pylori infection associated with neoplasia?
CagA cytotoxin–stimulates growth factor pathway
What is the CA associated with H.Pylori?
MALT lymphoma (gastric lymphoma)
What are the CAs that estrogen promotes?
Breast CA
Cervical
Leiomyoma of uterus
What are the CAs associated with contraceptive hormones?
Breast CA
Benign/malignant liver tumors
What are the CAs associated with anabolic steroids?
Benign/malignant liver tumors
Leiomyomas are (encapsulated/not encapsulated)
Encapsulated
CA’s local or hormone production effects are related to what?
Location
What causes cancer cachexia?
TNFalpha production
What is paraneoplastic syndrome?
Distant effects of a tumor unrelated to primary tumor or metastasis
Lung CAs are known to produce what hormone? What does this cause?
ACTH–causes Cushing’s syndrome
Small cell carcinoma of the lung are known to produce what hormone? What is this syndrome called, an what metabolic disturbance is commonly found with this?
ADH
SIADH (hyponatremia)
What is acanthosis nigricans?
Black verrucoid appear leision of the skin (usually located in the axilla)
What is the CA associated with Acanthosis nigricans?
Stomach CA
What is the Leser Trelat sign associated with?
Gastric carcinoma that produces multiple outcroppings of pigmented seborrheic keratosis
What is carcinoid syndrome?
Tumors that produce 5HT, (associated with neuroendocrine tumors)
What is the tumor location of carcinoid tumors? What does the tumor produce?
Appendix
Serotonin
What are the clinical features of carcinoid syndrome?
Flushing of face, diarrhea, tachycardia
How do you diagnose carcinoid syndrome?
Urinary excretion of 5-hydroyindolacetic acid (5-HIAA)–a metabolite of serotonin
What causes hypercalcemia in malignancies? What is the CA associated with this?
Release of PTH related peptide
squamous cell carcinoma of the lung
What are the PTH levels in squamous cell carcinomas that release a PTH like hormone?
Low d/t hypercalcemia
Osteolytic bony metastasis is caused by what osteolytic factors? What CA is this associated with?
Release of osteolytic factors (PGE2, IL-1)
Breast CA
Medullary CA of the thyroid is associated with what condition? HOw does this occur?
Hypocalcemia–production of calcitonin
Gynecomastia is caused by what? What CA is this associated with?
B-HCG secretion
ChorioCA testis
What is Eaton-Lambert syndrome?
Autoimmune attack of neuromotor plate
What is the CA associated with Eaton-Lambert syndrome?
Small cell carcinoma of the lung
What are the morphological methods to diagnose CA?
- Biopsy
- Frozen section
- FNAC
- Cytology
- IHC
What are the two molecular methods for diagnosing CA?
Flow cytometry
DNA probe
What is the biochemical assay utilized to diagnose CA looking for?
Tumor markers
Why should you use IHC?
Diagnose an undifferentiated tumor
Categorize leukemias and lymphomas
If the tumor is positive for cytokeratin or epithelial membrane antigen, it indicates that the CA came from what type of cells?
Epithelial cells
Vimentin and desmin are markers for what CA types?
Mesenchymal origin
LCA (leukocyte common antigen) is a marker for what type of CA?
Leukocyte origin
Neuron-specific enolase (NSE) is associated with what?
Neuronal tumors
Chromogranin is associated with what CAs?
Neuronal tumors
Synaptophysin is associated with what CAs?
Neuronal tumors
Thyroglobulin marker for a tumor = what origin for a tumor?
Thyroid CA
CD10 (CALLA) = what origin?
Acute lymphoblastic leukemia
Placental alkaline phosphatase is a marker for what CA?
Seminoma
vWF, CD31 is a marker for what types of CA?
Vascular neoplasms
What is a tumor marker?
A substance found in the blood, urine, or body tissues that can be elevated in CA, among other tissue types
Increase in CEA = what CAs?
Colon CA
Breast
Stomach
Pancrease
Increase in PSA= what CAs?
Prostate
Increase in beta-HCG= what CAs?
Trophoblastic tumors (choriocarcinoma)
Increase in CA-125= what CAs?
Ovarian carcinoma
Increase in a-fetoprotein (AFP)= what CAs?
Hepatocellular carcinomas
Germ cell tumors of testes or ovaries
Increase in NSE= what CAs?
Small cell carcinoma of the lung
Increase in Calcitonin = what CAs?
Medullary thyroid carcinoma
Increase in CA 19-9= what CAs?
Colon
Pancreatic
Increase in CA 15-3= what CAs?
Breast carcinoma