2 Gy of EBRT. Biochemical control was observed in 88% of patients with a median followup of 30 months (19). Burri et al. have reported the outcomes of 37 patients with a median followup of 87 months who underwent low-dose-rate salvage brachytherapy.

At 5-year followup, 65% of patients were found to have achieved biochemical Veliparib manufacturer freedom from failure (Phoenix definition), and 57% remained free of biochemical failure at 10 years. Grade 3 or 4 toxicity was noted in 11% of patients, consisting of transurethral resection of the prostate (TURP) in 2 patients, hematuria requiring fulguration in one patient, and one case of prostatorectal fistula (20). Several aspects unique to HDR brachytherapy make it ideally suited for use as a salvage procedure. • Brachytherapy delivers high-dose radiation directly to the target tissue. In the case of EBRT, radiation must pass through skin, muscle, bone, bowel, and other soft tissues to reach the prostate. Thus, in the setting of previously irradiated patients, HDR brachytherapy can deliver radiation without repeating significant exposure to these surrounding tissues. In addition, a patient-based dosimetric comparison between stereotactic body radiotherapy and HDR brachytherapy found that EBRT was not able

to achieve either the high doses to the prostate or the dose-sparing effect on normal tissues that HDR brachytherapy Smad signaling is able to achieve (21), underscoring the advantages of HDR over external beam techniques. The results of the University of California San Francisco (UCSF)

salvage HDR experience have been recently updated (7). In this retrospective analysis, 52 consecutive patients received 36 Gy in six fractions, given in two insertions, 1 week apart. With a median followup of 60 months, 51% of patients were found to be biochemically free of relapse at 2 years, and only two patients developed Grade 3 or higher GU toxicity using CTAE criteria. An initial report published Leukotriene-A4 hydrolase in 2007 reported 14% Grade 3 complications in 21 patients with a median followup of 19 months (22), suggesting that, with further time, Grade 3 complications tend to improve. The results of the USCF experience as well as the current report have used dose-fractionation schedules with similar biologic effective doses (170–180 Gy, assuming an α/β of 1.5 Gy) with acceptable toxicity and tumor control, suggesting that either 36 Gy in six fractions with two insertions, or 32 Gy in four fractions in a single insertion, would be appropriate fractionation schedules to consider. However, the optimal dose-fractionation schedule for salvage HDR brachytherapy has yet to be elucidated. As illustrated in Table 3, the outcomes of the present study compare favorably with results in the literature. HDR brachytherapy is an excellent treatment for salvage because it provides the high doses for hypofractionation while maintaining low doses to the urethra, bladder, and rectum.