August 13, 2015 - Colorectal Neoplasia Flashcards
The Beginning of Colorectal Cancer
This begins with polyps along the colon.
The polyps can either be adenomatous (neoplastic or premalignant), or non-adenomatous (not neoplastic and not premalignant). Either way, the polyps are removed and biopsied.
Adenomatous Polyps
Resemble glandular structures (form from glands). These are neoplastic or premalignant.
Only 5-10% of polyps are under this category, however these will turn into cancer over a period of 5-10 years.
Adenomas and Carcinomas
Adenomas will turn into carcinomas over a period of 5-10 years.
Polypectomy
The removal of polyps.
Polyps are snared with a metal wire and an electric current is passed through the wire which burns the skin and cauterizes the wound. The polyps are then removed.
Family History and Colorectal Cancer
1st degree relative with CRC before age 65 increases your relative risk by approximately 2.0.
Two or more 1st degree relatives increases your relative risk 3-4 times.
Having a 1st degree relative who got CRC before age 45 increases your risk 5 times.
Modes of Spread of CRC
- Direct continuity
- Transperitoneal spread
3. Lymphatic spread to regional lymph nodes
4. Hematogenous spread (especially to the liver)
Bold is most common methods for CRC
Colorectal Cancer Prognosis
Stage 1 - 95%
Stage 2 - 60-80%
Stage 3 - 20-50%
Stage 4 - 5%
CRC has a fairly good prognosis when detected early.