Stereotactic Body Radiation Therapy With Boost Using Urethral-Sparing Intensity-Modulated Radiation Therapy Planning in Treating Patients With Prostate Cancer

PRIMARY OBJECTIVES:

I. To evaluate the incidence of genitourinary (GU) and gastrointestinal (GI) acute and late
toxicity for patients treated with prostate stereotactic body radiotherapy (SBRT) with
simultaneous integrative boost, urethral ring sparing, and enhanced prostate localization
(magnetic resonance imaging [MRI\-computed tomography [CT] fusion).

II. To also evaluate the incidence of GU and GI acute and late toxicity for patients treated
with prostate stereotactic body radiotherapy (SBRT) with a more conventional and uniformly
delivered dose of 7.25 Gy/fraction to the prostate.

III. Disease-free survival: disease-free failure events include local progression, distant
progression, biochemical failure as defined by the Radiation Therapy Oncology Group (RTOG)
Phoenix definition, and death from any cause.

SECONDARY OBJECTIVES:

I. Evaluate patient quality of life (QOL) using the Expanded Prostate Cancer Index Composite
26 (EPIC-26) for evaluation of the QOL for up to 3 years after the completion of SBRT.

OUTLINE: Patients are assigned to 1 of 2 treatment arms. Patients unable to undergo MRI,
whose MRI proves technically inadequate for delineating needed anatomic structures, or who
decline to enroll on Arm A are assigned to Arm B.

ARM A: Patients undergo 5 fractions of moderate dose SBRT with simultaneous integrated boost
(SIB) every other day for 10 days following urethral-sparing IMRT planning.

ARM B: Patients undergo 5 fractions of uniform dose SBRT every other day for 10 days
following undergo urethral-sparing IMRT planning.

After completion of study treatment, patients are followed up at 4-6 weeks, at 4, 8, and 12
months, every 4 months for 1 year, every 6 months for 3 years, and then every 12 months
thereafter.

Inclusion Criteria:

- Histologically confirmed diagnosis of adenocarcinoma of the prostate and most recent
biopsy within 180 days of study enrollment

- History/physical examination with digital rectal examination of the prostate within 90
days prior to study enrollment

- Gleason score =< 7, no tertiary pattern >= 5

- Clinical stage =< T2b (American Joint Committee on Cancer [AJCC] 7th Edition Staging
Manual) and no radiographic evidence of T3 or T4 disease

- Clinical stage N0, M0

- Most recent prostate specific antigen (PSA) within 60 days of enrollment

- Maximum PSA =< 20 ng/ml (not within 20 days after biopsy)

- Eastern Cooperative Oncology Group (ECOG) performance status 0-1

- American Urological Association (AUA) =< 18 with or without medical management

- Up to a total of year of androgen deprivation allowed.

- Patient signs study specific informed consent prior to study enrollment

- Confirmation that insurance will cover SBRT through normal hospital authorization
process

Exclusion Criteria:

- FOR ARM A: Inability to obtain a planning MRI or a planning MRI of sufficient quality
to allow identification of the peripheral zone and urethra, or inability to adequately
fuse the MRI to the planning CT scan

- FOR BOTH ARM A AND ARM B:

- Prior or concurrent invasive malignancy (except non-melanomatous skin cancer) or
lymphomatous/hematogenous malignancy unless continually disease free for a minimum of
5 years; (for example, carcinoma in situ of the bladder or oral cavity is permissible)

- Prosthetic implants in the pelvic region that the investigator feels will impede
treatment, planning, or delivery (e.g., an artificial hip)

- =< 3 months from a transurethral resection of the prostate (TURP) procedure

- Significant urinary obstruction (i.e. AUA symptom score > 18)

- Previous pelvic irradiation, prostate brachytherapy

- Previous radical surgery (prostatectomy) or cryosurgery for prostate cancer

- Severe, active comorbidity, defined as follows:

- Acute bacterial or fungal infection requiring intravenous antibiotics at the time
of registration

- Crohn's disease or ulcerative colitis

- Scleroderma