When is this procedure indicated?
How is it performed?
Compared to conventional treatments (conformal 3D or serial IMRT), for which doses of 60-70 Gy are usually delivered in 30-35 fractions, this system, due to a helical intensity modulation of the dose (helical IMRT) allows a much more selective irradiation of the tumor and a high sparing of healthy tissues, with the possibility of delivering higher doses in a much reduced number of fractions (1-15 fractions depending on the type of treatment). This image guided radiotherapy (IGRT), allows daily monitoring of the actual position of the target volume immediately before the delivery of radiation, allowing to irradiate with greater precision organs susceptible to even minimal movements between one fraction and another (as happens, for example, in the case of the prostate gland). In addition, particular techniques of breath control (e.g. 4D Respiratory Gating), mainly used for the treatment of lung, pancreatic and hepatic neoplasms, allow to perform treatments properly synchronized with the respiratory cycle (4D Radiotherapy). By increasing the intensity of the dose administered to each individual application, it is possible to reduce the overall duration of radiotherapy treatment with the same therapeutic efficacy and fewer side effects than traditional treatment schemes. For the elaboration of the treatment plan it will be necessary to subject the patient preliminarily to a centering examination that according to the clinical indications can be: CT without mdc, CT with mdc, CT/PET, 4D CT/PET with respiratory gating, MRI with or without mdc).
The possible acute effects, generally of modest entity and duration, are related to the irradiated site and depend on the inflammation generated by the irradiation. Depending on the irradiated site, therapies to prevent these effects are prepared.
Possible late effects, generally rare, are related to the irradiated site and are managed during follow-up visits.