The three speakers selected for this program are individuals that have vast experience in the topics they will address and will be able to present an overview of the developments and current status of their assignments. The topics selected have relevance to the current practice of pediatric oncology, particle radiation specially now that the use of protons is playing a very important role for the of tumors in children where it is imperative to spare as much as possible normal surrounding tissues. In adults protons are being used for the treatment of cancer of the prostate and other sites. The use of protons in adults has generated a significant debate undoubtedly due to the cost of this treatment modality. Reviewing the use of protons from a historical point of view is very appropriate given the need to support and justify an expensive treatment modality when the health care system in this country is having a very serious problem controlling the cost of it. Combined modality treatment for GI tumors has been in use for a long time. The incorporation of new chemotherapeutic agents into the treatment plans is complex and it will be very useful to review pertinent and selected data within a historical prospective. This session as planned is rather unique in that it will provide a valuable historical overview of the topics discusses and will serve as the basis for continued development and improvement of pediatric oncology, particle radiation and combined modality therapy for GI Malignancies. The format of the session for this year is similar to the one of last year which proved to be very successful. At the conclusion of this activity, the learner will be able to do the following: 1 . Describe the benefits and consequences of treating children with radiation therapy. 2. Evaluate the progress and proper role of particle radiation therapy at the present time. 3.Recognize current concepts and information regarding the use of combined modality for GI Malignancies