The Phase I/II trial will prospectively assess the acute, early late and late gastrointestinal (GI), genitourinary (GU) and sexual toxicity of combined hypofractionated external beam radiation therapy (EBRT) plus high dose-rate brachytherapy (HDR-BT) schedule (total dose of EBRT 36 Gy/ in 12 fractions of 3 Gy plus HDR-BT with a total physical dose of 14 Gy in a single fraction) for patients with unfavourable intermediate/high risk (based on NCCN stratification guidelines) organ-confined prostate cancer, not requiring pelvic irradiation.