Neoplasms of the Lower GI Tract

Question 1

polyps have two types of gross architecture, what are they ?

Answer 1

sessile vs peduculated (contain stalk)

Question 2

what are the 2 types of histologic architecture for adenomas

Answer 2

Tubular short (crypts) vs villious (long finger like projections)

Question 3

list the Non-Neoplastic Polyps

Answer 3

Inflammatory Polyps (Benign)
Hamartomatous Polyps (increase risk of carcinoma in other organs)
Hyperplastic Polyps (Benign)

Question 4

Inflammatory polyps Often present with ______,
Often due to __________.
Cycles of injury and healing result in “polyp” formation = inflamed colonic mucosa with ulceration/erosion, epithelial hyperplasia

Answer 4

bleeding,
mucosal prolapse (very common in the rectum)

Question 5

an extraintestinal manifestation Peutz-Jeghers syndrome is ________

Answer 5

Mucocutaneous pigmented lesions

Question 6

what syndromes are associated with Hamartomatous Polyps

Answer 6

Juvenile
Peutz-Jeghers
Cowden,
Cronkhite-Canada

Question 7

an extra-intestinal manifestation of juvenile syndrome is ______

Answer 7

Pulmonary arteriovenous malformations, digital clubbing

Question 8

an extra-intestinal manifestation of Cowden syndrome is ______

Answer 8

Benign skin tumors, benign and malignant thyroid and breast lesions

Question 9

what are extra-intestinal manifestations of Cronkite-canada syndrome

Answer 9

Nail atrophy, 
hair loss, 
abnormal skin pigmentation, 
cachexia (A general state of ill health involving marked weight loss and muscle loss.), 
anemia

Question 10

Sessile Serrated Polyps/Adenoma are pre-malignant whereas _____ are not

Answer 10

Hyperplastic Polyps

Question 11

Hyperplastic Polyp are Predominantly on the ____ of the colon whereas Serrated Polyps/Adenoma are on the ______of the colon (proximal).

Answer 11

left side,

Right side

Question 12

what are strong risk factor associated with Colorectal carcinoma

Answer 12

advanced age,
country of birth
FAP/HNPCC
long standing ulcerative colitis

Question 13

what are the 4 main pathways to colorectal cancer?

Answer 13

1) WNT/APC/beta-catenin – classical adenoma-carcinoma sequence
2) K-Ras/MAP kinase/PI3 kinase signaling pathways—activating mutations
3) Microsatellite Instability – defects in mismatch repair proteins
4) epigenetic events such as methylation-induced gene silencing…enhances progression along these pathways

Question 14

what is Familial Adenomatous Polyposis (FAP)

Answer 14

Autosomal dominant germline mutation of APC gene

Question 15

cetuximab can be used in treatment of CRC only if the colon tumor is ________

Answer 15

KRAS wild-type

Question 16

what are the 3 Most important prognostic factors in CRC

Answer 16

Depth of invasion
Presence or absence of lymph node metastasis
Distant metastasis

Question 17

Colon cancer most commonly metastasizes to the ________

Answer 17

Liver