An example of upper urinary system in situ urothelial carcinoma (CIS).1. Classification of the lesion as a high-grade in situ lesion...

It's uncommon, but once in a while, blue nevi are encountered in colonic mucosa and present as dark patches. Case provided by Dr....

This epithelioid malignant peripheral nerve sheath tumor shows loss of INI1/SMARCB1, a feature of this type of neoplasm....