Wayne State University Libraries have many books relevant to the study of Cytopathology and Pathology.
Much of the Pathology/Cytopathology book collection is located at Shiffman Medical Library but may also be held at other WSU libraries or can be requested from other Michigan libraries (order through MeLCat) or other libraries (order through ILLiad).
In general, Pathology books have Library of Congress call numbers starting with RB. However, depending on the specific body system the call number may vary.
You can find books by searching the University Libraries online catalog: http://elibrary.wayne.edu/search/X