19 / 40
Right colon (28%)
Midgut embryonic origins
1
Histology – Physiology
1
:
•
Nutrient and water absorption
•
Carbohydrate fermentation
®
short chain fatty acids
Microbiota – Immunology
1,2,3
:
•
Immune activity
•
Short chain fatty acids
•
Neutral mucin expression
Symptomology
2,3,4
:
•
Subtle symptoms (e.g. anaemia)
•
Common features vs left include:
•
High TNM stage
•
Large tumours
•
Vascular invasion
•
Mucinous type
•
High grade
•
Invasive tumour border
•
More common in women than men
Molecular
5,6,7
:
•
High MSI, CIMP, BRAF MT frequency
•
CMS1
•
KRAS MT, expression EGFR
•
Serrated pathway
Left colorectum (72%)
Hindgut embryonic origin
1
Histology – Physiology
1
:
•
Nutrient and water absorption
•
Protein fermentation
•
Faecal storage
•
Goblet cells
•
Endocrine cells
Microbiota – Immunology
1,2,3
:
•
Immune tolerance
•
Mucosal bacterial counts
•
Mutagenic/ carcinogenic metabolites
•
Neutral mucopolysaccharide predominance
•
Acid mucin predominance
Symptomology
3
:
•Symptoms often more evident
•Typically earlier stage at diagnosis
Molecular
6,7
:
•
High CIN frequency. KRAS MT, HER2
•
CMS2
•
EREG, TS, VEGFR2, ERCC1 expression
FACTOR PRONÓSTICO