Key features of the three variants of hyperplastic polyp
| Variant | Clinical | Histological features |
|---|---|---|
| Microvesicular | Mainly found in the distal colon and rectum Usually less than 5 mm diameter | Well-organised arrangement of crypts Serration and goblet cells limited to superficial half of crypts Microvesicular mucin droplets in epithelial cells* Thickened basement membrane Vertically orientated smooth muscle fibres |
| Goblet cell | Distal colon and rectum Almost always less than 5 mm diameter | May resemble normal mucosa on initial examination Mucosal thickening Prominent mature goblet cells Surface tufting |
| Mucin poor | Rare | Similar to microvesicular type but both goblet cells and microvesicular mucin are less evident |
*This imparts a glassy or hazy quality to the cytoplasm.