Dose-escalation using intensity-modulated radiotherapy for prostate cancer - evaluation of quality of life with and without 18F-choline PET-CT detected simultaneous integrated boost

Abstract

BackgroundIn comparison to the conventional whole-prostate dose escalation, an integrated boost to the macroscopic malignant lesion might potentially improve tumor control rates without increasing toxicity. Quality of life after radiotherapy (RT) with vs. without 18F-choline PET-CT detected simultaneous integrated boost (SIB) was prospectively evaluated in this study.MethodsWhole body image acquisition in supine patient position followed 1 h after injection of 178-355MBq 18F-choline. SIB was defined by a tumor-to-background uptake value ratio > 2 (GTVPET). A dose of 76Gy was prescribed to the prostate (PTVprostate) in 2Gy fractions, with or without SIB up to 80Gy. Patients treated with (n = 46) vs. without (n = 21) SIB were surveyed prospectively before (A), at the last day of RT (B) and a median time of two (C) and 19 month (D) after RT to compare QoL changes applying a validated questionnaire (EPIC - expanded prostate cancer index composite).ResultsWith a median cut-off standard uptake value (SUV) of 3, a median GTVPET of 4.0 cm3 and PTVboost (GTVPET with margins) of 17.3 cm3 was defined. No significant differences were found for patients treated with vs. without SIB regarding urinary and bowel QoL changes at times B, C and D (mean differences ≤3 points for all comparisons). Significantly decreasing acute urinary and bowel score changes (mean changes > 5 points in comparison to baseline level at time A) were found for patients with and without SIB. However, long-term urinary and bowel QoL (time D) did not differ relative to baseline levels - with mean urinary and bowel function score changes < 3 points in both groups (median changes = 0 points). Only sexual function scores decreased significantly (> 5 points) at time D.ConclusionsTreatment planning with 18F-choline PET-CT allows a dose escalation to a macroscopic intraprostatic lesion without significantly increasing toxicity.

Developments in External Beam Radiotherapy for Prostate Cancer

“…20 Few studies have reported on the outcome after delivering SIB-IMRT. [20][21][22] Fonteyne et al detected an IPL in 118 of 221 PC patients using MRI and MRS. Median dose delivered to the prostate and the IPL was 78 Gy and 81 Gy respectively in 38 fractions.…”

Current status of choline‐PET and prostate cancer

“…Pinkawa et al 32 have demonstrated the feasibility of using 18 F-choline-PET/CT to allow dose escalation using a simultaneous integrated boost during radical radiotherapy, although the long-term survival data from such an approach is unknown. Vees et al 33 combined 99m Tc-Nanocoll prostatic sentinel lymph node detection using SPECT/CT with 18 F-choline-PET/CT in 20 men with high-risk prostate cancer; 40 per cent of patients had nodal involvement outside the standard pelvic radiotherapy target volume, highlighting that this approach may allow for tailoring of the radiotherapy treatment volume.…”

Molecular Imaging to Plan Radiotherapy and Evaluate Its Efficacy

“…Studies have been performed on the brain using 18 F-FDG (65) and O-(2-18 F-fluoroethyl)-L-tyrosine PET (66), on head-and-neck tumors using 18 F-FDG PET (67-69), on prostate tumors using 18 F-fluorocholine PET (70), and on lung tumors using 18 F-FDG PET (71). Further clinical studies are ongoing.…”