Colorectal Carcinoma Flashcards
What type of cancer are colorectal carcinomas
Adenocarcinoma
Risk Factors
Sporadic (usually)
PMH - IBD, Adenoma, CRC
FH - Genetics: FAP, HNPCC
SH - Age, Male, Alcohol, Smoking, Obesity, Lack of exercise, Diet (low-fibre, lots red and processed meat)
How are CRC related to colorectal polyps
Most CRC’s arise from polyps (protuberant growths)
Describe the adenoma carcinoma sequence
- Activation of oncogene
- Loss of tumour suppressor gene
- Defective DNA repair pathway
Left sided presentation of CRC
PR bleeding / mucous
Altered Bowel habit or obstruction
Tenesmus
Mass
Right sided presentation of CRC
Weight loss
Decreased Hb
Abdominal Pain
Presentation of either side
Abdominal pain
Perforation
Haemorrhage
Fistula
Main Investigation
Colonoscopy - with biopsy
Other Investigations
FBC (anaemia)
FOB
DNA test (if FH)
Staging Investigations
CT chest / abdo / pelvis
MRI for rectal tumours
PET Scan
Rectal Endoscopic Ultrasound
Dukes Staging
A - limited to muscularis mucosae
B - extension through muscularis mucosae
C - involvement of regional lymph nodes
D - distant metastases
TNM Staging - T
Tx - primary tumour cannot be assessed
T0 - no evidence of primary tumour
Tis - carcinoma in situ
T1-4 - size and / or extent of primary tumour
- 1 = small tumour with minimal invasion
- 4 = large tumour with extensive invasion
TMN Staging - N
Nx - nodes cannot be assessed
N0 - no node involvement
N1-3 - regional node metastases
TNM Staging - M
M0 - no distant spread
M1 - distant metastases
Surgery Options
Right hemicoloectomy - caecal, ascending, proximal transverse colon tumours
Left hemicolectomy - distal transverse, descending colon
Sigmoid colectomy - sigmoid tumours
Resection - rectal tumours
Laparoscopic surgery best
Liver resection - single lobe hepatic mets
