Comparison of three-dimensional conformal irradiation techniques for prostate cancer using a low-energy (6 MV) photon beam

2010 ◽  
Vol 10 (2) ◽  
pp. 91-101
Author(s):  
Christina Armpilia ◽  
Christos Antypas ◽  
Anna Zygogianni ◽  
Myrsini Balafouta ◽  
John Kouvaris ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Treatment Plan ◽  
Three Dimensional ◽  
Low Energy ◽  
Photon Beam ◽  
High Dose ◽  
Prostate Radiotherapy ◽  
Energy Beam ◽  
Dose Volume Histograms ◽  
Femoral Heads

AbstractPurpose: To evaluate composite coplanar and non-coplanar three-dimensional conformal techniques (3D-CRT) for external-beam prostate radiotherapy using a low-energy (6 MV) photon beam.Methods and Materials: For treatment-planning purposes, three different planning target volumes (PTV) were defined for ten patients with prostate cancer and as follows: PTV1 (pelvis), PTV2 (prostate + seminal vesicles + 1 cm margin) and PTV3 (prostate + 1 cm margin). Conformal techniques of 2, 3, 4, 5 (coplanar) and 6 (non-coplanar) field techniques have been considered and combined to produce five different plan combinations (i.e. techniques A, B, C, D and E). Treatment plans were generated with a prescription dose of 75 Gy to PTV3, 65 Gy to PTV2 and 45 Gy to PTV1 and were assessed on the basis of 3D dose distributions and dose-volume histograms (DVHs). Normal tissue-dose constraints for the relevant organs at risk (OARs), that is, rectum, bladder and femoral heads, were also considered.Results: Findings show that all five treatment-plan combinations result in adequate PTV coverage and acceptable OAR irradiated volumes. The greatest rectal spacing in the high-dose region is achieved by technique C; all techniques achieve this, except for technique A, and give approximately the same fraction of volume (of rectum) that receives a dose of 50 Gy (V50) and 60 Gy (V60). When considering the bladder, techniques B, D and E give the best bladder sparing with small absolute differences, whereas technique A results in the lowest dose for femoral heads. Technique E appears to give the best compromise for all three considered OARs, provided the PTV is adequately covered.Conclusions: Even though the optimum photon-beam energy for conformal prostate radiotherapy is greater than 10 MV, our study shows that a good sparing of OAR can be achieved even with a lower-energy beam (6 MV) and the appropriate plan combination and that the dose to prostate can be as high as 75 Gy.

scholarly journals A Three-Dimensional-Printed Patient-Specific Phantom for External Beam Radiation Therapy of Prostate Cancer

2018 ◽  
Vol 1 (4) ◽  
Author(s):  
Christopher L. Lee ◽  
Max C. Dietrich ◽  
Uma G. Desai ◽  
Ankur Das ◽  
Suhong Yu ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Treatment Plan ◽  
Ejaculatory Duct ◽  
Three Dimensional ◽  
External Beam Radiation Therapy ◽  
External Beam Radiation ◽  
Patient Specific ◽  
External Beam ◽  
Beam Radiation

This paper presents the design evolution, fabrication, and testing of a novel patient and organ-specific, three-dimensional (3D)-printed phantom for external beam radiation therapy (EBRT) of prostate cancer. In contrast to those found in current practice, this phantom can be used to plan and validate treatment tailored to an individual patient. It contains a model of the prostate gland with a dominant intraprostatic lesion (DIL), seminal vesicles, urethra, ejaculatory duct, neurovascular bundles, rectal wall, and penile bulb generated from a series of combined T2-weighted/dynamic contrast-enhanced magnetic resonance (MR) images. The iterative process for designing the phantom based on user interaction and evaluation is described. Using the CyberKnife System at Boston Medical Center, a treatment plan was successfully created and delivered. Dosage delivery results were validated through gamma index calculations based on radiochromic film measurements which yielded a 99.8% passing rate. This phantom is a demonstration of a methodology for incorporating high-contrast MR imaging into computed-tomography-based radiotherapy treatment planning; moreover, it can be used to perform quality assurance (QA).

Results of a Phase II Study Using Estramustine Phosphate and Vinblastine in Combination With High-Dose Three-Dimensional Conformal Radiotherapy for Patients With Locally Advanced Prostate Cancer

2000 ◽  
Vol 18 (9) ◽  
pp. 1936-1941 ◽  
Author(s):  
Michael J. Zelefsky ◽  
William K. Kelly ◽  
Howard I. Scher ◽  
Henry Lee ◽  
Tracy Smart ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Gleason Score ◽  
Three Dimensional ◽  
Conformal Radiotherapy ◽  
High Dose ◽  
Estramustine Phosphate ◽  
Risk Prostate Cancer ◽  
Grade 3 ◽  
Three Dimensional Conformal Radiotherapy ◽  
3D Crt

