Mucinous Borderline Tumor
Cytologic atypia in a mucinous borderline tumor (MBT) - intestinal type: The left half of the gland is lined by a single layer of columnar mucinous cells with basally located nuclei lacking atypia. The right half shows a more complex architecture with papillary and cribriform areas. There is greater degree of cytologic atypia consisting of nuclear enlargement and hyperchromasia with punctate or occasionally prominent nucleoli. The appearance resembles adenomatous colonic polyp. High-grade nuclear features are not seen. A few scattered mitotic figures are present. There is no destructive stromal invasion.