High dose rate brachytherapy for prostate cancer: A prospective toxicity evaluation of a one day schedule including two 13.5 Gy fractions.

High dose-rate (HDR) brachytherapy (BT) provides a highly conformal method of dose delivery to the prostate. The purpose of this study is to prospectively determine the toxicity of the treatment protocol of 13. 5 Gy × 2 fractions.

From 2010 through 2017, 119 patients with low (71%) or intermediate-risk prostate cancer were prospectively treated in a single institute with HDR-BT at 13.5 Gy × 2 fractions within one day. Median follow-up time was 4.4 years.

Actuarial rates of no biochemical evidence of disease, overall survival and metastasis-free survival for all patients were 96%,98% and 98%, respectively. The cumulative incidence of acute grade 2 and 3 genitourinary (GU) toxicity was 9% and 2%, respectively. The corresponding incidences of late GU toxicity were 18% and 1%. No grade ≥4 of either type of toxicity was detected. Multivariate analysis showed that having higher international prostate symptom score (IPSS; P = 0.041) or higher V200 (P = 0.013) was associated with a higher risk of experiencing any grade of acute GU toxicity. In addition, patients having a higher IPSS (P = 0.019) or a higher V150 (P = 0.033) were associated with a higher grade >1 acute GU toxicity.

The findings of this study show that HDR-BT 13.5 Gy × 2 as monotherapy was safe and effective for prostate cancer patients with low-intermediate risk.

Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology. 2018 Apr 03 [Epub]

Gorka Nagore, Jose Luis Lopez Guerra, Evita Krumina, Mark Lagos, Beatriz Ovalles, Antonio Miró, Lourdes Beltran, Emilia Gómez, Juan Manuel Praena-Fernandez, Eleonor Rivin Del Campo, Ignacio Azinovic, Alfonso Gomez-Iturriaga

Department of Radiation Oncology, GenesisCare, Alicante, Spain., Department of Radiation Oncology, University Hospital Virgen del Rocio, Seville, Spain. Electronic address: ., Methodology Unit, University Hospital Virgen del Rocio, Seville, Spain., Department of Radiation Oncology, Tenon University Hospital, Paris, France., Department of Radiation Oncology, GenesisCare, Madrid, Spain., Department of Radiation Oncology, Hospital Universitario Cruces-Biocruces Health Research Institute, Barakaldo, Spain.