000			03274cam a2200205 4500
001			NMDX7776
008			120401t2018 xxu||||| |||| 00| 0 eng d
100			_aSarwar, A.
240			_aClinical Oncology
245			_aProstate movement and deformation in fractionated prostate radiotherapy
260			_c2018
500			_aNMUH Staff Publications
500			_aEMBASE
500			_a30
520			_a<span style="font-size: 10pt;">Aims: Despite image-guided radiotherapy for prostate cancer, there remain uncertainties regarding dose delivered to intended planning target volumes [1]. To reduce intra-fraction variability, daily bowel and bladder preparation are now incorporated in most protocols [2]. However, the impact of these on prostate movements (PM) and deformation (PD) is yet not completely understood to aid anisotropic margins [3]. Our aim is to assess the impact of differential rectal filling on PM and PD. Methods: Our hypothesis is that prostate deformation is independent of prostate movement and should be incorporated in daily set-up correction. This study will assess the correlation of rectal volume to prostate volume, movement and deformation in 10 consecutive patients treated with 60 Gy/20 fractions. Here we present the data on prostate movement on the initial 4 patients. We intend to measure prostate deformation using distance in each orthogonal direction from the centre of mass of the prostate to prostate margins to acquire deformation vector fields for deformation volume histograms. We will then compare PM and PD. Results: The mean rectal volume was 42.94 ml +/- 11.98 ml. The mean prostate volume (PV) was 37.64 ml +/- 18.63 ml. The mean translational errors were: vertically e3.2 +/- 0.41 mm, longitudinally e0.4 +/- 0.24 mm and laterally 0.3 +/- 0.25 mm. Rectal volume correlated with the PV r</span><sup><span style="font-size: 10pt;">2</span></sup><span style="font-size: 10pt;">= 0.80 (P < 0.001, 95% CI 0.611 to 0.761). Majority of the movement in the 3 co-ordinates was superiorly (75%), anteriorly (44%) and to the right (50%).There appears to be limited correlation of prostate volume with translational movements, vertically: r</span><sup><span style="font-size: 10pt;">2</span></sup><span style="font-size: 10pt;"> = 0.27 (P < 0.01, 95% CI e0.009 to e0.004), longitudinally (r</span><sup><span style="font-size: 10pt;">2</span></sup><span style="font-size: 10pt;"> = 0.03, P = 0.89, 95% CI e0.002 to 0.000) and laterally r</span><sup><span style="font-size: 10pt;">2</span></sup><span style="font-size: 10pt;"> = 0.00 (P = 0.83, 95% CI e0.001 to 0.001). Conclusion: Our preliminary results demonstrate that prostate volume is influenced by rectal volume. However, the correlation between PM and PV is limited. We are currently analysing the relationship between PD, PM and PV to budget for prostate deformation for fractionated radiotherapy. [Conference abstract]</span>
700			_aSinghera, M.
700			_aPapastavrou, Y.
700			_aJani, Z.
856			_uhttp://www.clinicaloncologyonline.net/article/S0936-6555(17)30529-0/fulltext
999			_c76567 _d76567