Defining molecular determinants of sensitivity to EGFR inhibition in urothelial carinoma

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Background: Activation of EGFR in cancer patients has been shown to correlate with tumor proliferation, angiogenesis, and metastasis. EGFR inhibition has been shown to be clinically beneficial in several solid tumors and appears to be a tractable therapeutic target. EGFR is over-expressed in bladder cancer and a phase II trial of neoadjuvant erlotinib in patients with muscle invasive bladder cancer suggests possible clinical activity. We therefore hypothesized that we could define molecular correlates to predict response to EGFR inhibition.

Methods: Correlative tumor samples derived from a phase II trial of neoadjuvant erlotinib in muscle invasive urothelial carcinoma of the bladder were analyzed to define molecular determinants of response to EGFR inhibition. The effect of silencing a candidate molecular predictor of resistance to EGFR inhibition, HRAS, was assessed by changes in the IC50 of T24 cells (harbor mutant HRAS) expressing short hairpin RNAs to HRAS or a control shRNA.

Results: Analysis of the gene expression profiles of TURB-T (pretreatment) samples show that tumors from non-pT0 patients had significantly elevated levels of HRAS relative to tumors from pT0 patients. Furthermore, knock-down of HRAS in T24 cells enhanced the sensitivity of these cells to erlotinib.

Conclusions: Elevated HRAS expression is correlated with a lack of response to erlotinib in vivo and silencing of HRAS in T24 cells results in enhanced sensitivity to erlotinib in vitro. Further molecular analyses are ongoing.

No significant financial relationships to disclose.

Risk-specific intensity of surveillance practices in non-muscle-invasive bladder cancer: Results from the BCAN/SUO/AUA/LUGPA electronic survey

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Background: The ideal surveillance regimen for patients with non-muscle-invasive bladder cancer (NMIBC) is uncertain. Given different grade- and stage-specific risks of recurrence and progression, there is some question whether it might be acceptable to pursue less intensive surveillance practices for patients with lower risk disease, and there is a paucity of data on current patterns of care in this area of practice.

Methods: An electronic survey was developed by the Bladder Cancer Advocacy Network (BCAN) to elicit self-reported practices of cystoscopy, cytology, and radiographic testing in the setting of surveillance for patients with a history of NMIBC. The survey was circulated to urologists via the AUA, SUO and LUGPA distribution lists. 512 respondents completed the survey.

Results: Among respondents, 66% report performing cystoscopy every 3 months on all patients for at least the first two years following diagnosis of NMIBC. The remaining 33% report performing surveillance cystoscopy less frequently, 95% of whom report doing so in the setting of low grade pathology. Similarly, 51% report using cytology with every cystoscopy, 23% do so for all high grade cases, and 30% report not using cytology with every cystoscopy. In the absence of recurrence for patients with an initial high grade diagnosis, upper tract reimaging is performed annually in 48%, biannually in 37% and never in 3%. The corresponding figures for patients with an index diagnosis of low grade disease are 14%, 37% and 28%, respectively. In the event of a recurrence in the bladder, 80% of respondents report reimaging the upper tracts for patients with high grade disease, versus 45% in the event of a low grade recurrence.

Conclusions: A substantial number of urologists responding to a survey report using relatively less intensive surveillance practices in patients with lower risk NMIBC. These results suggest a lack of consensus on the ideal intensity of evaluation in this setting, and provide a basis for prospective studies to validate the safest and most cost-effective strategies for surveillance.

No significant financial relationships to disclose.

Patterns of utilization of urine-based markers in non-muscle-invasive bladder cancer: Results from the BCAN/SUO/AUA/LUGPA electronic survey

261

Background: In addition to cytologic evaluation, there are currently four urine-based tests approved by the FDA for bladder cancer detection. At this point, the Guidelines panels from the AUA and EAU do not make specific recommendations about the ideal role of these tests. Furthermore, there is a paucity of data on current patterns of care in this area of practice.

Methods: An electronic survey was developed by the Bladder Cancer Advocacy Network (BCAN) to elicit self-reported practices of the use of cytology and urine-based markers in the settings of general use, surveillance, and assessment of response after intravesical therapy for patients with NMIBC. The survey was circulated to urologists via the AUA, SUO and LUGPA distribution lists. 512 respondents completed the survey.

