colorectal cancer

Question 1

risk factors for colorectal cancer

Answer 1

age (>50)
Ashkenazi Jewish highest risk, African American
History of bowel disease/polyps (UC, Crohn’s)
Diet (high fat, low fiber, alcohol, low antioxidant/calcium/Vitamin D)
obesity, physical inactivity
diabetes
HNPCC, FAP

Question 2

inherited conditions giving you high risk of colorectal cancer

Answer 2

1. Hereditary non-polyposis colorectal cancer (HNPCC): 80% risk of developing colon cancer by age 44
2. Familial adenomatous polyposis (FAP): 100% risk of developing colon cancer (average age 39)

Question 3

specific screening guidelines for colorectal cancer

Answer 3

beginning at age 45 (earlier if high risk)
-yearly blood stool test (FOBT) or fecal immunochemical test (FIT) AND one of the following: flexible sigmoidoscopy, double contrast barium enema, CT colonography every 5 years, or colonoscopy every 10 years

Question 4

when do you screen at a younger age?

Answer 4

family history of HNPCC: age 30
family history of FAP: puberty

UC or Crohn’s: 8 years after onset of pancolitis

Colorectal cancer or polyps in a 1st degree relative: age 40 or 10 years before youngest case in family, whichever is earlier

personal history of adenoma w/ polypectomy: 3 years after initial

Question 5

importance of KRAS mutational status

Answer 5

if wild type: may respond to anti-EGFR therapy
if mutant: will be unresponsive, and worse prognosis

Question 6

KRAS vs BRAF implications in therapy?

Answer 6

KRAS mutation= resistance to EGFR inhibitors
BRAF mutation= resistance to chemotherapy

Question 7

1st line combo therapy for colorectal cancer

Answer 7

FOLFOX: fluorouracil, leucovorin, oxaliplatin

Question 8

agents that target EGFR
what is the CRC marker?

Answer 8

cetuximab
panitumumab
CRC marker is KRAS wild-type

Question 9

agents that target VEGF

Answer 9

bevacizumab
ramucirumab
Ziv-Aflibercept (a decoy receptor)

Question 10

agents that target PD1 with CRC marker microsatellite instability high (MSI-h)

Answer 10

pembrolizumab
nivolumab

Question 11

agents that target CTLA-4
what is the CRC marker?

Answer 11

ipilimumab
CRC marker is microsatellite instability high (MSI-h)

Question 12

agents that target PD1 with CRC marker deficient mismatch repair (dMMR)

Answer 12

dostarlimab

Question 13

agent that is a VEGF receptor inhibitor

Answer 13

regorafenib

Question 14

agent that is a BRAF inhibitor
what is the CRC marker?

Answer 14

encorafenib
CRC marker is BRAF V600E mutation

Question 15

agents that target HER2 and what is the CRC marker

Answer 15

trastuzumab
lapatinib
tucatinib
pertuzumab
CRC marker is HER2 positive tumors