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81 Cards in this Set

  • Front
  • Back
What are some basic properties of tumor cells?
ANY cell in body can give rise to a tumor: typically retains some physically characteristics of original cell

functional abnormalities

tumor autonomy: 6 hallmarks of cancer

tumor heterogeneity: conglomerates of clonally selected subsets of cells
What is grading?
microscopic evaluation of tumor tissue to help determine aggressiveness of tumor
What are some differences b'twn normal & tumor vasculature?
-tumors elaborate angiogenesis factors to stimulate new vessel formation
-tumor vasculature is abnormal: BM & endothelial cells may be missing, tortuous & disorganized, less dense, altered blood flow (may stop or reverse), usually more dilated
-may lead to areas of hypoxia, acidosis, & nutrient deprivation: significant clinical implications for chemo & radiation tx
What are some factors that influence local invasion of a tumor?
rate of growth, ↑ motility of tumor cells, loss of contact inhibition, elaboration of proteolytic enzymes  degradation of basement mem, pathways of least resistance (fascial planes, lymphatics, blood), transcoelemic spread (shedding of tumor cells or emboli to serosal surfaces: carcinomatosis, HSA)
What are the parts of the metastatic cascade?
transformation: development of a heterogeneous tumor
angiogenic switch: tumor recruits its own blood supply
motility & invasion: selection of tumor cell clones w/ distinct growth advantage & acquistion of invasive phenotype
cell-cell adhesion changes
survival in circulation
tumor cell arrest & adherence
extravasation: tumor cells leave vessels before proliferating
angiogenesis of metastatic foci
evasion of immune response
Carcinomas are of _______ origin & usually spread via ________.
epithelial

lymphatics
Sarcomas are of _______ origin & usually spread via ________.
mesenchymal

blood
Round cell tumors are of _______ origin & usually spread via ________.
hematopoietic

lymphatics and blood
What are 3 important initial questions to ask yourself when presented w/ a patient w/ a mass?
what is it?
where is it?
how can I get rid of it?
What is staging?
diagnostic tests designed to determine if 1 must worry about local dz or systemic dz or both
What diagnostics are ALWAYS included in work up of a patient w/ a mass?
thorough PE
CBC/Chem/U/A
survey chest rads to detect mets
abdominal U/S to examine abdominal organs & ln’s
What are some additional diagnostics that can be included in work up of a patient w/ a mass?
FNA: cytologically assess masses &/or enlarged ln
-can be used alone for cutaneous masses or w/ U/S guidance for internal masses

BM aspirate: always indicated w/ patients who have CBC abnormalities & as part of lymphoma staging

CT/MRI: determine extent & invasiveness of a wide variety of tumors
-MRI usually reserved to delineate brain tumors
-CT: can be used for soft tissue sarcomas, nasal tumors, bone tumors, etc.

bx
What are some types of biopsies?
excisional
incisional: punch, wedge, tru-cut
endoscopic
laparoscopic or thorascopic
image-guided
What are indications for excisional bx?
• used for freely movable, small cutaneous masses w/ no adjacent tissue invasion
• ONLY when complete tumor removal is histologically verified & tumor is benign or a low-grade malignancy
What are indications for incisional biopsy?
• used for large tumors
• recommended if a definitive dx or histological grade would influence tx decision
What is the TNM tumor staging system?
• T (tumor): based on size &/or extent of tumor invasion
• N (node): based on extent of lymph node involvement
• M (metastasis): indicates whether distant mets are present
What are some benefits of staging tumors?
• determines extent of macroscopic dz
• framework for rational tx planning
• facilitates communication b’twn clinicians
• uniform comparison & evaluation of tx results & aid in prognostication
What are indications for use of surgery as a treatment modality?
- removal of bulk tumors entirely or in a cytoreductive approach to achieve microscopic dz
- cancer prevention: mammary neoplasia
- oncologic emergencies: obstruction/perforation, complications related to chemo or radiotherapy

aggressive initial surgical management of neoplasia may be the most important principal for improved cancer control

