Hypofractionated Stereotactic Body Radiation Therapy for Patients With Prostate Cancer That Was Removed by Surgery

PRIMARY OBJECTIVES:

I. To determine maximum tolerated dose-per-fraction for SBRT to the prostate fossa following
prostatectomy based on acute toxicity (< 90 days).

SECONDARY OBJECTIVES:

I. To describe the acute (< 90 days) toxicities and adverse events associated with
hypofractionated SBRT when administered to the prostate bed in the post-prostatectomy
setting.

II. To describe the late (> 90 days from treatment) toxicities and adverse events associated
with hypofractionated SBRT when administered to the prostate bed in the post-prostatectomy
setting.

TERTIARY OBJECTIVES:

I. To describe the patient-reported toxicity/quality of life (QOL) following hypofractionated
SBRT treatment.

OUTLINE: This is a dose-escalation study.

Patients undergo 5, 10, or 15 fractions of hypofractionated SBRT daily over 1-3 weeks.

After completion of study treatment, patients are followed up at 2, 6, and 13 weeks and then
at 6, 9, 12, 18, 24, 30 and 36 months.

Inclusion Criteria:

- Adenocarcinoma of the prostate treated primarily with radical prostatectomy

- Any type of radical prostatectomy is permitted including retropubic, perineal,
laparoscopic or robotically assisted; there is no time limit for the date of
radical prostatectomy

- One of the following pathologic classifications

- T3N0 disease with or without a positive surgical margin or

- T2N0 disease with or without a positive surgical margin

- Those with T2N0 disease and a negative margin must have a detectable
prostate-specific antigen (PSA) following radical prostatectomy or

- Must have had an undetectable PSA after prostatectomy and has since had a
rise in post-operative PSA to 0.2 ng/mL or greater

- Zubrod performance status of 0 -1

- No distant metastases, based on the following workup within 60 days prior to
registration

- Magnetic resonance imaging (MRI) of the pelvis

- Bone scan or sodium fluoride positron emission tomography (PET), that if
suspicious has MRI or plain X-rays to rule out bone metastasis

- Patients can be on androgen deprivation therapy

- Ability to understand and willingness to sign a study-specific informed consent prior
to study entry

Exclusion Criteria:

- N1 patients are ineligible, as are those with lymph node (LN) enlargement > 1.5 cm by
computed tomography (CT) or MRI of the pelvis, unless the LN is biopsy proven to be
negative

- Gross residual disease in the prostate fossa appreciated wither on digital rectal
examination (DRE) or on imaging, unless biopsy proven not to contain cancer

- Patients who were exposed to neoadjuvant chemotherapy or chemotherapy after
prostatectomy

- Prior radiation of any kind to the prostate gland or pelvis

- Prior brachytherapy is not allowed

- History of inflammatory colitis or other active severe comorbidities

- Patients who are on immunosuppressant medication