• Barbara Alicja Jereczek-Fossa, Federica Cattani, Cristina Garibaldi, Dario Zerini, Raffaella Cambria, Genoveva Ionela Boboc, Marco Valenti, Anna Kowalczyk, Andrea Vavassori, Giovanni Battista Ivaldi, Mario Ciocca, Deliu Victor Matei, Ottavio De Cobelli, and Roberto Orecchia.
• Department of Radiation Oncology of the European Institute of Oncology, Milan, Italy. barbara.jereczek@ieo.it
• Strahlenther Onkol. 2007 Nov 1; 183 (11): 610-6.

PurposeTo evaluate the feasibility and accuracy of daily B-mode acquisition and targeting ultrasound-based prostate localization (BAT) and to compare it with computed tomography (CT) and electronic portal imaging (EPI) in 3-dimensional conformal radiotherapy (3-D CRT) for prostate cancer.Patients And MethodsTen patients were treated with 3-D CRT (72 Gy/30 fractions, 2.4 Gy/fraction, equivalent to 80 Gy/40 fractions, for alpha/beta ratio of 1.5 Gy) and daily BAT-based prostate localization. For the first 5 fractions, CT and EPI were also performed in order to compare organ-motion and set-up error, respectively.Results287 BAT-, 50 CT- and 46 EPI-alignments were performed. The average BAT-determined misalignments in latero-lateral, antero-posterior and cranio-caudal directions were -0.9 mm+/-3.3 mm, 1.0 mm+/-4.0 mm and -0.9 mm+/-3.8 mm, respectively. The differences between BAT- and CT-determined organ-motion in latero-lateral, antero-posterior and cranio-caudal directions were 2.7 mm+/-1.9 mm, 3.9+/-2.8 mm and 3.4 +/- 3.0 mm, respectively. Weak correlation was found between BAT- and CT-determined misalignments in antero-posterior direction, while no correlation was observed in latero-lateral and cranio-caudal directions. The correlation was more significant when only data of good image-quality patients were analyzed (8 patients).ConclusionBAT ensures the relative positions of target are the same during treatment and in treatment plan, however, the reliability of alignment is patient-dependent. The average BAT-determined misalignments were small, confirming the prevalence of random errors in 3-D CRT. Further study is warranted in order to establish the clinical value of BAT.

27 keywords...

hide…