Natural and anthropogenic controls on sediment composition of an arid coastal environment: Sharm Obhur, Red Sea, Saudi Arabia

The present study investigated the natural and anthropogenic processes that control the composition of the bottom sediments of Sharm Obhur, Red Sea. Mineralogical analysis using XRD indicated that the sediments consist of carbonate and non-carbonate minerals. Elemental interrelationships allowed differentiating two groups of elements of different sources and origin. Elements that are in the same group are positively correlated, while they correlate negatively with elements of the other group. The first group includes silicon, Al, Fe, Mn, Mg, vanadium (V), chromium (Cr), Co, Ni, Cu, and Zn, whereas the other group includes Ca, Sr, and CaCO3. The highest concentration levels of the first group and the highest content of non-carbonate minerals were obtained from the sediments near the head of the sharm (zone A), whereas the sediments near the mouth of the sharm (zone B) yielded high concentrations of second group and carbonate minerals. Metal enrichment and contamination factors and pollution load index were calculated. The values of these indices differentiate two groups of metals: lithogenic and non-lithogenic. Except for lead (Pb) at one sampling site, metals in zone A sediments are of lithogenic source, supplied to the sharm either naturally by aeolian transportation and through Wadi Al-Kuraa'a during rare but major floods or by human activities such as dumping and shore protection. Non-lithogenic Cr, Pb, V, and Mn were documented from some sampling sites in zone B, and their occurrences are related to waste disposal and fossil fuel combustion.

Long-term treatment efficacy in primary inflammatory breast cancer by hormonal receptor- and HER2-defined subtypes

BACKGROUND

Subtypes defined by hormonal receptor (HR) and HER2 status have not been well studied in inflammatory breast cancer (IBC). We characterized clinical parameters and long-term outcomes, and compared pathological complete response (pCR) rates by HR/HER2 subtype in a large IBC patient population. We also compared disease-free survival (DFS) and overall survival (OS) between IBC patients who received targeted therapies (anti-hormonal, anti-HER2) and those who did not.

PATIENTS AND METHODS

We retrospectively reviewed the records of patients diagnosed with IBC and treated at MD Anderson Cancer Center from January 1989 to January 2011. Of those, 527 patients had received neoadjuvant chemotherapy and had available information on estrogen receptor (ER), progesterone receptor (PR), and HER2 status. HR status was considered positive if either ER or PR status was positive. Using the Kaplan-Meier method, we estimated median DFS and OS durations from the time of definitive surgery. Using the Cox proportional hazards regression model, we determined the effect of prognostic factors on DFS and OS. Results were compared by subtype.

RESULTS

The overall pCR rate in stage III IBC was 15.2%, with the HR-positive/HER2-negative subtype showing the lowest rate (7.5%) and the HR-negative/HER2-positive subtype, the highest (30.6%). The HR-negative, HER2-negative subtype (triple-negative breast cancer, TNBC) had the worst survival rate. HR-positive disease, irrespective of HER2 status, had poor prognosis that did not differ from that of the HR-negative/HER2-positive subtype with regard to OS or DFS. Achieving pCR, no evidence of vascular invasion, non-TNBC, adjuvant hormonal therapy, and radiotherapy were associated with longer DFS and OS.

CONCLUSIONS

Hormone receptor and HER2 molecular subtypes had limited predictive and prognostic power in our IBC population. All molecular subtypes of IBC had a poor prognosis. HR-positive status did not necessarily confer a good prognosis. For all IBC subtypes, novel, specific treatment strategies are needed in the neoadjuvant and adjuvant settings.

Abstract P6-12-11: Celecoxib inhibits the growth of IBC tumors by suppressing the regulation of cancer stem-like cells by nodal

Background: Inflammatory breast cancer (IBC) is an aggressive type of breast cancer with no known molecular targets for treatment. Although erythema is commonly associated with IBC, the molecular mechanism of inflammation in the pathogenesis of IBC remains unknown. We have previously shown that EGFR is an emerging target in IBC (Zhang D. et al Clin Can Res 2009). As crosstalk between EGFR and COX-2 plays an important role in the inflammatory response in several cancers, including breast cancer, we hypothesized that COX-2 promotes the tumorigenesis and metastasis of IBC cells.

