Faculty Bibliography

PURPOSE/OBJECTIVE:To examine the time dependent rates of urinary continence (UC) following open retropubic radical prostatectomy (ORRP). MATERIALS AND METHODS/METHODS:1,995 men undergoing RP were enrolled in a prospective, longitudinal outcomes study. The University of California, Los Angeles-Prostate Cancer Index Urinary Function Index (UCLA-PCI-UFS) was administered at baseline, 3, 6, 12, 24, 96, 120, and 180 months post-ORRP. Urinary continence was defined by <1 pad in 24 hours. Two multiple regression models were used to evaluate the association of time since ORRP with UCLA-PCI-UFI score and UC. RESULTS:The decrease in UC rates between baseline and 15 years (99.6% vs. 87.2%, p<0.001) and 2 and 15 years (95.3% vs. 87.2%, p=0.021) were statistically significant. UC rates were consistently higher in the younger group at all time points. CONCLUSION/CONCLUSIONS:A significant decrease in UC rates was observed between baseline to 2 years and 2 to 15 years for the entire cohort. UC rates for age-matched men in the general population followed longitudinally for 15 years are comparable to our study population suggesting that while ORRP causes primarily sphincteric urinary incontinence, it may be protective for subsequent BPH mediated urinary incontinence.

Tobacco smoke (TS) contains numerous cancer-causing agents, with polycyclic aromatic hydrocarbons (PAHs) and nitrosamines being most frequently cited as the major TS human cancer agents. Many lines of evidence seriously question this conclusion. To resolve this issue, we determined DNA adducts induced by the three major TS carcinogens: benzo(a)pyrene (BP), 4-(methylnitrosamine)-1-(3-pyridyl)-1-butanoe (NNK), and aldehydes in humans and mice. In mice, TS induces abundant aldehyde-induced γ-hydroxy-propano-deoxyguanosine (γ-OH-PdG) and α-methyl-γ-OH-PdG adducts in the lung and bladder, but not in the heart and liver. TS does not induce the BP- and NNK-DNA adducts in lung, heart, liver, and bladder. TS also reduces DNA repair activity and the abundance of repair proteins, XPC and OGG1/2, in lung tissues. These TS effects were greatly reduced by diet with polyphenols. We found that γ-OH-PdG and α-methyl-γ-OH-PdG are the major adducts formed in tobacco smokers' buccal cells as well as the normal lung tissues of tobacco-smoking lung cancer patients, but not in lung tissues of nonsmokers. However, the levels of BP- and NNK-DNA adducts are the same in lung tissues of smokers and nonsmokers. We found that while BP and NNK can induce BPDE-dG and O⁶-methyl-dG adducts in human lung and bladder epithelial cells, these inductions can be inhibited by acrolein. Acrolein also can reduce DNA repair activity and repair proteins. We propose a TS carcinogenesis paradigm. Aldehydes are major TS carcinogens exerting dominant effect: Aldehydes induce mutagenic PdG adducts, impair DNA repair functions, and inhibit many procarcinogens in TS from becoming DNA-damaging agents.

