Note: The required total count of mitoses is per 5 mm2 on the glass slide section. With the use of older model microscopes, 50 HPF is equivalent to 5 mm2. Most modern microscopes with wider 40X lenses/fields require approximately 20 to 25 HPF to encompass 5 mm2. If necessary, please measure field of view to accurately determine actual number of fields required to be counted on individual microscopes to encompass 5 mm2.