Methods: Using clinically derived IBC and non-IBC tumor samples, a Spearman's Rank correlation coefficient analysis was performed to analyze the expression levels of COX-2 and EGFR in IBC and non-IBC. The levels of COX-2 metabolites, prostaglandins (PGs) PGE2 and PGF2α, were measured in IBC and non-IBC cell lines by HPLC/MS method. Cell migration and invasion assays were performed using SUM149 and KPL-4 IBC cell lines treated with PGs or the COX-2 inhibitor, celecoxib. We evaluated the epithelial to mesenchymal transition (EMT)-like phenotype in 3D culture of SUM149 cells treated with celecoxib, and the stem-like population by mammosphere formation, and CD44+/CD24− and aldefluor+ population by FACS. We treated preclinical IBC xenograft mice with celecoxib and measured tumor growth, PGs levels, and the expression of EMT protein markers. Nodal, a stem cell regulator and potential biomarker for breast cancer progression, was evaluated in IBC cells following treatment with celecoxib and recombinant Nodal or transfection with Nodal cDNA.

Results: EGFR and COX-2 expression levels positively correlated within IBC, but not non-IBC tumors. Elevated levels of PGE2 and PGF2α were identified in multiple IBC cell lines suggesting that COX activity is elevated within IBC compared to non-IBC cells. PGs altered EMT protein markers and promoted cell migration and invasion, while Celecoxib inhibited EMT and migration and invasion in SUM149 and KPL-4 cells. Celecoxib treatment inhibited tumor growth in mice, and downregulated the expression of EMT protein markers, including Nodal. Celecoxib decreased the stem-like CD44+/CD24−, and aldefluor+ population and the formation of mammospheres. Exogenous Nodal mitigated the effects of celecoxib on cell migration and invasion and the stem-like population in SUM149 cells.

Conclusion: We conclude that activation of the COX-2 inflammatory signaling pathway is critical in the development and progression of IBC. This study provides a novel insight into how inflammation may regulate cancer stem cells via Nodal, and will guide future research into the development of stem cell targeted therapies for IBC.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-12-11.

Abstract P6-12-02: Survival differences between patients with metastatic inflammatory and non-inflammatory breast cancer

Background: Very little is known about the survival of patients with inflammatory breast cancer (IBC) and distant metastasis. Furthermore, the American Joint Committee on Cancer classification of breast cancer does not recognize metastatic IBC as a distinct entity within stage IV. We hypothesized that the survival of patients with IBC and distant metastasis is worse than the survival of patients with stage-matched non-IBC.

Patients and Methods: We retrospectively reviewed 5314 consecutive patients with stage III or IV breast cancer (IBC or non-IBC) who were treated at our institution between 1986 and 2012. A total of 1079 patients presented with IBC (stage III: 861; stage IV: 218) and 4235 non-IBC (stage III: 2781; stage IV: 1454). We compared the time to distant metastasis from initial diagnosis, distant metastasis–free survival (DMFS), and overall survival (OS) in stage-matched patients with IBC or non-IBC.

