How does a pathologist make a diagnosis at the microscope?
After the specimen is processed and microscopic slides are prepared, the pathologist proceeds to examine it. Important clues to the diagnosis may have already been gleaned from careful examination of the gross specimen. For example, a melanoma of the skin often presents as a large black tumor when sections are taken through it. But the final diagnosis always rests upon what is seen under the microscope. A pathologist places the stained glass slide under the microscope and then proceeds to view it under a scanning low power magnification. This is usually at a magnification of 20-40x. This initial screening process answers several questions.