- primarily used for localized or regional neoplasms
- en bloc LN removal can be considered if metastatic dz is confirmed or suspected
- can be used to tx metastatic dz if tumor is slow growing or is causing functional impairment or morbidity (palliative)
What are some principles of cancer sx?
- surgical field based on bx results, imaging results, knowledge of tumor behavior & size, & physical constraints or limitations of surrounding tissues
- marginal excision is rarely sufficient unless post-op adjunctive therapy (i.e. radiation) is to be used
- protect normal tissue: change gloves & instruments
- minimize tumor manipulation
- ligate vascular & lymphatic vessels early to minimize tumor emboli shedding
- fulgurate &/or electrocautery if tumor margins are disrupted
- beware of pseduocapsules (soft tissue sarcomas)
What are indications for use of radiation as a treatment modality?
- mainly for local & regional neoplasia (ex. distal limb tumors)
- can be used for pain palliation (ex. OSA) or metastatic dz
What are the principles of radiation therapy?
-most effective in setting of microscopic dz
-most often used in conjunction w/ surgery (either pre-op or post-op)
-most round cell tumors respond well
-tumor, regional nodes, & a margin of normal tissue should be in radiation field if possible
-radiation dose administered should be maximum dose tolerated by adjacent normal tissues
-damage to normal tissue is minimized by accurate tx planning
-CT/MRI scans of affected region are necessary to obtain optimal tx plan that generally involves multiple overlapping tx fields from different directions
-toxicity from radiation can be acute, occurring during therapy or in 1st few weeks after irradiation (ex. mm inflammation, moist desquamation, hair loss, tissue inflammation), or late, occurring many months or years after tx (ex. contraction & fibrosis, tissue necrosis, cataract formation, etc).
What are indications for use of chemo as a treatment modality?
o best in setting of microscopic dz
o targets ALL rapidly dividing tissue
o all chemo in dogs & cats is palliative: NOT curative
o most round cell tumors sensitive to chemo, most sarcomas & carcinomas are NOT
What are the principles involved in multi-agent chemo protocols?
- only those agents proven effective alone should be used
- each agent should have a different mechanism of action
- each drug should have a different spectrum of toxicity & (ideally) of resistance
- each drug should be used at maximum dose
- agents w/ similar dose-limiting toxicities can be combined safely only by reducing doses, resulting in ↓ effects
- drug combinations should be administered in shortest interval b’twn therapy cycles to allow for recovery of normal tissue
What is cancer cachexia & how is it treated?
moderate to severe weight loss in face of adequate nutritional intake

tx is directed towards early elimination of cachexia syndrome (by elimination of neoplasia) & supportive care to minimize its effects during interim
What are some alternative/experimental methods of treating neoplasia?
hyperthermia
immunotherapy
photodynamic therapy
gene therapy
anti-angiogenesis/anti-vascular therapy
inhibitors of cell signaling: tyrosine kinase inhibitors
canine lymphoma

a. signalment
b. clinical signs
a. age: 7-10 yo
breeds: bassets, St. Bernard, Scottie, goldens, rottweilers, labs
rarely seen in mixed breeds
b. o extremely variable: none to extremely ill
o most dogs present w/ variable signs & peripheral &/or internal lymphadenopathy
- ddx for lymphadenopathy: systemic fungal, infectious, inflammatory, immune-mediated, other neoplasia
What are the clinical forms of canine lymphoma?
multicentric: most common (~80%)
• generalized enlarged peripheral ln’s

alimentary: tumors arise in lymphoid tissues in GI tract & spread to abdominal nodes  GI signs
• common in boxers, goldens
• hard to tx

mediastinal: often effusion & tumors often large at dx --> upper GI or respiratory signs

cutaneous
• variable appearance
• dx w/ bx
• epitheliotropic: T cells (CD3+): mycosis fungoides also affects oral mucosa: lymphocytes in surface epi; poor px
• non-epitheliotropic: B cells (CD79+); affects the mid to deep dermis; “B” is better

other: CNS, ocular, renal, splenic (virtually any organ or site may be affected)
What are some possible diagnostic findings w/ canine lymphoma?
hematology: often normal; anemia, thrombocytopenia, leukopenias
chem.: hypercalcemia (of malignancy), hyperbilirubinemia
U/A: SG, bacteriuria, proteinuria
thoracic rads: sternal &/or other nodes
abdominal U/S or other imaging: spleno/hepatomegaly, ln
cytology/bx: organs, lns
-relatively easy to dx cytologically
BM cytology/bx
PARR (PCR for antigen receptor rearrangement) if needed: used for tricky cases
-uniquely rearranged Ig & T-cell receptor gene sequences can be amplified & electrophoretically separated by size to detect a clonal population of lymphocytes
What is the staging method for canine lymphoma?
I: single node or lymphoid tissue in a single organ
II: involvement of many regional lymph nodes +/- tonsils
III: generalized lymph node involvement (both sides of diaphragm)
IV: liver and/or spleen involvement (+/- stage III)
V: manifestation in the blood and bone marrow involvement &/or other organ systems
(a) w/o systemic signs or (b) w/ systemic signs
What are the main prognostic variables for canine lymphoma?
clinical stage: higher stage shows generally worse outcome
substage: sick (b) is worse
immunophenotype: B is better than T & LGL
response to induction chemo: 80-90% of dogs feel significantly better w/in ~ 5 d.