Results: The median follow-up periods were 3.3 years for patients with stage III disease (range, 0-32.2 years) and 1.8 years for patients with stage IV disease (range, 0-19.9 years). The total number of recorded events (metastasis/death) was 1657 for stage III, while the numbers of deaths for stage III and IV were 1337 and 973, respectively. In patients with stage III, the time to distant metastasis was shorter in IBC than in non-IBC (median 1.3 vs. 1.7 years, P < .001). DMFS and OS were shorter in patients with stage III IBC than in those with stage III non-IBC (2.5 vs. 6.9 years, P < .001; and 4.7 vs. 8.9 years, P < .001; respectively). However, there was no significant difference in OS after development of distant metastasis between stage III IBC and non-IBC (median for both 1.3 years, P = .83). In multivariate analysis, the diagnosis of IBC remained significantly associated with mortality after adjusting for potential confounders. De novo stage IV IBC presented more frequently with multiple sites of metastasis than de novo stage IV non-IBC (P = .02). In patients with de novo stage IV disease, OS was shorter in IBC than in non-IBC (2.3 vs. 3.4 years, P = .004). In the multicovariate Cox model, while ethnicity, tumor grade, hormone receptor status and HER2 status, site of metastasis, number of sites of metastasis, and definitive breast surgery by 1 year were all significant factors in OS for stage IV breast cancer, the diagnosis of IBC conferred a hazard ratio of 1.33 (95% confidence interval: 1.05 - 1.69) in multivariate analysis.

Conclusion: Our findings suggest that IBC patients with metastasis at diagnosis have worse outcomes than stage-matched non-IBC patients. IBC patients presenting with de novo stage IV disease should be considered as a separate subcategory of stage IV in the tumor-node-metastasis classification because their clinical course and prognosis are different from those of patients with stage IV non-IBC.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-12-02.

Gene expression profiles of inflammatory breast cancer: correlation with response to neoadjuvant chemotherapy and metastasis-free survival

BACKGROUND

Inflammatory breast cancer (IBC) is an aggressive disease. To date, no molecular feature reliably predicts either the response to chemotherapy (CT) or the survival. Using DNA microarrays, we searched for multigene predictors.

PATIENTS AND METHODS

The World IBC Consortium generated whole-genome expression profiles of 137 IBC and 252 non-IBC (nIBC) samples. We searched for transcriptional profiles associated with pathological complete response (pCR) to neoadjuvant anthracycline-based CT and distant metastasis-free survival (DMFS) in respective subsets of 87 and 106 informative IBC samples. Correlations were investigated with predictive and prognostic gene expression signatures published in nIBC (nIBC-GES). Supervised analyses tested genes and activation signatures of 19 biological pathways and 234 transcription factors.

RESULTS

Three of five tested prognostic nIBC-GES and the two tested predictive nIBC-GES discriminated between IBC with and without pCR, as well as two interferon activation signatures. We identified a 107-gene signature enriched for immunity-related genes that distinguished between responders and nonresponders in IBC. Its robustness was demonstrated by external validation in three independent sets including two IBC sets and one nIBC set, with independent significant predictive value in IBC and nIBC validation sets in multivariate analysis. We found no robust signature associated with DMFS in patients with IBC, and neither of the tested prognostic GES, nor the molecular subtypes were informative, whereas they were in our nIBC series (220 stage I-III informative samples).

CONCLUSION

Despite the relatively small sample size, we show that response to neoadjuvant CT in IBC is, as in nIBC, associated with immunity-related processes, suggesting that similar mechanisms responsible for pCR exist. Analysis of a larger IBC series is warranted regarding the correlation of gene expression profiles and DMFS.

Silencing of P-glycoprotein increases mortality in temephos-treated Aedes aegypti larvae

Re-emergence of vector-borne diseases such as dengue and yellow fever, which are both transmitted by the Aedes aegypti mosquito, has been correlated with insecticide resistance. P-glycoproteins (P-gps) are ATP-dependent efflux pumps that are involved in the transport of substrates across membranes. Some of these proteins have been implicated in multidrug resistance (MDR). In this study, we identified a putative P-glycoprotein in the Ae. aegypti database based on its significantly high identity with Anopheles gambiae, Culex quinquefasciatus, Drosophila melanogaster and human P-gps. The basal ATPase activity of ATP-binding cassette transporters in larvae was significantly increased in the presence of MDR modulators (verapamil and quinidine). An eightfold increase in Ae. aegypti P-gp (AaegP-gp) gene expression was detected in temephos-treated larvae as determined by quantitative PCR. To analyse the potential role of AaegP-gp in insecticide efflux, a temephos larvicide assay was performed in the presence of verapamil. The results showed an increase of 24% in temephos toxicity, which is in agreement with the efflux reversing effect. RNA interference (RNAi)-mediated silencing of the AaegP-gp gene caused a significant increase in temephos toxicity (57%). In conclusion, we have demonstrated for the first time in insects that insecticide-induced P-gp expression can be involved in the modulation of insecticide efflux.

