Colorectal Cancer Flashcards
risk factors for developing colorectal cancer
increases with age more common in industrialized world - western diet? diet high in fats, red meats inadequate intake of fiber fruits and vegetables family history alcohol intake smoking obesity inflammatory bowel disease
rectal cancer is defined as
arising below peritoneal refection of <12cm from the anal verge
colon cancer is more common than
rectal cancer
most common colorectal cancer
sigmoid colon/rectum
pathophys
colorectal adenocarcinomas remain superficial for a long time and slowly invade the deeper layers of the intestinal wall
extension through the bowel wall into the pericolonic fat
more distant spread can take place to the liver and lungs
signs and symptoms
changes in bowel habits diarrhea or constipation blood in stool narrow stools ab and gas pain weight loss tenesmus(inclination to evacuate the bowels)
why should people get screened
survival rate much better in the beginning
very bad by stage 4
decreases the risk of dying
screening tests
stool blood guaiac test to detect blood in stools sigmoidoscopy barium enema colonoscopy carcinoembryonic antigen
screening is effective because
we can detect precancerous early stage cancers in people who dont show symptoms
can confirm and more easily treat cancer in early stages
who should be tested and how often
> 50 evaluated annually with fecal occult blood testing unless high risk
primary curative procedure for stages 1-3
surgery
resection of the bowel
why do we do radiation to tumor bed and surgically inaccessible areas of tissue
to decrease local recurence
can be used for lessening symptoms
stage 1
local diseas eno invasion of muscular mucosa
stage 2
invasion of muscular mucosa
stage 3
lymph node involvment
stage 4
metastatic disease
application of chemo in colorectal cancer
adjuvant after surgery in stage 2 and 3
primary therapy of metastatic colon and rectal cancers
most commonly used agent in colorectal cancer
fluorouracil
fluorouracil toxicity based on type of admin
bolus - grade 3 and 4 hematological toxicity
continuous infusion - hand foot syndrome
what is hand foot syndrome
paiful reddening of skin
should report any changes to palms and soles asap
prevent by moisturizing and avoiding heat and friction
treatment of hand foot syndrome
topical anesthetics
cold
oral analgesic
FU use
adjuvant and metastatic
irinotecan mechanism and use
top 1 inhibitor
metastatic or FU resistance
first line for metastatic colorectal in combo with FU and leucovorin
irinotecan problem
diarrhea early and late onset
oxaliplatin class and use
third gen platinum analog
adjuvant and metastatic
oxaliplatin SE
peripheral neuropathy
laryngeal spasm
cold intolerance
raltitrexed class and use
thymidilate synthetase inhibitor
metatstatic
capecitabine use and class
fluoropyrimdine - can be delivered at hom e
adjuvant and metastatic
capecitabine metabolized to
fluorouracil
investigated in combos as an alternative to infusional FU
dosing of capecitabine
twice daily oral for 14 days then 7 day rest period
capecitabine AE
palmar plantar erythrodysesthesiia (hand foot)
diarrhea
stomatitis
bevacizumab class and use
monoclonal antibody directed against vascular endothelial growth factor
metastatic not adjuvant
use of vascular endothelial growth factor
promotes growth of vascular endothelial cells derived from arteries and veins
promotes endothelial cell survival
bevacizumab toxicity
perforation
hypertension
bleeding
thromboembolism
mechanism of cetuximab
chimeric monoclonal antibody directed at cancer cells overexpressing the epidermal growth factor receptor frequently seen in colorectal cancers
cetuximab AE
weakness, malaise, fever, headache, acneiform rash
what is panitumumab and its use
fully human EGFR antibody
survival benefit late line therapy***
disease free survival as a primary end point
allows to make a quicker decision of efficacy so drug development time can be shortened and better therapy available to patients quicker
is adjuvant therapy for stage 2 required
still unknown
stage 2 colon cancer who should be treat (adjuvantly??)
no molecular low risk factors <60yoa less than 9 nodes removed T4 tumors perforation
stage 3 colon cancer standard adjuvant
6 months of oxaliplatin based therapy
stage 2 colon cancer treatment
6 months capecitabine
adjuvant in rectal
during radiation fluorouracil 200mg/m2/day
preoperative fluorouracil with radiation
4 months of post op oxaliplatin based therapy
FU mechanism
pyrimidine antagonist
how leucovorin increased survival with FU
enhances binding of FdUMP to target enzyme
route to improve survival and decrease toxicity with FU
continuous infusion
irinotecan vs oxaliplatin
same efficacy choice depends on toxicity
irinotecan: no neuropathy, dose reduction for hepatic dysfunction
oxaliplatin: less alopecia, mucositis, and nausea, safer in hepatic dysfunction
risk factor for oxaplatin persistent neurotoxicity
total cumulative dose
all patients will experience sensory neuropathy after 4 cycles
acute oxaliplatin neurotoxicity
in 2-48 hrs
rapid and complete recovery
persistent oxaliplatin neurotoxicity
affects fingertips and toes then hands and feet
persists between cycles
increases in duration and intensity
slow recovery
