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1.  Renal Functional Outcomes after Robotic Multiplex Partial Nephrectomy: The National Cancer Institute Experience with Robotic Partial Nephrectomy for 3 or more Tumors in a Single Kidney 
International urology and nephrology  2016;48(11):1817-1821.
PMCID: PMC5090974  PMID: 27515314
Kidney Cancer; Partial Nephrectomy; Robotic Surgery; Multiplex Partial Nephrectomy; Multifocal Renal Tumors
2.  The FNIP co-chaperones decelerate the Hsp90 chaperone cycle and enhance drug binding 
Nature Communications  2016;7:12037.
Heat shock protein-90 (Hsp90) is an essential molecular chaperone in eukaryotes involved in maintaining the stability and activity of numerous signalling proteins, also known as clients. Hsp90 ATPase activity is essential for its chaperone function and it is regulated by co-chaperones. Here we show that the tumour suppressor FLCN is an Hsp90 client protein and its binding partners FNIP1/FNIP2 function as co-chaperones. FNIPs decelerate the chaperone cycle, facilitating FLCN interaction with Hsp90, consequently ensuring FLCN stability. FNIPs compete with the activating co-chaperone Aha1 for binding to Hsp90, thereby providing a reciprocal regulatory mechanism for chaperoning of client proteins. Lastly, downregulation of FNIPs desensitizes cancer cells to Hsp90 inhibitors, whereas FNIPs overexpression in renal tumours compared with adjacent normal tissues correlates with enhanced binding of Hsp90 to its inhibitors. Our findings suggest that FNIPs expression can potentially serve as a predictive indicator of tumour response to Hsp90 inhibitors.
Hsp90 is required for the folding, stability and activity of several drivers of oncogenesis. Here the authors show that Folliculin-interacting proteins (FNIP) 1 and 2, whose expression correlates with the cellular response to Hsp90 inhibitors, are co-chaperones of Hsp90 that function by inhibiting its ATPase activity.
PMCID: PMC4931344  PMID: 27353360
3.  Mps1 Mediated Phosphorylation of Hsp90 Confers Renal Cell Carcinoma Sensitivity and Selectivity to Hsp90 Inhibitors 
Cell reports  2016;14(4):872-884.
The molecular chaperone Hsp90 protects deregulated signaling proteins that are vital for tumor growth and survival. Tumors generally display sensitivity and selectivity toward Hsp90 inhibitors; however, the molecular mechanism underlying this phenotype remains undefined. We report that the mitotic checkpoint kinase Mps1 phosphorylates a conserved threonine residue in the amino-domain of Hsp90. This, in turn, regulates chaperone function by reducing Hsp90 ATPase activity while fostering Hsp90 association with kinase clients, including Mps1. Phosphorylation of Hsp90 is also essential for the mitotic checkpoint because it confers Mps1 stability and activity. We identified Cdc14 as the phosphatase that dephosphorylates Hsp90 and disrupts its interaction with Mps1. This causes Mps1 degradation, thus providing a mechanism for its inactivation. Finally, Hsp90 phosphorylation sensitizes cells to its inhibitors, and elevated Mps1 levels confer renal cell carcinoma selectivity to Hsp90 drugs. Mps1 expression level can potentially serve as a predictive indicator of tumor response to Hsp90 inhibitors.
Graphical abstract
PMCID: PMC4887101  PMID: 26804907
4.  An Unusual Etiology of Urinary Retention – Small Cell Prostate Carcinoma 
Urology Case Reports  2016;7:53-54.
We report the case of a 63-year-old male who presented with painless gross hematuria and urinary retention. Pathology obtained from transurethral resection of the prostate revealed pure small cell carcinoma of the prostate. Metastatic evaluation confirmed stage IV disease with lymphatic and hepatic metastasis. Despite aggressive systemic chemotherapy, the patient succumbed to his disease eleven months after initial diagnosis. Small cell carcinoma is an aggressive variant of prostate cancer that often presents late in the clinical course. We review the literature and discuss the clinical features associated with this rare subset of prostate cancer.
PMCID: PMC4909518  PMID: 27335794
Neuroendocrine tumors; Prostatic carcinoma; Urinary retention
5.  Sixth BHD Symposium and First International Upstate Kidney Cancer Symposium: latest scientific and clinical discoveries 
Oncotarget  2016;7(13):15292-15298.
The Sixth BHD Symposium and First International Upstate Kidney Cancer Symposium concluded in September 2015, in Syracuse, NY, USA. The program highlighted recent findings in a variety of areas, including drug development, therapeutics and surgical management of patients with BHD and multi-focal renal tumors, as well as multidisciplinary approaches for patients with localized, locally advanced and metastatic renal cell carcinoma.
PMCID: PMC4941241  PMID: 26933819
FLCN; Birt-Hogg-Dubé syndrome; renal cell carcinoma; clear cell renal cell carcinoma
6.  c-Abl Mediated Tyrosine Phosphorylation of Aha1 Activates Its Co-chaperone Function in Cancer Cells 
Cell reports  2015;12(6):1006-1018.
