21 - Colorectal Cancer Flashcards
__% curable if detected early
90
Without effective screening, it will remain the most common cause of cancer death in ___-_____
non-smokers
Describe the colon
- Large intestine
- From ileum to rectum
- Functions to absorb water and electrolytes
Describe the rectum
- From sigmoid colon to anus
- Functions to store stool
Describe the risk of age for colorectal cancer
-begins at age 40, and increases with age, with the mean age at presentation being 70 years
Risks for colorectal cancer
- Age
- Family history
- Alcohol intake
- Diet (high in red meats and processed meats, low in fresh fruits and vegetables)
- Smoking
- Obesity
- Inflammatory bowel disease
More than 95% of primary colorectal cancers are _________
adenocarcinomas
*this is good bc these types are sensitive to chemo and radiation
When doing surgery, what do we want to remove?
- want at least 1 cm of healthy tissue around tumor removed
- need lymph nodes to be removed so pathologist can evaluate them
- at least 14 lymph nodes
What are some signs and symptoms of colorectal cancer?
- Change in bowel habits
- Tenesmus
- Diarrhea or constipation
- Blood in the stool
- Narrow stools
- Abdominal discomfort and gas pains
- Weight loss
What is FOBT
fecal occult blood test
What sorts of treatment do we have for colorectal cancer?
1) Surgery
- The primary curative procedure for patients with stages 1, 2, and 3 disease is surgical resection of the bowel (ex. hemicolectomy or abdominoperineal section
- Resection of isolated liver and/or lung metastases
2) Radiation:
- Rectal carcinomas are associated with a local recurrence rate much higher than colon cancers. Approximately 25% of stage 2 rectal cancers and 50% of stage 3 rectal cancers may recur after surgery with no further therapy. Adjuvant radiation to the tumor bed, as well as the surgically inaccessible areas of tissue has been shown to decrease local recurrence
- Additionally, radiation can be used for palliation of symptoms
Is radiation done in colon cancer or rectal cancer ?
Only done in rectal surgery
Colon:
- surgery
- chemo
Rectum:
- surgery
- chemo
- radiation
What are metastatic sites common in colorectal cancer?
- liver
- lung
- bone
When is chemotherapy used?
In the adjuvant setting after surgical resection of Stage 2 and Stage 3 cancers.
Despite the high rate of respectability, almost half of all patients with colorectal cancer will recur because of residual disease not apparent at the time of surgery. This is the primary reason for adjuvant therapy
Describe Fluorouracil (FU)
- Most used agent in colorectal cancer
- Similar to the pyrimidine, uracil (RNA base)
- Used in both the adjuvant and metastatic setting.
- Until recently, the drug of first choice in the adjuvant setting, in combination with leucovorin
- Pattern of FU toxicity differs between bolus administration and continuous infusion
Fluorouracil (FU):
Grade 3 and 4 ______ toxicity is more common with bolus regimens
hematological
*bolus injection will also cause a lot more neutropenia and diarrhea
Fluorouracil (FU)
infusion regimens are more likely to show ______ syndrome
hand-foot
Fluorouracil (FU)
Essential component of which regimens ?
of selected irinotecan or oxaliplatin regimens
What is hand-foot syndrome?
How do you prevent and treat it?
- Painful reddening of the skin that can proceed to desquamation
- Patients should be counselled to report any changes to palms and soles ASAP when taking FU
- Prevention measures include moisturizing liberally and avoiding sources of heat and friction
- Treatment measures include topical anaesthetics, application of cold, & oral analgesics
Describe Irinotecan
- Analogue of camptothecin
- Top 1 inhibitor
- Used in the metastatic setting
- Activity in patients with FU-resistant disease as a single agent
- Currently the first line agent for Tx of metastatic colorectal cancer in combination with FU and leucovorin
- More favorable toxicity profile with regimens that contain protracted infusion regimens of FU versus bolus FU
SE of Irinotecan
diarrhea!
early onset and late onset
*can give with loperamide
Irinotecan:
used for adjuvant or metastatic
- metastatic
- results have been disappointing in the adjuvant setting
What is the 1st line Tx for colorectal cancer?
- Irinotecan
- FU
- Leucovorin
What is the max dose of Loperamide a person can take if on Irinotecan?
32 mg/day
Describe Oxaliplatin
- third generation platinum analog
- approved for both adjuvant and metastatic setting in MB
- only 15% effective as monotherapy
- up to 55% response rates when combined with FU and Leucovorin
*most regimens have FU delivered as a continuous intravenous infusion
Major side effects with Oxaliplatin
- Peripheral neuropathy
- Laryngeal spasm
- Cold intolerance