SFP: GI tumors Flashcards
What are polyps?
Mass that protrudes into the lumen of the gut
What is a hamartoma?
Disorganized tissue indigenous to a site; normal tissue with irregular organization
What is a hyperplastic polyp?
A small, benign polyp caused by delayed shedding of the epithelium
What is the gross appearance of hyperplastic polyps?
Serrated epithelial appearance
Describe histology of hyperplastic polyps.
Normal cells, just an increased number of the cells.
What are juvenile polyps?
Benign polyps; Hamartomatous malformation, usually coming in singles. They often happen before the age of 5 and may present with bleeding
Describe gross appearance of juvenile polyps.
Round and smooth with a stalk
Describe the histology of juvenile polyps.
They have cystic spaces, eroded surface epithelium, architectural distortion but normal cells/aspects
What are peutz-jeghers polyps?
Benign hamartomous polyps throughout the GI tract associated with peutz-jegher syndrome.
Describe the gross appearance of peutz-jeghers polyps.
Melanotic mucosal and cutaneous pigmentation
Describe the histology of peutz-jeghers polyps.
Irregular but present epithelium with dilated spaces
Describe adenomatous polyps.
Neoplastic/dysplastic polyps that don’t have metastatic potential, but do have the potential to become adenocarcinoma.
What are the types of adenomatous polyps?
Tubular and villous
Compare histology of villous and tubular adenomas.
Villous have finger-like projections, while tubular have circular glands and have more of a crypt component. Both have enlarged nuclei and less cytoplasm.
What is familial polyposis coli?
Genetic syndrome causing a bunch of adenomas throughout the colon
What is Gardner’s syndrome?
Genetic syndrome causing adenomas throughout the colon as well as hamartomas in the stomach
What is Crail’s syndrome?
Genetic syndrome causing adenomas throughout the colon as well as CNS tumors
What is HNPCC?
A mutation in DNA mismatch repair gene causes polyps that carry risk of becoming cancer
What are risk factors of adenocarcinoma of colon and rectum?
Diet, age, sex, pre-existing conditions
Describe the adenoma to carcinoma pathway.
- Inherited or acquired mutations of tumor suppressor genes exist 2. Normal alleles become inactivated via methylation 3. Adenomas form due to protooncogene mutation and loss of additional cancer suppressor genes 4. Mutations and chromosomal alterations lead to progression to carcinoma
Describe the mismatch repair pathway for carcinoma development.
- Inherited or acquired mutations of mismatch repair genes exist 2. Alteration of a second allele causes sessile serrated adenoma 3. More accumulated mutations lead to carcinoma
Describe right colon lesions.
Less likely to be obstructive and are exophytic masses
Describe left colon lesions.
Tend to be annular/encirculating and are more likely to cause obstruction
Describe histology of adenocarcinoma.
Irregular glands, production of mucin, potentially involves necrosis
What is the clinical presentation of colorectal cancer?
Pain, change in bowel habits, iron deficiency anemia if there is bleeding
What tumors are seen in the appendix?
Neuroendocrine, adenocarcinoma, mucocele
What is a mucocele lesion?
Dilated appendix with mucin in it; may be secondary to a bunch of stuff like hyperplasia, cystadenoma, low grade mucinous neoplasms, etc