Abstract PD03-08: Statin use and improved outcome in primary inflammatory breast cancer: retrospective cohort study

Background Inflammatory breast cancer (IBC) is the most aggressive type of breast cancer. HMG-CoA reductase inhibitors (statins) are cholesterol reducing agents with pleiotropic effects, including antitumorigenic and anti-inflammatory properties. We hypothesized that statins reduce the metastatic potential in primary IBC.

Methods We retrospectively reviewed 724 patients diagnosed with and treated for primary IBC at The University of Texas MD Anderson Cancer Center between Jan. 12, 1995 and Jan. 27, 2011. Patients with records indicating statin use at the time of IBC diagnosis on the electronic medical record were compared with those without. We further compared outcomes stratified by statin type (hydrophilic [H] versus lipophilic [L]). We used the Kaplan-Meier method to estimate the median disease-free survival (DFS) after surgery, overall survival (OS), and disease specific survival (DSS), followed by Cox proportional hazards regression model to test statistical significance of several potential prognostic factors.

Results For primary IBC patients who had information on their statin use status at IBC diagnosis, the median DFS time were 4.88 years, 2.47 years and 1.76 years (P= 0.04); the median OS time 5.05 years, 3.79 years and 4.32 years (P= 0.35); and the median DSS time 5.10 years, 3.79 years and 4.52 years (P= 0.37), for patients who took “ H”, “L” and no statin, respectively. In multivariable Cox model stratified by radiation therapy, ER/PR status and HER2 status, statin “H” use was associated with significantly improved DFS compared to no statin use (HR=0.49; 95% CI: 0.28–0.84; p<0.01), adjusted for lymphatic/vascular invasion. Although there is a trend that patients who used statin “H” had a longer time to death compared to patients who did not take statin, it did not reach statistical significance for OS (HR=0.80; 95% CI: 0.43–1.49; p=0.49) and DSS (HR=0.85; 95% CI: 0.46–1.57, p=0.59) after adjustment for lymphatic/vascular invasion, nuclear grade and surgery status within one year.

Conclusions Hydrophilic statin use was associated with improved DFS. There was a trend for reduced HR in OS and DSS among primary IBC patient who used hydrophilic statins. A prospective randomized study to evaluate the potential survival benefits of statins in primary IBC population is warranted.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD03-08.

Abstract P3-10-05: Response to neoadjuvant systemic therapy (NST) in inflammatory breast cancer (IBC) according to estrogen receptor (ER) and HER2 expression

Background: Inflammatory breast cancer (IBC) is the most aggressive form breast cancer. NST, followed by local therapy (surgery and radiation therapy), is considered the current standard therapy for IBC. Among noninflammatory breast cancers, sensitivity to NST differs based on ER and HER2 status. However, whether the sensitivity to NST also differs in primary IBC based on ER status or other prognostic factors has not been studied in a large cohort.

Methods: We retrospectively reviewed 1078 patients (pts) newly diagnosed with IBC from April 1989 to January 2011. Of these, 838 pts met our inclusion criterion of stage III disease at diagnosis, and 713 of these pts had received NST and surgery. Among this population, 545 pts had information available on both ER and HER2 status. We compared pathological complete response (pCR) rates (defined as no evidence of invasive disease in the breast and ipsilateral axillary limph nodes) and clinical characteristics between ER and HER2-status subgroups and analyzed their clinical outcome. We used the Kaplan-Meier method to estimate the median recurrence-free survival (RFS) after surgery and overall survival (OS), and the Cox proportional hazards regression model to test the statistical significance of potential prognostic factors in each group.

