11C Choline PET Guided Salvage Radiotherapy with Volumetric Modulation Arc Therapy and Hypofractionation for Recurrent Prostate Cancer after HIFU Failure: Preliminary Results of Tolerability and Acute Toxicity

Abstract

The purpose of this work was to evaluate tolerance, feasibility and acute toxicity in patients undergoing salvage radiotherapy after high-intensity focused ultrasound (HIFU) failure. From 2005 to 2011 a total of 15 patients were treated with HIFU as primary radical treatment. Between July 2011 and February 2013, all 15 patients presented biochemical relapse after HIFU and 11C choline PET documenting intrapostatic-only failure. Salvage EBRT was performed with moderate hypofractionation schedule in 28 fractions with volumetric modulation arc therapy (VMAT). Genito-urinary (GU) and rectal and bowel toxicity were scored by common terminology criteria for adverse events version 4 (CTCAE V.4) scale. Biochemical response was assessed by ASTRO Phoenix criteria. Median age of patients was 67 years (range: 53-85). The median Gleason score was 7 (range: 6-9). The median prostate specific antigen (PSA) at the time of biochemical relapse after HIFU was 5.2 ng/mL (range: 2-64.2). Seven of the 15 patients received androgen deprivation therapy (ADT) started after HIFU failure, interrupted before 11C choline PET and radiotherapy. Median prescribed dose was 71.4 Gy (range: 71.4-74.2 Gy) in 28 fractions. No radiation related major upper gastrointestinal (GI), rectal and GU toxicity were experienced. GU, acute grade 1 and grade 2 toxicities were recorded in 7/15 and 4/15 respectively; bowel acute grade 1 and grade 2 toxicities in 4/15 and 1/15; rectal acute grade 1 and grade 2 toxicities in 3/15 and 2/15 respectively. No grade 3 or greater acute or late toxicities occurred. Biochemical control was assessed in 12/15 (80%) patients. With a median follow up of 12 months, three out of 15 patients, with biochemical relapse, showed lymph-nodal recurrence. Our early clinical results and biochemical data confirm the feasibility and show a good tolerance of the 11C choline PET guided salvage radiation therapy after HIFU failure. The findings of low acute toxicity is encouraging, but longer follow-up is needed to assess late toxicity and definitive outcomes.

Whole Body Microwave Irradiation for Improved Dacarbazine Therapeutical Action in Cutaneous Melanoma Mouse Model

“…HIFU therapy has been used in Japan [ 50 ], but in other countries this therapy has been reported with contradictory results, sometimes failing [ 51 ] and sometimes showing improved results in secondary hyperparathyroidism treatment in patients with chronic kidney disease [ 52 ]. More radical negative results were published this year when all the prostate cancer patients treated with HIFU relapsed after approximately 6 years after HIFU treatment [ 53 ]. The conclusion of the results published until now using HIFU is the need to accumulate more clinical experience in this type of treatment.…”

Salvage radiotherapy following HiFU: An institutional series and literature review

“…reported a range of 3–136 months between HiFU and salvage RT with a median of 39 months. Median time to salvage therapy was also around 30 months in a few other studies, 10–12 while others more consistently showed 12–15 months 13–17 . Importantly, the median PSA values prior to salvage therapies also varied greatly, with a broad range of values reported by certain studies ( e.g .…”

The ability of 18F-choline PET/CT to identify local recurrence of prostate cancer

“…In this subgroup of patients, PSAdt and PSAvel were significantly higher than those with lymph node or distant metastases. Alongi et al [40] analyzed 15 patients who underwent salvage EBRT due to a biochemical recurrence after high intensity focused ultrasound (HIFU). In these selected patients, 11C-Choline showed a positive intraprostatic-alone failure, thus being able to give information about the target definition in salvage EBRT, although it would still be considered an experimental procedure.…”