Week 3: colon polyps and cancer Flashcards
Describe colon epithelium histology
columnar cells that make up the glands
Describe colon lamina propria histology
supportive connective tissue which harbors the glands
Describe colon muscularis mucosa histology
this superficial layer of smooth muscle
Describe colon submucosa histology
connective tissue
Describe colon muscularis propria histology
Thick outer layer of smooth muscle responsible for peristalsis
Describe colon serosa histology
thin outer lining of mesothelial cells
Intestine epithelial crypts
Why are the specific layers of the colon important as they pertain to cancer?
What is this?
Polyp
What is the difference?
Describe tubulovillous adenoma
- has at least low grade dysplasia
- can progress to carcinoma
Describe the meaning of hyperplastic
- is essentially benign
- will not progress to carcinoma
Describe the meaning of serrated
- Histologic deceptive term
- Glands of polyps have undulations (like a serrated knife edge)
- Certain types can progress to carcinoma (more on this later)
What are the most common colon polyps
What is this?
Hyperplastic colon polyp on the right
Describe hyperplastic colon polyps
Describe the histologic features of a hyperplastic colon polyp
- surface has irregular tufting of epithelial cells
- superficial serrated architecture and absence of atypia
Describe Adenomas properties & screening policies
Adenomas Gross histology
3 to 10 mm, pedunculated or sessile, dark red surface that looks velvety or like a raspberry
Describe Adenomas histology
- epithelium is dysplastic: nucleui of surface epithelial cells are hyperchromatic, elongated and stratified, reduction of goblet cells
- Tubular rounded glands
- Villous: slender villi
- Tubulovillous: mixed
What is the most common preneoplastic polyp screened for?
Tubular adenoma
What is this?
What is this?
TVA (Tubulovillous adenoma)
What are these?
Describe Sessile Serrated Adenomas histology
Most common location of Sessile Serrated adenomas
precancerous polyps usually found in the right colon
Sessile Serrated Adenomas properties
What are these?
Compare and contrast TA, SSA and HP
What are some of the features of a polyp with a higher risk of progressing to cancer?
Screening intervals are based on?
What is a hamartoma?
An abnormal growth of tissue elements normally found at that site [ie normal tissue for that site just disorganized]
Describe what a hamartomatous polyp is
Which of the following polyps are dysplastic by definition?
- Tubular adenoma
- Hyperplastic polyp
- Sessile Serrated adenoma
- Hamartomatous polyp
Describe the risk for adenocarcinoma
Describe the prevalence of adenocarcinoma
Describe the various locations of adenocarcinoma and location-specific signs and symptoms
Describe the histological features of adenocarcinoma
How is adenocarcinoma staged?
TNM staging
T = depth
N = nodes
M = distant mets (most common is liver)
What are these?
Adenocarcinoma
Describe the molecular pathways of colon carcinogenesis
Adenoma-Carcinoma pathway
Adenoma-Carcinoma pathway figure
Serrated pathway AKA
Serrated pathway figure
Microsatellite instability?
MSI example
Overview of microsatellite instability
Summary of sporadic cancer pathways
Hereditary non-hamartomatous polyposis cancer syndromes
- Familial adenomatous polyposis
- Lynch syndrome
Hereditary hamartomatous polyposis cancer syndromes
- Peutz-Jeghers Syndrome
- Juvenile Polyposis Syndrome
Familal Adenomatous Polyposis
FAP gross histology
Describe Lynch Syndrome
MSI SSAs not TAs?
Confusion
Summary of LS vs Sporadic Serrated pathway
Question
Got like 10 questions at the end of this lecture was hungover and ran out of fucks to give
Peutz-Jeghers Syndrome
Peutz-Jeghers Polyp
Peutz-Jeghers increased risks
Average age of cancer diagnosis with Peutz-Jeghers
46
Juvenile Polyposis syndrome
Juvenile Polyp
Juvenile Polyposis syndrome juvenile reference and location
