AGA Technical Review on the Diagnosis and Management of Colorectal Neoplasia in Inflammatory Bowel Disease

(A) High-power photomicrograph of a biopsy specimen from a patient with UC showing serrated LGD. The contour of the luminal epithelium shows infolding and slight serration, but the nuclei are predominantly basally located with little evidence of stratification and only a mild degree of nuclear atypia. (B) High-power photomicrograph of the surface mucosa from a patient with UC and an underlying moderately differentiated adenocarcinoma (not shown). The surface mucosa shows hypermucinous villiform epithelium without significant cytologic atypia of the cell nuclei.

(A) High-power photomicrograph of LGD in UC. The mucosa is slightly villiform in contour and contains dysplastic columnar cells with enlarged pencil-shaped nuclei, slight nuclear stratification, increased mitoses, dystrophic goblet cells, and slight loss of nuclear polarity. (B) In contrast to panel A, this biopsy specimen shows an increased degree of architectural and cytologic atypia consistent with HGD. The glands show a back-to-back configuration and are lined by highly dysplastic cells with full-thickness nuclear stratification, marked loss of nuclear polarity, increased numbers of mitoses, some atypical, and dystrophic goblet cells. (C) In this biopsy specimen from a patient with UC, the degree of architectural and cytologic atypia is consistent with intramucosal adenocarcinoma. There is a complex arrangement of back-to-back glands, with cribriforming of the luminal epithelium, and an infiltrative appearance of the glands in the lamina propria. The cells show a high N/C ratio and marked loss of polarity.

(A and B) Endoscopic images of adenoma-like DALMs. Images provided courtesy of Jerome D. Waye, MD.

(A and B) Endoscopic images of non–adenoma-like DALMs. Image 4B provided courtesy of Jerome D. Waye, MD.

(A) Medium-power view of an adenoma-like DALM occurring in a patient with UC. This lesion was located within an area of established chronic colitis. However, it was smooth and well-circumscribed grossly. Microscopically it shows the typical features of a sporadic tubular adenoma. There was no evidence of flat dysplasia elsewhere in the colon from this patient. This patient was treated with polypectomy and continued surveillance and has been negative for dysplasia after 8 years of follow-up. (B) High-power photomicrograph of a well-circumscribed adenoma-like polyp within an area of chronic UC. This lesion shows a mixture of low-grade dysplastic glands and nondysplastic glands at the surface of the polyp. There is also an increased degree of inflammation in the lamina propria. This lesion was interpreted as an adenoma-like polypoid area of dysplasia in UC because of the histologic features of the lesions and the association with flat LGD in areas surrounding the polypoid lesion. (C) Low-power view of a tissue section from a non–adenoma-like DALM in UC. The section shows elongated finger-like “papillary” projections of predominantly low-grade, dysplastic columnar epithelium. This lesion represented the surface of a non–adenoma-like DALM, which was sessile, broad based, and showed an irregular surface contour. After pathologic evaluation of the resection specimen, a well-differentiated adenocarcinoma with infiltration into the submucosa was evident.

Proposed management scheme for DALMs in IBD.⁷⁹

Recommendations for the management of flat and raised dysplasia. Modified and reprinted with permission from Elsevier.⁶⁸