Hemi-ablative low-dose-rate prostate brachytherapy for unilateral localised prostate cancer.

OBJECTIVES: To report clinical outcomes of the Hemi-Ablative Prostate Brachytherapy (HAPpy) trial evaluating treatment-related toxicity and effectiveness of hemi-gland (HG) low-dose-rate (LDR) prostate brachytherapy as a focal approach to control unilateral localised prostate cancer. PATIENTS AND METHODS: Single institution phase IIS pilot study of patients treated with focal 4D Brachytherapy™ (BXTAccelyon, Burnham, Buckinghamshire, UK). The primary outcome was patient-reported toxicity 24 months after implant. The secondary outcome was assessment of disease control. Outcomes in HG patients were compared to whole-gland (WG) controls obtained from our prospective cohort registry by negative binomial and linear regression models. RESULTS: Pre-treatment demography was similar between the 30 HG patients and 362 WG controls. Post-implant dosimetry was similar for the prostate gland target volumes and significantly reduced for the urethra and bowel in HG patients relative to WG controls, but this did not translate into a difference in post-implant mean symptom scores between the two groups. Nevertheless, the change in score from baseline indicated that the impact on pre-treatment symptom status was less after HG implants. Only HG patients showed a return to baseline urinary scores as early as 12 months. Sexual potency was conserved in 73% and 67% of HG and WG patients, respectively (P = 0.84). Post-implant prostate-specific antigen (PSA) kinetics revealed that baseline PSA was reduced at 24 months by 78% and 88% in HG and WG patients, respectively (P < 0.05). Treatment relapse occurred in one (3%) HG patient 55 months after implant and in nine (3%) WG patients at 32-67 months after implant. CONCLUSION: This pilot study suggests that treatment-related toxicity and biochemical outcomes after HG implants are broadly similar to those observed with WG treatment despite the lower dose delivered by HG implants.

Pain and symptom relief using inhaled methoxyflurane for gynecologic brachytherapy applicator removal.

Purpose: Intra-cavitary brachytherapy forms an essential part of the curative treatment of cervical and vaginal cancer, and can be used for cure or palliation in endometrial and vulval cancers. Removal of brachytherapy applicators is often performed after anaesthesia has worn off and can be an uncomfortable and anxiety-provoking procedure. In this paper, we present our experience in a series of patients before and after the introduction of inhaled methoxyflurane (IMF, Penthrox™). Material and methods: Questionnaires were sent to patients prior to the introduction of IMF to retrospectively score pain and anxiety during the brachytherapy procedure. Following successful review by the local drugs and therapeutic committee as well as staff training, IMF was introduced and offered to patients during applicator removal. Prospective pain scores and retrospective questionnaires were collected. Pain was rated on a scale of 0 to 10, with zero being no pain and 10 being extreme pain. Results: Thirteen patients returned retrospective questionnaires prior to IMF introduction and seven patients following IMF introduction. After the first brachytherapy insertion, the mean recollected pain score during applicator removal decreased from 6/10 to 1/10 (p = 0.002). The mean recollected pain score one hour after applicator removal reduced from 3/10 to 0 (p = 0.04). Prospective measurements for 77 insertions in 44 patients receiving IMF reported a median pain score of 1/10 immediately before applicator removal (range, 0-10), and 0/10 immediately after applicator removal (range, 0-5). Conclusions: Inhaled methoxyflurane is easily administered and effective method of decreasing pain during applicator removal following gynecologic brachytherapy.

Planned organ preservation for elderly patients with rectal cancer using short course radiotherapy and a contact brachytherapy boost-an International multi-institution analysis.

Background and purpose: The use of external beam radiotherapy (EBRT) and contact X-Ray brachytherapy (CXB) is emerging as an effective alternative in patients with early stage rectal cancer with the intent of organ preservation (OP). Short course radiotherapy (SCRT) is an alternative EBRT schedule for patients not fit for chemotherapy or for longer courses of EBRT. There are no multicentre studies that have reported on the outcomes of SCRT with a CXB boost, therefore we present these from patients from centres from the UK and Sweden. Materials and methods: From the Guildford Colorectal Database or local databases, 258 patients who underwent SCRT and CXB with the intent of OP from five centres treated between 2007 and 2019 were identified. Response and survival data was analysed and presented. Results: With a median age of 81, 226 patients were treated with radiotherapy alone (RTA) and 32 immediately after local excision (ILE). Median follow-up was 24 months. 70% and 97% of patients in the RTA and ILE groups respectively had a complete clinical response (cCR) after SCRT with CXB. Of those, local relapse was seen in 16% of the RTA and 3% of the ILE group. Median survival was 40 months after CXB in the RTA and 52 months in the ILE group. 94% of patients remained stoma-free to the point of latest follow-up. Conclusion: This data suggests that CXB when combined with SCRT, in a mainly elderly and comorbid population, provides good palliation with stoma-avoidance. Oncological outcomes compare with previously published work. A greater focus is required on quality of life outcomes after OP.

