ESTRO 36 Abstract Book

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S725 ESTRO 36
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Grassi 2, M. Lo Russo2 , I. Meattini2, S. Scoccianti2, M.
Mangoni2, L. Livi2
1 Azienda Ospedaliera Universitaria Careggi,
Radiotherapy Unit, Firenze, Italy
2 University of Florence, Radiotherapy Department,
Florence, Italy
3 IFCA, Radiotherapy Department, Florence, Italy
Purpose or Objective
Advances in metabolic imaging allows the detection of
oligorecurrent nodal disease in prostate cancer patients
after primary surgical or radiation treatment (RT): focal
nodal stereotactic RT could be proposed in order to treat
the site of recurrence. The aim of the study is to evaluate
efficacy and toxicity of single fraction robotic stereotactic
radiation therapy (rSBRT) for isolated nodal failure in
prostate cancer patients
Material and Methods
Twenty-three prostate cancer patients with 27 isolated
nodal recurrence were treated by single fraction rSBRT
between April 2012 and March 2016. Lymphnodal disease
was assessed by 18F-choline positron emission tomography–
computed tomography ( 18F-chol-PET); all patients
received single fraction rSBRT. PSA was assessed at 3
months and every 3 months following treatment. Toxicity
was assessed by the Common Terminology Criteria for
Adverse Events toxicity scale (CTCAE v.4.03).
Results
Median patient age at rSBRT was 75 (54-85) years. All
patients underwent definitive RT (2, 8.7%) or surgery (21,
91.3%) as primary treatment to the prostate; among
operated patients, RT was administered as an adjuvant or
salvage treatment in 3 (13.0%) and 3 (13.0%) patients
respectively. Median time from primary treatment to
relapse was 69.5 (7.6-205.4) months; median pre-
treatment PSA value was 2.13 ng/ml (0,35-19.9). Five
patients (21.7%) were receiving endocrine therapy (ET) for
at least 6 months following prior biochemical failure (BF).
Nodal sites of disease were pelvic and lumboaortic nodes
in 22 (81.4%) and 5 (18.6%) cases, respectively;four
patients were simultaneously treated on a synchronous
nodal relapse. Median dose was 24 (20-24) Gy. At 3
months, 12 (52.2%) patients showed biochemical response
(median decline -64.6%, 0.8-97.8); 11 (47.8%) patients
experienced early PSA progression (median elevation
+30.8%, 2.9-390.9). At the time of our analysis, after a
median follow-up of 13.6 months (6.0-47.8), 8 patients
showed no evidence of disease, 2 patients were continuing
ET with stable PSA levels, while 13 patients experienced
biochemical progression: among them, 7 patients started
ET for 18F-chol-PET-negative disease, 2 patients had nodal
relapse on non-irradiated site and 4 patients developed
distant metastasis. At statistical analysis, median time to
BF was 10.0 months. Overall Biochemical Relapse-Free
Survival (bPFS) was 56.5% at 6 months and 47.8% at 12
months; no predictive factor was related to bPFS. Subset
analysis in responding patients showed a median time to
BF of 14.7 months; PSA level >4.0 ng/ml showed a
borderline predictive value for BF (p=0.054). Grade1
bladder toxicity was reported in one case.
Conclusion
Isolated nodal relapse of prostate cancer can be safely
treated by single fraction rSBRT with excellent tolerance
and promising biochemical control; careful selection of
patients is mandatory to avoid unnecessary treatment of
patient with undetectable advanced disease.
EP-1353 Salvage hypofractionated radiotherapy for
prostate cancer: acute toxicity
S. Saldi1, R. Bellavita2, I. Palumbo3, C. Mariucci1, E.
Arena1, M. Lupattelli2 , A. Podlesko1, S. Russo2, R.
Dottorini2, V. Bini4, C. Aristei3
1 University of Perugia, Radiation Oncology Section,
Perugia, Italy
2Perugia General Hospital, Radiation Oncology Section,
Perugia, Italy
3University of Perugia and Perugia General Hospital,
Radiation Oncology Section, Perugia, Italy
4Perugia General Hospital, Internal Medicine Endocrin
and Metabolic Sciences Section, Perugia, Italy
Purpose or Objective
To evaluate acute toxicity and the preliminary outcome of
hypofractionated salvage radiotherapy (Hypo-SRT) with
helical tomotherapy after radical prostatectomy (RP).
Material and Methods
From March 2013 to July 2016, 58 patients underwent
Hypo-SRT for biochemical (BR) or local recurrence (LR)
after radical prostatectomy (PR). Median age was 67 years
(range 52-84). The surgical Gleason score was : <7 in 24
patients (41%), 7 in 22 (38%), >7 in 12 (21%); median PSA
pre-SRT was 0.258 ng/ml (range: 0.2-8.65). RT
schedule: 24/58 (41%) patients with BR received 2.25 Gy
in 32 fractions (Total dose:72 Gy); 34/58 (59%) patients
with LR received 2.1 Gy in 33 fractions (Total dose: 69.3
Gy) to the prostate/seminal vesicle bed and 2.25 Gy in 33
fractions to the LR site (total dose:74.25 Gy) using a
simultaneous integrated boost (SIB) technique; 6/58 (10%)
patients received 1.6 Gy to the pelvic lymph nodes (total
dose 52.8 Gy), using a SIB technique. Hormone therapy (
HT-LHRH analogue and/or anti-androgen) was
administered to 17 patients (29%) with high risk features.
Toxicity was graded according to the Common
Terminology Criteria for Adverse Events version v4.0.
Biochemical failure was defined by ASTRO criteria. The
Kaplan-Meier method determined time-to-acute toxicity
events and the Mann-Whitney test compared clinical and
dosimetric variables in groups with and without acute
toxicity.
Results
The median follow-up was 12 months (range:3-41).The
median duration of HT was 85 months (range 2-168). Only
G1-G2 acute genitourinary (GU) and intestinal (GI)
toxicities occurred. Acute grade 1 GU toxicity occurred in
28 patients (48%), with 25 (43%) developing cystitis and
3 (5%) hematuria. Acute grade 2 GU toxicity (cystitis)
developed in 6/58 (10%) patients, with 1 also affected by
urinary retension (2%). Acute grade 1 GI toxicity (proctitis)
occurred in 25/58 patients (43%), which was associated
with rectal bleeding in 2 (3%). Acute grade 2 GI toxicity
(proctitis) developed in 4/58 (7%) patients, which was
associated with rectal bleeding in 1 (2%). Post Hypo-ART
the median PSA was 0.1 ng/ml (range:0-7.01) and the
nadir was 0.03 ng/ml (range: 0-5.67). Biochemical
recurrence and /or loco-regional relapse occurred in
10/58 (17%) patients at a median of 19 months after
treatment (range: 10-40). Statistical analysis: after Hypo-
ART there was 50% probability of developing acute GU
toxicity on day 52 and GI toxicity on day 43. Dmax to the
prostate/seminal vesicle bed was greater in patients who
developed acute GI toxicity.
Conclusion
Low grade acute GU and GI toxicity and early biochemical
response demonstrated that moderate Hypo-SRT was safe
and effective. A longer follow-up is required to confirm
these outcomes.
EP-1354 Delayed Salvage Radiotherapy for Macroscopic
Local Recurrence after Radical Prostatectomy
M. Shelan1, S. Odermatt1, B. Bojaxhiu1, O. Elicin1, D.M.
Aebersold1, A. Dal Pra1
1Bern University Hospital, Radiation Oncology, Bern,
Switzerland