Colorectal Cancer Flashcards
Mutation and inheritance in familial adenomatous polyposis
AD mutation in APC gene
Who should be tested for HNPCC/Lynch syndrome?
All CRC patients, regardless of stage or age
How do you screen for HNPCC?
Mismatch repair protein ICH or MSI testing (PCR)
What genes are implicated in HNPCC? (4)
MSH2
MSH6
MLH1
PMS2
What is difference about MLH1 mutations compared to other mutations seen in MMR-deficient CRC?
MLH1 mutation can be sporadic. If it is seen in MLH1 hypermethylation or BRAF mutation, then it is sporadic, not germline
At what age should CRC screening begin?
45
T stage in colorectal cancer
T1: submucosal invasion
T2: Invasion muscularis propria
T3: Invades through muscularis propria or subseroa
T4: Directly invades other structures
N stage in CRC
N1: 1-3 LNs
N2: 4+ LNs
Adjuvant treatment for intermediate risk stage III CRC
3 months CAPEOX
6 months FOLFOX
Adjuvant treatment for high risk stage II CRC?
3 months CAPEOX
6 months FOLFOX
6 months 5-FU or Cape
What designates someone as high risk Stage III?
T4 and/or N2
Adjuvant treatment for high-risk stage III CRC? (2)
6 months CAPEOX
6 months FOLFOX
Adjuvant Treatment for low-risk stage III CRC
3 months CAPEOX
3-6 months FOLFOX
if can’t tolerate doublet, 6 months 5-FU or Cape
What classifies someone as high risk stage II CRC (6)
T4
Less than 12 LNs
Obstruction/perforation
LVI
PNI
Poor differentiation
Adjuvant treatment for a patient with stage II MSI-H/MMR-D CRC?
No adjuvant chemotherapy, unless high risk features
For stage T3Nx rectal cancer, what is the preferred treatment paradigm?
Preoperative chemoradiation with 5-FU, then surgery, then adjuvant chemotherapy with CAPEOX or FOLFOX maybe
What is the benefit of preoperative chemoRT compared to postoperative RT in rectal cancer?
Less toxic, less local recurrence, more sphincter sparing surgeries, no change in distant mets
For rectal cancer, what is the difference in short course preoperative radiation compared to chemoRT?
short course radiation had more locoregional recurrence
In patients with upper rectal cancer who wish to avoid radiation, what is their option?
Preoperative FOLFOX can allow people to avoid chemoRT 90% of the time
Management of T1N0 rectal cancer
Local transanal excision