Efficacy and toxicity of primary re-irradiation for malignant spinal cord compression based on radiobiological modelling: a phase II clinical trial.

BACKGROUND: The efficacy and safety of primary re-irradiation for MSCC are not known. Our aim was to establish the efficacy and safety of biologically effective dose-based re-irradiation. METHODS: Patients presenting with MSCC at a previously irradiated spine segment, and not proceeding with surgical decompression, were eligible. A 3 Gray per fraction experimental schedule (minimum 18 Gy/6 fractions, maximum 30 Gy/10 fractions) was used, delivering a maximum cumulative spinal dose of 100 Gy2 if the interval since the last radiotherapy was within 6 months, or 130 Gy2 if longer. The primary outcome was a change in mobility from week 1 to week 5 post-treatment, as assessed by the Tomita score. The RTOG SOMA score was used to screen for spinal toxicity, and an MRI performed to assess for radiation-induced myelopathy (RIM). RESULTS: Twenty-two patients were enroled, of whom eleven were evaluable for the primary outcome. Nine of eleven (81.8%) had stable or improved Tomita scores at 5 weeks. One of eight (12.5%) evaluable for late toxicity developed RIM. CONCLUSIONS: Re-irradiation is an efficacious treatment for MSCC. There is a risk of RIM with a cumulative dose of 120 Gy2. CLINICAL TRIAL REGISTRATION: Cancer Trials Ireland (ICORG 07-11); NCT00974168.

Non-inferiority randomised phase 3 trial comparing two radiation schedules (single vs. five fractions) in malignant spinal cord compression.

BACKGROUND: The optimal EBRT schedule for MSCC is undetermined. Our aim was to determine whether a single fraction (SF) was non-inferior to five daily fractions (5Fx), for functional motor outcome. METHODS: Patients not proceeding with surgical decompression in this multicentre non-inferiority, Phase 3 trial were randomised to 10 Gy/SF or 20 Gy/5Fx. A change in mobility from baseline to 5 weeks for each patient, was evaluated by a Modified Tomita score: 1 = 'Walk unaided', 2 = 'With walking aid' and 3 = 'Bed-bound'. The margin used to establish non-inferiority was a detrimental change of -0.4 in the mean difference between arms. RESULTS: One-hundred and twelve eligible patients were enrolled. Seventy-three patients aged 30-87 were evaluated for the primary analysis. The 95% CI for the difference in the mean change in mobility scores between arms was -0.12 to 0.6. Since -0.4 is not included in the interval, there is evidence that 10 Gy/SF is non-inferior to 20 Gy/5Fx. One grade 3 AE was reported in the 5Fx arm. Twelve (26%) patients in the 5Fx arm had a Grade 2-3 AE compared with six (11%) patients in the SF arm (p = 0.093). CONCLUSION: For mobility preservation, one 10-Gy fraction is non-inferior to 20 Gy in five fractions, in patients with MSCC not proceeding with surgical decompression. CLINICAL TRIAL REGISTRATION: Cancer Trials Ireland ICORG 05-03; NCT00968643; EU-20952.

Temporal patterns of late bowel and bladder radiotherapy toxicity in a randomised controlled trial assessing duration of neo-adjuvant hormones in prostate cancer.

BACKGROUND: To assess the temporal patterns of late gastrointestinal (GI) and genitourinary (GU) radiotherapy toxicity and resolution rates in a randomised controlled trial (All-Ireland Cooperative Oncology Research Group 97-01) assessing duration of neo-adjuvant (NA) hormone therapy for localised prostate cancer. MATERIAL AND METHODS: Node negative patients with > 1 of: PSA > 20 ng/mL, Gleason score ≥ 7, and stage T3 or more, were included. Follow-up, including toxicity assessment, was three-monthly in the early stages and yearly thereafter. RESULTS: Median follow-up from the end of RT was 6.8 years. In the interval between 90 days following the end of RT and the last toxicity assessment, GI and GU toxicity (any grade) was found in 50% and 51% of 240 and 241 patients, respectively. For those who did develop toxicity, the median time from end of RT until the first development of any grade GI or GU toxicity was 1.2 years and 1.6 years, respectively, whilst median time to final resolution was 1.6 years and 2.2 years, respectively. Grade 2 (G2) or greater GI and GU toxicity occurred in 29 (12.1%) and 40 (16.6%) patients, respectively. The proportion with unresolved G2 + GI and GU toxicity was 89% and 79%, respectively, in year 1, 69% and 65% in year 2, 59% and 52% in year 3 and 27% and 32% in year 5. CONCLUSION: Long-term toxicities continue to occur many years after NA hormone therapy and RT. The rate of occurrence does not appear to reduce within the time frame during which our patients were followed. The percentage of patients suffering from G2 + toxicity at any time is however low. Resolution of these toxicities continues for the duration of the follow-up.

Radium-223 in combination with enzalutamide in metastatic castration-resistant prostate cancer: a multi-centre, phase II open-label study.

