The impact of body mass index on treatment outcomes for patients with low-intermediate risk prostate cancer.

BACKGROUND: Little is known about the relationship between preoperative body mass index and need for adjuvant radiation therapy (RT) following radical prostatectomy. The goal of this study was to evaluate the utility of body mass index in predicting adverse clinical outcomes which require adjuvant RT among men with organ-confined prostate cancer (PCa). METHODS: We used a prospective cohort of 1,170 low-intermediate PCa risk men who underwent radical prostatectomy and evaluated the effect of body mass index on adverse pathologic features and freedom from biochemical failure (FFbF). Clinical and pathologic variables were compared across the body mass index groups using an analysis of variance model for continuous variables or χ(2) for categorical variables. Factors related to adverse pathologic features were examined using logistic regression models. Time to biochemical recurrence was compared across the groups using a log-rank survivorship analysis. Multivariable analysis predicting biochemical recurrence was conducted with a Cox proportional hazards model. RESULTS: Patients with elevated body mass index (defined as body mass index ≥25 kg/m(2)) had greater extraprostatic extension (p = 0.004), and positive surgical margins (p = 0.01). Elevated body mass index did not correlate with preoperative risk groupings (p = 0.94). However, when compared with non-obese patients (body mass index <30 kg/m(2)), obese patients (body mass index ≥30 kg/m(2)) were much more likely to have higher rate of adverse pathologic features (p = 0.006). In patients with low- and intermediate- risk disease, obesity was strongly associated with rate of pathologic upgrading of tumors (p = 0.01 and p = 0.02), respectively. After controlling for known preoperative risk factors, body mass index was independently associated with ≥2 adverse pathologic features (p = 0.002), an indicator for adjuvant RT as well as FFbF (p = 0.001). CONCLUSIONS: Body mass index of ≥30 kg/m(2) is independently associated with adverse pathologic features, which is an indicator for additional RT, particularly in patients with low-intermediate risk disease. Future studies may determine if this select group of patients may be best treated with definitive RT to reduce toxicity from additional RT following radical prostatectomy. We propose including body mass index in clinical decision-making for appropriate treatment recommendation for patients with low-intermediate risk PCa.

African American men with low-grade prostate cancer have increased disease recurrence after prostatectomy compared with Caucasian men.

PURPOSE: To explore whether disparities in outcomes exist between African American (AA) and Caucasian (CS) men with low-grade prostate cancer and similar cancer of the prostate risk assessment-postsurgery (CAPRA-S) features following prostatectomy (RP). METHODS: The overall cohort consisted of 1,265 men (234 AA and 1,031 CS) who met the National comprehensive cancer network criteria for low- to intermediate-risk prostate cancer and underwent RP between 1990 and 2012. We first evaluated whether clinical factors were associated with adverse pathologic outcomes and freedom from biochemical failure (FFbF) using the entire cohort. Next, we studied a subset of 705 men (112 AA and 593 CS) who had pathologic Gleason score≤6 (low-grade disease). Using this cohort, we determined whether race affected FFbF in men with RP-proven low-grade disease and similar CAPRA-S scores. RESULTS: With a median follow-up time of 27 months, the overall 7-year FFbF rate was 86% vs. 79% in CS and AA men, respectively (P = 0.035). There was no significant difference in one or more adverse pathologic features between CS vs. AA men (27% vs. 31%; P = 0.35) or CAPRA-S score (P = 0.28). In the subset analysis of patients with low-grade disease, AA race was associated with worse FFbF outcomes (P = 0.002). Furthermore, AA race was a significant predictor of FFbF in men with low-grade disease (hazard ratio = 2.01, 95% CI: 1.08-3.72; P = 0.029). CONCLUSIONS: AA race is a predictor of worse FFbF outcomes in men with low-grade disease after RP. These results suggest that a subset of AA men with low-grade disease may benefit from more aggressive treatment.

African-american race is a predictor of seminal vesicle invasion after radical prostatectomy.

