Intrafraction Motion of the Prostate During External-Beam Radiation Therapy: Analysis of 427 Patients with Implanted Fiducial Markers

Kotte, A.N.T.J.; Hofman, P.; Lagendijk, J J W; Vulpen, Marco van; Heide, Uulke A. van der

doi:10.1016/j.ijrobp.2007.03.029

Cited by 185 publications

(155 citation statements)

References 26 publications

Supporting

Mentioning

140

Contrasting

Order By: Relevance

“…CTV2 represented the prostate and proximal seminal vesicles within the first

0.5 - 1.0 cm

. These CTVs were compatible with the RTOG0415 protocol on IMRT for prostate cancer, and the results of internal motion studies after online correction using implanted markers by Meijer et al, van der Wielen et al, and Kotte et al ( 19 – 21 ) In this study, the PTVs were created by expanding the respective CTVs by 0.8 cm around the seminal vesicles and 0.5 cm around the prostate.…”

Section: Methodssupporting

confidence: 78%

The effects of motion on the dose distribution of proton radiotherapy for prostate cancer

Qamhiyeh

Geismar

Pöttgen

et al. 2012

J Applied Clin Med Phys

View full text Add to dashboard Cite

Proton radiotherapy of the prostate basal or whole seminal vesicles using scattering delivery systems is an effective treatment of prostate cancer that has been evaluated in prospective trials. Meanwhile, the use of pencil beam scanning (PBS) can further reduce the dose in the beam entrance channels and reduce the dose to the normal tissues. However, PBS dose distributions can be affected by intra‐ and interfractional motion. In this treatment planning study, the effects of intra‐ and interfractional organ motion on PBS dose distributions are investigated using repeated CT scans at close and distant time intervals. The minimum dose (normalDmin) and the dose to 2% and 98% of the volumes (normalD2% and normalD98%), as well as EUD in the clinical target volumes (CTV), is used as measure of robustness. In all patients, normalD98% was larger than 96% and normalD2% was less than 106% of the prescribed dose. The combined information from normalDmin, normalD98% and EUD led to the conclusion that there are no relevant cold spots observed in any of the verification plans. Moreover, it was found that results of single field optimization are more robust than results from multiple field optimizations.PACS numbers: 87.55.D‐, 87.55.de, 87.53.Bn, 87.55.dk, 87.55.ne

show abstract

“…CTV2 represented the prostate and proximal seminal vesicles within the first

0.5 - 1.0 cm

Section: Methodssupporting

confidence: 78%

The effects of motion on the dose distribution of proton radiotherapy for prostate cancer

Qamhiyeh

Geismar

Pöttgen

et al. 2012

J Applied Clin Med Phys

View full text Add to dashboard Cite

show abstract

“…The percentage of time for the prostate to shift

> 3 mm

and

> 5 mm

in our work was 10.7% and 1.6% for both intact prostate and postprostatectomy patients, respectively, which was slightly less than the percentages reported by Li et al (19) based on 775 Calypso records of 105 patients (13.4% and 1.8%, respectively). Other techniques 9 , 11 , 14 , 15 have been used to investigate intrafractional prostate motion and most reported intrafraction motion with respect to maximum displacements and their standard deviations within a small number of patients. For instance, Padhani et al (14) reported

\geq 5 mm

anterior–posterior displacements in 29% of 7 min cine MR scans for 55 patients, and Malone et al (15) reported

\geq 4 mm

vertical displacements in 8% and

\geq 4 mm

longitudinal displacements in 23% of the fractions for 28 patients, using fluoroscopy and implanted markers.…”

Section: Discussionmentioning

confidence: 99%

Intrafractional prostate motion during external beam radiotherapy monitored by a real‐time target localization system