Results: Overall 177 pts had ER+HER2− tumors; 75, ER+HER2+; 134, ER-HER2+; and 159, ER-HER2−. NST consisted of anthracycline-based [A] alone, a taxane [T] alone or with A+T; HER2 targeting therapies (H) were administered to 117 patients with HER2-positive breast cancer after 1998. Overall pCR rate was 14.7%. pCR rates are shown by marker subtype and NST received in the table below. pCR rate, nuclear grade, vascular invasion, clinical response to NST, adjuvant treatment, radiation therapy, and adjuvant hormonal therapy differed significantly among subgroups.

The median RFS and OS for all patients was 19.2 and 33.2 months, respectively. In multivariate analysis, BMI, ER status, lymphatic invasion, radiation therapy, and pCR rate were associated with RFS, and ER status, vascular invasion, radiation therapy, and pCR rate were associated with OS. Except in the ER+HER2− group, pCR was associated with better prognosis compared to non-pCR. Adjuvant hormonal therapy improved RFS both in ER+HER2+ and ER+HER2− groups, but did not improve OS in the ER+HER2+ group. Among 209 patients with HER2+ IBC, 134 received HER2 targeting therapies in neoadjuvant or adjuvant chemotherapy, and had a trend to improvement in RFS compared to chemotherapy alone (p = 0.082). The ER-HER2− group showed poorest outcome compared to other subgroups (P < 0.001).

Conclusions: Sensitivity to NST differs depending on the ER and HER2 status in IBC pts. pCR rates based on these subgroups appear to be low. There is a need more effective treatments in the neoadjuvant and adjuvant therapies for all subgroups of IBC.

Abstract P5-03-09: Receptor Activator of Nuclear Factor Kappa B (RANK) as a potential therapeutic target in triple-negative breast cancer

Background: Triple-negative breast cancer (TNBC) has a poorer prognosis in comparison to other breast cancer subtypes because of its high metastatic rate. There is evidence that cancer stem cells (CSCs), known to have an epithelial-to-mesenchymal (EMT) phenotype, may contribute to the metastasis of breast cancer. Denosumab (an anti-RANK ligand antibody) is currently being explored as a treatment for breast cancer in phase II and III clinical trials. RANK is thought to regulate mammary stem cells. Therefore, we hypothesized that RANK promotes tumorigenicity and metastasis of TNBC via the regulation of EMT and enrichment of CSCs. We sought to determine the effects of RANK expression on the tumorigenic and metastatic activities of TNBC cells and whether RANK is a potential therapeutic target in TNBC.

Methods: Primary breast tumor specimens from the MD Anderson Cancer Center Tumor Bank were stratified by ER/HER2 status. We analyzed RANK mRNA expression levels, obtained by Affymetrix gene chip array, in ER+/HER2-negative breast tumors (n = 22) and ER−/HER2-negative breast tumors including TNBC tumors (n = 18). To study the effects of RANK suppression in TNBC cells, we generated two stable RANK shRNA MDA-MB-231 TNBC cell lines and a negative shRNA cell line as a control and examined whether knockdown of RANK expression correlated with a decrease in mesenchymal markers, vimentin and snail, and stem cell marker, ALDH1, invasion, migration, and tumorigenicity in TNBC cells.

Results: An analysis of RANK mRNA expression levels among human primary breast cancer specimens revealed increased RANK expression in ER−/HER2-negative primary breast tumors including TNBC tumors, compared with ER+/HER2-negative primary breast tumors (p = 0.034). Knocking down RANK in MDA-MB-231 cells significantly inhibited migration (p = 0.0005) and invasion (p = 0.0006) and reduced the stem cell subpopulation, as shown by a decrease in mammospheres (p = 0.0188) and ALDH1 activity. Further, in a three-dimensional (3D) cell culture model, we observed significant inhibition of projections in MDA-MB-231 cells with knockdown of RANK (p < 0.05), which correlated with downregulation of the mesenchymal markers vimentin and snail shown by qRT PCR analysis.