INTRODUCTION: The purpose of the study was to determine whether racial differences exist in the pattern of local disease progression among men treated with radical prostatectomy (RP) for localized prostate cancer (PCa), which is currently unknown. In this study we evaluated the pattern of adverse pathologic features in an identical cohort of African-American (AA) and Caucasian (CS) men with PCa. PATIENTS AND METHODS: The overall cohort consisted of 1104 men (224 AA, and 880 CS) who underwent RP between 1990 and 2012. We compared preoperative factors and pathologic outcomes after RP across race groups. Multivariate analysis was used to identify factors predictive of adverse pathologic outcomes. The effect of race on adverse pathologic outcomes and biochemical control rate (BCR) was evaluated using multivariate regression model and Kaplan-Meier analysis. RESULTS: The 10-year BCR was 59% versus 82% in AA and CS men, respectively (P = .003). There was no significant difference in extraprostatic spread (P = .14), positive surgical margin (P = .81), lymph node involvement (P = .71), or adverse pathologic features (P = .16) across race groups. However, among patients with ≥ 1 adverse pathologic features, AA men had higher rate of seminal vesicle invasion (SVI) compared with CS men (51% vs. 30%; P = .01). After adjusting for known predictors of adverse pathologic features AA race remained a predictor of SVI. CONCLUSION: AA men have an increased risk of SVI after RP, particularly among men with Gleason ≤ 6 disease. This might represent racial differences in the biology of PCa disease progression, which contribute to poorer outcomes in AA men.

Mechanical stretch upregulates proteins involved in Ca2+ sensitization in urinary bladder smooth muscle hypertrophy.

Partial bladder outlet obstruction (pBOO)-induced remodeling of bladder detrusor smooth muscle (DSM) is associated with the modulation of cell signals regulating contraction. We analyzed the DSM from obstructed murine urinary bladders for the temporal regulation of RhoA GTPase and Rho-activated kinase (ROCK), which are linked to Ca(2+) sensitization. In addition, the effects of equibiaxial cell stretch, a condition thought to be associated with pBOO-induced bladder wall smooth muscle hypertrophy and voiding frequency, on the expression of RhoA, ROCK, and C-kinase-activated protein phosphatase I inhibitor (CPI-17) were investigated. DSM from 1-, 3-, 7-, and 14-day obstructed male mice bladders and benign prostatic hyperplasia (BPH)-induced obstructed human bladders revealed overexpression of RhoA and ROCK-ß at the mRNA and protein levels compared with control. Primary human bladder myocytes seeded onto type I collagen-coated elastic silicone membranes were subjected to cyclic equibiaxial stretch, mimicking the cellular mechanical stretch in the bladder in vivo, and analyzed for the expression of RhoA, ROCK-ß, and CPI-17. Stretch caused a significant increase of RhoA, ROCKß, and CPI-17 expression. The stretch-induced increase in CPI-17 expression occurs at the transcriptional level and is associated with CPI-17 promoter binding by GATA-6 and NF-κB, the transcription factors responsible for CPI-17 gene transcription. Cell stretch caused by bladder overdistension in pBOO is the likely mechanism for initiating overexpression of the signaling proteins regulating DSM tone.

LIMD2 is a small LIM-only protein overexpressed in metastatic lesions that regulates cell motility and tumor progression by directly binding to and activating the integrin-linked kinase.

Proteins that communicate signals from the cytoskeleton to the nucleus are prime targets for effectors of metastasis as they often transduce signals regulating adhesion, motility, and invasiveness. LIM domain proteins shuttle between the cytoplasm and the nucleus, and bind to partners in both compartments, often coupling changes in gene expression to extracellular cues. In this work, we characterize LIMD2, a mechanistically undefined LIM-only protein originally found to be overexpressed in metastatic lesions but absent in the matched primary tumor. LIMD2 levels in fresh and archival tumors positively correlate with cell motility, metastatic potential, and grade, including bladder, melanoma, breast, and thyroid tumors. LIMD2 directly contributes to these cellular phenotypes as shown by overexpression, knockdown, and reconstitution experiments in cell culture models. The solution structure of LIMD2 that was determined using nuclear magnetic resonance revealed a classic LIM-domain structure that was highly related to LIM1 of PINCH1, a core component of the integrin-linked kinase-parvin-pinch complex. Structural and biochemical analyses revealed that LIMD2 bound directly to the kinase domain of integrin-linked kinase (ILK) near the active site and strongly activated ILK kinase activity. Cells that were null for ILK failed to respond to the induction of invasion by LIMD2. This strongly suggests that LIMD2 potentiates its biologic effects through direct interactions with ILK, a signal transduction pathway firmly linked to cell motility and invasion. In summary, LIMD2 is a new component of the signal transduction cascade that links integrin-mediated signaling to cell motility/metastatic behavior and may be a promising target for controlling tumor spread.

GATA-6 and NF-κB activate CPI-17 gene transcription and regulate Ca2+ sensitization of smooth muscle contraction.

