ESTRO 36 Abstract Book

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S702 ESTRO 36 2017
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regional macroscopic relapse.
Aim of the analysis is to evaluate the role of SRT +/-
concomitant androgen deprivation therapy (ADT) in pts
with clinical/radiological/metabolic loco-regional
relapse.
Material and Methods
From 2007 to September 2015, fifty-five pts with
locoregional macroscopic PCa relapse underwent radical
SRT +/- concomitant/adjuvant ADT. Median age at time of
SRT was 72 years. At time of diagnosis 32pts had pT2 PCa,
6 pT3a and 19 pT3b according to TNM AJCC Stratification.
Only 4 pts had abdominal node involvement (pN+).
Gleason Pattern Score was <7 in 8pts, 7 in 35 and >7 in 11
pts. At time of relapse all pts had an elevated PSA: 19
pts <1.0 ng/mL, 22 between 1.1-5 ng/ml and 15 pts >5
ng/mL. Before being submitted to SRT most pts (44/56)
were staged with 18F-Choline CT-PET while 18 pts had also
pelvic MRI to help with for a better RT planning. At the
end of restaging 48/56 had just local relapse (prostatic
bed), 3 nodal Involvement and 4 pts had both. Due to
clinical stage and PSA value, 23 pts were
previously submitted to first line ADT, while 6 pts
received two or more ADT lines. Finally SRT was delivered
in association to concomitant ADT in 25/56 pts in 13 of
whom it was continued with an adjuvant approach
Results
At a median follow up of 36.2 months all pts but 3/56 (5%)
were alive. All pts were treated with high dose RT (2.0-
2.5 Gy/day,28-37 total fractions) with or without
concomitant ADT. Median RT dose was 70 Gy (range 62-
76Gy). Target volume encompassed prostatic bed and
macroscopic lesion in 42 pts (75%), while in the other 14
pelvic abdominal RT was performed due to high risk of
nodal involvement(in 10 pts with prophylactic intent, in 4
pts using a boost on 18F-Choline CT-PET positive nodes).
Three- and 5-year actuarial OS were 97.6%(ES±2.4%) and
88.5%(ES±6.7%), respectively. Three- and 5-year actuarial
Biochemical Free Survival were 71.4%(ES±6.9) and 56.7%
(ES±9.4) respectively while Metastasis Free Survival 90.5%
(ES±4.0%) and 81.2% (ES±6.5%). Nine pts (16%) experienced
distant recurrences: bone lesions were found in 6 pts,
while extra-pelvic nodes in 5 pts (2/9 pts had both). No
grade 4 acute/late toxicities were found, only 1 pt had G3
late Gastrointestinal side effects
Conclusion
Our results of high dose SRT +/- ADT in pts with loco-
regional macroscopic PCa relapse demonstrate an
excellent profile in terms of oncological outcomes (OS,
DFS, MFS) confirming again the important role of SRT even
in this unfavourable subset of pts.
EP-1322 Performance diagnosis of 11c-choline pet/ct
in prostate cancer
P.M. Samper Ots1, A. Luis Cardo1, M.A. Cabeza
Rodriguez2, C. Vallejo Ocaña3, L.A. Glaria Enriquez4, M.L.
Couselo Paniagua5, J. Olivera Vegas6
1 Hospital Rey Juan Carlos, Servicio de Oncologia
Radioterapica, Mostoles - Madrid, Spain
2 Hospital 12 de Octubre, Servicio de Oncologia
Radioterapica, Madrid, Spain
3 Hospital Ramon y Cajal, Servicio de Oncologia
Radioterapica, Madrid, Spain
4 Hospital La Paz, Servicio de Oncologia Radioterapica,
Madrid, Spain
5 Hospital Gomez Ulla, Servicio de Oncología
Radioterapica, Madrid, Spain
6 Fundación Jimenez Diaz, Servicio de Oncologia
Radioterapica, Madrid, Spain
Purpose or Objective
To test the performance of 11C-choline PET/CT in staging
and change the therapeutic decision in prostate cancer
(PC). Correlation of prognostic factors with the detection
of disseminated disease.
