Radium-223 in metastatic hormone-sensitive high-grade prostate cancer: initial experience

Our study evaluates the feasibility of compassionate exemption of Radium-223 (223Ra) treatment in metastatic hormone-sensitive high-grade prostate cancer (mHSHGPC) patients with concomitant androgen deprivation-therapy (ADT).

Seven patients with mHSHGPC, were treated with six cycles of 223Ra plus ADT. All patients had undergone to 18F-NaF-PET/CT. A qualitative analyses of the 18F-NaF-PET/CT was performed in conjunction with Alkaline Phosphatase (ALP), Lactate-dehydrogenase (LDH) and Prostatic-Specific Antigen (PSA) values. The mean of SUVmax values were used as a quantitative measure of tumoral burden. Changes in PSA, ALP, LDH from baseline were evaluated, and were defined as increase or decrease of at least 30%. Clinical response was achieved if there was pain reduction using visual analogic scale. Four patients showed a significant reduction in mean SUVmax after 3 cycles of 223Ra, and one after 6 cycles. Patients who showed reductions in mean SUVmax after Ra-223 also showed reductions in PSA, ALP and LDH. Four weeks after the last cycle of 223Ra all patients had decreased total PSA, ALP and LDH values ≥ 30% also significant improvement on pain. No progress disease was documented after 14 ± 4 weeks. We found slight to moderate decreases in neutrophils and hemoglobin in two patients. We concluded that 223Ra plus ADT can be useful in mHSHGPC; the semi-quantitative 18F-NaF-PET/CT as a method effective to monitor the treatment response. Due to concomitant administration of ADT, 18F-NaF-PET/CT cannot differentiate whether the findings were due to androgen blockade or the 223Ra; nevertheless, data supporting the efficacy of 223Ra is the significant improvement on pain.

American journal of nuclear medicine and molecular imaging. 2017 Nov 01*** epublish ***

García-Pérez Francisco Osvaldo, Medina-Ornelas Sevastián Salvador, Santana-Ríos Zael, Sobrevilla-Moreno Nora

Nuclear Medicine and Molecular Imaging Department, Instituto Nacional de CancerologíaMexico City, Mexico., Urologic Malignances Department, Instituto Nacional de CancerologíaMexico City, Mexico., Oncology Department, Instituto Nacional de CancerologíaMexico City, Mexico.