Gastrointestinal Pathology - Colon Flashcards
When is the peak incidence for colorectal carcinoma? What two ways does it arise? How do you screen for it? What type of infection does it put you at risk? How do you stage it? What type of marker would you use?
Peak incidence is 60-70 years old. Arises from adenoma-carcinoma sequence or molecular pathway via Microsatellite instability. Screening is via colonoscopy and fecal occult blood testing. Associated with increased risk for Streptococcus bovis endocarditis. Staging is via T - depth of invasion ; N- spread to regional lymph node; M - metastasis. CEA is tumor marker used for assessment of treatment response and detecting recurrence BUT NOT USEFUL FOR SCREENING
A 68 year old retired school teacher comes to your GI clinic complaining that her stool looks different that usual. It appears narrower than usual. It is also redder than usual. What does she have and Where does she have pain? What characteristic pattern does her lesion grow with?
She has left sided colorectal carcinoma with pain on the lower left quadrant. Presents with decrease in stool caliber and blood streaked stool. Characteristic napkin ring lesion.
A 68 year old retired school teacher comes to your GI clinic complaining that her stool looks different that usual. What does she have and What else would she present with?
She has right sided carcinoma that usually grows as a raised lesion. She would also present with iron deficiency anemia (occult bleeding) and vague pain.
An older adult with iron deficiency has what kind of carcinoma?
Colorectal carcinoma until proven otherwise.
What does hereditary nonpolyposis colorectal carcinoma arise from? What does it increase the risk of? Which side does it localize?
Due to inherited mutations of DNA mismatch repair repair enzymes. Arises de novo not from adenomatous polyp at a relatively early age. Usually right sided. Increased risk for colorectal, ovarian and endometrial cancer.
A 34 year old lawyer presents to the derm office complaining of freckle like spots on her lips. Upon physical exam, you notice that they are also in her oral mucosa and her genitals. What does she have? What would you see if you could examine her GI tract? How is it inherited? What is she at increased risk of?
She has Peutz-Jeghers syndrome which are benign hamartomatous polyps throughout the GI tract and hyper pigmentation. Autosomal dominant disorder. She is at increased risk for colorectal, breast and gynecological cancer.
A 3 year old kid is brought in to your peds clinic. His mom is worried because she found a bleeding polyp in his recital area. What is this? How does it present? Where else could similar polyps arise? What does it increase the risk of?
He has juvenile poly which is a sporadic and hamartomatous benign polyp that arises in children less than 5 yo. JP is characterized by multiple juvenile polyps in stomach and colon. Increases risk of progression to carcinoma when number of polyps is large.
You are a pathologist working in a lab and you see a biopsy of a colon with 100s of polyps. What is this disease and What is the inheritance pattern ? What does it cause and How is it treated?
This is Familial Adenomatous Polyposis which is an autosomal dominant disorder due to inherited APC mutation on chromosome 5. Increases propensity to develop adenomatous polyps throughout colon and rectum, Colon and rectum are prophylactically removed otherwise all patients develop carcinoma by 40 years of age.
What is FAP with fibromatosis and osteoma?
Gardner Syndrome
What is FAP with CNS tumors?
Turcot Syndrome
What is fibromatosis and where does it arise?
It is a non-neoplastic proliferation of fibroblasts. It arises in retroperitoneum (desmoid) and locally destroys tissue
If you see a non neoplastic proliferation of fibroblasts and a benign tumor of bone arising from the skull in a patient with 100s of colonic polyps, what syndrome do they have?
Gardner Syndrome
What are colonic polyps and what are the most common types?
Raised protrusions of colonic mucosa. Common types are hyperplastic and adenomatous polyps.
What causes hyperplastic polyps? What do you see on histology? where do they arise and are they malignant?
They are due to hyperplasia of glands. Classically see a serrated appearance on microscopy. Usually arise in the left colon (rectosigmoid). Benign with no malignant potential.
What causes adenomatous polyps? Are they benign?
Due to neoplastic proliferation of glands. Benign, but premalignant. May progress to adenocarcinoma via the adenoma-carcinoma sequence.
