ESTRO 2021 Abstract Book

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ESTRO 2021

univariate

multivariate

median P FS

Patient chracteristics

n

p-value

HR (95% CI)

p-value

ISUP Score

0.271

0.95 (0.43-2.09)

0.898

≤3

39

NR

≥4

61

NR

Initial tumor stage

0.695

1.16 (0.35-3.8)

0.813

≤ T2

21

NR

≥ T3

79

NR

Initial nodal stage

0.625

0.73 (0.34-1.56)

0.418

N0

54

NR

N1

42

NR

Number of metastases

0.319

1.40 (0.90-2.18)

0.132

1

35

NR

2

23

NR

≥3

42

NR

Lmyph node localisation

0.075

2.14 (0.84-5.43)

0.110

pelvic

83

NR

paraaortic (+/-pelvic)

17

23.6

Concomittant ADT

0.001

0.231 (0.09-0.61)

0.003

present

83

NR

absent

17

18.8

PSA persistence vs. PSA recurrence

0.143

2.00 (0.55-7.33)

0.293

PSA persistence

76

NR

PSA recurrence

22

NR

PSA before sRT

0.013

2.25 (1.02-4.93)

0.044

< 1 ng/ml

42

NR

≥ 1 ng/ml 26.3 Uni- and multivariate analysis for factors associated with progression-free survival . Abbreviations: ADT = androgen deprivation therapy; CI = confidence interval; HR = hazard ratio; ISUP: International Society of Urological Pathology; NR = not reached; PSA = prostate specific antigen; sRT = salvage radiotherapy 58

Conclusion PSMA PET/CT-guided sRT is an effective local treatment option. Concomitant ADT and a PSA value < 1 ng/ml before sRT were predictive for PFS.

PD-0913 Local treatment to the primary tumor and PSA changes as prognostic factors in mCRPC F. Lopez Campos 1 , D. Lorente 2 , C. Llacer-Pérez 3 , I. Henríquez 4 , P. Peleteiro 5 , A. Gómez-Iturriaga 6 , M. Ramírez- Backhaus 7 , S. Álvarez 8 , T. Alonso-Gordoa 9 , J. Molina-Cerrillo 9 , C. Vallejo 1 , A. Hervás 1 , J. Navarro-Castellón 10 , J. Gómez 4 , V. Morillo 11 , R. Lozano 12 , N. Romero-Laorden 13 , R. García 14 , A. Hernández-Corrales 1 , L. Pelari 1 , C. Ferrer-Albiach 15 , S. Sancho 1 , E. Castro 16 , D. Olmos 12 1 Hospital Universitario Ramón y Cajal, Radiation Oncology, Madrid, Spain; 2 Hospital Provincial de Castellón, Medical Oncology, Castellón, Spain; 3 Hospital Virgen de la Victoria y Regional de Málaga, Medical Oncology, Málaga, Spain; 4 Hospital Universitario Sant Joan de Reus, Radiation Oncology, Reus, Spain; 5 Hospital Clínico Universitario de Santiago de Compostela, Radiation Oncology, Santiago de Compostela, Spain; 6 Hospital Universitario de Cruces, Radiation Oncology, Baracaldo, Spain; 7 Instituto Valenciano de Oncología, Urology, Valencia, Spain; 8 Hospital Universitario Ramón y Cajal, Urology, Madrid, Spain; 9 Hospital Universitario Ramón y Cajal, Medical Oncology, Madrid, Spain; 10 Hospital Central de la Defensa Gómez Ulla, Radiation Oncology, Madrid, Spain; 11 Hospital Provincial de Castellón, Radiation oncology, Castellón, Spain; 12 Centro Nacional de Investigaciones Oncológicas, Prostate Cancer Unit, Madrid, Spain; 13 Hospital Universitario La Princesa, Medical Oncology, Madrid, Spain; 14 Hospital Clínico Universitario de Valencia, Radiation Oncology, Madrid, Spain; 15 Hospital Provincial de Castellón, Radiation Oncology, Castellón, Spain; 16 Instituto de Investigación Biomédica de Málaga, Medical Oncology, Málaga, Spain Purpose or Objective In metastatic castration-resistant prostate cancer (mCRPC) patients, retrospective analyses have noted an association between previous local treatment to the primary tumour and improved overall survival (OS). Variations in PSA levels in mCRPC are widely used in the monitoring of response to treatment with Abiraterone or Enzalutamide (Abi/Enza), although it has not been validated as an early biomarker for OS. We aimed to evaluate the significance of the previous local treatment to the primary tumor and early PSA changes in