histologic grade: low is best
hypercalcemia: worse outcome
other: prolonged steroid tx (worse: ↑ resistance), anatomic location (cutaneous, alimentary, intrathoracic worse)
What is the tx for canine lymphoma?
chemo +/- radiation
- many chemo protocols used (ex. CHOP)

best single agent against LSA is doxorubicin (adriamycin)
What is the px for canine lymphoma?
dogs w/ favorable prognostic indicators treated w/ multi-agent protocol including doxorubicin
-75-90% attain complete remission
-median remission: 6-8 mo.
-median survival: 10-14 mo. (B cell), 6-9 mo. (T cell)
-½ body radiation may lead to longer survival times

bad news: treatable, but essentially incurable w/ current tx schemes (perhaps BM transplant?)
feline lymphoma

a. etiology
b. signalment
a. viruses: FeLV, FSV, FIV, endogenous viruses, RD-114, FSFV
-FeLV/FIV (+) --> inc. risk of LSA
b. avg. age: 4.6-5.7 yrs (bimodal: 2 & 6 yrs)
-young cats: FeLV (+): w/ mediastinal or multicentric LSA
-old cats: FeLV (-) w/ alimentary LSA
What are the clinical forms of feline lymphoma?
alimentary: may have mesenteric lymphadenopathy, thickened bowel wall, stenosing lesions

hepatic, splenic: hepatomegaly, splenomegaly

mediastinal
-usually young, FeLV (+) cats
-signs: dyspnea, Horner’s syndrome, pleural effusion
-affects mediastinal space, sternal nodes, thymus

ocular: hypopyon, hyphema, anisocoria, anterior uveitis, retinitis

renal
-usually bilaterally enlarged, lumpy, painful kidneys
-signs: ARF
-40% relapse to CNS

cutaneous
-older cats
-signs: macules, scales, papules, may be solitary or multiple

nasal
-often solitary site: local dz can be cured w/ radiation alone, although systemic chemo is recommended
-signs: nasal d/c, facial deformity, sneezing
-ddx: rhinitis, polyps, other tumors (old cats)

CNS
-young cats
-T3-L3 lesions most common: extradural, spinal compressive lesions
-concurrent BM & renal involvement common
-signs: hind limb paresis or paralysis
-ddx: disc dz, viral neuropathy, trauma, discospondylitis
What are some possible findings on diagnostic tests in cats w/ lymphoma?
CBC: anemia, circulating blast cells
chem.: organ dysfunction
U/A: proteinuria
T4: concurrent problems in cats > 6 yo
FeLV, FIV tests; ELISA; IFA on BM if indicated
thoracic rads: mediastinal dz, other problems
abdominal U/S: mesenteric involvement, other dz
BM cytology/bx: neoplastic infiltration
sx?
What is the staging system for feline lymphoma?
I: single node or extranodal site
II: regional nodes; resectable GI
III: non-resectable abdominal or epidural tumor; generalized nodal involvement
IV: spleen or liver involvement
V: bone marrow involvement
(a) w/o systemic signs or (b) w/ systemic signs
What is the tx for feline lymphoma?
sx: for localized cutaneous tumor or obstructing GI tumor
-rarely used as a single tx

radiation: nasal, spinal, mediastinal sites
-LSA is very radioresponsive

chemo
-usually protocols include combinations of drugs: same as in dogs
What are prognostic indicators for feline lymphoma?
response to induction therapy, low vs. high grade

also location, stage, FeLV status
What is low grade lymphoma in cats?
o low grade LSA cells resemble normal or intermediate sized lymphocytes
o slower, indolent dz
o may occur in conjunction with or be the result of chronic IBD: neoplastic transformation of inflammatory lymphocytes?
o tx: leukeran (chlorambucil) & prednisone
o longer median survivals reported: ~18 months
What is the px for feline lymphoma?
o generally worse than in dogs
o can be very hard to manage

