Recruitment

Recruitment Status
Completed
Estimated Enrollment
60

Inclusion Criterias

ECOG performance status 0-2
International Prostate Symptom Score (I-PSS) score <15
Histologically proven prostate adenocarcinoma
...
ECOG performance status 0-2
International Prostate Symptom Score (I-PSS) score <15
Histologically proven prostate adenocarcinoma
No contraindication to MRI (pacemaker, severe claustrophobia)
PSA obtained within three months prior to enrollment.
Ability to understand and the willingness to sign a written informed consent document.
Patient must be able to have fiducial markers placed in the prostate (if on anticoagulants, must be cleared by LMO or cardiologist).

Exclusion Criterias

Previous pelvic radiotherapy
Prior total prostatectomy
Unwilling or unable to give informed consent
...
Previous pelvic radiotherapy
Prior total prostatectomy
Unwilling or unable to give informed consent
Unwilling or unable to complete quality of life questionnaires.

Summary

Conditions
Prostate Cancer
Type
Interventional
Design
  • Allocation: N/A
  • Intervention Model: Single Group Assignment
  • Masking: None (Open Label)
  • Primary Purpose: Treatment

Participation Requirements

Age
Between 35 years and 85 years
Gender
Only males

Description

Prostate cancer accounts for one third of all new cancer diagnoses in men and approximately 30% of men will have External Beam Radiotherapy (EBRT) as primary local therapy. Local persistence of prostate cancer treated with radiotherapy is under-appreciated. Prostate cancer has a long natural history...

Prostate cancer accounts for one third of all new cancer diagnoses in men and approximately 30% of men will have External Beam Radiotherapy (EBRT) as primary local therapy. Local persistence of prostate cancer treated with radiotherapy is under-appreciated. Prostate cancer has a long natural history and the consequences of local persistence may not be realized for many years. Prostate cancer has a slow growth with a potential doubling time ranging from weeks to months (median 42 days) which has led to the hypothesis that prostate cancer will behave more like a late reacting tissue(1). Brenner et al. (2) used data from prostate Low Dose Rate (LDR) permanent seed implants and EBRT series to derive an alpha/beta of approximately 1.5. Many groups have also calculated the alpha/beta ratio to be in the < 3.0 range(3). If the alpha/beta ratio for prostate cancer is lower than the surrounding normal tissues (Brenner et al. have estimated the alpha/beta for the rectum to be over 5.0), doses greater than 2 Gy (hypofractionation) will afford an advantage as there will be a greater sensitivity of prostate cancer to radiation, as compared to the bladder or rectum. This benefit has been exploited for many years with High Dose Rate (HDR) brachytherapy using Iridium -192. Typical doses for HDR are 19Gy in two fractions in addition to 46Gy in 23 fractions of EBRT (4). With reference to our own institutional data from HDR brachytherapy we calculated the dose distribution in recently treated patients. Due to the nature of the iridium dose distribution, there are considerable areas of much higher dose delivered; 200% of the dose (38Gy) to 12.7% of the target volume, 150% (13.75Gy) to 32.6% of the target volume and 125% (11.9Gy) to 60.1% of the target. Despite the high doses to the periphery of the prostate it is possible to limit the dose to the rectum and bladder to 1cc < 75% (14.25Gy) and the 1cc urethra to <125% (23.75Gy) (4). HDR brachytherapy series have reported durable long term Biochemical Failure Free Survival (BFFS), which are as good or better than comparable external beam or surgical series(5). However despite the low toxicity and excellent biochemical outcomes, HDR brachytherapy utilization in Australia is low, with under 300 cases in total per year. This is due to the logistical difficulty of HDR brachytherapy, anaesthetic requirements, nursing care and patient discomfort. There have been five published studies investigating stereotactic boost in addition to standard fractionation EBRT without using brachytherapy, four reports with the Cyberknife platform (6-9) and one with Intensity Modulated Radiotherapy (IMRT) (10). All of these series have early follow up (FU) with reported BFFS between 77% and 100%. The largest experience is from Katz et al. (8) who reported 73 patients with both intermediate (n= 41) and high risk (n=32) disease. They treated patients with the Cyberknife platform to deliver between 18 and 21 Gy in three fractions in addition to 45 Gy in 25 fractions EBRT. With a median follow up of 33 months, BFFS was 89.5% and 77.7% for the intermediate and high risk patients respectively. A 5 mm expansion from the prostate to the Planned Treatment Volume (PTV) was used except posteriorly, where the margin was 3mm. There was 7% Grade 2 acute genitourinary (GU) and gastrointestinal (GI) toxicity, with late Grade 2 estimates at three years of 5.5% (GU) and 8.2% (GI). Three other series using Cyberknife to mimic HDR were reported between 2008 and 2012 (6, 7, 9). These studies used margins of 0-2 mm posteriorly and 3-5 mm in other directions and reported low rates of Grade 2 and Grade 3 toxicity. Two of these reports specifically attempted to reproduce the heterogeneity of HDR with large areas of the PTV receiving >125% (40% to 45%) and >150% (5% to 10%) of the prescribed dose. Miralbell et al. (10) reported a Linac based IMRT boost in 50 patients in 2010. This series used an endorectal balloon but no image guidance, which may be the cause of their unacceptably high five year estimates of late GI Grade 2 toxicity of 26%. Primary objective: The primary study goal is to assess the acute toxicity of Stereotactic Body Radiotherapy (SBRT) boost with three increasing dose levels. Secondary objectives: Nadir PSA at three months and over duration of follow-up Three year and five year Freedom From Biochemical Failure (FFBF) (Nadir + 2.0) Planning feasibility (Minor and Major planning violations) Late Gastrointestinal and Genitourinary Toxicity (modified Radiation Therapy Oncology Group (RTOG) scale) Patient reported QOL (EPIC-SF-12) Hypothesis: It is safe to dose escalate prostate cancer treatment with a stereotactic boost of up to 30Gy in two fractions to the dominant nodule combined with external beam radiotherapy of 46Gy in 23 fractions with < 15% Grade 2 acute morbidity and < 5% Grade 3 acute morbidity.

Inclusion Criterias

ECOG performance status 0-2
International Prostate Symptom Score (I-PSS) score <15
Histologically proven prostate adenocarcinoma
...
ECOG performance status 0-2
International Prostate Symptom Score (I-PSS) score <15
Histologically proven prostate adenocarcinoma
No contraindication to MRI (pacemaker, severe claustrophobia)
PSA obtained within three months prior to enrollment.
Ability to understand and the willingness to sign a written informed consent document.
Patient must be able to have fiducial markers placed in the prostate (if on anticoagulants, must be cleared by LMO or cardiologist).

Exclusion Criterias

Previous pelvic radiotherapy
Prior total prostatectomy
Unwilling or unable to give informed consent
...
Previous pelvic radiotherapy
Prior total prostatectomy
Unwilling or unable to give informed consent
Unwilling or unable to complete quality of life questionnaires.

Locations

St Leonards, New South Wales, 2065
St Leonards, New South Wales, 2065

Tracking Information

NCT #
NCT02004223
Collaborators
Not Provided
Investigators
  • Principal Investigator: Thomas N Eade, MBBS Royal North Shore Hospital
  • Thomas N Eade, MBBS Royal North Shore Hospital