Results: Among all respondents, 93% report sending cytology routinely (25% via barbotage) in general use. In contrast, 37% report using NMP22 in this setting, 54% report using FISH, and 32% (45% of SUO respondents vs. 31% of AUA respondents, p=0.04) responded that there is “no role for urine-based markers in this setting.” Similar proportions were reported in the specific settings of routine surveillance and post-BCG assessment. When presented with the vignette of a positive marker test and negative cytology and cystoscopy, 36% chose to proceed to the OR for biopsy, 37% chose to repeat cystoscopy and cytology in 3 months, 21% chose “no role for markers in this setting” and 13% chose “other.”

Conclusions: In the absence of more specific guidance, the results of this survey suggest considerable variation in the use and interpretation of urine-based markers in NMIBC. FISH is the marker reported to be used most commonly in multiple settings, however 31-45% of respondents report “no role” for any of the tests in their practice. Greater than one out of three respondents reported taking patients for biopsy under anesthesia in the setting of an isolated positive marker. These preliminary data underscore the need for prospective studies to validate the optimal role of urine-based markers in the setting of NMIBC.

No significant financial relationships to disclose.

Recurrence and survival following preoperative sorafenib for advanced renal cell carcinoma

384

Background: The impact of neoadjuvant or preoperative therapy in the setting of advanced renal cell carcinoma on recurrence-free or survival outcomes is not known.

Methods: 28 patients with renal cell carcinoma were treated with preoperative sorafenib in a prospective pilot study (LCCC 0603). Patient files were reviewed a median of 885 days (2.42 years) following nephrectomy. Records were evaluated for 13 patients with nonmetastatic disease for development of recurrence, and for 15 patients with stage IV disease for survival.

Results: For the nonmetastatic patients, only 2 patients had developed recurrent disease, one underwent metastectomy and remains in surveillance and the other is on second line systemic targeted therapy. A median recurrence-free survival has not been met after a median 2.5 years. For stage IV disease patients at a median follow up of 2.3 years, a median survival has also not been reached. Four patients are deceased, one patient is lost to follow up, and 10 remain alive. Treatments for metastatic disease included continued sorafenib, high dose interleukin-2, sunitinib, pazopanib, temsirolimus, and everolimus. Some stage IV patients have also enjoyed prolonged treatment-free intervals ranging from six months to over two years, with biopsy confirmed, but indolent disease.

Conclusions: Although these data are descriptive, these observations are suggestive that preoperative therapy with sorafenib is unlikely to accelerate the growth of grossly metastatic or micrometastatic disease. Further studies are needed to determine whether preoperative therapy is valuable in improving recurrence-free or overall survival endpoints.

[Table: see text]

Reported patterns of utilization of intravesical therapy in non-muscle-invasive bladder cancer: Results from the BCAN/SUO/AUA/LUGPA electronic survey

267

Background: Guidelines recommend intravesical chemotherapy and immunotherapy in the management of non-muscle-invasive bladder cancer (NMIBC) to reduce the risks of recurrence and potentially progression. Nevertheless, recent claims-based analyses have suggested exceedingly low rates of utilization of some of these therapies in practice. In general, there is a paucity of data to inform our understanding of current patterns of care.

Methods: An electronic survey was developed by the Bladder Cancer Advocacy Network (BCAN) to elicit self-reported practices of utilization of intravesical chemo- and immuno-therapy for patients with NMIBC. The survey was circulated to urologists via the AUA, SUO and LUGPA distribution lists. 512 respondents completed the survey.

Results: Overall, 63% of respondents reported routine administration of perioperative mitomycin-c (MMC) after TURBT [80% of SUO respondents vs. 55% of AUA/LUGPA respondents (p<0.001)]. Whereas 5% of respondents reported routine induction therapy with all new low-grade (LG) diagnoses, 99% reported routinely doing so in new high-grade (HG) cases; most commonly with single- agent BCG (94%; vs. 9% BCG/IFN and 5% MMC). Reported induction therapy was higher in the setting of high-volume (77%) or frequently recurrent LG (44%) disease. 89% reported routinely using maintenance therapy for HG, vs. 29% for LG. Reduced strength BCG was most commonly endorsed only in the settings of poor tolerance of full strength (84%) or maintenance (11%), with only 3% endorsing routine use. Routine post-BCG biopsy, even with normal cystoscopy, was endorsed by 28% of respondents, and 64% of respondents used urine-based markers to assess response to intravesical therapy.

Conclusions: Urologists report grade-specific patterns of utilization of intravesical therapy for NMIBC, at rates higher than suggested in some claims-based analyses. Variation exists in post-treatment followup practices. Further study is needed to rectify these self-reported patterns of care with results from claims-based analyses.

No significant financial relationships to disclose.