with chemo, ~2/3 of cats respond to treatment and go into remission; average survival is 7 months with a 25% 1 year survival
What is the signalment assoc. w/ canine mast cell tumors?
o mean age: 9 yo
o predisposed breeds: boxers (usually grade I), boston terriers, labs, beagles, schnauzers
What is the grading scheme for canine MCTs?
o based on bx: granulation, degree of invasion, degree of differentiation, # of mitoses

grade I: benign
-tx: sx

grade II: unpredictable (some are biologically aggressive)
-worse if ulcerated, alopecic, oozing, or arose quickly
-hard to tx

grade III: malignant
-tx: sx, +/- radiation, all get chemo

most are grade II (80-90%): much variation among pathologists concerning grade
What is involved in diagnostic staging & possible results for canine & feline MCTs?
o CBC/Chem
o abdominal U/S: check spleen, liver, abdominal ln’s
o 2 view thoracic rads
o FNA: may see few many cells but many eosinophils
o BM: only w/ grade III tumors or if cytopenias are present
o regional LN FNAs: ALWAYS check, even if not enlarged
-however, 25% of normal ln’s will contain some mast cells
o buffy coat: only w/ grade III tumors
What is the tx for canine MCTs?
o sx only: 2-3 cm margins optimal
-~50-66% of grade II MCT will NOT recur, even if residual microscopic dz is left behind

o chemo
-always for grade III
-any dog (no matter what grade) that develops multiple MCTs at once or over time is a candidate for systemic chemo

o radiation
-40-45Gy: 50% 1 yr. control rate
-combined w/ sx: 85% 2-yr control rate (grade I), 95% (grade II)

o sx + radiation is best option for distal limb, head, & perineal tumors where adequate margins cannot be achieved
What are prognostic indicators for canine MCTs?
histologic grade (most important), stage, location, mitotic index, growth rate, recurrence, systemic illness, age, breed, etc.
How is mitotic index related to overall survival for canine MCTs?
mitotic index (MI): direct correlation b’twn tumor grade & MI
-significant assoc. b’twn MI & rate of metastatic dz & overall survival: may help guide clinical decision making, esp. concerning grade II tumors

• grade II tumors w/ MI > 5: ~3 mo. survival
• grade II tumors w/ MI < 5: ~80 mo. survival
• grade III tumors w/ MI < 5 may have a good px
What are the 2 types of cutaneous feline mast cell tumors?
• mastocytic: histologically similar to canine dz
• histiocytic: rare
-often affects young to middle aged Siamese cats on the head or neck
-tumor appears similar to granulomatous inflammation, & can be misdiagnosed as such

most cutaneous MCTs are benign
Besides cutaneous, what are the forms of feline MCTs?
visceral
-> 50% of feline MCTs
-intestinal MCT is 3rd most common primary GI tumor in cats
-widespread dissemination & mets are common
-can see peripheral mastocytosis (~40%) & BM involvement (~23%)
-poor px: ~ 6 mo.

splenic
-either diffuse infiltration of spleen --> splenomegaly or nodular form
-may see significant peripheral mastocytosis & BM involvement
-splenectomy can lead to prolonged survival (12-19 mo.)
-spleen may look completely normal on U/S & still be completely effaced w/ mast cells
-ALWAYS aspirate spleen of any sick cat whose dx is unknown
What is the tx for feline MCTs?
complete excision of well-differentiated mastocytic MCTs normally curative
-some cats can develop multiple tumors at same time or sequentially

biologic behavior of poorly differentiated MCTs & histiocytic MCTs is less clear

histiocytic variant in young cats usually spontaneously regresses
What are some general characteristics of canine soft tissue sarcomas?
-most tumors are solitary & malignant
-appear as pseudoencapsulated masses that are locally invasive
-local recurrence common after conservative surgical excision
-tend to metastasize hematogenously: regional LN mets uncommon (except synovial cell tumors)
-bulky tumors (> 5 cm) have poor response to chemo &/or radiation
What is the grading system for canine soft tissue sarcomas?
points assigned based on differentiation, mitoses, necrosis

grade I: cumulative score ≤ 4
grade II: cumulative score of 5-6
grade III: cumulative score ≥ 7
grade is predictive of metastasis
-grade I: 10%, grade II: 20%, grade III: 50%
What is the staging/diagnostic workup for canine soft tissue sarcomas?
CBC, Chem
3 view thoracic rads
abdominal U/S
FNAs to R/O round cell tumors, cysts, abscess
bx: required for histologic dx & grading
CT/MRI: used to determine extent &/or invasiveness
-CT: best “bang for the buck”
What is the tx for canine soft tissue sarcomas?
sx alone: en bloc w/ 2-3 cm lateral margins & 1 facial plane deep

