Phase 1 Study of MRI Targeted Focal Laser Thermal Therapy of Biopsy Confirmed Prostate Cancer
This is a single center, single arm, open-label Phase I study to establish the safety of
interstitial laser thermal therapy (ILTT) in patients with a single site of low grade
(Gleason <7) prostate cancer who have not yet received treatment for their cancer. No
control group will be utilized and all patients will receive laser thermal therapy. The
patient will undergo multimode MRI to determine if a single site of prostate cancer can be
localized by this technique and to localize the tumor in 3 dimensions within the prostate.
A multicore (12 + cores) mapping transrectal ultrasound guided biopsy of the prostate would
then confirm that no other sites of cancer exist.
Each patient will complete quality of life and performance questionnaires. ILLT will be
performed under general anesthetic in a procedure similar to brachytherapy, using
transrectal ultrasound to guide insertion of the laser and monitoring probes into the sector
containing the cancer as visualized by the MR scan. Following the procedure, patients will
be assessed for clinical signs of urinary, rectal, and erectile complications and will
complete validated self-assessment tools on these functions. MRI at 7 days and MRI and
biopsy at 6 months will be used to assess the extent of tissue effect and presence of cancer
due to ILTT. Patients will remain on standard Watchful Waiting surveillance for any further
sign of disease progression. ILLT will not restrict any future treatment of prostate cancer.
To minimize the treatment risk, participants in the trial will be staged according to
location of the disease in the prostate. The first 3 participants recruited to the trial
will have targeted loci well separated from the urethra, erectile nerves and the rectum, and
so treatment in this region poses minimal risk of injury to these vital structures. Lesions
sizes measured in this initial stage will be used in planning fiber placement in the three
remaining stages, in which fiber placement is closer to critical structures such as the
urethra (Stage 2), erectile nerves (Stage 3) and rectum (Stage 4).
Allocation: Non-Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment
Clinical assessment of: urinary, rectal, erectile function
1 week, 1 month, 3 months, 6 months post procedure
John Trachtenberg, M.D.
University Health Network, Toronto
Canada: Health Canada