Term
| what characterizes the incidence of colorectal CA among race? |
|
Definition
| blacks have the highest level of colorectal CA, followed by whites, asians, hispanics, and native americans. females have slightly more colon CA, but males have slightly more rectal CA. |
|
|
Term
| are rates of colorectal CA dropping? why? |
|
Definition
| yes, due to better screening and better tx |
|
|
Term
| if you find colorectal CA early, as in it is still localized at the primary site, how does this affect 5-yr survival? |
|
Definition
| survival for the localized stage of colorectal CA is 90% as opposed to 70% for CA spread to regional lymph nodes and 12% for distant metastasis |
|
|
Term
| what is the lifetime risk for colon CA for the avg pt? |
|
Definition
|
|
Term
| how many colon CA cases occur after 50 yrs old? |
|
Definition
| 90%. most cases are among pts 60-70 yrs old. |
|
|
Term
| where geographically has the highest incidence of colon CA? lowest? |
|
Definition
| urban north america and western europe have high rates. rural south america (except argentina/uruguay), africa and south asia have low rates. |
|
|
Term
| how is it apparent that there is something about north america which increases colon CA rates as opposed to asia? |
|
Definition
| japanese men in hawaii have 2x as high of a colon CA rate than japanese men living in japan. |
|
|
Term
| how does polypectomy affect colon CA risk? |
|
Definition
| colon CA risk is 88-90% lower in pts who had a polypectomy after 6 yrs than those who didn't |
|
|
Term
| what generally characterizes colon polyps? |
|
Definition
| 67% are adenomas, 33% are hyperplastic. most are distal w/no progression. |
|
|
Term
| if a pt tries to get out of a fecal occult blood test b/c they say they just ate red meat/turnip/horseradish/vit C/have gastric irritiation what can you (the dr) say? |
|
Definition
| there is another Ig test for hemoglobin which won't be affected by these factors |
|
|
Term
| what characterizes the use of a sigmoidoscope for colon CA screening? |
|
Definition
| this looks up to the splenic flexure and can be done in-office. it is recommended every 5 yrs (based on price/efficacy) and if positive, needs to be f/u by colonoscopy |
|
|
Term
| how accurate is the fecal occult blood test? |
|
Definition
| 25-50% of FOBTs are false negatives, w/1:10 positive tests actually correlating w/colon CA. it is still the screening test of choice |
|
|
Term
| what else needs to be done along with a fecal occult blood test? |
|
Definition
| a DRE, the sensitivity of both combined is better than either alone. a FOBT and sigmoidoscopy also increases the chance of detecting colon CA. |
|
|
Term
| why do more drs do colonoscopies as opposed to sigmoidoscopies? |
|
Definition
| b/c colonoscopies can catch more colon CA than sigmoidoscopies. (65:64 neoplasms detected) |
|
|
Term
| what are the screening recommendations for a pt of avg risk >50 yrs old? |
|
Definition
| colonoscopy every 10 yrs. FOBT annually, flex sigmoidoscopy every 5 yrs. double contrast BE every 5 yrs. |
|
|
Term
| how soon do you need to screen pancolitis pts (IBD/UC) for colon CA? |
|
Definition
| 8 yrs after symptoms, then every 1-2 yrs after. 4 quadrant bx every 10 cm. |
|
|
Term
| how soon do you need to screen L-sided colitis pts (IBD/UC) for colon CA? |
|
Definition
| 15 yrs after symptoms, then every 1-2 yrs after. 4 quadrant bx every 10 cm. |
|
|
Term
| when do FAP/HNPCC pts need to be screened? at what rate should they get a colonoscopy? |
|
Definition
| 10 yrs pre herald case or at 40 yrs. a colonoscopy should be performed every 1-5 yrs on these pts |
|
|
Term
| what is a virtual colonoscopy? |
|
Definition
| a computer enhanced CT spiral CT after bowel prep and air insufflation, which is fairly sensitive and visualizes the entire colon. it is not the standard of care. |
|
|
Term
| how do rectal and colon CA compare in terms of incidence? |
|
Definition
| rectal CA is still more common, but colon CA is gaining in the US. both have different risk factors and tx. |
|
|
Term
| why is frequency of R sided colon CA increasing? |
|
Definition
| b/c more colonoscopies are being performed now rather than sigmoidoscopies |
|
|
Term
| what contributes to colon CA risk diet-wise? |
|
Definition
| low fiber diet (fiber increases transit time of toxins and binds them). increased saturated fats and decreased cruciferous vegetables (cabbage) |
|
|
Term
| what are important family hx questions to ask pts when evaluating colon CA risk? |
|
Definition
| how many 1st degree relatives (doubles risk), age of dx and number of incidences. several relatives with a colon CA hx at <50 yrs increases risk 6x. |
|
|
Term
| what aspects of a pts personal hx increase colon CA risk? |
|
Definition