Material and Methods
Retrospective observational multicenter study in which
233 patients diagnosed with PC, median age was 68.21
years included. Inclusion criteria: 56 patients (24%) with
high-risk localized PC, 102 patients (43.8%) with
biochemical failure after surgery and 75 patients (32.2%)
with biochemical failure after radiotherapy, all study
negative extension (CT and bone scintigraphy). We
collected the prognostic factors for PC diagnosis and
surgical specimen: PSA, Gleason score, T stage, N stage,
percentage of positive biopsies, perineural invasion and
margins. And in patients with biochemical failure: the
PSA, PSA doubling time (PSADT) and PSA velocity (PSAV)
at the time of failure. The study was approved by the
Ethics Committee for Clinical Research (CEIC) and meets
the standards of data protection. For statistical analysis
SPSS version 22.0 was used.
Results
The 11C-choline PETCT confirmed the diagnosis of the
extension study only in 81 patients (34.7%), changed the
therapeutic indication in 137 patients (58.8%) and
confirmed metastatic disease in 127 patients (54.5%).
Prognostic factors of diagnosis of metastasis in 11C-
choline PETCT in the univariate analysis were: Primary
Gleason ³ 4 (p = 0.002), secondary Gleason ³ 4 (p = 0.039),
Gleason score ³ 8 (p = 0.001), perineural invasion in biopsy
(p = 0.04), perineural invasion in the surgical specimen (p
= 0.029), previous hormone therapy (p = 0.001), the PSA
failure (p = 0.023), the PSADT (p = 0.023), and VPSA (p
<0.001); in the multivariate analysis: primary Gleason
diagnosis (p = 0.001, Gleason score at diagnosis (p =
0.002), PSA in failure (p = 0.005), PSA DT (p = 0.010) and
VPSA (p = 0.000).
Conclusion
11C-choline PET-CT has proven to be cost-effective for the
detection of metastatic disease in high risk patients with
primary Gleason ≥ 4 and Gleason score ≥ 8 diagnostic, and
in patients with biochemical failure and kinetics elevated
PSA, which involve a change in the therapeutic indication.
EP-1323 Role of 68Ga-PSMA PET/CT in radiotherapy
for prostate cancer: A single centre experience
N.S. Hegemann 1, W.P. Fendler2, A. Buchner3, C. Stief3,
M. Niyazi1, P. Bartenstein2, C. Belka1, U. Ganswindt1
1Klinik und poliklinik für Strahlentherapie und
Radioonkologie, Radiation Oncology Ludwig-Maximilians-
University, München, Germany
2Nuclear Medicine, Ludwig-Maximilians-University,
Munich, Germany
3Urology, Ludwig-Maximilians-University, Munich,
Germany
Purpose or Objective
The aim of this study was to determine the potential role
of 68Ga-PSMA PET/CT in radiotherapy (RT) for prostate
cancer.
Material and Methods
A retrospective analysis of 129 patients (pts) with
available 68Ga-PSMA PET/CT (Feb. 2014 - Aug. 2016) was
performed. Potentially influencing factors (androgen
deprivation therapy at time of PET/CT, injected amount
of 68Ga-PSMA-HBED-CC, PSA doubling time ≤/> 10 months,
PSA before PET/CT, T-/N-category and Gleason score)
were evaluated by uni- and multivariate binary logistic
regression analysis. The detection rate of 68Ga-PSMA
PET/CT compared to contrast enhanced CT and its impact
on RT management was analysed.
Results
129 pts (20 at initial diagnosis, 49 with PSA relapse and 60
with PSA persistence after radical prostatectomy)
received 68Ga-PSMA PET/CT prior to RT. The majority of
pts (71.3%) had 68 Ga-PSMA PET/CT positive findings (55.1%
of pts with PSA recurrence, 75% of pts with PSA
persistence and 100% of newly diagnosed pts). The uni-
and multivariate analysis found no significant association
between PET-positive results and above mentioned factors