This book has built on the work that was presented in the previous Fascicles of the Third and Fourth Series. The authors' vast experience has led to new understanding of many aspects of pituitary pathology. With modern immunostaining and molecular techniques, classification of pituitary disease is becoming easier. Furthermore, the availability of targeted therapies has augmented the role of the pathologist in determining an accurate diagnosis. This updated volume addresses modern techniques and their application to treatment of pituitary neoplasms but retains the detailed foundation of morphology in a lushly illustrated tome, the cornerstone of the AFIP fascicles.