Light micrograph of tubular adenoma cells. A tubular adenoma is a type of pre-malignant growth (known as dysplasia) that may later develop into colon cancer if left untreated. Tubular adenomas are often removed as polyps in screening colonoscopy procedures. The cells of a tubular adenoma are columnar (elongated) and dark purple-blue in colour. The bright red dots are red blood cells in between the colon crypts that contain the tubular adenoma cells. Haematoxylin and eosin stained tissue section. Magnification: 200x when printed at 10cm.