Conclusion: Our data demonstrate that RANK may promote the tumorigenesis of TNBC by enriching cancer stem cells. In future studies, we will investigate the effect of RANK inhibition on metastasis in vivo using a TNBC xenograft model. Our long-term goal is to develop RANK-targeted therapy for TNBC.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-03-09.

Blood lead levels in Japanese children: Effects of passive smoking

Blood lead levels (BLLs) of 188 pediatric patients were measured and their parents were queried as to the smoking style in their home. Their mean BLL was 3.16 μg/dl, which was among the lowest levels in the world, and none of them had levels of over 10 μ g/dl. Preschool children ( 1 to 6 years of age) with parents who smoked in the same room had a significantly higher BLL (mean; 4.15 μ g/dl) than those with parents who never smoked (mean; 3.06 μ g/dl) (P<0.01). However, the mean BLL of school children (6 to 15 years of age) with parents who smoked in the same room was not significantly different from that of school children with parents who never smoked. Passive smoking caused an increase of the BLL only in preschool children in Japan. This is probably because preschool infants spend much more time with their parents and have much more contact with passive smoking than school children and, additionally young infants have a limited ability to excrete lead from the body.

Characterization of three propane-inducible oxygenases in Mycobacterium sp. strain ENV421

AIMS

Mycobacterium sp. strain ENV421 has the ability to cometabolize a variety of chemicals following growth on propane as a sole source of carbon and energy. In this study, we used genetic and biochemical approaches to identify and characterize multiple propane-inducible oxygenase genes in ENV421.

METHODS AND RESULTS

 Gene clusters encoding a CYP153-type cytochrome P450 oxygenase (P450), an AlkB-type alkane monooxygenase (AlkB) and a soluble diiron monooxygenase were identified and cloned using degenerate PCR primers. Reverse transcriptase PCR showed that all three gene clusters were induced by propane. Substrate specificity studies revealed that despite the fact that ENV421 does not grow on medium length alkanes, cloned versions of both the AlkB and P450 were capable of octane oxidation, forming n-octanol. Additionally, the P450 oxygenase had the ability to oxidize indole, medium-to-long-chain alkylbenzenes and a variety of para-substituted methylalkylbenzenes. Successful cloning and expression of the diiron monooxygenase was not achieved, so its substrate specificity could not be determined.

CONCLUSIONS

Three types of short-to-medium-chain alkane oxygenases were induced by propane in ENV421, even though the cloned AlkB and P450 oxygenases did not oxidize propane. Curiously, they both oxidized octane, which is not a growth substrate for ENV421. Furthermore, the P450, typically operating as terminal alkane hydroxylase, exhibited interesting regio- and stereoselectivity, catalysing linear alkanes, alkylbenzenes and indole.

SIGNIFICANCE AND IMPACT OF THE STUDY

 This study describes the first example of a propane-inducible P450 with a broad substrate specificity, including linear alkanes, alkylbenzenes and a multiring compound. The induction of three distinct oxygenase classes by propane is also an interesting finding because it might explain why propane serves as an effective stimulant that promotes the biodegradation of a various environmental contaminants.

A novel repeat biopsy nomogram based on three-dimensional extended biopsy

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Background: There is no perfect cohort in which nomograms are developed because no biopsy method can detect all cancers. To minimize this inherent verification bias, having a cohort with fewer false negative cases is advantageous. Based on a cohort examined with three-dimensional (3D) extended biopsy protocol, we developed a novel nomogram for diagnosis of prostate cancer on repeat biopsy.