radiation only
-generally considered palliative

sx + radiation
-mainly for distal limb tumors or other areas where adequate margins can’t be achieved
-~75% 3 & 5 yr. survivals

chemo
-rarely indicated for grade I & II tumors unless there is a suspicion of metastasis
-always for grade III tumors d/t high metastatic rate
-using chemo to kill residual microscopic dz remains controversial
-rational 1st choice: doxorubicin
What are the main prognostic indicators for canine soft tissue sarcomas?
size: > 5 cm worse than < 5 cm
MI: high grade (> 20 mitoses/10 HPF) worse
location
-superficial/extremities better
-oral: ↓ median survival (1.5 yrs. vs. 6.3 yrs)
fixation: mobile better, fixed worse
clean margins better
What is the signalment assoc. w/ feline soft tissue sarcomas?
young cats: head/neck tumors usually assoc. w/ FeLV infection (incurable)

old cats: head/trunk tumors not assoc. w/ FelV (can cure w/ sx &/or radiation)
What is the pathogenesis of feline injection associated sarcomas?
typically arise at sites of repeated vaccination (esp. RV & FeLV), but have also been reported at sites of a wide variety of other injections ↓

vaccination of cats w/ FeLV & rabies virus vaccines ↑ risk of vaccine associated sarcoma 2-5 fold

assoc. w/ killed vaccine products given SQ

role of adjuvants?

fibroblastic or myofibroblastic response --> malignant transformation
What is the grading system for feline injection assoc. sarcomas?
based on mitotic index, differentiation, & necrosis

I: 25%, II: 48%, III: 27%

differentiating from non-vaccine associated sarcomas
-multinucleated giant cells in grades II & III
-most have peritumoral lymphocytic inflammation
What is the clinical behavior of feline injection assoc. sarcomas?
• rapid growth, locally invasive (infiltrative)
• regrowth after inadequate surgical excision
• 10-25% metastasize: lungs & other sites
What is the diagnostic workup/staging for feline injection assoc. sarcomas?
• CBC, Chem, U/A
• FNA, incisional bx
• thoracic rads
• abdominal U/S
• CT or MRI: recommended to determine extent & invasiveness of tumor BEFORE sx is attempted
What is the tx for feline injection assoc. sarcomas?
• sx: en bloc resection w/ 3 cm margins
-tx of choice when adequate margins can be achieved
-scapulectomy, removal of spinous processes, amputation, hemipelvectomy
-histologic examination of margins very important
*complete excision: > 16 mo. survival
*incomplete excision: 4-9 mo. survival

radiation: not much ↑ in survival over sx
-b/c of need for very wide excision, many cats are optimally treated w/ radiation therapy prior to surgical removal

• chemotherapy: minimal data
-drug of choice: doxorubicin
What are the characteristics of post-vaccinal rxns in cats?
~12% of cats vaccinated will develop post-vaccinal rxns
can reach 6 cm in diameter
rxns resolve w/in 30-90 d.
What is the px for feline injection assoc. sarcomas?
staging & dx, radiation, sx, chemo: $8-10K w/ a hopeful life expectancy of ~1.5 yrs
Under what circumstances should vaccine site rxns in cats be excised or biopsied?
excise or bx vaccine site rxns that persist > 3 mo. are > 2 cm. diameter, or ↑ in size 1 mo. after vaccination
What are the 5 most common oropharyngeal tumors in dogs?
malignant melanoma
fibrosarcoma
SCC
ameloblastoma
osteosarcoma
What are the 3 most common oropharyngeal tumors in cats?
SCC
fibrosarcoma
What are the clinical signs assoc. w/ oropharyngeal neoplasia?
signs are highly variable
-often found incidentally by owners or DVM during dental prophylaxis when pet has no clinical signs
-caudal tumors are harder to see, therefore these are usually not noticed until signs such as ptyalism, halitosis, sneezing, bloody saliva, wt. loss, or dysphagia are seen
-feline sub-lingual SCC are almost never found before it is essentially to large to effectively tx
What is the tx for oropharyngeal neoplasia?
essentially a surgical dz: used to gain local &/or regional (LN) control of tumor
-surgical options include “en bloc”, maxillectomy, or mandibulectomy
-adequate margins are always an issue d/t location

if margins are not adequate: post-op definitive radiation
cataracts)
-ameloblastomas (epulides) are exquisitively sensitive to radiation (95% cure rate) w/o prior cytoreductive surgery!!
-feline oral SCC also extremely sensitive to radiation, but response is typically very short-live

