A critical evaluation of the planning target volume for 3-D conformal radiotherapy of prostate cancer

1998 ◽  
Vol 42 (1) ◽  
pp. 213-221 ◽  
Author(s):  
Alfred Tinger ◽  
Jeff M. Michalski ◽  
Abel Cheng ◽  
Daniel A. Low ◽  
Ron Zhu ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Planning Target Volume ◽  
Critical Evaluation ◽  
Conformal Radiotherapy ◽  
Target Volume

scholarly journals Dosimetric Comparison: Intensity Modulated Radiation Therapy Vs. 3D Conformal Radiotherapy In Prostate Cancer Radical Treatment

2019 ◽  
Vol 0 (0) ◽  
Author(s):  
Slavica Maric ◽  
Snezana Lukic ◽  
Milan Mijailovic ◽  
Ljiljana Tadic Latinovic ◽  
Milan Zigic ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Planning Target Volume ◽  
Intensity Modulated Radiation Therapy ◽  
Absorbed Dose ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Intensity Modulated ◽  
Radical Treatment ◽  
3D Conformal Radiotherapy

Abstract 3D - Conformal Radiotherapy (3DCRT) for decades was a standard technique in the prostate cancer radical radiotherapy treatment. Technological advances and implementation of an innovative radiotherapy technique - Intensity Modulated Radiation Therapy (IMRT), enable even more precise treatment of the prostate cancer patients. Intensity Modulated Radiation Therapy (IMRT) is a technological advancement in Conformal Radiotherapy which allows superior conformity and homogeneity of the absorbed dose in planning target volume with maximal sparing organs of risk. This technique gives us possibility to escalate the radiotherapy dose, prerequisite for the adequate local tumor control. Evaluation of dosimetric parameters 3DCRT vs. IMRT: the homogeneity index, the conformity index, parameters of absorbed dose in planning target volume, dose volume constraints for organs of risk shows that IMRT is an optimal technique in the prostate cancer radical treatment.

scholarly journals Rectal spacer hydrogel in 1.5T MR-guided and daily adapted SBRT for prostate cancer: dosimetric analysis and preliminary patient-reported outcomes

2021 ◽  
Vol 94 (1117) ◽  
pp. 20200848
Author(s):  
Filippo Alongi ◽  
Michele Rigo ◽  
Vanessa Figlia ◽  
Francesco Cuccia ◽  
Niccolò Giaj-Levra ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Planning Target Volume ◽  
Patient Reported Outcomes ◽  
Target Volume ◽  
Spacer Group ◽  
End Of Treatment ◽  
Patient Reported ◽  
Eortc Qlq C30 ◽  
Dosimetric Analysis ◽  
Eortc Qlq

Objective: The main aim of the current analysis was to explore the hypothetical advantages using rectal spacer during 1.5T MR-guided and daily adapted prostate cancer stereotactic body radiotherapy (SBRT) compared to a no-rectal spacer hydrogel cohort of patients. Methods: The SBRT-protocol consisted of a 35 Gy schedule delivered in 5 fractions. Herein, we present a dosimetric analysis between spacer and no-spacer patients. Furthermore, treatment tolerability and feasibility were preliminarily assessed according to clinicians-reported outcomes at the end of treatment and patient-reported outcomes measures (PROMs) in both arms. Toxicity and quality of life were assessed at baseline and after treatment using the Common Terminology Criteria for Adverse Events v. 5.0, International Prostatic Symptoms Score, ICIQ-SF, IIEF-5, and EORTC-QLQ-C30 and PR-25 questionnaires. Results: 120 plans (pre- and daily adaptive SBRT planning) were analyzed in 20 patients (10 patients in spacer group and 10 patients in no-spacer group) treated using 1.5T MR-guided adaptive SBRT. Statistically significant dosimetric advantages were observed in favor of the spacer insertion, improving the planning target volume coverage in terms of V33.2Gy >95% and planning target volume 37.5 Gy <2% mainly during daily-adapted SBRT. Also, rectum V32, V28 and V18Gy and bladder V35Gy <1 cc were significantly reduced in the spacer cohort. Concerning the PROMS, all questionnaires showed no difference between the pre- and post-SBRT evaluation in both arms, excepting the physical functioning item of EORTC QLQ-C30 questionnaire that was declined in the no-spacer group. Conclusion: These preliminary results strongly suggest the adoption of perirectal spacer due to dosimetric advantages not only for rectal sparing but also for target coverage. Longer follow-up is required to validate the clinical impact in terms of clinicians-reported toxicity and PROMs. Advances in knowledge: This the first experience reporting preliminary data concerning the potential dosimetric impact of rectal hydrogel spacer on MR-guided SBRT for prostate cancer.

a critical evaluation of internal organ immobilisation techniques

2004 ◽  
Vol 4 (2-3) ◽  
pp. 118-125
Author(s):  
p. bridge
Keyword(s):  
Clinical Target Volume ◽  
Critical Evaluation ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Organ Motion ◽  
Rectal Balloon ◽  
Breathing Control ◽  
Future Developments ◽  
The Moment ◽  
Internal Margin

this paper aims to evaluate the range of techniques available to minimise both interfraction and intrafraction errors. the main interfraction errors are due to changes in volume of the rectum and bladder. intrafraction errors are mainly due to respiration and to a lesser extent cardiac motion. there are various methods of minimising internal organ motion that attempt to permit reduction of the internal margin around the clinical target volume (ctv).techniques such as rectal balloon insertion and breathing control are evaluated to determine their role in reduction of margins for improved conformal radiotherapy. the paper concludes that rectal balloons have been shown to permit limited reduction of internal margins and morbidity levels. breathing control has not increased reproducibility, but has allowed for reduction in lung morbidity. reduction of margins can only be recommended when using breathing control in conjunction with daily ctv relocalisation.although these techniques do have a role to play at the moment, it appears that attempting to maintain a static environment within the highly mobile patient is fraught with difficulties and we must accept that there is always going to be motion. rather than attempting to control the position of the tumour, future developments such as adaptive radiotherapy and tomotherapy may account for the movement.

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