Methods: Of 4,074 consecutive male patients undergoing prostate biopsy at our institutions between 2000 and 2009, 775 men with at least one previous negative biopsy underwent repeat biopsy with 3D protocol. Men with previous atypical glands or atypical small acinar proliferation and/or without available prostate-specific antigen (PSA) kinetics information were excluded. The remaining 515 men constituted the study cohort. We developed a logistic regression-based nomogram with 70% of the cohort selected randomly; we validated it with the remaining 30%. Predictive accuracy and performance characteristics were assessed using the area under the receiver operating characteristic curve (AUC) and calibration plots, respectively. The threshold probability was evaluated with decision curve analysis.

Results: We developed a novel repeat biopsy nomogram incorporating age, free to total PSA ratio, prostate volume, history of previous extended biopsy, and PSA doubling time. Validation confirmed predictive accuracy with an AUC value of 0.791. Calibration plots showed good agreement. The decision curve of the nomogram was superior to the decision curve of biopsying all men in a range of threshold probability over 0.15. At the threshold of 0.2, the number of unnecessary biopsies could be reduced by 10 per 100, without missing PCa.

Conclusions: We developed a novel repeat biopsy nomogram based on a cohort examined with 3D extended biopsy. This repeat biopsy nomogram is clinically beneficial, saving a substantial number of unnecessary biopsies.

No significant financial relationships to disclose.

Maintenance of the suppressed level of serum testosterone by administration of three-monthly formulations of luteinizing hormone-releasing hormone agonists at six-month intervals in Japanese patients with prostate cancer: A prospective study

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Background: Treatment with an LH-RH agonist is a standard alternative to surgical castration for prostate cancer patients. The serum testosterone level is kept at castrate levels continuously during LH-RH agonist therapy in almost all patients (Fujii Y, BJU Int 2008). LH- RH agonists, however, are more expensive than surgical castration, with drugs costing between US $300 and $500 per month in Japan. Recent studies suggest that 3-monthly formulations of LH-RH agonists suppress the serum testosterone levels far longer than the 3-month dosing interval.

Methods: A total of 43 Japanese patients with prostate cancer who were treated with 3-monthly LH-RH agonists (23 with 11.25mg leuprolide, and 20 with 10.8 mg goserelin) for one year or longer and whose testosterone levels were kept at castrate level (defined as < 50 ng/dL) were entered into this prospective, longitudinal study. After entry, the 43 men received the same 3-monthly LH-RH agonists at 6-month intervals, and had serum LH and testosterone tests performed at 3-month intervals. Bicalutamide was combined with the LH-RH agonists in 12 of the patients.

Results: At entry, median patient age was 74 years (range 59 to 89), median duration of LH-RH agonists treatment was 26 months (12 to 125), and median LH and testosterone levels were <10 ng/dL (<10 to 60) and 5 ng/dL (<5 to 18), respectively. The 43 patients received a total of 162 administrations (median 5, range 1 to 6) of the LH-RH agonists at 6-month intervals, and had a total 335 hormonal tests (median 10, range 2 to12) performed during the median followup period of 30 months. Serum LH and testosterone levels were kept suppressed during the treatment. Of the 43 patients, two had serum testosterone just above the castrate level (54 and 56 ng/dL) once each among their 12 and 8 hormonal assays, respectively.

Conclusions: Administration of 3-monthly LH-RH agonists, either leuprolide or goserelin, at 6-month intervals could maintain the castrate level of serum testosterone at least in Japanese prostate cancer patients who have received LH-RH agonists treatment for one year or longer.

No significant financial relationships to disclose.

Use of C-reactive protein to predict perinephric or renal sinus fat invasion in patients with clinical T1N0M0 renal cell carcinoma

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Background: Indication of nephron sparing surgery (NSS) for renal cell carcinoma (RCC) has been extending, as NSS can be considered for not only cT1a but also cT1b tumors. However, some cT1 diseases have pathological perinephric or renal sinus fat invasion. It is useful to know the probability of the presence of fat invasion before surgery, but diagnostic ability of imaging studies such as CT for predicting pT3a disease is limited. Therefore, estimation of the risk for pT3a disease in cT1 RCC patients could be helpful. C-reactive protein (CRP) has been shown to be a strong prognostic factor in RCC patients, reflecting tumor aggressiveness. We evaluated the predictive ability of preoperative CRP for pT3a disease in cT1N0M0 RCC patients.