BACKGROUND:There is no consensus regarding how to assess oncological control following focal ablation of prostate cancer. OBJECTIVE:To assess quality of life and in-field recurrence following focal laser ablation (FLA). DESIGN, SETTING, AND PARTICIPANTS/METHODS:Of 34 men participating in a prospective outcomes study following FLA, 32 underwent prostate-specific antigen (PSA) testing and magnetic resonance imaging (MRI) at 6 mo and 2 yr. All underwent assessment of urinary and sexual function at 1 yr. INTERVENTION/METHODS:FLA and MRI-targeted biopsy of the ablation zone. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS/UNASSIGNED:The American Urological Association Symptom Score and the Sexual Health Inventory for Men at baseline and 12 mo were compared using a two-sided Wilcoxon signed-rank test with a significance level of p=0.05. The percentage of positive and negative in-field biopsies was calculated for suspicious and nonsuspicious post-ablation MRI scans. RESULTS AND LIMITATIONS/CONCLUSIONS:FLA was associated with no adverse impact on urinary or sexual function. For men with suspicious MRI (MRI+) findings, in-field disease recurrence of intermediate and low risk disease was detected in 75% and 25% of cases, respectively. For men with nonsuspicious MRI (MRI-) findings, in-field disease recurrence of intermediate- and low-risk disease was detected in 22.4% and 50% of cases, respectively. The change in PSA from baseline did not discriminate cases with MRI- findings with and without cancer at 2 yr. CONCLUSIONS:MRI reliably identifies in-field recurrence of only intermediate-risk prostate cancer at 2 yr after FLA. A biopsy of the ablation zone must be performed for MRI+ findings. The decision to perform an ablation-zone biopsy for men with MRI- scans should be influenced by whether detection of low-risk disease would influence management. PATIENT SUMMARY/UNASSIGNED:Our study provides compelling evidence that men should undergo interval magnetic resonance imaging to assess the probability of intermediate-risk disease in the ablation zone following focal laser ablation of localized prostate cancer.

Background/UNASSIGNED:Active surveillance (AS) is the most rapidly expanding management option for favorable-risk prostate cancer (PCa). Early studies suggested substantial decrements in utility (quality of life weights) from disease-related anxiety. Our objective was to determine utilities for contemporary AS patients using different instruments. Methods/UNASSIGNED:We performed a systematic review of PubMed, PMC and OVID for utility measurements in modern AS patients. We then examined utilities among 37 men on AS participating in focus groups between 2015-2016 using the generic EurQol five dimensions questionnaire (EQ-5D-3L) and Patient Oriented Prostate Utility Scale (PORPUS), a PCa-specific instrument. Results/UNASSIGNED:The systematic review found previous studies with utilities for PCa treatment and historical watchful waiting populations, but none specifically in contemporary AS. In our AS population, the mean EQ-5D-3L score was 0.90±0.16 (median, 1.00; range, 0.21-1.00) and PORPUS was 0.98±0.03 (median, 0.99; range, 0.84-1.00). The Spearman correlation between the EQ-5D-3L and PORPUS was 0.87 (P<0.0001), and 38% of patients had a difference >0.1 between instruments. Conclusions/UNASSIGNED:Most contemporary AS patients had high utility scores suggesting that they perceive themselves in good health without a major decrement in quality of life from the disease. However, some patients had substantial differences in utility measured with generic versus disease-specific instruments. Further study is warranted into the optimal instrument for utility assessment in contemporary AS patients.

E-cigarette smoke delivers stimulant nicotine as aerosol without tobacco or the burning process. It contains neither carcinogenic incomplete combustion byproducts nor tobacco nitrosamines, the nicotine nitrosation products. E-cigarettes are promoted as safe and have gained significant popularity. In this study, instead of detecting nitrosamines, we directly measured DNA damage induced by nitrosamines in different organs of E-cigarette smoke-exposed mice. We found mutagenic O6-methyldeoxyguanosines and γ-hydroxy-1,N2 -propano-deoxyguanosines in the lung, bladder, and heart. DNA-repair activity and repair proteins XPC and OGG1/2 are significantly reduced in the lung. We found that nicotine and its metabolite, nicotine-derived nitrosamine ketone, can induce the same effects and enhance mutational susceptibility and tumorigenic transformation of cultured human bronchial epithelial and urothelial cells. These results indicate that nicotine nitrosation occurs in vivo in mice and that E-cigarette smoke is carcinogenic to the murine lung and bladder and harmful to the murine heart. It is therefore possible that E-cigarette smoke may contribute to lung and bladder cancer, as well as heart disease, in humans.