PURPOSE: To assess the feasibility and tolerance of neoadjuvant and concomitant estramustine phosphate and vinblastine (EV) with high-dose three-dimensional conformal radiotherapy (3D-CRT) for patients with unfavorable-risk prostate cancer. PATIENTS AND METHODS: Twenty-seven patients with unfavorable-risk prostate cancer were enrolled onto a prospective study to determine the feasibility of combining EV with 3D-CRT. Patients were eligible if any of the following requirements were satisfied: (1) Gleason score ≥ 8 and prostate-specific antigen (PSA) > 10 ng/mL; (2) Gleason score of 7 and PSA > 20 ng/mL; (3) clinical stage T3N0M0 disease with PSA > 20 ng/mL; (4) any patient with T4N0M0 disease; or (5) patients with TXN1MO disease. Therapy consisted of three 8-week cycles of EV and 8 weeks of 3D-CRT. Estramustine phosphate was given orally beginning on week 1 and continued until the completion of 3D-CRT. Each 8-week cycle of vinblastine consisted of 6 weekly intravenous injections followed by a 2-week rest period. Radiation therapy was administered using a three-dimensional conformal approach to a prescription dose of 75.6 Gy. The median follow-up was 26 months (range, 6 to 40 months). RESULTS: Twenty-three (85%) of 27 patients completed the entire course of therapy and were assessable for toxicities and biochemical outcome. Two patients (7%) developed grade 3 hematologic toxicity that resolved, and two patients (7%) developed grade 3 hepatoxicity, manifesting as persistent elevation of serum transaminase levels, necessitating discontinuation of the chemotherapy and withdrawal from the treatment program. The most prominent adverse effects from this regimen were mild to moderate (grade 1 to 2) nausea and fatigue related to estramustine. Mild peripheral edema was seen in 15% of patients and was treated with diuresis. 3D-CRT was tolerated well in these patients. Medications were required for relief of acute grade 2 rectal (gastrointestinal [GI]) and urinary (genitourinary [GU]) symptoms in 35% and 48% of patients, respectively. Three patients developed acute grade 3 GU toxicities. The 2-year actuarial likelihood of late grade 2 GI toxicity was 20%. No late grade 3 or 4 GI toxicities were observed. The 2-year actuarial likelihoods of late grade 2 and 3 GU toxicities were 25% and 12%, respectively. No grade 4 GU toxicity was observed. CONCLUSION: Neoadjuvant and concomitant EV with high-dose 3D-CRT is well tolerated in patients with unfavorable-risk prostate cancer. Although the incidence of modest (grade 2) late GI and GU toxicities seem to be increased compared with 3D-CRT alone or in combination with androgen ablation therapy, no severe toxicities were encountered with this regimen.

scholarly journals Stereotactic Radiosurgery Associated Neurotoxicity

2003 ◽  
Vol 2 (2) ◽  
pp. 147-151 ◽  
Author(s):  
William H. St. Clair ◽  
Curtis A. Given
Keyword(s):  
Stereotactic Radiosurgery ◽  
Therapeutic Option ◽  
Treatment Plan ◽  
Three Dimensional ◽  
Reference Points ◽  
Therapeutic Modality ◽  
High Dose ◽  
Lesion Volume ◽  
Three Dimensional Mapping ◽  
Effective Therapeutic Option

Stereotactic radiosurgery (SRS) is an evolving therapeutic modality for well demarcated intracranial lesions. Since the inception of stereotactic radiosurgery the types of parenchymal CNS lesions addressed by this mode of treatment has increased. All modern stereotactic radiosurgical procedures employ several common features. Patients are fitted with a stereotactic head frame or fiducial markers followed by radiographic imaging which allows for external reference points and three-dimensional mapping of the intracranial lesion. Armed with this information a highly conformal treatment plan is developed to deliver a high dose of radiation to a sharply defined target, with rapid dose fall-off outside the lesion volume. While an extremely effective therapeutic option, SRS is not without risk of neurotoxicity, with radiation necrosis being the most commonly recognized complication. The neurotoxic effects of SRS are reviewed and discussed.

Dose-escalated adaptive image-guided radiotherapy versus high-dose-rate brachytherapy monotherapy for low-risk prostate cancer.

2013 ◽  
Vol 31 (6_suppl) ◽  
pp. 145-145
Author(s):  
Ovidiu Marina ◽  
Daniel J. Krauss ◽  
Donald Brabbins ◽  
Michelle Wallace ◽  
Alvaro A Martinez ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Treatment Plan ◽  
Target Volume ◽  
Low Risk ◽  
Definitive Treatment ◽  
Patient Specific ◽  
High Dose ◽  
Treatment Type ◽  
Risk Prostate Cancer ◽  
Low Risk Prostate Cancer

145 Background: Both IGRT and HDR are used for definitive treatment of low-risk prostate. No comparative study of these contemporary modalities exists. Methods: Charts for patients with low-risk prostate cancer by NCCN criteria treated 1999-2012 were reviewed. For IGRT, the clinical target volume (CTV) included the prostate and proximal seminal vesicles. A CT-based, off-line adaptive treatment plan was made with a patient-specific confidence-limited planning target volume (cl-PTV) based on the planning plus four additional daily CT scans. Overall survival (OS) was calculated by the Kaplan-Meier method (log-rank test), with Cox regression for uni- and multi-variate analysis. Cumulative incidence (Gray’s test), with competing risks analysis (Fine and Gray) were used for biochemical control (BC) and freedom from local recurrence (FFLR). Results: There were 598 IGRT and 399 HDR patients (see Table), with a median follow-up of 6.1 and 3.6 years, respectively (p<0.001). The median prescribed IGRT dose was 75.6 Gy (range 73.8-79.2). HDR doses were 24 Gy (n=126) or 27 Gy (n=151) in 2 fractions, or 36 Gy (n=3) or 38 Gy (n=335) in 4 fractions. Five- and 10-year BC was 99% and 94% for IGRT and 98% and 95% for HDR (p=0.77); FFLR was 100% and 99% for both (p=0.89); and OS was 95% and 75% for IGRT and 97% and 85% for HDR (p=0.04). On multivariate analysis, predictors (p<0.10) for OS were age (p<0.001) and PNI (p=0.04); for LR, PPC (p=0.01); and for BC, a trend for PSA (p=0.08). Treatment type was not a predictor of OS, BC or FFLR (p>0.5). Conclusions: Both dose- escalated IGRT and HDR monotherapy yield similarly excellent outcomes for low-risk prostate cancer. Our experience supports the continued use of brachytherapy as monotherapy in low-risk prostate cancer. [Table: see text]

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