Improving dose delivery by adding interstitial catheters to fixed geometry applicators in high-dose-rate brachytherapy for cervical cancer.

PURPOSE: Image-guided brachytherapy (IGBT) is an essential component of the treatment of locally advanced cervical cancer. Interstitial (IS) catheters are being increasingly used for bulkier tumors. We have retrospectively assessed the dosimetric impact of IS catheters. METHODS AND MATERIALS: All patients who received IGBT for cervical cancer between August 2014 and February 2017 were identified. Clinical and dosimetric data were collected. Patients were grouped into the intracavitary (IC) cohort or the IC and IS implant (IC/IS) cohort. Ten patients who had been treated with IS catheters (IC/IS plan) had their brachytherapy replanned without IS catheters (IC plan). The total D90% received by the high-risk clinical target volume (CTVHR) and the D2cm3 (minimum dose received by the most irradiated 2 cm3) to the bladder, bowel, sigmoid, and rectum were compared. RESULTS: Forty-two patients received IGBT in this period. Seventy-four percent of patients were treated with IS catheters. Sixty-one percent of patients in the IC/IS cohort had CTVHR volumes ≥30 cm3 at Fraction 1 compared to 18% in the IC cohort (p = 0.014). There was no difference in cumulative D90% to CTVHR between the IC/IS cohort and the IC cohort. The replanned brachytherapy showed that the cumulative CTVHRD90% was on average 5.8 Gy higher when IS catheters were used (mean CTVHRD90% 86.1 compared to 80.3 Gy, p < 0.001). The D2cm3 to the organs at risk was not significantly increased. CONCLUSIONS: IS catheters allow the dose to the CTVHR to be escalated significantly without increasing the dose to the bladder, bowel, sigmoid, and rectum in patients with bulky tumors.

Improving the efficiency of image guided brachytherapy in cervical cancer.

Brachytherapy is an essential component of the treatment of locally advanced cervical cancers. It enables the dose to the tumor to be boosted whilst allowing relative sparing of the normal tissues. Traditionally, cervical brachytherapy was prescribed to point A but since the GEC-ESTRO guidelines were published in 2005, there has been a move towards prescribing the dose to a 3D volume. Image guided brachytherapy has been shown to reduce local recurrence, and improve survival and is optimally predicated on magnetic resonance imaging. Radiological studies, patient workflow, operative parameters, and intensive therapy planning can represent a challenge to clinical resources. This article explores the ways, in which 3D conformal brachytherapy can be implemented and draws findings from recent literature and a well-developed hospital practice in order to suggest ways to improve the efficiency and efficacy of a brachytherapy service. Finally, we discuss relatively underexploited translational research opportunities.

Hemi-gland focal low dose rate prostate brachytherapy: An analysis of dosimetric outcomes.

BACKGROUND AND PURPOSE: Advances in magnetic resonance imaging (MRI) and prostate sampling enable early identification of men with low to intermediate risk prostate cancer who are candidates for focal therapies that minimise side effects. We report dosimetry data from a pilot study evaluating the effectiveness of hemi-gland low dose rate (HG-LDR) brachytherapy as a focal therapy approach to control unilateral localised disease. MATERIAL AND METHODS: Twenty-two men underwent HG-LDR brachytherapy. Multi parametric MRI and transperineal template mapping biopsies were used to identify low volume unilateral disease. Whole gland therapy controls (n=120) were retrospectively obtained. All implants were performed with 4D Brachytherapy. RESULTS: Intraoperative and postimplant dosimetry complied with established brachytherapy parameters. Mean (standard deviation) postoperative D90 for the target hemi-gland was 153.8 (11.3) Gy compared to 47.5 (12.7) Gy for the contralateral hemi-gland (P<0.001). Mean postoperative V100% was 93.1 (3.9) and 24.6 (10.5) for the target and contralateral hemi-glands respectively (P<0.001). Urethra D30 was 150.4 (19.8) Gy and 174.2 (15.0) Gy for hemi-gland and whole gland implants respectively (P<0.001). Significantly reduced dose was also observed for rectum and neurovascular bundles. CONCLUSIONS: HG-LDR focal brachytherapy is feasible with significant reduction in dose to the contralateral hemi-gland and organs at risk.