Oncologic outcomes for node-positive patients undergoing robotic radical cystectomy

290

Background: Previous studies have shown robot assisted radical cystectomy (RARC) to have equivalent perioperative outcomes to open radical cystectomy. There are few reports that have examined the oncologic results of RARC specifically with respect to node-positive patients. We report the outcomes of node-positive patients who have undergone RARC with medium-term (at least 1 year) follow-up.

Methods: A total of 275 patients underwent RARC at two institutions for invasive bladder cancer between 2005-present. We examined the 50 patients with node-positive disease that had a minimum of one year follow-up. Oncologic outcomes, recurrence free survival (RFS), and disease specific survival (DSS) were analyzed and compared to the open literature.

Results: Mean clinical follow up in this case series was 29 months (range 12–64 months). The mean number of lymph nodes removed was 18 (range 5–35), and mean number of positive LNs was 3.1 (range 1–12). Overall rate of LN positivity was 26%. Mean LN density was 18%. Seventeen (34%) patients had ≤ pT2 disease and 33 (66%) pT3/T4 disease. At this follow-up, 29 patients have recurred, 21 patients died of disease, giving a RFS and DSS of 42% and 58%, respectively. Mean (median) time to recurrence was 10.2 months (9 months). A total of 60% of patients received peri-operative chemotherapy in this cohort. These findings are consistent with prior reports of such oncologic outcomes in node-positive patients in open series.

Conclusions: The oncologic follow-up of patients undergoing RARC with LN positive disease appears to have acceptable outcomes during medium term (mean 29 months) follow-up. As our follow-up increases, we expect to continue to accurately define the long-term clinical suitability and oncologic success of this procedure in this high-risk population.

No significant financial relationships to disclose.

Robotic radical cystectomy: Medium-term oncologic follow-up

288

Background: We report our experience with robot assisted radical cystectomy (RARC) with regard to medium-term (at least 2 year) oncologic outcomes.

Methods: A total of 275 patients have undergone RARC and urinary diversion at two institutions for invasive bladder cancer between 2005-present. We performed a retrospective analysis of the 139 patients who underwent RARC with a minimum of 2 years follow-up. Medium term oncologic outcomes including recurrence rates, time to recurrence, recurrence free survival (RFS), disease specific survival (DSS) were analyzed. Follow-up was measured from time of surgery to time of most recent clinical follow-up.

Results: This cohort of patients consisted of 108 men (78%) and 31 women (22%) at a mean age of 67.3 years (range 45-86 years). Sixty-one (44%) patients had ≤ pT2 disease, 38 (27%) pT3/T4 disease, and 40 (29%) N+ disease. The mean number of lymph nodes removed was 18 (range 3-41). The average clinical follow up in this case series was nearly 3 years with a mean of 35.9 months (range 24-64 months). At this follow-up, 39 patients have recurred, 27 patients died of disease, and 5 patients died of other causes giving an overall RFS, DSS, and OS rates of 80%, 71%, and 68%, respectively. The mean (median) time to recurrence was 12.3 months (10 months). These findings are consistent with prior reports of the oncologic outcomes for open radical cystectomy.

Conclusions: The oncologic follow-up of patients undergoing RARC appears to be favorable with acceptable outcomes in the medium-term (mean – 3 years). As our follow-up increases, we should expect to truly define the long-term clinical appropriateness and oncologic success of this procedure.

No significant financial relationships to disclose.

Ror2, a developmentally regulated kinase, promotes tumor growth potential in renal cell carcinoma

Inappropriate kinase expression and subsequent promiscuous activity defines the transformation of many solid tumors including renal cell carcinoma (RCC). Thus, the expression of novel tumor-associated kinases has the potential to dramatically shape tumor cell behavior. Further, identifying tumor-associated kinases can lend insight into patterns of tumor growth and characteristics. Here, we report the identification of the RTK-like orphan receptor 2 (Ror2), a new tumor-associated kinase in RCC cell lines and primary tumors. Ror2 is an orphan receptor tyrosine kinase with physiological expression normally seen in the embryonic kidney. However, in RCC, Ror2 expression correlated with expression of genes involved at the extracellular matrix, including Twist and matrix metalloprotease-2 (MMP2). Expression of MMP2 in RCC cells was suppressed by Ror2 knockdown, placing Ror2 as a mediator of MMP2 regulation in RCC and a potential regulator of extracellular matrix remodeling. The suppression of Ror2 not only inhibited cell migration, but also inhibited anchorage-independent growth in soft agar and growth in an orthotopic xenograft model. These findings suggest a novel pathway of tumor-promoting activity by Ror2 within a subset of renal carcinomas, with significant implications for unraveling the tumorigenesis of RCC.

