Response on DCE-MRI predicts outcome of salvage radiotherapy for local recurrence after radical prostatectomy

• Published in: Tumori 2021-02, Vol.107 (1), p.55-63
• Main Authors: Sanguineti, Giuseppe, Bertini, Luca, Faiella, Adriana, Ferriero, Maria Consiglia, Marzi, Simona, Farneti, Alessia, Landoni, Valeria
• Format: Article
• Language: English
• Subjects: Aged; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neoplasm Recurrence, Local - diagnostic imaging; Neoplasm Recurrence, Local - pathology; Neoplasm Recurrence, Local - radiotherapy; Neoplasm Recurrence, Local - surgery; Positron Emission Tomography Computed Tomography; Proportional Hazards Models; Prostate - diagnostic imaging; Prostate - radiation effects; Prostate - surgery; Prostate-Specific Antigen - blood; Prostatectomy - adverse effects; Prostatic Neoplasms - diagnostic imaging; Prostatic Neoplasms - pathology; Prostatic Neoplasms - radiotherapy; Prostatic Neoplasms - surgery; Salvage Therapy - adverse effects
• ISSN: 0300-8916; 2038-2529
• DOI: 10.1177/0300891620908950

Objective: To assess the predictive role of response on dynamic contrast enhancement on magnetic resonance imaging (DCE-MRI) of visible local lesions in the setting of salvage radiotherapy (sRT) after radical prostatectomy. Methods: All patients referred for sRT for biochemical failure after radical prostatectomy from February 2014 to September 2016 were considered eligible if they had been restaged with DCE-MRI and had been found to have a visible lesion in the prostatic bed, but no distant/nodal disease on choline positron emission tomography (PET)–computed tomography (CT). Eligible patients were contacted during follow-up and offered reimaging with serial DCE-MRI until lesion resolution. Complete response (CR) was defined as the disappearance of the target lesion on DCE-MRI; prostate-specific antigen (PSA) recurrence was defined as a 0.2 ng/mL PSA rise above the nadir. Median follow-up after sRT was 41.5 months (range, 12.1–61.2 months). Results: Fifty-nine patients agreed to undergo repeated DCE-MRI for a total of 64 studied lesions. Overall, 57 lesions (89.1%) showed a CR after 1 (51 patients) or 2 (6 patients) scans, while 7 lesions did not show any change (no response [NR]). At 42 months, no evidence of biochemical disease (bNED) survival was 74.7±6.4% and 64.3±21.0% for patients with CR and NR lesions, respectively (hazard ratio [HR], 3.181; 95% confidence interval [CI], 0.157–64.364; p = 0.451). When only patients treated with sRT without androgen deprivation were selected (n = 41), bNED survival rates at 42 months were 72.1±8.0% and 0, respectively (HR, 52.830; 95% CI, 1.893–1474.110; p = 0.020). Conclusions: Patients whose lesions disappear during follow-up have a better outcome than those with unchanged lesions after sRT alone.