| any kind of CA hx. hx of adenomatous polyps, IBD (UC > CD), *women w/a cholecystectomy 15 yrs later, diverticulitis, schistosoma japonicum hx, and hx of radiation therapy |
|
|
Term
| what are potentially good chemoprevention nutrients which may decrease colon CA risk? |
|
Definition
| vit E, NSAIDs, and cox-2 inhibitors (decrease polyp #) |
|
|
Term
|
Definition
| T1 = submucosa, T2 = muscularis propria, T3 = serosa/peri-colic/rectal tissue, T4 = perforation of visceral peritoneum/other organs+structures |
|
|
Term
| what is late stage colon CA? |
|
Definition
|
|
Term
| how are colon and rectal CA differentiated? |
|
Definition
| colon CA is >15 cm from the anal verge, rectal CA is anything closer or below the peritoneal reflection |
|
|
Term
| what are the morphologic features of colon CA? |
|
Definition
| villus ademonas are characterized by: mucin production, rectal discharge, diarrhea w/mucus, soft/velvety feel, flat and spreading |
|
|
Term
| what are surgical emergencies associated with colon CA? |
|
Definition
|
|
Term
| what are the general clinical features of colon CA? |
|
Definition
| wt loss (10%), hematochezia, melena, jaundice (liver mets), pain (dull ache unless obstruction), and anemia |
|
|
Term
| what are the specific clinical features of L-sided colon CA? |
|
Definition
| constipation alternating w/diarrhea. obstruction and pain. |
|
|
Term
| what are the specific clinical features of R-sided colon CA? |
|
Definition
| vague abdominal ache, bleeding, anemia, wt loss, and weakness |
|
|
Term
| what are the clinical features of rectal CA? |
|
Definition
| tenesmus (painful spasms of the anus w/constant feeling of need to empty the bowel), inadequate emptying, urgency, bleeding, and a change in bowel habits/character (pencil thin). *this makes sense b/c your body thinks there is still something in there* |
|
|
Term
| what do you do when you know a pt has colon CA? |
|
Definition
| you do a CEA (carcinoembryonic antigen), which is a maintenance/follow up test (*however this is NOT diagnostic*). after sx, you repeat the CEA. PET scan (checks metabolism of different tissues and tumors are more active). bx (no meat/no treat). CT scan (need this to read PET scan). |
|
|
Term
| what is recommended therapy for colon CA? |
|
Definition
| attempt complete resection, then chemo (mainly for colon) esp for stage III/IV. |
|
|
Term
| what is bevacizumab? has this been shown to help much w/adjuvant colon CA tx? |
|
Definition
| a monoclonal antibody against VEG-F, it has not been shown to be effective in adjuvant colon CA tx. |
|
|
Term
| what are chemotherapeutic options for metastatic colon CA? |
|
Definition
| bevacizumab, cetuximab (EDGF receptor antagonist), irinotecan (highly effective), and oxaliplatin (platinum drug - highest response rate) |
|
|
Term
| what is the best tx to start with in rectal CA? |
|
Definition
| combination chemo/radiotherapy (radio - not as good for colon, b/c of movement). 5-florouracil is commonly used. sx is only used first for obstruction. |
|
|
Term
| what is the prognosis for anal CA? what is tx? |
|
Definition
| good. tx is usually sx, then radiation w/ or w/o chemotherapy. |
|
|
Term
| what is the main reason pancreatic CA has a poor prognosis? |
|
Definition
| it is generally asymptomatic (no pain) until it is too late to tx |
|
|
Term
| what are risk factors for pancreatic CA? |
|
Definition
| tobacco, ETOH, pancreatitis, DM, and pernicious anemia |
|
|
Term
| what is tx for pancreatic CA? |
|
Definition
| sx, then adjuvant chemo/radiotherapy. if metastatic, palliative care. chemo: gemcitabine, fluorouracil, and platinums |
|
|
Term
| what characterizes incidence of liver CA? |
|
Definition
| not a big problem in the US, but a huge problem worldwide. |
|
|
Term
| what are risk factors for liver CA? |
|
Definition
| hepatitis B/C, cirrhosis, aflatoxins |
|
|
Term
| how do pts with liver CA present? |
|
Definition
| RUQ abdominal pain, wt loss, liver mass |
|
|
Term
| what diagnostics need to be run for liver CA? |
|
Definition
| liver panel, *AFP, hepatitis panel |
|
|
Term
|
Definition
| sx (cryo, RF ablation), chemoembolization, liver transplant, and systemic chemo + hep artery infusion. |
|
|
Term
| what kinds of CA affect esophageal CA? |
|
Definition
| 50-50 split between squamous and adenocarcinoma. |
|
|
Term
| what are risk factors for esophageal CA? |
|
Definition
| GERD w/barret's esophagus, ETOH, tobacco |
|
|
Term
| how is esophageal CA usually diagnosed? |
|
Definition
| esophageal CA is usually asymptomatic until 50-75% stenotic (dysphagia w/solids, not liquids) |
|
|
Term
| what is the prognosis for esophageal CA? |
|
Definition
|
|
Term
| how is esophageal CA treated? |
|
Definition
| early: sx. advanced: chemo/radio, neo-adjuvant. metastatic: palliation |
|
|
