PV QA 1 - Poster Viewing Q&A 1
SU_25_2250 - External Beam Re-Irradiation of Locally Recurrent Prostate Cancer With FFF-VMAT
Sunday, October 21
1:15 PM - 2:45 PM
Location: Innovation Hub, Exhibit Hall 3
External Beam Re-Irradiation of Locally Recurrent Prostate Cancer With FFF-VMAT
G. R. D'Agostino1, L. Di Brina1, C. Franzese1, S. Tomatis1, C. Iftode1, D. Franceschini1, E. Clerici1, G. Reggiori1, A. Tozzi1, P. Navarria1, and M. Scorsetti1,2; 1Humanitas Clinical and Research Hospital, Rozzano - Milan, Italy, 2Humanitas University, Rozzano - Milan, Italy
Purpose/Objective(s): The introduction of IMRT, IGRT, and VMAT techniques, has substantially contributed to the delivery of more safe and effective radiation treatments to patients affected by prostate cancer, even if previously irradiated. In this study we report our experience on re-irradiation in a sample of 22 patients previously irradiated for prostate cancer and affected by local relapse of disease.
Materials/Methods: Patients affected by recurrent prostate cancer previously irradiated were included in this study, provided that they had an increased PSA, diagnostic for biochemical relapse, a PET-Choline revealing the presence of a local recurrence of disease, and were unwilling to start an androgen deprivation therapy. Re-irradiation consisted of a stereotactic treatment delivered by FFF IGRT-VMAT technology in 5 daily fractions. Clinical response was evaluated with PSA and physical examination. Toxicity assessment according to CTCAE (v. 4.01) criteria. During follow-up, PET-Choline was performed in the cases of PSA rising.
Results: Between November, 2012 and November, 2017, 22 patients (median age 77 years, range 59-85) were submitted to re-irradiation on prostate (n=12, 54.5%), prostatic bed (n=8, 36.4%) or prostate and local recurrence (n=2 seminal vesicle, ischium 9.1%). Previous treatment consisted on a median total dose of 74 Gy on prostate or prostatic bed (range 66-76). Median time from previous radiotherapy was 87 months (range 26-137). Median PSA at the moment of recurrence was 2.9 ng/ml (mean 3.8, range 1.0-13.5). Re-irradiation delivered a median total dose of 25 Gy (range 25-30) in a median number of 5 fractions (range 5-6). An immediate biochemical response was observed in all cases. Median PSA nadir after treatment was 0.66 ng/ml (mean 1.41, range 0.11-6.0, p=0.0004). Median difference between initial and nadir PSA was 2.1 ng/ml (range 0.2-11.0). Median time to nadir was 5.4 months (range 2.2-20). Acute toxicity was mainly genito-urinary, represented by pollakiuria and dysuria grade 1 (n=10, 45.5%) or grade 2 (n=3, 13.6%). One patient (4.5%) had a grade 3 hematuria. A grade 1 GU late toxicity was observed in 3 patients (17.7%), G3 in 1 patient (4.5%, urethral obstruction). GI toxicity was negligeable. At a median follow-up of 28 months (range 5-57) all patients are still alive, a biochemical recurrence was experienced by 13 patients (59.1%), confirmed by a positive PET-choline in 12 cases (7 local recurrences, 1 distant metastasis, 4 local and distant progression). Median BFS was 19 months, 1- and 2-year BFS was 84.7% and 39.4%, respectively. Median LC was 30 months, 1- and 2-year LC was 94.4% and 58.1%, respectively.
Conclusion: Re-irradiation of patients affected by prostate cancer, and previously treated with radiation therapy, is a valuable option, which can be safely considered in order to delay the beginning of an hormonal treatment.
Author Disclosure: G.R. D'Agostino: None. L. Di Brina: None. S. Tomatis: None. C. Iftode: None. A. Tozzi: None. M. Scorsetti: None.