SU‐FF‐T‐176: Rectal and Bladder Dose in Relationship to PTV Percentage Coverage in Prostate IMRT

J. Yang, T. Liu, C. Yang, R. Jennelle, A. Chen, L. do, Richard K Valicenti, J. Purdy

Research output: Contribution to journalArticle

Abstract

Purpose: To study the relationship between percentage coverage of planning target volume (PTV) in prostate cancer IMRT and dose received by normal critical structures Method and Materials: Five patients with early stage prostate cancer were selected for this retrospective planning study. For 4 of 5 patients, PTV contains clinical target volume (CTV), which is the prostate gland, plus 0.8 cm uniform margin. For the fifth patient, PTV is formed by expanding CTV (prostate plus 1 cm proximal seminal vesicle) with 0.8 cm uniform margin. The prescription is 74 Gy for the first four patients and 79.2 Gy (last patient) prescribed to 95% iso dose line and dose normalization is to isocenter. For each patient, seven different plans were generated using Varian Eclipse treatment planning system version 8.1 for 18 MV photon beams from Varian 2100C: one 6‐field conformal plan and six 7‐field IMRT plans with PTV volume coverage raging from 99.5% to 95%. IMRT plans were optimized by iterations to reach the targeted coverage of PTV. Results: A linear correlation between the volume receiving 70 Gy in percentage or cc and PTV volume coverage from 99.5% to 95% has been found for both balder and rectum with R2 better than 0.95 for bladder and 0.91 for rectum for the first four patients. A generalized relationship can be written as [formula omitted] (1). All patients have a similar linear slope for bladder (average slope is 0.867±0.083 (SD)) and a slightly different slope for rectum (average slope is 0.545±0.230 (SD)). In equation (1), interception b is dependant of structure volume (bladder and rectum). Conclusions: Volume received 70 Gy by bladder and rectum in IMRT plans for prostate as CTV may have a linear relationship with PTV coverage ranging from 99.5% to 95%. One may use this relationship to guide in treatment planning process.

Original languageEnglish (US)
Pages (from-to)2560-2561
Number of pages2
JournalMedical Physics
Volume36
Issue number6
DOIs
StatePublished - Jan 1 2009

Fingerprint

Prostate
Urinary Bladder
Rectum
Prostatic Neoplasms
Seminal Vesicles
Photons
Prescriptions
Retrospective Studies
Therapeutics

ASJC Scopus subject areas

  • Biophysics
  • Radiology Nuclear Medicine and imaging

Cite this

Yang, J., Liu, T., Yang, C., Jennelle, R., Chen, A., do, L., ... Purdy, J. (2009). SU‐FF‐T‐176: Rectal and Bladder Dose in Relationship to PTV Percentage Coverage in Prostate IMRT. Medical Physics, 36(6), 2560-2561. https://doi.org/10.1118/1.3181651

SU‐FF‐T‐176 : Rectal and Bladder Dose in Relationship to PTV Percentage Coverage in Prostate IMRT. / Yang, J.; Liu, T.; Yang, C.; Jennelle, R.; Chen, A.; do, L.; Valicenti, Richard K; Purdy, J.

In: Medical Physics, Vol. 36, No. 6, 01.01.2009, p. 2560-2561.

Research output: Contribution to journalArticle

Yang, J. ; Liu, T. ; Yang, C. ; Jennelle, R. ; Chen, A. ; do, L. ; Valicenti, Richard K ; Purdy, J. / SU‐FF‐T‐176 : Rectal and Bladder Dose in Relationship to PTV Percentage Coverage in Prostate IMRT. In: Medical Physics. 2009 ; Vol. 36, No. 6. pp. 2560-2561.
@article{82aa5c3715594de4b28d59af1f403498,
title = "SU‐FF‐T‐176: Rectal and Bladder Dose in Relationship to PTV Percentage Coverage in Prostate IMRT",
abstract = "Purpose: To study the relationship between percentage coverage of planning target volume (PTV) in prostate cancer IMRT and dose received by normal critical structures Method and Materials: Five patients with early stage prostate cancer were selected for this retrospective planning study. For 4 of 5 patients, PTV contains clinical target volume (CTV), which is the prostate gland, plus 0.8 cm uniform margin. For the fifth patient, PTV is formed by expanding CTV (prostate plus 1 cm proximal seminal vesicle) with 0.8 cm uniform margin. The prescription is 74 Gy for the first four patients and 79.2 Gy (last patient) prescribed to 95{\%} iso dose line and dose normalization is to isocenter. For each patient, seven different plans were generated using Varian Eclipse treatment planning system version 8.1 for 18 MV photon beams from Varian 2100C: one 6‐field conformal plan and six 7‐field IMRT plans with PTV volume coverage raging from 99.5{\%} to 95{\%}. IMRT plans were optimized by iterations to reach the targeted coverage of PTV. Results: A linear correlation between the volume receiving 70 Gy in percentage or cc and PTV volume coverage from 99.5{\%} to 95{\%} has been found for both balder and rectum with R2 better than 0.95 for bladder and 0.91 for rectum for the first four patients. A generalized relationship can be written as [formula omitted] (1). All patients have a similar linear slope for bladder (average slope is 0.867±0.083 (SD)) and a slightly different slope for rectum (average slope is 0.545±0.230 (SD)). In equation (1), interception b is dependant of structure volume (bladder and rectum). Conclusions: Volume received 70 Gy by bladder and rectum in IMRT plans for prostate as CTV may have a linear relationship with PTV coverage ranging from 99.5{\%} to 95{\%}. One may use this relationship to guide in treatment planning process.",
author = "J. Yang and T. Liu and C. Yang and R. Jennelle and A. Chen and L. do and Valicenti, {Richard K} and J. Purdy",
year = "2009",
month = "1",
day = "1",
doi = "10.1118/1.3181651",
language = "English (US)",
volume = "36",
pages = "2560--2561",
journal = "Medical Physics",
issn = "0094-2405",
publisher = "AAPM - American Association of Physicists in Medicine",
number = "6",