Protein kinase C (PKC)-potentiated inhibitory protein of 17 kDa (CPI-17) inhibits myosin light chain phosphatase, altering the levels of myosin light chain phosphorylation and Ca(2+) sensitivity in smooth muscle. In this study, we characterized the CPI-17 promoter and identified binding sites for GATA-6 and nuclear factor kappa B (NF-κB). GATA-6 and NF-κB upregulated CPI-17 expression in cultured human and mouse bladder smooth muscle (BSM) cells in an additive manner. CPI-17 expression was decreased upon GATA-6 silencing in cultured BSM cells and in BSM from NF-κB knockout (KO) mice. Moreover, force maintenance by BSM strips from KO mice was decreased compared with the force maintenance of BSM strips from wild-type mice. GATA-6 and NF-κB overexpression was associated with CPI-17 overexpression in BSM from men with benign prostatic hyperplasia (BPH)-induced bladder hypertrophy and in a mouse model of bladder outlet obstruction. Thus, aberrant expression of NF-κB and GATA-6 deregulates CPI-17 expression and the contractile function of smooth muscle. Our data provide insight into how GATA-6 and NF-κB mediate CPI-17 transcription, PKC-mediated signaling, and BSM remodeling associated with lower urinary tract symptoms in patients with BPH.

Detrusor overactivity is associated with downregulation of large-conductance calcium- and voltage-activated potassium channel protein.

Large-conductance voltage- and calcium-activated potassium (BK) channels have been shown to play a role in detrusor overactivity (DO). The goal of this study was to determine whether bladder outlet obstruction-induced DO is associated with downregulation of BK channels and whether BK channels affect myosin light chain 20 (MLC(20)) phosphorylation in detrusor smooth muscle (DSM). Partial bladder outlet obstruction (PBOO) was surgically induced in male New Zealand White rabbits. The rabbit PBOO model shows decreased voided volumes and increased voiding frequency. DSM from PBOO rabbits also show enhanced spontaneous contractions compared with control. Both BK channel alpha- and beta-subunits were significantly decreased in DSM from PBOO rabbits. Immunostaining shows BKbeta mainly expressed in DSM, and its expression is much less in PBOO DSM compared with control DSM. Furthermore, a translational study was performed to see whether the finding discovered in the animal model can be translated to human patients. The urodynamic study demonstrates several overactive DSM contractions during the urine-filling stage in benign prostatic hyperplasia (BPH) patients with DO, while DSM is very quiet in BPH patients without DO. DSM biopsies revealed significantly less BK channel expression at both mRNA and protein levels. The degree of downregulation of the BK beta-subunit was greater than that of the BK alpha-subunit, and the downregulation of BK was only associated with DO, not BPH. Finally, the small interference (si) RNA-mediated downregulation of the BK beta-subunit was employed to study the effect of BK depletion on MLC(20) phosphorylation. siRNA-mediated BK channel reduction was associated with an increased MLC(20) phosphorylation level in cultured DSM cells. In summary, PBOO-induced DO is associated with downregulation of BK channel expression in the rabbit model, and this finding can be translated to human BPH patients with DO. Furthermore, downregulation of the BK channel may contribute to DO by increasing the basal level of MLC(20) phosphorylation.

Single-center experience of caval thrombectomy in patients with renal cell carcinoma with tumor thrombus extension into the inferior vena cava.

The objective of this study is to describe a single-center experience of caval thrombectomy in patients with renal cell carcinoma (RCC) and tumor thrombus extension into the inferior vena cava (IVC). We retrospectively reviewed 23 patients undergoing radical nephrectomy with caval thrombectomy. Follow-up included an office visit and computed tomography scan. Statistical comparisons were made using 2-sample t tests. Patients' ages ranged from 32 to 83 years (mean, 62 years; 18 male, 5 female). Tumor size ranged from 3 to 21 cm (mean, 8.6 cm). Tumor thrombus staging was based on the Nevus classification: level I (2/23), II (6/23), III (13/26), IV (2/23). Tumor thrombi were removed by means of digital extraction (20), Fogarty embolectomy (2), or endarterectomy (1-caval wall invasion). Lateral venorrhaphy was used for IVC repair in all cases. Hepatic mobilization and suprahepatic clamping were necessary in 14 patients. Clamp times were significantly different between the suprahepatic (SH) and infrahepatic (IH) groups (15 vs 9.4 minutes, P < .012). Mean blood loss was also significantly different (3.2 L vs 2 L, P < .045). In the SH group, 2 patients developed postoperative atrial fibrillation and 2 patients died (respiratory failure; missed enterotomy). The IH group had no perioperative morbidity or mortality. Median followup was 15 months (range, 1-54 months). Follow-up imaging was available for 19/23 patients. Ninety-five percent of patients had a patent IVC (18). One SH patient developed an IVC stenosis/thrombosis 12 months postoperatively with successful thrombolysis and stenting. There was a 16% (3/19) recurrence rate in follow-up, with all patients demonstrating renal vascular invasion and high Fuhrman grade upon final pathologic evaluation. Caval thrombectomy can be performed safely during radical nephrectomy for RCC with tumor thrombus extension. The need for suprahepatic clamping is associated with longer clamp times, increased blood loss, and increased morbidity and mortality. Lateral venorrhaphy with primary repair avoids complicated caval reconstructions and results in high patency rates, despite a not insignificant recurrence rate.

