OC-0509 10-year outcome of ultrahypofractionated stereotactic RT from two multicenter prostate cancer trials
R. Meier1, I. Kaplan2, D. Bloch3, R. Chen4, B. Kane5, G. Henning6, S. Woodhouse7, T. Royce8, C. Cotrutz9, D. Fuller10
1Swedish Cancer Institute, Radiation Oncology, Seattle, USA; 2Beth Israel Deaconess Medical Center, Radiation Oncology, Boston, USA; 3Stanford University, Biomedical Data Science, Stanford, USA; 4University of Kansas, Radiation Oncology, Lawrence, USA; 5Community Medical, Radiation Oncology, Fresno, USA; 6St. Joseph Mercy, Radiation Oncology, Ann Arbor, USA; 7Carle Cancer Institute, Radiation Oncology, Normal, USA; 8UNC Health, Radiation Oncology, Chapel Hill, USA; 9Swedish Cancer Institute, Swedish Radiosurgery Center, Seattle, USA; 10Genesis Healthcare Partners, Radiation Oncology, San Diego, USA
Purpose or Objective
We previously published 5-year outcomes in two large multicenter trials of ultrahypofractionated stereotactic radiotherapy for organ-confined prostate cancer. Randomized trials have subsequently demonstrated that, with similar follow up, ultrahypofractionated radiotherapy is a suitable alternative to conventional fractionation. Since data beyond five years are lacking, we now present combined 10-year survival and late toxicity outcomes from these two prospective trials.
39 centers enrolled 569 patients with prostate adenocarcinoma: 284 with low-risk and 285 with intermediate- risk disease. 101 patients had unfavorable intermediate-risk tumors (Gleason 4+3, two unfavorable risk factors, and/or ≥50% biopsy cores positive). All were treated with a non-coplanar robotic stereotactic platform using real-time tracking of implanted fiducials. Two dose regimens were used: 40Gy in 5 fractions of 8Gy, and 38Gy in 4 fractions of 9.5Gy. Adjuvant androgen deprivation therapy (ADT) was not allowed. Early (within 3 months of treatment) toxicity and 5-year survival outcomes have been previously described; we report outcomes in patients consenting to study participation beyond 5 years. Toxicities were assessed using Common Terminology Criteria for Adverse Events (CTCAE) version 3. All reported rates are actuarial, using Kaplan-Meier method. For relapse free survival (RFS), failure included initiating salvage or systemic therapy, local/regional/distant failure, or biochemical relapse using the “nadir + 2” definition.
Results
Median follow up was 8.1 years, with 109 patients followed for 10 years. There were no grade 4-5 toxicities. Actuarial 10-year grade 2 and grade 3 late GU toxicity rates were 14.9% and 2.2%, respectively. The 10-year late grade 2 GI toxicity rate was 3.6%; there were no grade 3 GI toxicities. For the entire group, 10-year overall survival rate was 88.1%, local failure rate was 2.5%, and RFS rate was 92.0%. 10-year RFS for low- and intermediate-risk groups were 98.5% and 85.8%, respectively. 10-year RFS for favorable and unfavorable intermediate-risk patients were 91.5% and 75.3%. No statistically significant differences in rates of toxicity, survival, local failure, nor RFS were observed between the two dose regimens.
Conclusion
10 years following treatment of organ-confined prostate cancer with ultrahypofractionated robotic stereotactic radiotherapy, toxicity rates continue to be minimal, with few additional events observed beyond 5 years. Overall survival, local control, and RFS rates remain favorable at 10 years, confirming stereotactic radiotherapy as a suitable option for low- and intermediate-risk prostate cancer.
OC-0509 10-year outcome of ultrahypofractionated stereotactic RT from two multicenter prostate cancer trials
R. Meier1, I. Kaplan2, D. Bloch3, R. Chen4, B. Kane5, G. Henning6, S. Woodhouse7, T. Royce8, C. Cotrutz9, D. Fuller10
1Swedish Cancer Institute, Radiation Oncology, Seattle, USA; 2Beth Israel Deaconess Medical Center, Radiation Oncology, Boston, USA; 3Stanford University, Biomedical Data Science, Stanford, USA; 4University of Kansas, Radiation Oncology, Lawrence, USA; 5Community Medical, Radiation Oncology, Fresno, USA; 6St. Joseph Mercy, Radiation Oncology, Ann Arbor, USA; 7Carle Cancer Institute, Radiation Oncology, Normal, USA; 8UNC Health, Radiation Oncology, Chapel Hill, USA; 9Swedish Cancer Institute, Swedish Radiosurgery Center, Seattle, USA; 10Genesis Healthcare Partners, Radiation Oncology, San Diego, USA
Purpose or Objective
We previously published 5-year outcomes in two large multicenter trials of ultrahypofractionated stereotactic radiotherapy for organ-confined prostate cancer. Randomized trials have subsequently demonstrated that, with similar follow up, ultrahypofractionated radiotherapy is a suitable alternative to conventional fractionation. Since data beyond five years are lacking, we now present combined 10-year survival and late toxicity outcomes from these two prospective trials.
Materials and Methods
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S392
ESTRO 2021
39 centers enrolled 569 patients with prostate adenocarcinoma: 284 with low-risk and 285 with intermediate- risk disease. 101 patients had unfavorable intermediate-risk tumors (Gleason 4+3, two unfavorable risk factors, and/or ≥50% biopsy cores positive). All were treated with a non-coplanar robotic stereotactic platform using real-time tracking of implanted fiducials. Two dose regimens were used: 40Gy in 5 fractions of 8Gy, and 38Gy in 4 fractions of 9.5Gy. Adjuvant androgen deprivation therapy (ADT) was not allowed. Early (within 3 months of treatment) toxicity and 5-year survival outcomes have been previously described; we report outcomes in patients consenting to study participation beyond 5 years. Toxicities were assessed using Common Terminology Criteria for Adverse Events (CTCAE) version 3. All reported rates are actuarial, using Kaplan-Meier method. For relapse free survival (RFS), failure included initiating salvage or systemic therapy, local/regional/distant failure, or biochemical relapse using the “nadir + 2” definition.
Results
Median follow up was 8.1 years, with 109 patients followed for 10 years. There were no grade 4-5 toxicities. Actuarial 10-year grade 2 and grade 3 late GU toxicity rates were 14.9% and 2.2%, respectively. The 10-year late grade 2 GI toxicity rate was 3.6%; there were no grade 3 GI toxicities. For the entire group, 10-year overall survival rate was 88.1%, local failure rate was 2.5%, and RFS rate was 92.0%. 10-year RFS for low- and intermediate-risk groups were 98.5% and 85.8%, respectively. 10-year RFS for favorable and unfavorable intermediate-risk patients were 91.5% and 75.3%. No statistically significant differences in rates of toxicity, survival, local failure, nor RFS were observed between the two dose regimens.
Conclusion
10 years following treatment of organ-confined prostate cancer with ultrahypofractionated robotic stereotactic radiotherapy, toxicity rates continue to be minimal, with few additional events observed beyond 5 years. Overall survival, local control, and RFS rates remain favorable at 10 years, confirming stereotactic radiotherapy as a suitable option for low- and intermediate-risk prostate cancer.
Check out figures 17-20 Table 18c-d Table 23 Fig 22 etc and most importantly Fig 21c
Cyberknife does Better than conventional linacs
Supplements The Lancet Oncology article 2022