}

TY - JOUR

T1 - SU‐FF‐T‐176

T2 - Rectal and Bladder Dose in Relationship to PTV Percentage Coverage in Prostate IMRT

AU - Yang, J.

AU - Liu, T.

AU - Yang, C.

AU - Jennelle, R.

AU - Chen, A.

AU - do, L.

AU - Valicenti, Richard K

AU - Purdy, J.

PY - 2009/1/1

Y1 - 2009/1/1

N2 - Purpose: To study the relationship between percentage coverage of planning target volume (PTV) in prostate cancer IMRT and dose received by normal critical structures Method and Materials: Five patients with early stage prostate cancer were selected for this retrospective planning study. For 4 of 5 patients, PTV contains clinical target volume (CTV), which is the prostate gland, plus 0.8 cm uniform margin. For the fifth patient, PTV is formed by expanding CTV (prostate plus 1 cm proximal seminal vesicle) with 0.8 cm uniform margin. The prescription is 74 Gy for the first four patients and 79.2 Gy (last patient) prescribed to 95% iso dose line and dose normalization is to isocenter. For each patient, seven different plans were generated using Varian Eclipse treatment planning system version 8.1 for 18 MV photon beams from Varian 2100C: one 6‐field conformal plan and six 7‐field IMRT plans with PTV volume coverage raging from 99.5% to 95%. IMRT plans were optimized by iterations to reach the targeted coverage of PTV. Results: A linear correlation between the volume receiving 70 Gy in percentage or cc and PTV volume coverage from 99.5% to 95% has been found for both balder and rectum with R2 better than 0.95 for bladder and 0.91 for rectum for the first four patients. A generalized relationship can be written as [formula omitted] (1). All patients have a similar linear slope for bladder (average slope is 0.867±0.083 (SD)) and a slightly different slope for rectum (average slope is 0.545±0.230 (SD)). In equation (1), interception b is dependant of structure volume (bladder and rectum). Conclusions: Volume received 70 Gy by bladder and rectum in IMRT plans for prostate as CTV may have a linear relationship with PTV coverage ranging from 99.5% to 95%. One may use this relationship to guide in treatment planning process.

AB - Purpose: To study the relationship between percentage coverage of planning target volume (PTV) in prostate cancer IMRT and dose received by normal critical structures Method and Materials: Five patients with early stage prostate cancer were selected for this retrospective planning study. For 4 of 5 patients, PTV contains clinical target volume (CTV), which is the prostate gland, plus 0.8 cm uniform margin. For the fifth patient, PTV is formed by expanding CTV (prostate plus 1 cm proximal seminal vesicle) with 0.8 cm uniform margin. The prescription is 74 Gy for the first four patients and 79.2 Gy (last patient) prescribed to 95% iso dose line and dose normalization is to isocenter. For each patient, seven different plans were generated using Varian Eclipse treatment planning system version 8.1 for 18 MV photon beams from Varian 2100C: one 6‐field conformal plan and six 7‐field IMRT plans with PTV volume coverage raging from 99.5% to 95%. IMRT plans were optimized by iterations to reach the targeted coverage of PTV. Results: A linear correlation between the volume receiving 70 Gy in percentage or cc and PTV volume coverage from 99.5% to 95% has been found for both balder and rectum with R2 better than 0.95 for bladder and 0.91 for rectum for the first four patients. A generalized relationship can be written as [formula omitted] (1). All patients have a similar linear slope for bladder (average slope is 0.867±0.083 (SD)) and a slightly different slope for rectum (average slope is 0.545±0.230 (SD)). In equation (1), interception b is dependant of structure volume (bladder and rectum). Conclusions: Volume received 70 Gy by bladder and rectum in IMRT plans for prostate as CTV may have a linear relationship with PTV coverage ranging from 99.5% to 95%. One may use this relationship to guide in treatment planning process.

UR - http://www.scopus.com/inward/record.url?scp=85024785667&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85024785667&partnerID=8YFLogxK

U2 - 10.1118/1.3181651

DO - 10.1118/1.3181651

M3 - Article

AN - SCOPUS:85024785667

VL - 36

SP - 2560

EP - 2561

JO - Medical Physics

JF - Medical Physics

SN - 0094-2405

IS - 6

ER -