While our knowledge about cancer is proliferating rapidly, our principles of cancer medicine for individual patients and for populations are evolving only gradually. Our fundamental understanding of cancer causes and deve lopment is incomplete, and our treatments are nonspecific and less often curative than we would like. Nevertheless, worldwide, our major challenge remains to apply to our populations all that we know about cancer. To meet this challenge, doctors everywhere need a broad view and under standing of cancer causes and control. This book is intended for doctors-in-training and clinical medical practi tioners; it provides principles across the breadth of cancer medicine. The editors and authors believe that it is possible to reduce the exposition of current knowledge to the compact 40 chapters and 600 pages presented here without losing the comprehensiveness, richness, and pragmatic detail that doctors need. This compilation presumes knowledge of the basic sciences, particularly genetics, pathology, anatomy, and physiology. We have tried to balance scientific exposition with practical material in preven tion, early detection, and palliative care, which are the major areas of pub lic health medicine where greater attention is needed worldwide. While this book is based, in part, on material prepared for previous edi tions, each chapter has been newly written and edited by the authors and editorial staff for this edition."

The continuing success of the VICC's Manual of Clinical Oncology and the continuing refinement of our educational objectives in cancer designed for graduating medical students and young practitioners, cou pled with significant additional knowledge in the cancer field have allIed to the decision to publish a Fourth Edition. The collaboration of the World Health Organization (WHO) and the Pan-American Health Orga nization (PAHO) in our international and regional conferences in cancer education and the development of courses using the Manual as a basic resource have aided further definition of the VICC's role in cancer educa tion throughout the world. Our Revision Committee believes that we have incorporated in this small volume most of the knowledge about cancer which is essential for all students and practioners to know and that we have done so in a clear and concise manner. A large proportion of the material presented herein is devoted to basic aspects, yet presented so that the clinical implications are clear. Although we do not feel that general physicians need to know minor details about all cancers, we feel it is particularly important to be somewhat thorough in our discussions of the more common cancers. We have omitted discussion of the rare cancers, and limited ourselves to the major concepts and princi ples of the less common cancers.

Chromosome abnormalities of cancer cells have been recognized for a long time, and have generally proven to be a highly specific marker ofmalignancy. The contri- butions collected in this book, "Tumor Aneuploidy", cover several major aspects of present knowledge conceming the occurrence and clinical significance of chromo- some abnormalities as delineated by karyotype analyses or measurements of the cellular DNA content. Certain non-random clonal chromosome losses, deletions and translocations ap- pear to represent primary genetic lesions of malignancies and reflect their clonal origin. Secondary intraneoplastic genetic evolution is suggested by major clonal ab- normalities of chromosome number and cellular DNA content. Both types of ge- netic changes have been reaching great relevance in cancer medicine, today. Although the Philadelphia chromosome was first discovered in chronic myelo- cytic leukemia (CML), by Nowell and Hungerford in 1960, new banding techniques developed in the 1970's were needed to identity this abnormality as a translocation between chromosomes 9 and 22 (t(9; 22)). Soon thereafter, further non-random translocations were detected and attributed to special diseases like t(8; 21) and t(15; 17) to acute myeloid leukemias (AML) and t(9; 22), t(4; 11), t(8; 14) to acute lymphoblastic leukemia (ALL).