Correlation of radiation dose and impotence risk after three-dimensional conformal radiotherapy for prostate cancer: Reply by the authors

PURPOSE: Several studies have defined risk groups for predicting the outcome after external-beam radiotherapy of localized prostate cancer. However, most models formed patient risk groups, and none of these models considers radiation dose as a predictor variable. The purpose of this study was to develop a nomogram to improve the accuracy of predicting outcome after three-dimensional conformal radiotherapy. MATERIALS AND METHODS: This study was a retrospective, nonrandomized analysis of patients treated at the Memorial Sloan-Kettering Cancer Center between 1988 and 1998. Clinical parameters of the 1,042 patients included stage, biopsy Gleason score, pretreatment serum prostate-specific antigen (PSA) level, whether neoadjuvant androgen deprivation therapy was administered, and the radiation dose delivered. Biochemical (PSA) treatment failure was scored when three consecutive rises of serum PSA occurred. A nomogram, which predicts the probability of remaining free from biochemical recurrence for 5 years, was validated internally on this data set using a bootstrapping method and externally using a cohort of patients treated at the Cleveland Clinic, Cleveland, OH. RESULTS: When predicting outcomes for patients in the validation data set from the Cleveland Clinic, the nomogram had a Somers’ D rank correlation between predicted and observed failure times of 0.52. Predictions from this nomogram were more accurate (P < .0001) than the best of seven published risk stratification systems, which achieved a Somers’ D coefficient of 0.47. CONCLUSION: The development process illustrated here produced a nomogram that seems to predict more accurately than other available systems and may be useful for treatment selection by both physicians and patients.

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Risk-adapted androgen deprivation and escalated three-dimensional conformal radiotherapy for prostate cancer: Does radiation dose influence outcome of patients treated with adjuvant androgen deprivation? A GICOR study

Urologic Oncology Seminars and Original Investigations ◽

10.1016/j.urolonc.2006.05.003 ◽

2006 ◽

Vol 24 (4) ◽

pp. 375-376

Author(s):

Michael J. Zelefsky

Keyword(s):

Prostate Cancer ◽

Radiation Dose ◽

Three Dimensional ◽

Conformal Radiotherapy ◽

Androgen Deprivation ◽

Three Dimensional Conformal Radiotherapy

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Efficacy of a hydrogel spacer in three-dimensional conformal radiation therapy for prostate cancer

Japanese Journal of Clinical Oncology ◽

10.1093/jjco/hyz171 ◽

2020 ◽

Vol 50 (3) ◽

pp. 303-309 ◽

Cited By ~ 2

Author(s):

Mami Ogita ◽

Hideomi Yamashita ◽

Subaru Sawayanagi ◽

Wataru Takahashi ◽

Keiichi Nakagawa

Keyword(s):

Prostate Cancer ◽

Computed Tomography ◽

High Risk ◽

Seminal Vesicle ◽

Three Dimensional ◽

Conformal Radiotherapy ◽

Computed Tomography Scans ◽

Before And After ◽

Three Dimensional Conformal Radiotherapy ◽

Dose Constraints

Abstract Objectives We aimed to compare the dose constraints fulfillment rate of the three-dimensional conformal radiotherapy treatment plan before and after a hydrogel spacer insertion. Methods The planning computed tomography scans of 39 patients who received stereotactic body radiotherapy for prostate cancer were used. All patients inserted a hydrogel spacer and underwent computed tomography scans before and after spacer insertion. The three-dimensional conformal radiotherapy plans according to NCCN classification, low-, intermediate- and high-risk, were made for each patient. Clinical target volume included prostate and seminal vesicle 2 cm for high risk, prostate and seminal vesicle 1 cm for intermediate risk and prostate only for low risk. Three-dimensional conformal radiotherapy including a seven-field conformal technique with 76 Gy in 38 fractions. Dose constraints for rectum and bladder were V70 Gy ≤ 15%, V65 Gy ≤ 30% and V40 Gy ≤ 60%. Results Among 39 patients, 35 (90%), 19 (49%) and 13 (33%) and 38 (97%), 38 (97%) and 34 (87%) patients before and after the spacer insertion fulfilled rectum dose constraints for low-, intermediate- and high-risk plans, respectively. A hydrogel spacer significantly reduced rectum dose and improved the rectum dose constraints fulfillment rate in intermediate (P < 0.01) and high (P < 0.01), but no difference was found in low-risk plan (P = 0.25). On multivariate analysis, spacer use was associated with the higher rectum dose constraints fulfillment rate. Conclusions A hydrogel spacer reduced rectum dose and improved the dose constraints fulfillment rate in three-dimensional conformal radiotherapy plan. Although IMRT is the standard treatment, 3D-CRT using a hydrogel spacer may be a treatment option.

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Strategies to evaluate the impact of rectal volume on prostate motion during three-dimensional conformal radiotherapy for prostate cancer

Radiologia Brasileira ◽

10.1590/0100-3984.2015.0005 ◽

2016 ◽

Vol 49 (1) ◽

pp. 17-20 ◽

Cited By ~ 1

Author(s):

Ana Paula Diniz Fortuna Poli ◽

Rodrigo Souza Dias ◽

Adelmo José Giordani ◽

Helena Regina Comodo Segreto ◽

Roberto Araujo Segreto

Keyword(s):

Prostate Cancer ◽

Three Dimensional ◽

Conformal Radiotherapy ◽

Prostate Motion ◽

Rectal Volume ◽

Three Dimensional Conformal Radiotherapy ◽

Interfraction Motion ◽

The Impact ◽

Anterior Posterior ◽

3D Crt

Abstract Objective: To evaluate the rectal volume influence on prostate motion during three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. Materials and Methods: Fifty-one patients with prostate cancer underwent a series of three computed tomography scans including an initial planning scan and two subsequent scans during 3D-CRT. The organs of interest were outlined. The prostate contour was compared with the initial CT images considering the anterior, posterior, superior, inferior and lateral edges of the organ. Variations in the anterior limits and volume of the rectum were assessed and correlated with prostate motion in the anteroposterior direction. Results: The maximum range of prostate motion was observed in the superoinferior direction, followed by the anteroposterior direction. A significant correlation was observed between prostate motion and rectal volume variation ( p = 0.037). A baseline rectal volume superior to 70 cm3 had a significant influence on the prostate motion in the anteroposterior direction ( p = 0.045). Conclusion: The present study showed a significant interfraction motion of the prostate during 3D-CRT with greatest variations in the superoinferior and anteroposterior directions, and that a large rectal volume influences the prostate motion with a cutoff value of 70 cm3. Therefore, the treatment of patients with a rectal volume > 70 cm3 should be re-planned with appropriate rectal preparation.

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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

Journal of Clinical Oncology ◽

10.1200/jco.2000.18.9.1936 ◽

2000 ◽

Vol 18 (9) ◽

pp. 1936-1941 ◽

Cited By ~ 46

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.

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