Chen

et al. 2015

J Applied Clin Med Phys

View full text Add to dashboard Cite

This paper investigates the clinical significance of real‐time monitoring of intrafractional prostate motion during external beam radiotherapy using a commercial 4D localization system. Intrafractional prostate motion was tracked during 8,660 treatment fractions for 236 patients. The following statistics were analyzed: 1) the percentage of fractions in which the prostate shifted 2−7 mm for a certain duration; 2) the proportion of the entire tracking time during which the prostate shifted 2−7 mm; and 3) the proportion of each minute in which the shift exceeded 2−7 mm. The ten patients exhibiting maximum intrafractional‐motion patterns were analyzed separately. Our results showed that the percentage of fractions in which the prostate shifted by >2,3,5,and 7 mm off the baseline in any direction for >30 normals was 56.8%, 27.2%, 4.6%, and 0.7% for intact prostate and 68.7%, 35.6%, 10.1%, and 1.8% for postprostatectomy patients, respectively. For the ten patients, these percentages were 91.3%, 72.4%, 36.3%, and 6%, respectively. The percentage of tracking time during which the prostate shifted >2,3,5,and 7 mm was 27.8%, 10.7%, 1.6%, and 0.3%, respectively, and it was 56.2%, 33.7%, 11.2%, and 2.1%, respectively, for the ten patients. The percentage of tracking time for a >3 mm posterior motion was four to five times higher than that in other directions. For treatments completed in 5 min (VMAT) and 10 min (IMRT), the proportion for the prostate to shift by >3 mm was 4% and 12%, respectively. Although intrafractional prostate motion was generally small, caution should be taken for patients who exhibit frequent large intrafractional motion. For those patients, adjustment of patient positioning may be necessary or a larger treatment margin may be used. After the initial alignment, the likelihood of prostate motion increases with time. Therefore, it is favorable to use advanced techniques (e.g., VMAT) that require less delivery time in order to reduce the treatment uncertainty resulting from intrafractional prostate motion.PACS number: 87.50.S‐, 87.53.Kn, 87.55.N‐, 87.55.ne

show abstract

“…Recent data suggests both inter-and intra-fraction prostate motion is not negligible (6)(7)(8)(9)(10)(11). Selection of planning target volume (PTV) margins must balance assurance of adequate dose delivery to the prostate with the hazard of increased dose to normal tissues (12).…”

Section: Introductionmentioning

confidence: 99%

A Practical Method of Adaptive Radiotherapy for Prostate Cancer using Real-time Electromagnetic Tracking

Olsen¹,

Noel²,

Baker³

et al. 2009

International Journal of Radiation Oncology*Biology*Physics

View full text Add to dashboard Cite

Purpose/Objectives-We have created an automated process utilizing real-time tracking data to evaluate adequacy of PTV margins in prostate cancer, allowing for a process of adaptive radiotherapy with minimal physician workload. We present an analysis of PTV adequacy and a proposed adaptive process.Materials/Methods-Tracking data was analyzed for 15 patients who underwent SMLC IMRT with uniform 5mm PTV margins for prostate cancer utilizing the Calypso® Localization System. Additional plans were generated with 0 and 3 mm margins. A custom software application utilizing the planned dose distribution and structure location from CT simulation was developed to evaluate the dosimetric impact to the target due to motion. The dose delivered to the prostate was calculated for the initial 3, 5, and 10 fractions, and for the entire treatment. Treatment was accepted as adequate if minimum delivered prostate dose (D min ) was at least 98% of the planned D min . Conclusions-Our adaptive process successfully utilized real-time tracking data to predict the need for PTV modifications, without the added burden of physician contouring and image analysis. Our methods are applicable to other utilizations of real-time tracking, including hypofractionated treatment. Results-For

show abstract

Intrafraction Motion of the Prostate During External-Beam Radiation Therapy: Analysis of 427 Patients with Implanted Fiducial Markers

Cited by 185 publications

References 26 publications

The effects of motion on the dose distribution of proton radiotherapy for prostate cancer

The effects of motion on the dose distribution of proton radiotherapy for prostate cancer

Intrafractional prostate motion during external beam radiotherapy monitored by a real‐time target localization system

A Practical Method of Adaptive Radiotherapy for Prostate Cancer using Real-time Electromagnetic Tracking

Contact Info

Product

Resources

About