Faculty Bibliography

Laser interstitial thermal therapy (LITT) has recently shown great promise as a treatment strategy for localized, focal, low-grade, organ-confined prostate cancer (CaP). Additionally, LITT is compatible with multi-parametric magnetic resonance imaging (MP-MRI) which in turn enables (1) high resolution, accurate localization of ablation zones on in vivo MP-MRI prior to LITT, and (2) real-time monitoring of temperature changes in vivo via MR thermometry during LITT. In spite of rapidly increasing interest in the use of LITT for treating low grade, focal CaP, very little is known about treatment-related changes following LITT. There is thus a clear need for studying post-LITT changes via MP-MRI and consequently to attempt to (1) quantitatively identify MP-MRI markers predictive of favorable treatment response and longer term patient outcome, and (2) identify which MP-MRI markers are most sensitive to post-LITT changes in the prostate. In this work, we present the first attempt at examining focal treatment-related changes on a per-voxel basis (high resolution) via quantitative evaluation of MR parameters pre- and post-LITT. A retrospective cohort of MP-MRI data comprising both pre- and post-LITT T2-weighted (T2w) and diffusion-weighted (DWI) acquisitions was considered, where DWI MRI yielded an Apparent Diffusion Co-efficient (ADC) map. A spatially constrained affine registration scheme was implemented to first bring T2w and ADC images into alignment within each of the pre- and post-LITT acquisitions, following which the pre- and post-LITT acquisitions were aligned. Pre- and post-LITT MR parameters (T2w intensity, ADC value) were then standardized to a uniform scale (to correct for intensity drift) and then quantified via the raw intensity values as well as via texture features derived from T2w MRI. In order to quantify imaging changes as a result of LITT, absolute differences were calculated between the normalized pre- and post-LITT MRI parameters. Quantitatively combining the ADC and T2w MRI parameters enabled construction of an integrated MP-MRI difference map that was highly indicative of changes specific to the LITT ablation zone. Preliminary quantitative comparison of the changes in different MR parameters indicated that T2w texture may be highly sensitive as well as specific in identifying changes within the ablation zone pre- and post-LITT. Visual evaluation of the differences in T2w texture features pre- and post-LITT also appeared to provide an indication of LITT-related effects such as edema. Our preliminary results thus indicate great potential for non-invasive MP-MRI imaging markers for determining focal treatment related changes, and hence long- and short-term patient outcome.

Many clinically localized prostate cancers that are diagnosed today are low risk, and prevention of disease-specific mortality may only be realized decades after treatment. Radical prostatectomy (RP) may adversely impact health-related quality of life (HRQOL) by causing both transient or permanent urinary incontinence and erectile dysfunction. In contrast, RP may also improve HRQOL via relief of lower urinary tract symptoms in men suffering from these symptoms prior to surgery. Because the average man treated for prostate cancer has a life expectancy of approximately 14 years, it is imperative to consider the long-term impact of RP on both survival and HRQOL in treatment decision making. This comprehensive literature review examines short-, intermediate-, and long-term HRQOL following RP. In addition, the long-term results of RP are compared with other treatment modalities for treating clinically localized prostate cancer.

IMPORTANCE: Soy consumption has been suggested to reduce risk or recurrence of prostate cancer, but this has not been tested in a randomized trial with prostate cancer as the end point. OBJECTIVE: To determine whether daily consumption of a soy protein isolate supplement for 2 years reduces the rate of biochemical recurrence of prostate cancer after radical prostatectomy or delays such recurrence. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind trial conducted from July 1997 to May 2010 at 7 US centers comparing daily consumption of a soy protein supplement vs placebo in 177 men at high risk of recurrence after radical prostatectomy for prostate cancer. Supplement intervention was started within 4 months after surgery and continued for up to 2 years, with prostate-specific antigen (PSA) measurements made at 2-month intervals in the first year and every 3 months thereafter. INTERVENTION: Participants were randomized to receive a daily serving of a beverage powder containing 20 g of protein in the form of either soy protein isolate (n=87) or, as placebo, calcium caseinate (n=90). MAIN OUTCOMES AND MEASURES: Biochemical recurrence rate of prostate cancer (defined as development of a PSA level of >/=0.07 ng/mL) over the first 2 years following randomization and time to recurrence. RESULTS: The trial was stopped early for lack of treatment effects at a planned interim analysis with 81 evaluable participants in the intervention group and 78 in the placebo group. Overall, 28.3% of participants developed biochemical recurrence within 2 years of entering the trial (close to the a priori predicted recurrence rate of 30%). Among these, 22 (27.2%) occurred in the intervention group and 23 (29.5%) in the placebo group. The resulting hazard ratio for active treatment was 0.96 (95% CI, 0.53-1.72; log-rank P = .89). Adherence was greater than 90% and there were no apparent adverse events related to supplementation. CONCLUSION AND RELEVANCE: Daily consumption of a beverage powder supplement containing soy protein isolate for 2 years following radical prostatectomy did not reduce biochemical recurrence of prostate cancer in men at high risk of PSA failure. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00765479.

OBJECTIVE: To elucidate the probability that Gleason 6 tumors diagnosed in the prostate-specific antigen (PSA) era treated with radical prostatectomy (RP) develop metastasis. METHODS: Between October 2000 and June 2012, 1781 men underwent open RP by a single surgeon. Biochemical recurrence (BCR) was defined as a serum PSA value >/=0.2 ng/mL, or 2 progressively rising PSA values >0.14 ng/mL. Significant BCR (sBCR) was defined as a BCR with a PSA doubling time (PSADT) <36 months. Insignificant BCR (iBCR) was defined as BCR with a PSADT >/=36 months. RESULTS: Eight hundred fifty-seven of men (48.1%) undergoing open RP had a pathologic diagnosis of Gleason 6. Twenty-three of 857 of these men (2.7%) developed BCR, 7 were designated as iBCR (mean PSADT 81 months, range 36 to 100), 16 were sBCR (mean PSADT 8 months, range 1.5-20 months). There was a 10-fold difference in PSADT between the sBCR and iBCR groups (P <.001). All men with sBCR underwent salvage radiation therapy (SRT) and all demonstrated a subsequent PSA decline to