Colorectal Cancer Talk
Risk Factors
- Hereditary:
o HNPCC (Lynch): mismstach repair genes, R sided lesions, lymphocytic histolog-assoc with endometrial cancer (50-60% of women), renal cell, gastric
 Amsterdam Criteria: 3-2-1
 Bethesda Guidelines
o FAP: APC gene mutation, young age, colectomy
- IBD: Ulcerative colitis definitely (inc with PSC), probably in crohn's
o Screening recommendations – 8 years after diagnosis, then yearly
- Prior Adenomas
- ?able fiber in diet (no conclusive data)
- ?able assoc between adenomas and central obesity
- ?able AA males have inc risk - the american gastroenterology assoc recommend
screening start at age 45 but this is not recommended by USPSTF
Screening
Recommended by USPSTF for patients aged 50-75
Options:
1. Colonoscopy Q10 years
2. Flex Sig Q 5 years with FOBT yearly
3. FOBT: yearly
5. Double Contrast Barium Enema Q 5 years
6. CT Colonography Q 5 years
You have your c-scope and they find:
Adenoma: if high grade or very large may need repeat c-scope more quickly (i.e. 5-6 months)
otherwise time to repeat varies by size and practitioner but likely closer to every 3-5 years
Staging/Monitoring:
Colon Cancer
- IMAGING:
o CT A/P vs. MRI for liver lesions
o controversy re: chest imaging given high prevalence of incidentalomas
- LABS:
o CEA, CA19-9 more for help with post-surgical monitoring
Rectal Cancer
- IMAGING: TransRectal US to evaluate depth of invasion, CT C/A/P (since rectal ca more
likely to bypass liver given drainage into IMV)
- LABS: CEA
Surgical Options for Rectal Cancer
1. Upper 2/3  Primary Resection with Coloanal Anastomosis
2. Lower 1/3 or within 5-6 cm of dentate line  APR
Neoadjuvant Therapy (i.e. therapy prior to surgery)
- Medications Used: 5FU + Leucovorin
- Indications:
o if close enough to dentate line that able to do coloanal anastomosis with
sphincter sparing after chemoXRT
o T3/T4 disease
o + nodes on TRUS
Management by Stage
- Stage 2: post-op 5FU + Leucovorin, unclear whether oxaliplatin has any affect on
-
disease free survival (DFS)
Stage 3: FOLFOX
Stage 4/Mets:
o Potentially Resectable: down-stage with systemic chemo +/- chemoembolization
of hepatic lesions
o Not Potentially Resectable
 1st Line: FOLFOX vs. XELOX (5FU, leucovorin, oxaliplatin) (xelox with
xeloda/capecitabine
 2nd Line: repeat of either of the above or FOLFIRI