SLIDE 1

Sample 1	Sample 2
Sample 3	Sample 4

Slide 1 has examples of signature lesions of PyV-mT,(Muller) myc (Seldin) and erbB2 (Leder). The four samples allow the student to compare and contrast the different signature lesions. The two examples of myc-type tumors (Samples 2 and 3) permit observation of different myc tissue patterns while retaining the basic myc type cytology. Tumor Sample 1 invades the surrounging tissue and blood vessels. Sample 2 has areas of dense fibrosis and a solid, cord-like pattern. Sample 3 is cystic and secretory. Although the tumor is expansile with a well defined capsule, one area has invasion of the capsule. In addition, sample 3 has an excellent example of grade 1 MIN. Sample 4 has two excellent examples of the solid, nodular intermediate cell configuration of erbB2 and a marked histiocytic host response with dPAS positive macrophages.