Flashcards in 03a: Colon Deck (62)
Lifetime risk of colon cancer is (X)%
X = 5
Lifetime risk of colon adenoma is (X)%
X = 60
Which behavioral trends have led to the (increase/decrease) in colon cancer (incidence/mortality)?
1. Decrease smoking
2. Improved diet/exercise
T/F: an emigrating population acquires the colon cancer risk of the new environment
True - variation in geographic incidence may be related to diet
List the modifiable factors that increase risk for colorectal cancer
1. Red and processed meat intake
3. Smoking and EtOH
4. DM II
List the modifiable factors that decrease risk for colorectal cancer
1. Physical activity
3. Hormone replacement Rx
4. Dairy/Ca, folate
T/F: about 35-40% of colorectal cancer cases are sporadic
False - 75%
Classic Familial Adenomatous Polyposis: risk of colorectal cancer approaches 100% by age (X). Caused by (Y) gene mutation.
X = 40
Y = APC (chrom 5)
Patient is 25 years old with multiple (over 100) colorectal adenomas. Which genetic disease is he likely to have? What’s the mode of inheritance?
Classic FAP; autosomal dominant
(FAP/AFAP) presents with adenomas that are predominantly right-sided. What’s the mean age at which these polyps are seen?
T/F: both FAP and AFAP are cause by genetic mutation in APC
MUTYH-associated polyposis mimics (X) disease phenotypically but has mutation in (Y)
X = FAP
Y = MUTYH (base-excision repair)
Hereditary Nonpolyposis Colorectal Cancer (HNPCC) aka (X) Syndrome: which age of onset? And predominance of cancer at which site?
X = Lynch
40 yo or under
T/F: HNPCC results in multiple primary cancers (colorectal and extracolonic).
HNPCC: mutation in which genes?
DNA mismatch repair (MLH1,2, MSH6, PMS2)
List the two sequences of natural progression to colorectal cancer. What percent of CRC has followed each of these paths?
1. Adenoma-Carcinoma sequence (80%)
2. Serrated Adenoma Path (20%)
How long (timeline) is the Adenoma-Carcinoma sequence for colorectal cancer? List the steps
Small adenoma, large adenoma, HG dysplasia, invasive cancer, metastasis
How long (timeline) is the Serrated Adenoma pathway for colorectal cancer? List the steps
Microvesicular Hyperplasia, sessile/serrated adenoma/polyp, serrated adenoma, serrated cancer, metastasis
Individuals with one first-degree relative affected by CRC before age 60 have an (X)-fold increased lifetime risk of developing CRC. The risk applies/begins when they’re (older/younger/same age) as relative.
X = 2-3
Younger (10 y younger)
List the Amsterdam II criteria for (X) disease.
X = HNPCC
1. 3+ relatives with HNPCC associated cancer
2. 2+ generations of CRC
3. 1+ case before age 50
T/F: 95% of colorectal cancers are adenocarcinomas
Diagnostic method of choice for CRC
How might a CBC be helpful in diagnosing or verifying CRC?
Fe deficiency anemia (Sx of CRC in cecum)
CRC: best imaging study for detecting intra-abdominal spread of disease
CRC: Endoscopic ultrasound useful in assessing
depth of invasion and local lymph node status for rectal cancers
Carcinoembryonic antigen (CEA) serum levels can be used to monitor recurrence of (X) cancer after curative surgery
X = colorectal
T/F: Chemotherapy for advanced colorectal cancer (Stage IV) has proven incredibly successful.
False - v disappointing
Which type of therapy is recommended for Dukes’ C (node-positive) colon cancers?
Chemo (alone or with radiation) given post-op after curative resection
Which type of therapy is recommended for Dukes’ B2 and C rectal cancers?
1. Curative surgery
2. Chemo with high dose pre- and/or post-op radiation