chemo in combo w/ sx &/or radiation may be useful in tx of oropharyngeal neoplasms known to metastasize
What are some prognostic factors for canine oropharyngeal tumors?
•smaller, more rostral tumors have better px
•radiation can be used to gain local control if sx did not
•chemo indicated if metastatic: tonsilar SCC, oral melanoma, OSA
canine oral SCC
a. clinical behavior
b. tx
c. px
a. •locally invasive neoplasm w/ ability to invade underlying bone
•distant mets are rare
•caudal tumors are harder to detect and are biologically more aggressive
b. wide surgical excision & radiation both provide good local control of 1º tumor
c. poor to good
canine oral malignant melanoma
a. clinical behavior
b. tx
c. px
a. buccal mucosa most common site
-common regional LN and distant LN mets: most common cause of tx failure
-only 2/3 are pigmented/ulcerated
b. multimodal therapy of sx, radiation, & chemo may improve dz free interval & long term survival
c. poor to fair
canine oral fibrosarcoma

a. clinical behavior
b. tx
c. px
a. gingiva most common site
-mets rare
-locally extensive: common bone involvement --> ↑ local recurrence
b. best treated w/ combo of sx & radiation: not considered very radiosensitive
c. poor to fair
canine oral osteosarcoma

a. clinical behavior
b. tx
a. locally aggressive & can affect any bone: metastatic at dx
-intra-medullary mandibular tumors tend to be biologically benign: sx w/ no chemo
b. always follow sx w/ chemo, unless mandibular in origin
canine epulides

a. clinical behavior
b. 3 types
c. tx
d. dx dilemma
e. px
a. usually occur in younger dogs & often involve rostral mandible
-do NOT metastasize
b. acanthomatous, ossifying, fibromatous
-acanthomatous tends to invade underlying bone more aggressively
c. all are 100% curable w/ sx & 95% curable w/ definitive radiation
- b/c of high incidence of local recurrence after simple surgical excision, wide excision (partial maxillectomy or mandibulectomy) has been recommended
d. can be easily confused with SCC on histopath: be careful!
e. excellent
feline oral SCC

a. clinical behavior
b. tx
c. px
a. usually arise from gingiva & are often ulcerated
-rarely involve regional LN or have distant mets
-locally aggressive: bone involvement common
b. poor response to sx & radiation
c. very poor: local dz is usually the cause of death
feline oral fibrosarcoma

a. clinical behavior
b. tx
c. px
a. gingiva: most common site
-occasional distant mets, but rare regional LN mets
-bone involvement common
b. poor radiation response, cats generally don’t tolerate significant oral sx as well as dogs
c. fair
cyclophosphamide

a. mechanism of action
b. adverse effects
a. alkylating agent: alkylates bases of DNA --> cross-links bases of DNA --> cessation of DNA synthesis --> cell death

b. dose dependent BM suppression --> neutropenia, nausea, V/D, sterile hemorrhagic cystitis,
cisplatin

a. mechanism of action
b. adverse effects
a. platinum complex: cross links DNA w/ platinum molecule --> inhibits DNA synthesis

b. nephrotoxicity (dose limiting effect), V/D, extremely toxic to cats (resp. effects), mild myelosuppression
vincristine

a. mechanism of action
b. adverse effects
a. vinca alkaloid: "spindle poison"
binds to tubulin proteins which form microtubules responsible for chromosome migration during mitosis --> blocks polymerization of microtubles --> arrests mitosis in metaphase

b. tissue sloughing if given perivascularly, peripheral neuropathy
doxorubicin

a. mechanism of action
b. adverse effects
a. anthracycline AB: inhibits topoisomerase-II dependent DNA synthesis, intercalates b’twn DNA base pairs --> cell death by blocking RNA & protein synthesis

b. BM suppression, cardiotoxicity (dose limiting effect), anorexia, V/D, hypersensitivity rxns
What are some effects of glucocorticoids used for cancer tx?
-cytotoxic to malignant lymphocytes
-anti-emetic (dexamethasone)
-↓ inflammation assoc. w/ cancer
-↓ TNF synthesis
-improves appetite
How is the cell cycle related to cancer development?
all cancers develop d/t perturbations in cell cycle regulatory process

the more adverse the conditions, the more variable the cycling times & the longer the G1 interval

under severe conditions, many cells will move into G0 phase from G1 phase