Focal Salvage HDR Brachytherapy for Locally Recurrent Prostate Cancer in Patients Treated With Prior Radiotherapy

The goal of any radiation treatment plan is to achieve maximal disease response with minimal
toxicity. HDR brachytherapy offers a promising definitive treatment option in the setting of
Locally Recurrent Prostate Cancer after prior definitive radiation, based on the limited data
described above, with achievement of biochemical disease control in a large percentage of
patients with relatively low toxicity. With focal HDR brachytherapy, the investigators can
treat the isolated areas of disease, while avoiding normal prostate tissue, with the goal of
further improving toxicity rates. The investigators hypothesize that using single fraction,
focal HDR brachytherapy performed with one single implant for the treatment of LRPC is
feasible and without excess toxicity, and can be safely delivered. This should allow for
better patient convenience and cost and improved treatment dosimetry and planning, as it will
decrease the risk of catheter displacement between fractions, which will hopefully correlate
to less GU and non-GU acute toxicity. The primary objective is to determine the acute and
late GU and GI toxicity of single fraction focal HDR salvage brachytherapy (primary
endpoint).

Inclusion Criteria:

- Biopsy proven locally recurrent adenocarcinoma of the prostate after the completion of
definitive radiation therapy for initially diagnosed prostate cancer.

- Biopsy must be performed within 182 days of trial registration

- Biopsy should be a standard sextant biopsy AND either a targeted MR/ultrasound
guided biopsy or saturation biopsy or both.

- Initial cancer diagnosis that fits these specific criteria:

- Stages T1-T3a

- Nx or N0

- Mx or M0

- Eligible initial definitive radiotherapy modalities include:

- External beam radiotherapy, with photon or proton beam therapy

- Conventional or moderately hypofractionated radiotherapy

- Extremely hypofractionated external beam radiotherapy (Stereotactic body
radiation therapy)

- Definitive Brachytherapy:

- Low-dose rate

- High-dose rate

- Locally recurrent disease confined to the prostate +/- seminal vesicles and
immediately adjacent tissue, as evaluated by the following:

- History/Physical examination

- Radiographically node negative disease (N0), as defined by CT or MR of pelvis +/-
abdomen within 6 months of registration.

- No evidence of bone metastases (M0) on bone scan within 6 months of registration.

- Fluciclovine-PET is encouraged, but not required

- Patients receiving ADT are eligible as long as they meet the other eligibility
criteria. However, the duration of all ADT must be documented.

- Current ECOG Performance status Scale 0-2

- Current International Prostate Symptom Score (IPSS) < 20

- The patient must be medically suitable to receive general anesthesia.

- The patient must be able and willing to sign a study-specific written informed consent
form before study entry.

Exclusion Criteria:

- Preregistration GI or GU toxicity (for any reason) grade ≥ 3 as defined in CTCAE
version 4.03. That is, grade ≥ 3 GU or GI toxicity after first course of radiotherapy

- Patients receiving any other investigational agents.

- Uncontrolled inter-current illness including, but not limited to, ongoing or active
infection, severely symptomatic congestive heart failure, cardiac arrhythmia, recent
myocardial infarction in last 6 months, or psychiatric illness/social situations that
could limit compliance with study requirements.

- Patients who have received chemotherapy or immunotherapy within one month prior to
study enrollment, other than ADT