Trisomy 13 in patients with hematological malignancies

7055

Introduction: Cytogenetic abnormalities have been shown to be the most important determinant of prognosis in patients with acute myeloid leukemia (AML). In AML, trisomy 13 has been placed in the intermediate prognostic category although recent reports associate it with a more dismal outcome. The number of cases reported in the literature are relatively few, we reviewed our experience with trisomy 13 in hematologic malignancies to determine its significance and prognosis. Methods: We conducted a clinicopathological review of cases seen in our institution from January of 1990 to October of 2006. Our cytogenetic records were searched for patients, who had a hematological disorder whose non-stimulated bone marrow karyotype was found to have trisomy 13 as a sole abnormality. In men the absence of the Y chromosome was not regarded as a separate abnormality. Results: A total of 27 patients were identified. The median age was 76 years (range 25–87), 22/27 were male. The number of cases and diseases identified were 15 with AML, 5 with a myelodysplastic syndrome, 4 with an uncategorized myelodysplastic/myeloproliferative disorder, 2 with acute lymphoblastic leukemia and 1 with a chronic myeloproliferative disorder. Of the AML group 7 were M0 according to the FAB classification, 2 patients were identified to have M4 and another two M2. A single case each of M1 and M6 was also identified. In these 15 patients, 9 underwent induction chemotherapy, which consisted of intermediate dose Ara-C in 3 cases, anthracycline plus Ara-C in 5 patients, and daunorubicin, vincristine and prednisone in 1. Another 3 patients were given palliative treatment. For the rest of the subjects the type of treatment was unknown. A CR was obtained in 6 patients, 1 patient underwent a myeloablative stem cell transplant. Death has occurred in 24 patients, the median survival of the entire group was 5.4 months. In the patients with AML the median survival was 4.7 months, of the patients who achieved a CR the median survival was 9.5 months. Conclusions: We describe one of the largest series reported to date of trisomy 13 in hematologic malignancies and found that trisomy 13 is associated with male gender and an older age at presentation, as well as a poor prognosis. In AML its presence is associated with an FAB-M0 phenotype and its occurrence should be regarded as a high-risk feature.

No significant financial relationships to disclose.

Testicular teratoma with a unique mode of spread and spontaneous maturation

Chylous ascites, a rare compliation following retroperitoneal lymph node dissection, has not been reported as a means of spread of testicular cancer. This report describes a unique path of spread of testicular cancer which also appears to spontaneously mature at the metastatic site.

Primary thyroidlike carcinoma of the kidney

We present a unique papillary thyroidlike carcinoma of the kidney. The patient had an incidentally discovered renal mass that, histologically and immunohistochemically, resembled papillary thyroid carcinoma. Workup revealed no primary site other than the kidney and no evidence of metastasis. This is the first reported case of a malignant papillary thyroidlike cancer of the kidney.

Differences in the time course of dopaminergic supersensitivity following chronic administration of haloperidol, molindone, or sulpiride

The onset and persistence of changes in 3H-spiroperidol binding to dopamine (DA) D2 receptors were examined in rat mesolimbic and striatal brain regions following daily administration of haloperidol, molindone, or sulpiride for 3, 7, 14, or 28 days. Neuroleptic dose equivalencies were determined by inhibition of 3H-spiroperidol in vivo binding in several rat brain regions. Changes in locomotor and stereotyped responses to the specific DA D2 agonist quinpirole were examined 3 days after the last treatment dose. Haloperidol or molindone administration increased mean stereotypy scores and striatal DA D2 receptor densities throughout the 28-day treatment period. In contrast, mesolimbic DA D2 receptor densities were transiently increased and returned to control values, after 28 days of haloperidol or molindone treatment. Sulpiride treatment increased mean stereotypy scores and striatal Bmax values, but had no effect on locomotion or mesolimbic dopamine receptor density. Additionally, the magnitude of change in the various measures of brain DA function varied among the three neuroleptic treatment groups. Results from this study suggest that mesolimbic and striatal brain regions differ in their response to long-term neuroleptic administration and that drug choice may influence the magnitude of neuroleptic-induced dopaminergic supersensitivity.

Mesolimbic dopamine receptor increases two weeks following hippocampal kindling

Kindled seizures developed in rats following repeated electrical stimulation of the left CA1 region of the hippocampus. Two weeks after the final kindled seizure, the densities of dopamine (DA) D2 receptors were assayed in the left and right amygdaloid area, nucleus accumbens, and nucleus caudatus. A significant increase (107%) in the density of DA D2-receptors in the ipsilateral nucleus accumbens occurred. This finding may help to define the long-term neurochemical consequences of kindling.