Online

ESTRO 2020

Session Item

Sunday
November 29
11:40 - 12:40
Interdisciplinary Stream 1
Clinical trials
Esther Troost, Germany;
Yolande Lievens, Belgium
2260
Plenary Session
Interdisciplinary
11:50 - 12:00
Surveillance or metastasis-directed Therapy for OligoMetastatic Prostate cancer (STOMP)
Piet Ost, Belgium
OC-0370

Abstract

Surveillance or metastasis-directed Therapy for OligoMetastatic Prostate cancer (STOMP)
Authors: Filip Ameye.(AZ Maria-Middelares Ghent, Urology, Gent, Belgium), Ignace Billiet.(AZ Groeninge Kortrijk, Urology, Gent, Belgium), Renée Bultijnck.(Ghent University Hospital, Radiotherapy, Gent, Belgium), Aurélie De Bruycker.(Ghent University Hospital, Radiotherapy, Gent, Belgium), Kathia De Man.(Ghent University Hospital, Department of Nuclear Medicine, Gent, Belgium), Karel Decaestecker.(Ghent University Hospital, Urology, Gent, Belgium), Louke Delrue.(Ghent University Hospital, Department of Radiology, Gent, Belgium), Valérie Fonteyne.(Ghent University Hospital, Radiotherapy, Gent, Belgium), Els Goetghebeur.(Ghent University, Department of Applied Mathematics- Computer Science and Statistics, Gent, Belgium), Steven Joniau.(Catholic University Leuven, Urology, Gent, Belgium), Bieke Lambert.(AZ Maria-Middelares, Department of Nuclear Medicine, Gent, Belgium), Nicolaas Lumen.(Ghent University Hospital, Urology, Gent, Belgium), Piet Ost.(University Hospital Ghent, Radiotherapy, Gent, Belgium), Dries Reynders.(Ghent University, Department of Applied Mathematics- Computer Science and Statistics, Gent, Belgium), Friedl Vanhaverbeke.(AZ Nikolaas, Urology, Gent, Belgium), Geert Villeirs.(Ghent University Hospital, Department of Radiology, Gent, Belgium)
Show Affiliations
Purpose or Objective

Multiple randomized phase II trials suggest that metastasis-directed therapy (MDT) for oligometastatic prostate cancer (PCa) improves progression-free survival, but the majority of trials lack longer follow-up. We present the updated 5-year results from the STOMP-trial.

Material and Methods

In this multicentre, randomised, phase II study, asymptomatic PCa patients were eligible in case of a biochemical recurrence following primary PCa treatment with curative intent and presenting with up to 3 extracranial on choline PET-CT and a serum testosterone levels > 50 ng/ml. Patients were randomly assigned (1:1) to either surveillance or MDT of all detected lesions. Randomisation was balanced dynamically on two factors: PSA doubling time (≤3 vs. > 3 months) and nodal vs non-nodal metastases. The primary endpoint was androgen deprivation therapy (ADT)-free survival. Castrate resistant prostate cancer-free survival (CRPC) was a secondary endpoint. Tests were performed two-sided; p values less than 0.20 were deemed significant.

Results

The 5-year ADT-free survival was 8% for the surveillance group and 34% for the MDT group (Figure 1, hazard ratio 0.57 [80% CI: 0.38-0.84], log-rank p = 0.06). There was no significant difference in effect for the different stratification factors (interaction test). The 5-year CRPC-free survival was 53% for the surveillance group and 76% for the MDT group (hazard ratio 0.62 [80% CI: 0.35−1.09]; log−rank p = 0.27). At a median follow for survival of 5.3 years (IQR 4.3-6.3), the 5-year overall survival was 85%, with 6 out of 14 deaths attributed to prostate cancer.

Conclusion

The updated STOMP trial outcomes confirm the earlier reported significant difference in ADT free survival in favor of the MDT group compared to surveillance. Prostate-cancer related mortality is low within the first 5 years of diagnosis of oligorecurrent prostate cancer.