Since the publication of the Third Series Fascicle on Tumors of the Kidney, Bladder, and Related Urinary Structures in 1994, there has been a revolution in our understanding of the clinical, pathologic, and molecular features of these lesions. Thus, it is fitting that this volume should be the first of the Fourth Series Tumor Fascicles.

In the Fourth Series in general, and in this fascicle in particular, there is an increased emphasis on new molecular findings which are relevant to diagnostic tumor pathology, as well as on the diagnostic features of aspiration and exfoliative cytopathology. Differential diagnosis is also emphasized, and numerous tables summarize important differential diagnostic considerations, including the appropriate roles of immunohistochemical stains. Important recommendations for gross dissection and surgical pathology report construction are also included.

Drs. Murphy, Perlman, and Grignon have expanded the Third Series Fascicle by approximately twenty percent, and almost all of the 586 illustrations are now in color. The 1530 references in five chapters are comprehensive and up to date.