The presence of lymphovascular invasion in radical cystectomy specimens from patients with urothelial carcinoma portends a poor clinical prognosis.

OBJECTIVES: To assess the prognostic significance of lymphovascular invasion (LVI) on clinical outcomes in patients with transitional cell carcinoma of the bladder treated with radical cystectomy (RC). PATIENTS AND METHODS: We retrospectively evaluated a prospectively maintained and authorised cystectomy database; the presence or absence of LVI was determined by pathological examination of the RC specimen. Cox regression analysis and Kaplan-Meier tables were developed to evaluate the contribution of LVI to clinical outcomes. RESULTS: In all, we analysed 356 patients treated with RC and urinary diversion between 1988 and 2006, with a mean follow-up of 45.6 months. Of these patients, 242 (68%) had no evidence of LVI in the RC specimen, whereas 114 (32%) had LVI. Patients with LVI tended to present with higher pathological stage; 84 (74%) had pT3 or pT4 disease. On univariable analysis the presence of LVI conferred a significant risk for decreased overall, cancer-specific and recurrence-free survival (P < 0.001); the mean values for LVI-negative patients were 96.8, 157.4, and 135.0 months, respectively, vs LVI-positive patients, whose survival times were 52.3, 82.7 and 75.2 months, respectively. The multivariable analysis showed significant independent risk for cancer-specific and overall survival for patients who were LVI-positive and had no lymph-node metastases. The hazard ratios (95% confidence interval) were 1.63 (1.06-2.51, P < 0.026) and 1.81 (1.06-3.08, P < 0.03) for overall and disease-specific survival, respectively. CONCLUSIONS: The presence of LVI in the pathological RC specimen confers significant independent risk for reduced bladder cancer-specific and overall survival. This variable could be used to prospectively stratify patients who would benefit from adjuvant chemotherapy.

Radiofrequency ablation of small renal cell carcinomas using multitined expandable electrodes: preliminary experience.

PURPOSE: Radiofrequency ablation is a minimally invasive, nephron-sparing option for renal cell carcinoma (RCC) in poor surgical candidates. We report our contemporary experience with RCC radiofrequency ablation using multitined expandable electrodes along with an aggressive treatment strategy to displace adjacent viscera away from probe tines. Involution of the treatment zone was assessed over time. MATERIALS AND METHODS: Over a 36-month period, a quality-assurance database identified 22 patients with 26 sporadic RCC who underwent 43 ablations during 27 radiofrequency ablation sessions. The mean age of the cohort was 71 years (range, 47-89 y). Mean RCC diameter was 2.2 cm (range, 1-4 cm). Twenty-six of radiofrequency ablation sessions were performed using multitined expandable electrodes. All ablations used CT guidance with moderate sedation. Adjunctive techniques used during ablation were recorded, as were instances in which ablation mandated penetration of tines beyond the kidney margin. Post-treatment ablation zones were measured from CT/MR images to evaluate serial involution and treatment response. RESULTS: Technical success in targeting and ablation was 100%. Follow-up periods ranged from 1 to 31 months (mean, 11.2). During this period, one patient presented with marginal local recurrence and underwent repeat radiofrequency ablation. Adjunctive techniques in four patients included water injection for displacement of the tail of the pancreas (n = 1) or descending colon (n = 3). Deliberate penetration of tines beyond the margins of the kidney was performed in 41% of cases; no hemorrhage occurred in these cases. No major complications occurred. Minor complications occurred in 17% of patients, including asymptomatic pneumothorax, perirenal hematomas, subcutaneous hematoma, and subcutaneous abscess. After 6 months, mean involution of the ablation zone was 15% from baseline volume per year. CONCLUSION: Multitined expandable radiofrequency electrodes produce a high rate of local control for small RCCs with a low complication rate, even when tine penetration of the kidney is required for an adequate tumor treatment margin. Adjacent organs can be protected with adjunctive percutaneous maneuvers.

