MRI-Mapped Dose-Escalated Salvage Radiotherapy Post-Prostatectomy: The MAPS Trial

Prostate-Specific Antigen (PSA) response rate is defined as the percentage of study patients with PSA less than 0.1 ng/mL at 21 months after completion of study treatment.

Incidence of treatment-emergent toxicity in study participants. Toxicity is defined as adverse events (AEs), serious adverse events (SAEs) and dose-limiting toxicities (DLTs)Acute toxicity is defined as toxicity occurring during treatment and within three months of completing treatment. Late toxicity is toxicity occurring more than three months after treatment completion. Toxicity will be assessed using the NCI Common Terminology Criteria for Adverse Events (CTCAE) version 4.0

Health-related Quality of Life (HRQOL) will be measured using the Expanded Prostate Cancer Index Composite and Medical Outcomes Study SF-12 (EPIC SF-12) to evaluate patient function and satisfaction after prostate cancer treatment. Response options for each item form a Likert scale, and multi-item scale scores are transformed linearly to a 0-100 scale, with higher scores representing better HRQOL.

Health-related quality of life (HRQOL) will be measured using the scores on the Modified 18-item Memorial Anxiety Scale for Prostate Cancer (MAX-PC) from pre-treatment to post-treatment. The scale consists of 18 items (e.g. "I thought about prostate cancer even though I didn't mean to.") scored on a scale from 0 ("not at all") to 3 ("often"). Total scores range from 0 to 54, with higher scores indicating higher levels of anxiety.

Health-related quality of life (HRQOL) will be measured using the International Prostate Symptom Score (IPSS) to evaluate patient urinary function and quality of life. There are 7 questions related to urinary function. Responses are on a scale from 0 ("not at all") to 5 ("almost always"), with higher scores indicating higher levels of urinary dysfunction. There is 1 quality of life question related to urinary symptoms. Responses are on a scale from 0 ("delighted") to 6 ("terrible").

The cumulative incidence of biochemical or clinical failure allowing for competing risk as needed. Clinical failure is defined as at least a 25% increase in the size of the tumor relative to the smallest volume recorded, or new extension of tumor beyond the capsule, or re-extension of tumor beyond the capsule after initial regression, or urinary obstructive symptoms with carcinoma found at transurethral resection of the prostate (TURP). Biochemical failure is defined as PSA ≥ nadir + 2 ng/mL.

Rate of failure-free survival in study participants. Failure-free survival is defined as the elapsed time from start of radiotherapy to first documented evidence of biochemical or clinical failure or death from any cause, whichever occurs first. In the absence of any event defining failure, follow-up time will be censored at the date of last documented failure-free status.

Rate of overall survival in study participants. Overall survival is defined as the elapsed time from start of radiotherapy to death from any cause. For surviving patients, follow-up will be censored at the date of last contact.

The distribution and degree of expression of tissue biomarkers by ultrasound-directed biopsies for patients who choose to undergo the optional biopsies. Quantification of the amount of the biomarker specific immunohistochemical staining in the area of tumor.

To determine the incidence and relationship of circulating DNA and tumor cells to tissue biomarkers and initial complete biochemical response.