BACKGROUND: Radium-223 and enzalutamide are approved agents for patients with metastatic castration-resistant prostate cancer (mCRPC). Combining radium-223 and enzalutamide to improve outcomes is of clinical interest due to their differing modes of action and non-overlapping toxicity profiles. METHODS: This phase II study enrolled patients with mCRPC and bone metastases. Patients received six cycles of radium-223 in combination with enzalutamide, followed by enzalutamide alone. The primary endpoint was safety for the combination; secondary endpoints included radiographic/clinical progression-free survival (PFS), PSA PFS, overall survival (OS), change in alkaline phosphatase, patient-reported pain outcomes and skeletal related events. RESULTS: Forty-five patients received the combination treatment: 42 patients (93.3%) received all six cycles. Fourteen patients (31.1%) developed grade 3 or 4 toxicities, most commonly fatigue and neutropaenia. Fractures during the combination period occurred in four patients (8.9%). A further 13 patients (28.9%) developed fractures after completing combination treatment, giving a total of 17 patients (37.8%) who developed a fracture at any time on study. The median time to fracture was greater than 17.2 months [95% confidence interval (CI), 17.2-not estimable]. The median time to PSA progression was 18.1 months (95% CI, 12.68-22.60) and the median time to radiological/clinical progression was 28.0 months (95% CI, 22.54-not reached). At the primary analysis, 19 (42.2%) out of 45 patients had died with a median OS not reached (mean 34.8 months, standard error 1.4). CONCLUSION: In men with progressive mCRPC and bone metastases, the combination of radium-223 and enzalutamide was tolerable with the majority of patients completing the combination treatment. Bone fractures during the combination period were uncommon; however, we did identify a higher incidence of fractures occurring in patients after completing combination treatment. Bone health agents should be administered and bone health should be closely monitored following treatment with radium-223 and enzalutamide.

A comparison of bladder volumes based on treatment planning CT and BladderScan® BVI 6100 ultrasound device in a prostate radiation therapy population.

OBJECTIVE:: The aim of this study is to investigate if a handheld ultrasound device (BladderScan® BVI 6100) can accurately measure bladder volumes in prostate radiotherapy (RT) patients. METHODS:: A comparison was made of contoured bladder volumes based on treatment planning CT (TPCT) and BladderScan® BVI 6100 ultrasound device in a large prostate RT population. Three bladder volume (BV) measurements were taken using the bladder volume instrument (BVI) device on prostate RT patients immediately prior to TPCT (n = 190). The CT delineation bladder volumes were also recorded. The mean of the three BVI readings (BVImean) and the maximum (BVImax) of the readings were considered for a comparative analysis. RESULTS:: There was a strong positive correlation between the BVI and CT delineated bladder volumes (BVImean r = 0.825; BVImax r = 0.830). The mean difference [± standard deviation (SD)] was an underestimation of BV for both BVImean and BVImax (44.8 ± 88.2 ml and 32.9 ± 87.5 ml, respectively). CONCLUSION:: This is the largest study to date (n = 190), assessing the accuracy of the BladderScan® BVI 6100 in the prostate RT population. The BVI 6100 provides an acceptable indication of BV for use in prostate RT patients for the purposes of monitoring BV. ADVANCES IN KNOWLEDGE:: The BladderScan® BVI 6100 provides a convenient and non-irradiating method of indicating BV for use in prostate RT patients.

A randomized trial comparing bladder volume consistency during fractionated prostate radiation therapy.

PURPOSE: Organ motion is a contributory factor to the variation in location of the prostate and organs at risk during a course of fractionated prostate radiation therapy (RT). A prospective randomized controlled trial was designed with the primary endpoint to provide evidence-based bladder-filling instructions to achieve a consistent bladder volume (BV) and thus reduce the bladder-related organ motion. The secondary endpoints were to assess the incidence of acute and late genitourinary (GU) and gastrointestinal (GI) toxicity for patients and patients' satisfaction with the bladder-filling instructions. METHODS AND MATERIALS: One hundred ten patients were randomly assigned to 1 of 2 bladder-filling protocols; 540 mL (3 cups) of water or 1080 mL (6 cups) of water, in a single institution trial. A portable ultrasound device, BladderScan BVI 6400 (Verathon Inc, Bothell, WA), measured BVs at treatment planning computed tomography (TPCT) scan and 3 times per week during RT. Maximum bladder dose and BV receiving ≥ 50, 60, and 70 Gy were recorded. Acute and late GU and GI toxicity were evaluated, as were patients' comfort, perception of urinary symptoms, and quality of life (QoL). RESULTS: There was significantly less BV variation in the 540 mL arm when compared with 1080 mL (median: 76 mL vs 105 mL, P = .003). Larger BVs on initial TPCT correlated with larger BV variations during RT (P < .0005). There were no statistically significant associations between arm and GU/GI toxicity, dose median comfort scores, or median QoL scores. CONCLUSIONS: The 540 mL bladder-filling arm resulted in reproducible BVs throughout a course of RT, without any deterioration in QoL or increase in toxicities for prostate patients.

A randomized trial (Irish clinical oncology research group 97-01) comparing short versus protracted neoadjuvant hormonal therapy before radiotherapy for localized prostate cancer.

PURPOSE: To examine the long-term outcomes of a randomized trial comparing short (4 months; Arm 1) and long (8 months; Arm 2) neoadjuvant hormonal therapy before radiotherapy for localized prostate cancer. METHODS AND MATERIALS: Between 1997 and 2001, 276 patients were enrolled and the data from 261 were analyzed. The stratification risk factors were prostate-specific antigen level >20 ng/mL, Gleason score≥7, and Stage T3 or more. The intermediate-risk stratum had one factor and the high-risk stratum had two or more. Staging was done from the bone scan and computed tomography findings. The primary endpoint was biochemical failure-free survival. RESULTS: The median follow-up was 102 months. The overall survival, biochemical failure-free survival. and prostate cancer-specific survival did not differ significantly between the two treatment arms, overall or at 5 years. The cumulative probability of overall survival at 5 years was 90% (range, 87-92%) in Arm 1 and 83% (range, 80-86%) in Arm 2. The biochemical failure-free survival rate at 5 years was 66% (range, 62-71%) in Arm 1 and 63% (range, 58-67%) in Arm 2. CONCLUSION: No statistically significant difference was found in biochemical failure-free survival between 4 months and 8 months of neoadjuvant hormonal therapy before radiotherapy for localized prostate cancer.