UK & Ireland Prostate Brachytherapy Practice Survey 2014-2016

Purpose: To document the current prostate brachytherapy practice across the UK and Ireland and compare with previously published audit results. Material and methods: Participants from 25 centers attending the annual UK & Ireland Prostate Brachytherapy Conference were invited to complete an online survey. Sixty-three questions assessed the center’s experience and staffing, clinician’s experience, clinical selection criteria and scheduling, number of cases per modality in the preceding three years, low-dose-rate (LDR) pre- and post-implant technique and high-dose-rate (HDR) implant technique. Responses were collated, and descriptive statistical analysis performed. Results: Eighteen (72%) centers responded with 17 performing LDR only, 1 performing HDR only, and 6 performing both LDR and HDR. Seventy-one percent of centers have > 10 years of LDR brachytherapy experience, whereas 71% centers that perform HDR brachytherapy have > 5 years of experience. Thirteen centers have 2 or more clinicians performing brachytherapy with 61% of lead consultants performing > 25 cases (LDR + HDR) in 2016. The number of implants (range), that includes LDR and HDR, performed by individual practitioners in 2016 was > 50 by 21%, 25-50 by 38%, and < 25 by 41%. Eight centers reported a decline in LDR monotherapy case numbers in 2016. Number of center’s performing HDR brachytherapy increased in last five years. Relative uniformity in patient selection is noted, and LDR pre- and post-implant dosimetry adheres to published quality guidelines, with an average post-implant D90 of > 145 Gy in 69% of centers in 2014 and 2015 compared to 63% in 2016. The median CT/US volume ratios were > 0.9 ≤ 1.0 (n = 4), > 1.0 ≤ 1.1 (n = 7), and > 1.1 (n = 2). Conclusion: There is considerable prostate brachytherapy experience in the UK and Ireland. An apparent fall in LDR case numbers is noted. Maintenance of case numbers and ongoing compliance with published quality guidelines is important to sustain high quality outcomes

Prostate cancer treated with brachytherapy; an exploratory study of dose-dependent biomarkers and quality of life

BACKGROUND: Low-dose-rate permanent prostate brachytherapy (PPB) is an attractive treatment option for patients with localised prostate cancer with excellent outcomes. As standard CT-based post-implant dosimetry often correlates poorly with late treatment-related toxicity, this exploratory (proof of concept) study was conducted to investigate correlations between radiation − induced DNA damage biomarker levels, and acute and late bowel, urinary, and sexual toxicity. METHODS: Twelve patients treated with (125)I PPB monotherapy (145Gy) for prostate cancer were included in this prospective study. Post-implant CT based dosimetry assessed the minimum dose encompassing 90% (D(90%)) of the whole prostate volume (global), sub-regions of the prostate (12 sectors) and the near maximum doses (D(0.1cc), D(2cc)) for the rectum and bladder. Six blood samples were collected from each patient; pre-treatment, 1 h (h), 4 h, 24 h post-implant, at 4 weeks (w) and at 3 months (m). DNA double strand breaks were investigated by staining the blood samples with immunofluorescence antibodies to γH2AX and 53BP1 proteins (γH2AX/53BP1). Patient self-scored quality of life from the Expanded Prostate Cancer Index Composite (EPIC) were obtained at baseline, 1 m, 3 m, 6 m, 9 m, 1 year (y), 2y and 3y post-treatment. Spearman’s correlation coefficients were used to evaluate correlations between temporal changes in γH2AX/53BP1, dose and toxicity. RESULTS: The minimum follow up was 2 years. Population mean prostate D(90%) was 144.6 ± 12.1 Gy and rectal near maximum dose D(0.1cc) = 153.0 ± 30.8 Gy and D(2cc) = 62.7 ± 12.1 Gy and for the bladder D(0.1cc) = 123.1 ± 27.0 Gy and D(2cc) = 70.9 ± 11.9 Gy. Changes in EPIC scores from baseline showed high positive correlation between acute toxicity and late toxicity for both urinary and bowel symptoms. Increased production of γH2AX/53BP1 at 24 h relative to baseline positively correlated with late bowel symptoms. Overall, no correlations were observed between dose metrics (prostate global or sector doses) and γH2AX/53BP1 foci counts. CONCLUSIONS: Our results show that a prompt increase in γH2AX/53BP1foci at 24 h post-implant relative to baseline may be a useful measure to assess elevated risk of late RT − related toxicities for PPB patients. A subsequent investigation recruiting a larger cohort of patients is warranted to verify our findings. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13014-017-0792-1) contains supplementary material, which is available to authorized users