Faculty Bibliography

PURPOSE/OBJECTIVE:We aim to evaluate prostate-specific antigen (PSA) trends in post-primary focal cryotherapy (PFC) patients. MATERIALS AND METHODS/METHODS:This was an institutional review board-approved retrospective study of PFC patients from 2010 to 2015. Patients with at least one post-PFC PSA were included in the study. Biochemical recurrence (BCR) was determined using the Phoenix criteria. PSA bounce was also assessed. We analyzed rates of change of PSA over time of post-PFC between BCR and no BCR groups. PSA-derived variables were analyzed as potential predictors of BCR. RESULTS:A total of 104 PFC patients were included in our analysis. Median (range) age and follow-up time were 66 (48-82) years and 19 (6.3-38.6) months, respectively. Four (3.8%) patients experienced PSA bounce. The median percent drop in first post-PFC PSA of 80.0% was not associated with BCR (p = 0.256) and may indicate elimination of the index lesion. The rate of increase of PSA in BCR patients was significantly higher compared to patients who did not recur (median PSA velocity (PSAV): 0.15 vs 0.04 ng/ml/month, p = 0.001). Similar to PSAV (HR 9.570, 95% CI 3.725-24.592, p < 0.0001), PSA nadir ≥ 2 ng/ml [HR (hazard ratio) 1.251, 95% CI 1.100-1.422, p = 0.001] was independently associated with BCR. CONCLUSION/CONCLUSIONS:A significant drop in post-PFC PSA may indicate elimination of the index lesion. Patients who are likely to recur biochemically have a significantly higher PSAV compared to those who do not recur. Nadir PSA of less than 2 ng/ml may be considered the new normal PSA in focal cryotherapy (hemiablation) follow-up.

There is a pressing need for further advancement in tissue engineering of functional organs with a view to providing a more clinically relevant model for drug development and reduce the dependence on organ donation. Polymer-based scaffolds, such as polycaprolactone (PCL), have been highlighted as a potential avenue for tissue engineered kidneys, but there is little investigation down this stream. Focus within kidney tissue engineering has been on two-dimensional cell culture and decellularised tissue. Electrospun polymer scaffolds can be created with a variety of fibre diameters and have shown a great potential in many areas. The variation in morphology of tissue engineering scaffold has been shown to effect the way cells behave and integrate. In this study we examined the cellular response to scaffold architecture of novel electrospun scaffold for kidney tissue engineering. Fibre diameters of 1.10 ± 0.16 μm and 4.49 ± 0.47 μm were used with three distinct scaffold architectures. Traditional random fibres were spun onto a mandrel rotating at 250 rpm, aligned at 1800 rpm with novel cryogenic fibres spun onto a mandrel loaded with dry ice rotating at 250 rpm. Human kidney epithelial cells were grown for 1 and 2 weeks. Fibre morphology had no effect of cell viability in scaffolds with a large fibre diameter but significant differences were seen in smaller fibres. Fibre diameter had a significant effect in aligned and cryogenic scaffold. Imaging detailed the differences in cell attachment due to scaffold differences. These results show that architecture of the scaffold has a profound effect on kidney cells; whether that is effects of fibre diameter on the cell attachment and viability or the effect of fibre arrangement on the distribution of cells and their alignment with fibres. Results demonstrate that PCL scaffolds have the capability to maintain kidney cells life and should be investigated further as a potential scaffold in kidney tissue engineering.

INTRODUCTION:Salvage treatment options for recurrent unilateral prostate cancer (PCa) after primary radiation are limited and associated with severe complications and poor quality of life measures. Salvage focal cryotherapy (SFC) has shown success in biochemical recurrence (BCR) free survival. We aim to determine if SFC can delay use of androgen deprivation therapy (ADT) in recurrent PCa with low morbidity. METHODS:A retrospective review of patients who underwent SFC at our institution from 2007 to 2015 was performed. Patients with <2 follow-up prostate-specific antigen (PSA) values, metastatic disease, and a history of radical prostatectomy were excluded. Age at treatment, prior treatment history, PSA nadir, complications, BCR status (nadir +2 ng/ml), and follow-up data were obtained/analysed. ADT was commenced if patient experienced BCR and had a PSA doubling time <6 months or positive confirmatory biopsy or positive imaging. Cox regression and survival analysis were used to assess confounding and time to BCR respectively. RESULTS:A total of 65 patients were included and followed for a median of 26.6 (8.0-99.0) months. Thirty-one (47.7%) patients did not experience BCR. An even higher number of patients (52/65, 80.0%) are yet to receive ADT. Of those who experienced BCR [median time to BCR, 17.1 [interquartile range (IQR):11.4-23.3] months], 22/34 (64.7%) are currently carefully monitored without ADT. Survival analysis showed a biochemical recurrence-free survival of 48.1 at 1- and 3-year follow up. No patient died/experienced major complications. CONCLUSIONS:SFC may be used to delay the use of ADT. Further assessment of our findings with high-powered studies and longer follow-up is required.

