Development of PSMA-PET-guided CT-based radiomic signature to predict biochemical recurrence after salvage radiotherapy.

Spohn, Simon K B; Schmidt-Hegemann, Nina-Sophie; Ruf, Juri; Mix, Michael; Benndorf, Matthias; Bamberg, Fabian; Makowski, Marcus R; Kirste, Simon; Rühle, Alexander; Nouvel, Jerome; Sprave, Tanja; Vogel, Marco M E; Galitsnaya, Polina; Gschwend, Jürgen E; Gratzke, Christian; Stief, Christian; Löck, Steffen; Zwanenburg, Alex; Trapp, Christian; Bernhardt, Denise; Nekolla, Stephan G; Li, Minglun; Belka, Claus; Combs, Stephanie E; Eiber, Matthias; Unterrainer, Lena; Unterrainer, Marcus; Bartenstein, Peter; Grosu, Anca-L; Zamboglou, Constantinos; Peeken, Jan C     «

Spohn, Simon K B; Schmidt-Hegemann, Nina-Sophie; Ruf, Juri; Mix, Michael; Benndorf, Matthias; Bamberg, Fabian; Makowski, Marcus R; Kirste, Simon; Rühle, Alexander; Nouvel, Jerome; Sprave, Tanja; Vogel, Marco M E; Galitsnaya, Polina; Gschwend, Jürgen E; Gratzke, Christian; Stief, Christian; Löck, Steffen; Zwanenburg, Alex; Trapp, Christian; Bernhardt, Denise; Nekolla, Stephan G; Li, Minglun; Belka, Claus; Combs, Stephanie E; Eiber, Matthias; Unterrainer, Lena; Unterrainer, Marcus; Bartenstein, Pe...     »

PURPOSE: To develop a CT-based radiomic signature to predict biochemical recurrence (BCR) in prostate cancer patients after sRT guided by positron-emission tomography targeting prostate-specific membrane antigen (PSMA-PET). MATERIAL AND METHODS: Consecutive patients, who underwent 68Ga-PSMA11-PET/CT-guided sRT from three high-volume centers in Germany, were included in this retrospective multicenter study. Patients had PET-positive local recurrences and were treated with intensity-modulated sRT. Radiomic features were extracted from volumes of interests on CT guided by focal PSMA-PET uptakes. After preprocessing, clinical, radiomics, and combined clinical-radiomic models were developed combining different feature reduction techniques and Cox proportional hazard models within a nested cross validation approach. RESULTS: Among 99 patients, median interval until BCR was the radiomic models outperformed clinical models and combined clinical-radiomic models for prediction of BCR with a C-index of 0.71 compared to 0.53 and 0.63 in the test sets, respectively. In contrast to the other models, the radiomic model achieved significantly improved patient stratification in Kaplan-Meier analysis. The radiomic and clinical-radiomic model achieved a significantly better time-dependent net reclassification improvement index (0.392 and 0.762, respectively) compared to the clinical model. Decision curve analysis demonstrated a clinical net benefit for both models. Mean intensity was the most predictive radiomic feature. CONCLUSION: This is the first study to develop a PSMA-PET-guided CT-based radiomic model to predict BCR after sRT. The radiomic models outperformed clinical models and might contribute to guide personalized treatment decisions.      «

PURPOSE: To develop a CT-based radiomic signature to predict biochemical recurrence (BCR) in prostate cancer patients after sRT guided by positron-emission tomography targeting prostate-specific membrane antigen (PSMA-PET). MATERIAL AND METHODS: Consecutive patients, who underwent 68Ga-PSMA11-PET/CT-guided sRT from three high-volume centers in Germany, were included in this retrospective multicenter study. Patients had PET-positive local recurrences and were treated with intensity-modulated sRT....     »