ABSTRACT
The use of imaging to maximize precision and accuracy throughout the entire process of radiation therapy (RT) delivery has been called "Image-guided RT" (IGRT). RT has long been image guided: in fact, historically, the portal films and later electronic megavoltage images represented an early form of IGRT. A broad range of IGRT modalities is now available and adopted. The target location may be defined for each treatment fraction by several methods by localizing surrogates, including implanted fiducial markers, external surface markers or anatomical features (through planar imaging, fluoroscopy, KV or MV computed tomography, magnetic resonance imaging, ultrasound and X-ray imaging, electromagnetic localization, optical surface imaging, etc.). The aim of the present review is to define practical recommendations for IGRT.
Subject(s)
Neoplasms/radiotherapy , Radiotherapy, Image-Guided , Fiducial Markers , Humans , Italy , Radiometry , Radiotherapy Dosage , Radiotherapy Planning, Computer-AssistedABSTRACT
Despite the risk of long-term side effects, external radiation therapy remains a cornerstone of the treatment for many cancers in childhood, in particular for brain tumours and head and neck cancers. Conformal radiation has been the standard of care since several decades. However, new techniques, including stereotactic radiation, intensity-modulated radiation therapy, or protontherapy have proven many advantages in adults, and are more and more discussed in pediatric management due to a favourable cost/benefit rate in some situations. The aim of this article is to point out the potential indications as well as the limits of these new techniques in childhood.
Subject(s)
Neoplasms/radiotherapy , Neoplasms/surgery , Radiosurgery/methods , Radiotherapy, Intensity-Modulated/methods , Bone Neoplasms/radiotherapy , Bone Neoplasms/surgery , Brain Neoplasms/radiotherapy , Brain Neoplasms/surgery , Child , Head and Neck Neoplasms/radiotherapy , Head and Neck Neoplasms/surgery , Humans , Neoplasms, Radiation-Induced/etiology , Radiosurgery/adverse effects , Radiotherapy, Intensity-Modulated/adverse effects , Ribs , Spinal Neoplasms/radiotherapy , Spinal Neoplasms/surgeryABSTRACT
In this study the authors retrospectively evaluated the feasibility and effectiveness of prolonged oral etoposide therapy in children with recurrent ependymoma. Twelve ependymoma patients with documented recurrent or persistent disease were treated between May 1998 and October 2003. All patients were treated monthly with oral VP-16 administered at a dose of 50 mg/m2/d for 21 days, with a 7-day interval between cycles, for a planned minimum number of six cycles. Response (complete plus partial) after two cycles occurred in 5 of the 12 patients (41.6%). Response plus stable disease occurred in 10 of the 12 (83.3%), with a median duration of response or stable disease of 7 months (range 4-30). The median survival was 7 months; the 2-year progression-free survival was 16.7%. These results emphasize that oral etoposide is an attractive option for childhood recurrent ependymomas in terms of administration, tolerability, and neuroradiologic response.