Methods: Of consecutive 386 patients treated with radical nephrectomy for cT1a-bN0M0 RCC, 82 were excluded due to hemodialysis, inflammatory disease, bilateral synchronous renal tumors, synchronous other malignant disease or loss of each data. The remaining 304 patients constituted the current study cohort. Cut off point of CRP was 3 mg/L. Associations were analyzed between pT3a and preoperative factors including age, sex, BMI, laterality, tumor size, CRP, hemoglobin, platelet, LDH, ALP, calcium and albumin. We developed a multivariate model for predicting pT3a disease in cT1 RCC.

Results: Of the 304 patients, 28 (9%) had pT3a disease. Of 43 patients with elevated CRP level, 10 (23%) had pT3a disease. In contrast, of the remaining 261 patients with non-elevated CRP level, 18 (7%) had (p=0.002). Univariate and then multivariate analyses identified age (p=0.021), tumor size (p=0.007), and CRP (p=0.024) as independent and significant predictors for pT3a disease. Incorporating these three factors, we developed a predictive model for pT3a disease with predictive accuracy of area under the ROC curve of 0.772.

Conclusions: Preoperative CRP is an independent predictor for pT3a disease in cT1 RCC along with age and tumor size. The model could be useful to estimate the risk of the probability of fat invasion before surgery, especially NSS.

No significant financial relationships to disclose.

Surgical outcomes of gasless single port retroperitoneal radical nephrectomy for dialysis patients: A comparative analysis with nondialysis patients

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Background: Gasless single port retroperitoneal radical nephrectomy is minimally invasive, curative and cost effective operation which we have developed since 1998 (Eur Urol Suppl 2009; 8: 392), and covered by the Japanese universal insurance system from April, 2008. Patients necessitating dialysis are considered high risk operative candidates because of their multiple comorbidities. We compared surgical outcomes of dialysis patients with non-dialysis patients to evaluate this operation as treatment for high risk group.

Methods: We reviewed 304 consecutive patients including 59 (19.4%) dialysis patients who underwent CO2 gasless single port retroperitoneal radical nephrectomy at our institute between 2000 and 2009. Complications within the first 30 days after the surgery were graded retrospectively according to the modified Clavien classification system. Patient demographics, operative outcomes, and complications were compared between dialysis and non-dialysis patients.

Results: In all patients, the median patient age and body mass index were 60 years and 23.0 kg/m2. The median length of surgical incision, operative time (OT) and estimated blood loss (EBL) were 6.5 cm, 189 minutes and 214 mL, respectively. The transfusion rate was 3.3%. The intra and postoperative complication rate were 3.9% and 10.1%. Two grade 3a (ureteral obstruction, 1; diverticulitis, 1), three grade 3b (occlusion of peripheral hemodialysis shunt, 3) and two grade 4 (pulmonary embolism, 1; acute heart failure, 1) surgical complications occurred. In dialysis patients, the mean BMI was lower (20.4 vs. 23.3, p<0.0001), the mean OT was shorter (170 vs. 201 minutes, p<0.0001) and the mean EBL was lower (216 vs. 311mL, p<0.0001) than non-dialysis patients. There was no Clavien grade 3 or 4 surgical complications except dialysis access occlusion in dialysis patients. The average time to oral feeding and walking were equivalent, but possible discharge were longer in dialysis patients (4.3 vs. 3.4 days, p<0.0037).

Conclusions: Our data supports the safety and feasibility of gasless single port retroperitoneal radical nephrectomy for dialysis patients.

No significant financial relationships to disclose.