Advantage of three-dimensional treatment planning for localized radiotherapy of early stage prostatic cancer.

TY - JOUR

T1 - Advantage of three-dimensional treatment planning for localized radiotherapy of early stage prostatic cancer.

AU - Wiegel, T

AU - Schmidt, R

AU - Krüll, Andreas

AU - Schwarz, R

AU - Sommer, K

AU - Hübener, K H

PY - 1992

Y1 - 1992

N2 - Conventional two-dimensional (2-d) treatment planning was compared to three-dimensional (3-d) treatment planning for patients with prostatic carcinoma. Both types of treatment planning were performed for all ten patients with five fixed fields. In 3-d planning we used irregular shaped fields. For further evaluation we performed conventional planning in rotation technique in two patients. The target volume included prostate, seminal vesicles and a surrounding security margin of 2 cm. Using the MPR-version of the MEVAPLAN planning system, the three-dimensional dose calculations were performed. For the volumes of interest (VOI's) we discussed quality of the dose distribution concerning homogeneity in the target volume and isodose distribution in the organs at risk, which are the rectum and the urinary bladder. We defined the tumor encompassing reference isodose (ca. 95%) for the calculation of the involved rectum- and bladder volume. Using the five-field technique our results show a reduction of the radiation related rectum- and bladder volume concerning the tumor encompassing reference isodose (ca. 95%) for the rectum in between 9.5 and 36.6% (median: 19%, n = 10) and for the urinary bladder in between 15.7 and 47.8% (median: 28%, n = 10). Calculated for 80% of the reference isodose the difference for the rectum was 15.7 to 31.3% (median: 23%) and for the urinary bladder 24.5 to 56.7% (median: 42%). A significant reduction of radiation related side-effects concerning rectum and urinary bladder can be expected by a reduction of volume involvement and a consecutive dosage limitation.

AB - Conventional two-dimensional (2-d) treatment planning was compared to three-dimensional (3-d) treatment planning for patients with prostatic carcinoma. Both types of treatment planning were performed for all ten patients with five fixed fields. In 3-d planning we used irregular shaped fields. For further evaluation we performed conventional planning in rotation technique in two patients. The target volume included prostate, seminal vesicles and a surrounding security margin of 2 cm. Using the MPR-version of the MEVAPLAN planning system, the three-dimensional dose calculations were performed. For the volumes of interest (VOI's) we discussed quality of the dose distribution concerning homogeneity in the target volume and isodose distribution in the organs at risk, which are the rectum and the urinary bladder. We defined the tumor encompassing reference isodose (ca. 95%) for the calculation of the involved rectum- and bladder volume. Using the five-field technique our results show a reduction of the radiation related rectum- and bladder volume concerning the tumor encompassing reference isodose (ca. 95%) for the rectum in between 9.5 and 36.6% (median: 19%, n = 10) and for the urinary bladder in between 15.7 and 47.8% (median: 28%, n = 10). Calculated for 80% of the reference isodose the difference for the rectum was 15.7 to 31.3% (median: 23%) and for the urinary bladder 24.5 to 56.7% (median: 42%). A significant reduction of radiation related side-effects concerning rectum and urinary bladder can be expected by a reduction of volume involvement and a consecutive dosage limitation.

KW - Humans

KW - Male

KW - Radiotherapy Dosage

KW - Neoplasm Staging

KW - Tomography, X-Ray Computed/methods

KW - Radiotherapy Planning, Computer-Assisted/methods

KW - Rectum/radiography

KW - Urinary Bladder/radiography

KW - Prostatic Neoplasms/pathology/radiography/radiotherapy

KW - Seminal Vesicles/radiography

KW - Humans

KW - Male

KW - Radiotherapy Dosage

KW - Neoplasm Staging

KW - Tomography, X-Ray Computed/methods

KW - Radiotherapy Planning, Computer-Assisted/methods

KW - Rectum/radiography

KW - Urinary Bladder/radiography

KW - Prostatic Neoplasms/pathology/radiography/radiotherapy

KW - Seminal Vesicles/radiography

M3 - SCORING: Journal article

VL - 168

SP - 692

EP - 697

JO - STRAHLENTHER ONKOL

JF - STRAHLENTHER ONKOL

SN - 0179-7158

IS - 12

M1 - 12

ER -