(S011) Hypofractionated vs Standard Fractionated Proton Beam Therapy for Early-Stage Prostate Cancer: Interim Results of a Randomized Prospective Trial

OncologyOncology Vol 29 No 4_Suppl_1
Volume 29
Issue 4_Suppl_1

Patients tolerated proton therapy in this randomized trial well, with excellent QoL scores, persistent low IPSS, and no grade ≥ 3 AEs in either arm. Thus far, there is no apparent clinical difference in outcomes with hypofractionated proton beam therapy compared to standard fractionation.

William F. Hartsell, MD, Megan Dunn, PhD, Gary Larson, MD, Carlos Vargas, MD; CDH Proton Center; Proton Collaborative Group; ProCure Proton Center; Mayo Clinic

PURPOSE: After prostate cancer treatment, most adverse event (AE) and quality of life (QoL) changes can be initially identified within the first 2 years. The purpose of this interim analysis is to determine if there are differences in terms of QoL, International Prostate Symptom Score (IPSS), or AEs among prostate cancer patients treated on a randomized prospective trial with either standard fractionation or hypofractionation.

MATERIALS AND METHODS: Eighty-two patients were randomized to 38 Gy(relative biologic effectiveness [RBE]) in 5 treatments (n = 49) vs 79.2 Gy(RBE) in 44 treatments (n = 33). All patients had stage I prostate cancer and were treated with proton therapy using fiducial markers and daily image guidance.

RESULTS: Median follow-up for both groups was 18 months, with 33 patients reaching follow-up of 2 years or more. Patient characteristics for both groups were similar, with most patients being T1c (84%) and all having a Gleason score of 6 and a prostate-specific antigen (PSA) level < 10 ng/mL (median, 5.6 ng/mL). Baseline median IPSS was 5 for the 5-fraction arm (range: 0–15), and median IPSS was also 5 for the 44-fraction arm (range: 0–14). There was no difference between the two groups with regard to Expanded Prostate Index Composite (EPIC) urinary, bowel, or sexual function scores at 3, 6, 9, 12, 18, 24, or 36 months. The only significant difference was the IPSS score at 12 months: 5 for the 44-fraction arm vs 8 for the 5-fraction arm (P = .03), but there was no difference in the IPSS scores at the other time points. No grade ≥ 3 AEs were seen in either arm.

CONCLUSIONS: Patients tolerated proton therapy in this randomized trial well, with excellent QoL scores, persistent low IPSS, and no grade ≥ 3 AEs in either arm. Thus far, there is no apparent clinical difference in outcomes with hypofractionated proton beam therapy compared to standard fractionation.

Proceedings of the 97th Annual Meeting of the American Radium Society - americanradiumsociety.org

Articles in this issue

(P005) Ultrasensitive PSA Identifies Patients With Organ-Confined Prostate Cancer Requiring Postop Radiotherapy
(P001) Disparities in the Local Management of Breast Cancer in the United States According to Health Insurance Status
(P002) Predictors of CNS Disease in Metastatic Melanoma: Desmoplastic Subtype Associated With Higher Risk
(P003) Identification of Somatic Mutations Using Fine Needle Aspiration: Correlation With Clinical Outcomes in Patients With Locally Advanced Pancreatic Cancer
(P004) A Retrospective Study to Assess Disparities in the Utilization of Intensity-Modulated Radiotherapy (IMRT) and Proton Therapy (PT) in the Treatment of Prostate Cancer (PCa)
(S001) Tumor Control and Toxicity Outcomes for Head and Neck Cancer Patients Re-Treated With Intensity-Modulated Radiation Therapy (IMRT)-A Fifteen-Year Experience
(S003) Weekly IGRT Volumetric Response Analysis as a Predictive Tool for Locoregional Control in Head and Neck Cancer Radiotherapy 
(S004) Combination of Radiotherapy and Cetuximab for Aggressive, High-Risk Cutaneous Squamous Cell Cancer of the Head and Neck: A Propensity Score Analysis
(S005) Radiotherapy for Carcinoma of the Hypopharynx Over Five Decades: Experience at a Single Institution
(S002) Prognostic Value of Intraradiation Treatment FDG-PET Parameters in Locally Advanced Oropharyngeal Cancer
(P006) The Role of Sequential Imaging in Cervical Cancer Management
(P008) Pretreatment FDG Uptake of Nontarget Lung Tissue Correlates With Symptomatic Pneumonitis Following Stereotactic Ablative Radiotherapy (SABR)
(P009) Monte Carlo Dosimetry Evaluation of Lung Stereotactic Body Radiosurgery
(P010) Stereotactic Body Radiotherapy for Treatment of Adrenal Gland Metastasis: Toxicity, Outcomes, and Patterns of Failure
(P011) Stereotactic Radiosurgery and BRAF Inhibitor Therapy for Melanoma Brain Metastases Is Associated With Increased Risk for Radiation Necrosis
Related Videos
The risk of radionuclide exposure to the public reflects one reason urologists need to collaborate with radiation oncologists when administering radiopharmaceuticals to patients with prostate cancer.
Switching out beta emitters for alpha emitters, including radium-223, is one way to improve radiopharmaceutical treatment of prostate cancer, according to an expert from Weill Cornell Medicine.
Data demonstrate the feasibility of automated glomerular filtration rate prediction to decide between partial nephrectomy and radical nephrectomy in kidney cancer, according to an expert from the Cleveland Clinic.
Early phase trials investigating cellular therapies, bispecific antibodies, and antibody-drug conjugates for refractory kidney cancer may uncover strategies to overcome resistance mechanisms.
Increasing cancer antigen presentation as well as working with tumor cells in and delivering novel cells to the microenvironment may help in overcoming mechanisms of immune checkpoint inhibitor resistance in refractory renal cell carcinoma.
Lenvatinib plus pembrolizumab appears to be the best option for patients with refractory metastatic renal cell carcinoma who are progressing on immunotherapy combinations or are lenvatinib naïve.
Ipilimumab monotherapy does not appear effective in driving complete responses in refractory renal cell carcinoma despite yielding some progression-free survival intervals, according to an expert from the University of Texas Southwestern Medical Center.
An expert from the University of Texas Southwestern Medical Center discusses several phase 3 clinical trials supporting the use of various single-agent and combination immunotherapy regimens for advanced kidney cancer.
Shilpa Gupta, MD, shares the current standard of care for muscle-invasive bladder cancer and highlights other options that may be suitable for some patients.
An expert from Stanford Medicine that the goal behind a study characterizing circulating tumor DNA and its predictive value is to eventually replace blood marrow exams with a blood draw for those with multiple myeloma.
Related Content