Vienna, Austria

ESTRO 2023

Session Item

Poster (Digital)
Stereotactic body radiotherapy in bone oligometastatic prostate cancer: a retrospective study
Silvia Scoccianti, Italy


Stereotactic body radiotherapy in bone oligometastatic prostate cancer: a retrospective study

Fabio Trippa1, Sara Costantini1, Sara Terenzi1, Gianluca Ingrosso2, Silvia Scoccianti3, Alessandro Di Marzo1, Beatrice Detti4, Luca Triggiani5, Simona Borghesi6, Lilia Bardoscia7, Paola Puccini8

1Radiation Oncology Centre, Oncology, Terni, Italy; 2Radiation Oncology Centre, Oncology, Perugia, Italy; 3Radiation Oncology Centre, Oncology, Firenze OSMA, Italy; 4Radiation Oncology Centre, Oncology, Firenze Careggi, Italy; 5Radiation Oncology Centre, Oncology, Brescia, Italy; 6Radiation Oncology Centre, Oncology, Arezzo, Italy; 7Radiation Oncology Centre, Oncology, Lucca, Italy; 8Radiaton Oncology, Oncology, Pisa, Italy

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Purpose or Objective

In oligometastatic disease, stereotactic body radiotherapy (SBRT) as metastasis direct treatment (MDT) represents a promising therapeutic option. The aim of our study is to assess the role of SBRT in hormone-sensitive prostate cancer (HSPC) patients (pts) with bone oligometastasis (BM).

Material and Methods

This is a multicentre retrospective study of 75 HSPC pts with 94 BM treated with SBRT between October 2010 and April 2022. Primary endpoints were biochemical disease free survival (bDFS) and time to androgen deprivation therapy (ADT). Secondary endpoints were local control (LC) and toxicity. Median age was 71 yrs (range, 56-87). At the primary diagnosis, median Gleason score was 7 (range, 6-9), median PSA value 9.4 ng/ml (range, 3.1-140.9), and median stage of disease T2c and all pts were N0 and M0. Time from primary treatment to SBRT was 38 m (range, 2–131). Diagnosis of disease relapse was made with Choline-PET/CT in 70 (93%) pts and with PSMA-PET/CT and Conventional Imaging in 1 (1%) and 4 (4%) pts, respectively. Median PSA value before SBRT was 2.2 ng/ml (range 0.01–46). Twenty-five (33%) received concomitant ADT. Sixteen (21%) pts underwent SBRT for >1 synchronous lesion. BM sites were: pelvis in 51 (54%) pts, spine in 32 (34%) pts, and 11 (12%) pts in other sites. The most used fractionation regimens were: 1x24Gy (BED 81.6Gy10), 3x10Gy (BED 50 Gy10) and 5x8Gy (60Gy10). Response was assessed with PSA evaluation scheduled every 3 m during the first yr and then every 6 m. Pts with a reduction or a stability of PSA level were considered responders. Instrumental control was done in case of a PSA level increase.


With a median follow-up of 24 m (range, 1-115), median bDFS from the end of SBRT was 9 m (range, 2-70). Sixty (80%) pts had a decrease of PSA level after SBRT. Of responders, 26 (42%) pts remained biochemical relapse free, the other 34 (58%) pts had a PSA increase due to in-field (7 pts) or out-field progression (27 pts). In the latter case, 8 pts underwent SBRT on a new BM and 13 pts had a systemic progression of disease and were submitted to ADT. Median time to initiation of ADT was 9 m (range, 2-70). No SBRT related acute or late > G2 toxicities were registered.


Our experience shows that SBRT in HSPC with BM can achieve high rates of LC with an excellent risk-benefit profile. Moreover, SBRT confirms to delay ADT allowing to an improvement of quality of life in these subset of pts.