SU‐GG‐T‐425: Radiobiologically Quantified Treatment Setup Uncertainties Based On Megavoltage (MV) CT Imaging

G. Swanson; C. Shi; P. Mavroidis; S. Stathakis; F. su; R. Ramer; V. Sarkar; B. Ferreira; G. Komisopoulos; D. Giantsoudi; N. Papanikolaou

doi:10.1118/1.2962173

SU‐GG‐T‐425: Radiobiologically Quantified Treatment Setup Uncertainties Based On Megavoltage (MV) CT Imaging

G. Swanson, C. Shi, P. Mavroidis, S. Stathakis, F. su, R. Ramer, V. Sarkar, B. Ferreira, G. Komisopoulos, D. Giantsoudi, N. Papanikolaou

Research output: Contribution to journal › Article › peer-review

Abstract

Purpose: To evaluate and compare the expected effectiveness of the planned and delivered dose distributions in prostate cancer radiotherapy. The average setup uncertainties were determined by using the on‐board megavoltage computed tomography (MVCT) capabilities of the tomotherapy HiArt unit. Method and Materials: Co‐registrations between daily MVCT and planning CT were used. Before the delivery of each treatment an MVCT image was acquired. The therapists registered the MVCT image with the planning kilovoltage computed tomography (kVCT) images. The registration criteria were based on bony anatomy and contoured regions of interest. For a typical prostate cancer patient the dose distributions of the Helical Tomotherapy plan and that of the average shifted delivery registration were used. The dose distributions were compared based on dosimetric criteria and the biologically effective uniform dose (BEUD) together with the complication‐free tumor control probability (P₊). Results: The average shifts that were observed are 10.7 mm for the vertical, 4.0 mm for the longitudinal and 0.5 mm for the lateral directions, respectively. At the optimum dose levels of the planned and delivered dose distributions, the P₊ values are 84.7% and 84.0%, respectively. The total control probabilities, P_B are 93.0% and 92.9%, whereas the total complication probabilities, P_I are 8.3% and 8.9%. More specifically, the response probabilities of the different tissues are 95.6% and 95.5% for the GTV, 97.4% and 97.3% for the seminal vesicles, 0.8% and 0.7% for bladder and 7.6% and 8.3% for rectum. Conclusion: It is shown that the intra‐fraction movement of tumors can be reduced by using the MVCT co‐registration. This appears to be a powerful tool, which can result in improved sparing of critical structures, while delivering high doses to the target. The use of P₊ — BEUD diagrams to compare similar treatment plans may show that in radiobiological terms they may be quite different.

Original language	English (US)
Pages (from-to)	2822
Number of pages	1
Journal	Medical physics
Volume	35
Issue number	6
DOIs	https://doi.org/10.1118/1.2962173
State	Published - Jun 2008
Externally published	Yes

ASJC Scopus subject areas

Biophysics
Radiology Nuclear Medicine and imaging

Access to Document

10.1118/1.2962173

Cite this

@article{7117d172c57c4b5887bd94cee5d1346e,

title = "SU‐GG‐T‐425: Radiobiologically Quantified Treatment Setup Uncertainties Based On Megavoltage (MV) CT Imaging",

abstract = "Purpose: To evaluate and compare the expected effectiveness of the planned and delivered dose distributions in prostate cancer radiotherapy. The average setup uncertainties were determined by using the on‐board megavoltage computed tomography (MVCT) capabilities of the tomotherapy HiArt unit. Method and Materials: Co‐registrations between daily MVCT and planning CT were used. Before the delivery of each treatment an MVCT image was acquired. The therapists registered the MVCT image with the planning kilovoltage computed tomography (kVCT) images. The registration criteria were based on bony anatomy and contoured regions of interest. For a typical prostate cancer patient the dose distributions of the Helical Tomotherapy plan and that of the average shifted delivery registration were used. The dose distributions were compared based on dosimetric criteria and the biologically effective uniform dose (BEUD) together with the complication‐free tumor control probability (P+). Results: The average shifts that were observed are 10.7 mm for the vertical, 4.0 mm for the longitudinal and 0.5 mm for the lateral directions, respectively. At the optimum dose levels of the planned and delivered dose distributions, the P+ values are 84.7% and 84.0%, respectively. The total control probabilities, PB are 93.0% and 92.9%, whereas the total complication probabilities, PI are 8.3% and 8.9%. More specifically, the response probabilities of the different tissues are 95.6% and 95.5% for the GTV, 97.4% and 97.3% for the seminal vesicles, 0.8% and 0.7% for bladder and 7.6% and 8.3% for rectum. Conclusion: It is shown that the intra‐fraction movement of tumors can be reduced by using the MVCT co‐registration. This appears to be a powerful tool, which can result in improved sparing of critical structures, while delivering high doses to the target. The use of P+ — BEUD diagrams to compare similar treatment plans may show that in radiobiological terms they may be quite different.",

author = "G. Swanson and C. Shi and P. Mavroidis and S. Stathakis and F. su and R. Ramer and V. Sarkar and B. Ferreira and G. Komisopoulos and D. Giantsoudi and N. Papanikolaou",

year = "2008",

month = jun,

doi = "10.1118/1.2962173",

language = "English (US)",

volume = "35",

pages = "2822",

journal = "Medical physics",

issn = "0094-2405",

publisher = "AAPM - American Association of Physicists in Medicine",

number = "6",

}

TY - JOUR

T1 - SU‐GG‐T‐425

T2 - Radiobiologically Quantified Treatment Setup Uncertainties Based On Megavoltage (MV) CT Imaging

AU - Swanson, G.

