L7: Colon polyps and cancer Flashcards
2 Non-neoplastic polyps (benign hyperplastic)
Hyperplastic
Pseudopolyps
Who gets pseudopolyps?
IBD (they’re inflammatory)
2 classifications of Neoplastic polyps
Adenomas
Sessile serrated polyps
Facts about adenomas
2/3 of all colon polyps
Common in adults older than 50
Usually asymptomatic, large→ +/- bleed
Risk of colorectal cancer increases by number of adenomas, size, histology→ influences surveillance interval recommendations
70% of colorectal cancers arise from adenomas, takes 10 years→ Early detection & removal is key
Most common adenoma which causes 95% of colorectal cancers
Tubular adenoma
Types of adenomas
Tubular adenoma (most common)
Tubulovillous adenoma
Villous adenoma
An adenoma is considered “advanced” if…
1 cm
villous or tubulovillous
high grade dysplasia
Colorectal cancer is more common in the ______ colon
Left sided colon, but right sided rates are rising
Risk factors for colorectal cancer
Adenomas or colon cancer Familial adenomatous polyposis Hereditary nonpolyposis colon CA >50 years, but rising in younger adults 8-10 years of IBD African american Tobacco, ETOH High fat/low fiber Red meat, Obesity, DM
Colorectal cancer presenation
*Often asymptomatic* Cachetic Pallor Lymphadenopathy Abdominal distention, ascites, mass, organomegaly DRE→ hemoccult (+), rectal mass
Colorectal cancer red flags
Change in bowel habits Hematochezia or occult blood in stool *Iron Deficiency Anemia* Anorexia/Weight loss Abdominal Pain
Colorectal cancer diagnostics
CBC→ chronic blood loss→ iron deficiency anemia
Elevated Alk phos→ liver mets
Carcinoembryonic antigen (CEA) → prognostic indicator, monitor for recurrence *Not used for screening*
Colonoscopy→ biopsy to confirm
Chest/abdominal/pelvic CT→ tumor extension/complication, regional lymphatic and distal metastasis
Barium enema→ “apple core lesion”
Colorectal cancer mangement
Partial colectomy with wide margins and adjacent lymph node removal
Chemo→ metastasis
Radiation→ rectal adenocarcinoma
Colorectal cancer surveillance
Serial CEA levels
Annual surveillance CT chest/abd/pelvis
Periodic colonoscopy
What’s CEA used for again?
prognosis
monitor for recurrence
NOT for screening
Gold standard for colon cancer screening
Colonoscopy