INTRODUCTION/BACKGROUND:We aimed to report on multiparametric MRI (mpMRI) characteristics of post-primary focal cryosurgery (PFC) patients suspected of biochemical recurrence (BCR) by the Phoenix criteria. METHODS:We retrospectively reviewed all patients at our institution who had undergone PFC. Prostate-specific antigen nadir was determined using 2 or more post-PFC values. Suspicion of BCR was determined using the Phoenix criteria (nadir + 2 ng/ml). At the discretion of the physician, pre-and post-PFC 3-T mpMRIs were obtained and in a few cases biopsies were performed. RESULTS:Ninety (58.4%) of 154 consecutive patients who underwent PFC were included in our analysis and had a median (range) age and prostate volume of 66.5 (48-82) years and 40.5 (16-175) ml, respectively. Of those suspected of BCR (37/90, 41.1%), with a median time to BCR of 19.9 (7.0-38.5) months, 27 patients (73.0%) underwent a post-PFC mpMRI. Twenty-two (81.5%) of these mpMRIs were found with 24 suspicious lesions. A considerable number (9/24, 37.5%) of these lesions were located in the central gland of the prostate. Seven of 24 lesions exhibited adverse mpMRI characteristic; 4 (16.7%) had capsular contact, 2 (8.2%) showed frank extracapsular extension, and 1 (4.2%) showed seminal vesicle invasion. Five (45.5%) of 11 patients with positive post-PFC mpMRIs were positive on biopsy (4/5, 80% were clinically significant prostate cancer). CONCLUSION/CONCLUSIONS:Post-PFC mpMRI, at Phoenix suspicion of BCR, may help identify a significant number of patients failing post-PFC.

BACKGROUND:The Phoenix definition (PD) and Stuttgart definition (SD) designed to determine biochemical recurrence (BCR) in patients with postradiotherapy and high-intensity focused ultrasound organ-confined prostate cancer are being applied to follow patients after cryosurgery. We sought to identify predictors of BCR using the PD and SD criteria in patients who underwent primary focal cryosurgery (PFC). MATERIALS AND METHODS:We performed a retrospective review of patients who underwent PFC (hemiablation) at 2 referral centers from 2000 to 2014. Patients were followed up with serial prostate-specific antigen (PSA). PSA levels, pre- and post-PFC biopsy, Gleason scores, number of positive cores, and BCR (PD = [PSA nadir+2ng/ml]; SD = [PSA nadir+1.2ng/ml]) were recorded. Patients who experienced BCR were biopsied, monitored carefully or treated at the discretion of the treating urologist. Cox regression and survival analyses were performed to assess time to BCR using PD and SD. RESULTS:A total of 163 patients were included with a median follow-up of 36.6 (interquartile range: 18.9-56.4) months. In all, 64 (39.5%) and 98 (60.5%) experienced BCR based on PD and SD, respectively. On multivariable Cox regression, the number of positive pre-PFC biopsy cores was an independent predictor of both PD (hazard ratio [HR] = 1.4, P = 0.001) and SD (HR = 1.3, P = 0.006) BCRs. Post-PFC PSA nadir was an independent predictor of BCR using the PD (HR = 2.2, P = 0.024) but not SD (HR = 1.4, P = 0.181). Survival analysis demonstrated a 3-year BCR-free survival rate of 56% and 36% for PD and SD, respectively. Of those biopsied after BCR, 14/26 (53.8%) using the PD and 18/35 (51.4%) using the SD were found to have residual/recurrent cancer. Of those with prostate cancer on post-PFC biopsy, 57.1% of those with BCR by the PD and 66.7% of those with BCR by the SD were found to have a Gleason score ≥7. CONCLUSION:Both the PD and the SD may be used to determine BCR in post-PFC patients. However, the ideal definition of BCR after PFC remains to be elucidated.

The incidence of the small renal mass continues to increase owing to the aging population and the ubiquity imaging. Most of these tumors are stage I tumors. Management strategies include surveillance, ablation, and extirpation. There is a wide body of literature favoring nephron-sparing approaches. Although nephron-sparing surgery may yield decreased long-term morbidity, it is not without its drawbacks, including a higher rate of complications. Urologists must be attuned to the complications of surgery and develop strategies to minimize risk. This article reviews expected complications of surgery on renal masses and risk stratification schema.