Pathology of the small intestine II Flashcards
what is the major cancer of the GI tract?
adenocarcinoma
familial polyposis coli increases the risk of progression to what disease?
adenoma
which condition grows in a napkin ring formation?
small bowel adenocarcinoma
what is the most common type of polyp?
hyperplastic
what is the cause of hyperplastic polyps?
decreased epithelial cell turnover and delayed shedding, with accumulation of mature cells on surface
what is the morphology of hyperplastic polyps?
well formed glands and crypts, lined by non-neoplastic mature goblet and absorptive cells
irregular tufting, sawtooth pattern secondary to delayed shedding
what are hamartomatous polyps?
malformations of mucosal epithelium and lamina propria
what is the inheritance pattern of peutz jeghers syndrome?
autosomal dominant
peutz jeghers syndrome is the result of mutation of what gene?
STK11
polyps in peutz jeghers syndrome are composed of what type of tissue?
smooth muscle
patients with peutz jeghers syndrome are at increased risk of what conditions?
intussusception, carcinoma
what physical sign is associated with peutz jeghers syndrome?
mucocutaneous pigmentation
neoplastic polyps are a precursor to what type of cancer?
colorectal carcinoma
what is the most important determinant of malignant risk for neoplastic polyps?
size
what are the four types of neoplastic polyps?
tubular adenoma
tubulovillous adenoma
villous adenoma
serrate adenoma
what is the most common neoplastic polyp?
tubular adenoma
what is the least malignant neoplastic polyp?
tubular adenoma
tubular adenomas may contain what what type of cancer?
intramucosal carcinoma
what constitutes invasive adenocarcinoma?
carcinomatous invasion of stalk of tubular adenoma
villous adenomas have a propensity for what part of the GI tract?
rectum and rectosigmoid
do villous adenomas have a stalk?
no
risk of carcinoma in tubulovillous adenoma depends on what factor?
villous proportion
which type of adenoma is most often symptomatic?
villous
which type of malignant polyp adenoma can metastasize? why?
invasive adenocarcinoma
crosses muscularis muscosae
what are the three histological conditions that must be met for adequate excision of a pedunculated adenoma?
adenocarcinoma is superficial - dose not approach margin of excision
no vascular or lymphatic invasion
carcinoma is not poorly differentiated
what is the only adequate treatment for a pedunculated or sessile adenoma?
complete resection
what does iron deficiency anemia in an older male indicate until proven otherwise?
colorectal carcinoma
what are the different types of familial adenomatous polyposis?
classic
attenuated
gardner
turcot
classic FAP is caused by mutation of what gene?
APC (adenomatous polyposis coli)
what are the clinical manifestations of gardner syndrome?
same as FAP but with distinctive extraintestinal manifestiations
benign bone tumors in skull and mandible
epidermal cysts
unerupted and/or supernumerary teeth
increased incidence of duodenal and thyroid carcinoma
what is turcot syndrome?
combination of adenomatous colonic polyposis and tumors of CNS
what is hereditary nonpolyposis colorectal cancer? what is the hallmark pathogenesis?
Lynch syndrome
inherited mutations in genes that encode proteins responsible for detection, excision, and repair of errors that occur during DNA replication
leads to colorectal tumors as well as stomach, ovary, ureters, brain, skin
what is the pathogeneis of colonic carcinogenesis?
DNA mismatch repair
poorly differentiated adenocarcinoma is indicated by the presence of what cell type?
signet ring cell
what does stage III colorectal adenocarcinoma indicate?
progression through bowel wall
carcinoid tumors secrete what hormone?
serotonin
what can be detected in the urine during carcinoid syndrome?
5-HIAA
what is the most common extra-nodal site of GI lymphomas? what is the most typical cell type?
gut
B cell
how do MALT lymphomas differ from nodal lymphomas?
MALT lymphomas are focal tumors and can be surgically resected
what is the most common tumor of the appendix?
carcinoid
mucinous cystadenomacarcinoma can lead to what condition? what is the result?
pseudomyxoma peritonei
mucus secreting cells fill abdomen