AU - Shi, C.

AU - Mavroidis, P.

AU - Stathakis, S.

AU - su, F.

AU - Ramer, R.

AU - Sarkar, V.

AU - Ferreira, B.

AU - Komisopoulos, G.

AU - Giantsoudi, D.

AU - Papanikolaou, N.

PY - 2008/6

Y1 - 2008/6

N2 - Purpose: To evaluate and compare the expected effectiveness of the planned and delivered dose distributions in prostate cancer radiotherapy. The average setup uncertainties were determined by using the on‐board megavoltage computed tomography (MVCT) capabilities of the tomotherapy HiArt unit. Method and Materials: Co‐registrations between daily MVCT and planning CT were used. Before the delivery of each treatment an MVCT image was acquired. The therapists registered the MVCT image with the planning kilovoltage computed tomography (kVCT) images. The registration criteria were based on bony anatomy and contoured regions of interest. For a typical prostate cancer patient the dose distributions of the Helical Tomotherapy plan and that of the average shifted delivery registration were used. The dose distributions were compared based on dosimetric criteria and the biologically effective uniform dose (BEUD) together with the complication‐free tumor control probability (P+). Results: The average shifts that were observed are 10.7 mm for the vertical, 4.0 mm for the longitudinal and 0.5 mm for the lateral directions, respectively. At the optimum dose levels of the planned and delivered dose distributions, the P+ values are 84.7% and 84.0%, respectively. The total control probabilities, PB are 93.0% and 92.9%, whereas the total complication probabilities, PI are 8.3% and 8.9%. More specifically, the response probabilities of the different tissues are 95.6% and 95.5% for the GTV, 97.4% and 97.3% for the seminal vesicles, 0.8% and 0.7% for bladder and 7.6% and 8.3% for rectum. Conclusion: It is shown that the intra‐fraction movement of tumors can be reduced by using the MVCT co‐registration. This appears to be a powerful tool, which can result in improved sparing of critical structures, while delivering high doses to the target. The use of P+ — BEUD diagrams to compare similar treatment plans may show that in radiobiological terms they may be quite different.

AB - Purpose: To evaluate and compare the expected effectiveness of the planned and delivered dose distributions in prostate cancer radiotherapy. The average setup uncertainties were determined by using the on‐board megavoltage computed tomography (MVCT) capabilities of the tomotherapy HiArt unit. Method and Materials: Co‐registrations between daily MVCT and planning CT were used. Before the delivery of each treatment an MVCT image was acquired. The therapists registered the MVCT image with the planning kilovoltage computed tomography (kVCT) images. The registration criteria were based on bony anatomy and contoured regions of interest. For a typical prostate cancer patient the dose distributions of the Helical Tomotherapy plan and that of the average shifted delivery registration were used. The dose distributions were compared based on dosimetric criteria and the biologically effective uniform dose (BEUD) together with the complication‐free tumor control probability (P+). Results: The average shifts that were observed are 10.7 mm for the vertical, 4.0 mm for the longitudinal and 0.5 mm for the lateral directions, respectively. At the optimum dose levels of the planned and delivered dose distributions, the P+ values are 84.7% and 84.0%, respectively. The total control probabilities, PB are 93.0% and 92.9%, whereas the total complication probabilities, PI are 8.3% and 8.9%. More specifically, the response probabilities of the different tissues are 95.6% and 95.5% for the GTV, 97.4% and 97.3% for the seminal vesicles, 0.8% and 0.7% for bladder and 7.6% and 8.3% for rectum. Conclusion: It is shown that the intra‐fraction movement of tumors can be reduced by using the MVCT co‐registration. This appears to be a powerful tool, which can result in improved sparing of critical structures, while delivering high doses to the target. The use of P+ — BEUD diagrams to compare similar treatment plans may show that in radiobiological terms they may be quite different.

UR - http://www.scopus.com/inward/record.url?scp=85024781206&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85024781206&partnerID=8YFLogxK

U2 - 10.1118/1.2962173

DO - 10.1118/1.2962173

M3 - Article

AN - SCOPUS:85024781206

SN - 0094-2405

VL - 35

SP - 2822

JO - Medical physics

JF - Medical physics

IS - 6

ER -

SU‐GG‐T‐425: Radiobiologically Quantified Treatment Setup Uncertainties Based On Megavoltage (MV) CT Imaging

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this