Session Item

The purpose of the study is to report updated toxicity and oncological results at 5 years of the Phase II prospective trial "Give Me Five" short-term high precision radiotherapy for early prostate cancer with simultaneous boost to the dominant intraprostatic lesion (DIL) for patients with early stage prostate cancer (PCa) (AIRC-IG-13218).

“Give me Five” enrolled 65 patients since June 2015. Patients with low and intermediate risk PCa meeting the inclusion criteria underwent extreme hypofractionated radiotherapy to the prostate (36.25 Gy in 5 fractions) and a simultaneous integrated boost to the DIL of 37.5 Gy. The DIL was identified by a multiparamentric MRI (mpMRI) co-registered with the planning computed tomography (CT). Toxicity was assessed according to Common Terminology Criteria for Adverse Events (CTCAE) v4.0 and Radiation Therapy Oncology Group (RTOG) and the European Organization for Research and Treatment of Cancer (EORTC) criteria. All patients have been evaluated by a medical visit and/or phone call. Quality of life (QoL) of contacted and alive patients was assessed by International Prostate Symptoms score (IPSS), European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire—Core 30 (EORTC QLQ-C30), EORTC QLQ prostate specific (QLQ-PR25), and sexual activity by International Index of Erectile Function (IIEF-5). For all patients with no evidence of disease (NED), prostate-specific antigen (PSA) values were collected and analysed.

Five-year follow-up was available for 37 out of the 65 enrolled patients. After a median follow-up of 49 months (interquartile range, IQR 37-60 months), out of the 37 reachable patients, 27 (73%) resulted alive with NED, 3 (8%) alive with disease and 7 (19%) died for other causes. Biochemical progression-free survival at 5 years calculated on all patients and on patients still alive was 73% and 90%, respectively. Overall survival at 5 years was 81%. Out of the 27 NED patients, median PSA was 0.36 ng/ml (IQR 0.20-0.59 ng/ml). No grade (G)≥3 genitourinary and gastrointestinal toxicity events were reported. Questionnaires showed that overall QoL patients was satisfactory at last follow-up.

These updated data about efficacy and late toxicity of this extreme hypofractionated schedule with concomitant boost on the DIL confirm our previously published findings that it is a safe and effective approach. The increasing dose to the DIL does not worsen the RT toxicity and consequently does not affect patients' QoL, thus questioning the possibility of an even more escalated treatment.