3D Conformal Radiation Therapy: Multimedia Introduction to Methods and Techniques

W Schlegel and A Mahr Berlin: Springer (2001) 107 Euros, ISBN: 3-540-14884-1. This book on CD-ROM, written by Wolfgang Schlegel and Andreas Mahr of the Radiation Physics Department of the Deutsches Krebsforschungzentrum (DKFZ) in Heidelberg, is extensive and comprehensive. It covers almost all issues of 3D conformal therapy, including the most recent developments. It is very useful as an introduction for physicists new to the field of radiation therapy and it also has its value as a reference guide for experienced medical physicists. It is particularly useful as a source of illustrations for those teaching in radiation therapy. In general the book is well written and the material is well organized. The contents of the different chapters are not very well balanced, however. Some subjects are discussed quite extensively, while others are treated very briefly. The authors explain in the introduction that the emphasis will be on the work performed at the DKFZ and that comprehensiveness was not a primary concern. Nevertheless some paragraphs could be more extensive, whereas in some paragraphs less detail would be preferable. In most cases the figures and movies illustrate the subject well and the movies in particular are often very instructive. Some of the movies, however, do not really contribute to the understanding of the subject and could be omitted. On the other hand in some paragraphs there is a lack of illustrations. The presentation on CD-ROM has great advantages as compared to a conventional book. One can navigate around easily, connections between chapters and paragraphs are easily made (via links) and one can jump directly to the reference list and back. The option of interactive illustrations and movies is a unique and nice feature. A 'find' option would be a very helpful extra to locate information. Part I on CRT with photon and electron beams starts with a chapter on immobilization with emphasis on stereotactic treatments, followed by a chapter on imaging. This could be illustrated somewhat more, e.g. by a movie or animation of MR imaging and examples of functional imaging with FDG-PET. A subject missing here is the conversion of Hounsfield numbers to relative electron densities. This is also not discussed in a later chapter. In chapter 4 on tumour localization, a movie of automated segmentation processes, e.g. obtaining a body contour or contours of lungs, could be added, and the section on different registration methods needs some illustrations. Including some mathematics on translations, rotations and 2D versus 3D registrations would be an improvement. In the following chapter on 3D treatment planning, the use of electrons is discussed very briefly, the concept of dose-volume histograms needs more explaining and paragraph 5.2 gives a rather brief account of the treatment planning process. In the chapter on dose calculations, mathematical formulae illustrating the convolution principle and the superposition method are missing. Furthermore, the latter method could be treated more extensively and the use of the Monte Carlo method for electron beam dose calculation is not discussed. The subject of plan optimization is treated in a clear way. Regarding patient positioning it would be appropriate to include some information on the registration of portal images to digitally reconstructed radiographs or to simulator radiographs. Some text about registration software and decision rules used in clinical practice should be added. Chapter 9 on treatment modalities contains a rather detailed part on linear accelerators which would be appropriate in a textbook, but here is out of balance with the treatment of subjects in most other chapters. The section on tomotherapy is very sparsely illustrated, while quite interesting material may be easily obtained. The movie on cone beam therapy, however, is an excellent example of the value of this multimedia CD-ROM. The following chapter on conformal therapy could be extended with a discussion of treatment planning aspects and requirements for dose calculation accuracy specific to CRT. The section on IMRT is of high quality, the material is well balanced and gives clear explanations. The part on verification methods is also well written. One important subject is missing, however, and this is in vivo dosimetry methods (using diodes, mosfets, EPIDs, etc). After a discussion on quality management, where the extensive reference list is of great value, chapter 12 addresses clinical radiation dosimetry. This very detailed treatment of the basics of dose measurement, including many equations, seems out of place in a book introducing conformal therapy. It would be more appropriate to summarize the various methods to verify dose distributions of CRT and IMRT treatment plans and to discuss the specific problems that have to be dealt with. These are e.g. how to determine the dose in the centre of very small and asymmetric fields, the importance of the accuracy of dose delivery outside the treatment fields and how to measure in such areas. In part II on heavy charged particles, chapter 13 starts with a very fine physics introduction, just adequate, not too much detail. Chapter 15 on dose calculations is very short. In summary, in its present form this book is worth purchasing for a radiation therapy department; it has sufficient educational value to justify the investment, but there is certainly room for improvement. We hope the group at DKFZ will undertake the task to revise the material and produce a second edition in the near future. (book review)