OBJECTIVE:To understand the informational needs during active surveillance (AS) for prostate cancer from the perspectives of patients and providers. METHODS:We conducted seven focus groups with 37 AS patients in two urban clinical settings, and 24 semi-structured interviews with a national sample of providers. Transcripts were analyzed using applied thematic analysis, and themes were organized using descriptive matrix analyses. RESULTS:We identified six themes related to informational needs during AS: 1) more information on prostate cancer (biopsy features, prognosis), 2) more information on active surveillance (difference from watchful waiting, testing protocol), 3) more information on alternative management options (complementary medicine, lifestyle modification), 4) greater variety of resources (multiple formats, targeting different audiences), 5) more social support and interaction, and 6) verified integrity of information (trusted, multidisciplinary and secure). CONCLUSIONS:Patients and providers described numerous drawbacks to existing prostate cancer resources and a variety of unmet needs including information on prognosis, AS testing protocols, and lifestyle modification. They also expressed a need for different types of resources, including interaction and unbiased information. PRACTICAL IMPLICATIONS/CONCLUSIONS:These results are useful to inform the design of future resources for men undergoing AS.

OBJECTIVE: To develop nomograms that predict the probability of overall PCa and clinically significant PCa (Gleason >/=7) on MRI targeted, and combined MRI-targeted and systematic, prostate biopsy. MATERIALS AND METHODS: From June 2012 to August 2014, MR-US fusion targeted prostate biopsy was performed on 464 men with suspicious regions identified on pre-biopsy 3T MRI along with systematic 12 core biopsy. Logistic regression modeling was used to evaluate predictors of overall and clinically significant PCa, and corresponding nomograms were generated for men who were not previously biopsied or had one or more prior negative biopsies. Models were created with 70% of a randomly selected training sample and bias-corrected using bootstrap resampling. The models were then validated with the remaining 30% testing sample pool. RESULTS: A total of 459 patients were included for analysis (median age 66 years, PSA 5.2 ng/ml, prostate volume 49 cc). Independent predictors of PCa on targeted and systematic prostate biopsy were PSA density, age, and MRI suspicion score. PCa probability nomograms were generated for each cohort using the predictors. Bias-corrected areas under the receiver-operating characteristic curves for overall and clinically significant PCa detection were 0.82 (0.78) and 0.91 (0.84) for men without prior biopsy and 0.76 (0.65) and 0.86 (0.87) for men with a prior negative biopsy in the training (testing) samples. CONCLUSION: PSA density, age, and MRI suspicion score predict prostate cancer on combined MRI-targeted and systematic biopsy. Our generated nomograms demonstrate high diagnostic accuracy and may further aid in the decision to perform biopsy in men with clinical suspicion of PCa.

OBJECTIVE: To provide insights into the role of mpMRI for predicting oncological control following two focal ablation (FA) templates for selective cases of prostate cancer (PCa). MATERIALS AND METHODS: 59 radical prostatectomies were performed between 2012 and 2016 on cases that fulfilled criteria for FA. The Gleason score (GS), extent of Gleason pattern (GP) 4, maximum linear cross sectional length (MLCSL) and location of tumor foci were recorded and related to scale on corresponding 3mm transverse slice prostate maps. Gleason pattern 4 extra-focal disease (GP4EFD) was defined as PCa with any GP 4 not detected by mpMRI and transrectal ultrasound systematic biopsy observed outside a specified ablation zone. The location of these GP4EFD relative to the MRI lesion (MRI-L) (contralateral or ipsilateral) was recorded and used to predict oncological control following a hypothetical margin and ipsilateral hemi-ablation templates. RESULTS: Overall, 15/59 (25.4%) of the prostate specimens had at least one GP4EFD. Of the total 20 GP4EFD, 7/20 (35%) were ipsilateral and 13/20 (65%) were contralateral to the MRI-L. Of the GP4EFD, 16/20 (80%), 2/20 (10%), and 2/20 (10%) were GS 3+4, GS 4+3, and GS 4+4, respectively. Of these GP4EFD, 10/20 (50%) exhibited a MLCSL < 5mm. Ablating only the MRI-L+10mm or performing a ipsilateral hemi-ablation would leave residual GP4 in 14/59 (23.7%) and 11/59 (18.6%) of cases, respectively. CONCLUSIONS: Since a significant proportion of candidates for FA based on mpMRI and systematic biopsy will have pre-existing GP4EFD outside ablation templates, active surveillance of the untreated prostate is mandatory.