In-vivo light dosimetry of interstitial PDT of human prostate.

We report results of in-vivo light dosimetry of light fluence (rate) in human prostate during photodynamic therapy (PDT). Measurements were made in-vivo at the treatment wavelength (732nm) in 15 patients in three to four quadrants using isotropic detectors placed inside catheters inserted into the prostate. The catheter positions are determined using a transrectal ultrasound (TRUS) unit attached to a rigid template with 0.5-cm resolution. Cylindrical diffusing fibers with various lengths are introduced into the catheters to cover the entire prostate gland. For the last four patients, distributions of light fluence rate along catheters were also measured using a computer controlled step motor system to move multiple detectors to different distances (with 0.1 mm resolution). To predict the light fluence rate distribution, a kernel-based model was used to calculate light fluence rate using either (a) the mean optical properties (assuming homogeneous optical properties) for all patients or (b) using distributions of optical properties measured for latter patients. Standard deviations observed between the calculations and measurements were 56% and 34% for (a) and (b), respectively. The study shows that due to heterogeneity of optical properties significant variations of light fluence rate were observed both intra and inter prostates. However, if one assume a mean optical properties (µa = 0.3 cm-1, µs' = 14 cm-1), one can predict the light fluence rate to within a maximum error 200% for 80% of the cases and a mean error of 105%. To improve the prediction of light fluence rate further would require determination of distribution of optical properties.

Lung cancer: intragenic ERBB2 kinase mutations in tumours.

The protein-kinase family is the most frequently mutated gene family found in human cancer and faulty kinase enzymes are being investigated as promising targets for the design of antitumour therapies. We have sequenced the gene encoding the transmembrane protein tyrosine kinase ERBB2 (also known as HER2 or Neu) from 120 primary lung tumours and identified 4% that have mutations within the kinase domain; in the adenocarcinoma subtype of lung cancer, 10% of cases had mutations. ERBB2 inhibitors, which have so far proved to be ineffective in treating lung cancer, should now be clinically re-evaluated in the specific subset of patients with lung cancer whose tumours carry ERBB2 mutations.

Using PSA, biopsy Gleason score, clinical stage, and the percentage of positive biopsies to identify optimal candidates for prostate-only radiation therapy.

PURPOSE: An identification of prostate cancer patients most likely to benefit from prostate-only radiation was made based upon the pretreatment prostate-specific antigen (PSA), biopsy Gleason score, clinical stage, percentage of positive biopsies, and the 5-year postoperative PSA outcome. METHODS: Between 1989 and 2000, 2099 patients underwent radical prostatectomy for clinically localized prostate cancer. The primary end points were pathologic evidence of seminal vesicle invasion 2(SVI), extracapsular extension (ECE) with or without positive surgical margins, and the 5-year postoperative PSA outcome. RESULTS: Pretreatment PSA, biopsy Gleason score, and clinical stage were used to assign patients to low-, intermediate-, and high-risk groups. These risk groups were stratified by the percentage of positive biopsies and the primary pathologic and biochemical outcomes examined. The rates of SVI, ECE with positive margin, and no biochemical evidence of disease (bNED) for low-risk patients with < or =50% positive biopsies were 2%, 7%, and 93%, respectively. Patients with >50% positive biopsies had higher rates of SVI and ECE (5% and 11%, respectively) and 52% bNED (p < 0.0001). For intermediate-risk patients with < or =17% positive biopsies, the rates of SVI, ECE with positive margin, and bNED were 3%, 9%, and 90%, respectively. As the percentage of positive biopsies increased above 17% in intermediate-risk patients, there was a statistically significant increase in SVI and ECE and a significant decrease in bNED. CONCLUSIONS: Low-risk patients with < or =50% positive biopsies and intermediate-risk patients with < or =17% positive biopsies had a very low risk of SVI and ECE with positive surgical margins. Given that the presence of SVI and ECE with positive surgical margins was uncommon (<10%) with a > or =90% PSA failure-free survival after radical prostatectomy, these patients may be optimal candidates for radiation therapy directed at the prostate only (prostate gland + 1.5-cm margin).