Room: AAPM ePoster Library
Adrenal glands are common location for methasthases from different primary disease sites. Traditinal treatments for adrenal methastasis have been usually carried out by means of some of the following alternatives: adrenalectomy, chemotherapy or radiofrequency. Delivery of high doses by means of stereotactic body (SBRT) techniques have made possible to treat these disease locations in a efective way. The present study shows the location and dosimetric results in the treatment of adrenal locations combining volumetric treatments (VMAT) and breathing-related motion control by means of a dampening system.
exaCradle is a multi-dampening system than can combine eight different compression points. This device allows to adapt the immobilization for each patient and site in SBRT treatments. Data for four patiens with adrenal lesions have been gathered, with three compression points: anterior, anterior-oblique and lateral. 4 CT datasets were acquired for each patient (free breathing, maximum inspiration and expiration breathold and ultra-slow CT acquisition by means of cone beam CT imaging in the treatment unit). All image sets were registered in order to generate the ITV by combining the CTVs contoured for each dataset. PTV was defined as a 5 mm expansion from ITV. Treatments were planned with Monaco 5.1 (Elekta) and delivered with a Synergy (Elekta) linac by means of VMAT techniques. For each fraction, 3 or 4 CBCT scans were performed: pre-treatment (inter-fraction correction, repeated when corrections exceed ITV-PTV margin), mid-treatment (intra-fraction correction) and post-treatment (final evaluation).
Dose-volume parameters (D95, V107 for PTVs; Dmax, Dmed for OARs) were reported. In all cases, the goals of the treatment were achieved. Location parameters were under ITV-PTV margin, excepting 3 pre-treatment scans.
Immobilization provided by the studied device, together with VMAT and IGRT techniques allowed to deliver treatments for adrenal locations in a safe and effective way.