The ability of Heat Shock Protein 90 (Hsp90) to hydrolyze ATP is essential for its chaperone function. The co-chaperone Aha1 stimulates Hsp90 ATPase activity, tailoring the chaperone function to specific “client” proteins. The intracellular signaling mechanisms directly regulating Aha1 association with Hsp90 remain unknown. Here, we show that c-Abl kinase phosphorylates Y223 in human Aha1 (hAha1), promoting its interaction with Hsp90. This, consequently, results in an increased Hsp90 ATPase activity, enhances Hsp90 interaction with kinase clients, and compromises the chaperoning of non-kinase clients such as glucocorticoid receptor and CFTR. Suggesting a regulatory paradigm, we also find that Y223 phosphorylation leads to ubiquitination and degradation of hAha1 in the proteasome. Finally, pharmacologic inhibition of c-Abl prevents hAha1 interaction with Hsp90, thereby hypersensitizing cancer cells to Hsp90 inhibitors both in vitro and ex vivo.
Graphical abstract
PMCID: PMC4778718  PMID: 26235616
The Journal of urology  2011;185(5):1589-1590.
PMCID: PMC4731868  PMID: 21419442
8.  Impact of pathological tumour characteristics in patients with sarcomatoid renal cell carcinoma 
BJU international  2012;109(11):1600-1606.
Patients with sarcomatoid renal cell carcinoma (sRCC) are known to have poor prognosis and response to systemic therapy.
We set out to examine the influence of pathological tumour characteristics on survival to aid prognostication and clinical trial design.
A single-centre database was reviewed to identify all patients with sRCC.
Clinical variables and pathological information, including histology, necrosis, percentage of sarcomatoid features (PSF) and microvascular invasion (MVI), were recorded and correlated to outcome.
Analyses of 104 patients with sRCC found that the median (range) size of tumours was 9.5 cm (2.5–30), 65% of patients had areas of clear cell histology, and 69.2% had metastatic disease at presentation.
The PSF did not influence tumour size, stage, necrosis, MVI, nodes or metastasis.
A total of 85 patients (81.7%) died during the follow-up period with a median (95% confidence interval [CI]) survival of 5.9 months (4.7–8.9).
In the overall cohort, Eastern Cooperative Group performance status (ECOGPS), tumour size and metastatic disease were independent predictors of poor survival. MVI, PSF and percentage necrosis were strongly associated with outcome but were not independent predictors of outcome.
A multivariate risk model was established that incorporated six covariates (tumour size, MVI, ECOGPS, PSF, necrosis, and metastatic disease) to produce a predictive tool.
Both patients with localized and metastatic sRCC have very poor survival outcomes.
Pathological features MVI, PSF and necrosis are important predictors of survival and could be used in a prognostic model while grade and histology do not influence prognosis.
A prognostic model, if validated, could aid in patient counselling and/or clinical trial design.
PMCID: PMC4676716  PMID: 22221668
sarcomatoid; kidney cancer; adjuvant; prognosis; RCC
9.  Defining the radiobiology of prostate cancer progression: An important question in translational prostate cancer research 
Prostate cancer is one of the most common malignancies affecting men worldwide. High mortality rates from advanced and metastatic prostate cancer in the United States are contrasted by a relatively indolent course in the majority of cases. This gives hope for finding methods that could direct personalized diagnostic, preventative, and treatment approaches to patients with prostate cancer. Recent advances in multiparametric magnetic resonance imaging (MP-MRI) offer a noninvasive diagnostic intervention which allows correlation of prostate tumor image characteristics with underlying biologic evidence of tumor progression. The power of MP-MRI includes examination of both local invasion and nodal disease and might overcome the challenges of analyzing the multifocal nature of prostate cancer. Future directions include a careful analysis of the genomic signature of individual prostatic lesions utilizing image-guided biopsies. This review examines the diagnostic potential of MRI in prostate cancer.
PMCID: PMC4478242  PMID: 24879423
Prostate cancer; magnetic resonance imaging; lymph node imaging; image-guided biopsy; radiobiology
10.  The dynamic interactome of human Aha1 upon Y223 phosphorylation 
Data in Brief  2015;5:752-755.
Heat Shock Protein 90 (Hsp90) is an essential chaperone that supports the function of a wide range of signaling molecules. Hsp90 binds to a suite of co-chaperone proteins that regulate Hsp90 function through alteration of intrinsic ATPase activity. Several studies have determined Aha1 to be an important co-chaperone whose binding to Hsp90 is modulated by phosphorylation, acetylation and SUMOylation of Hsp90 [1], [2]. In this study, we applied quantitative affinity-purification mass spectrometry (AP-MS) proteomics to understand how phosphorylation of hAha1 at Y223 altered global client/co-chaperone interaction [3]. Specifically, we characterized and compared the interactomes of Aha1–Y223F (phospho-mutant form) and Aha1–Y223E (phospho-mimic form). We identified 99 statistically significant interactors of hAha1, a high proportion of which (84%) demonstrated preferential binding to the phospho-mimic form of hAha1.
The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium ( via the PRIDE partner repository [4] with the dataset identifier PXD001737.
PMCID: PMC4659802  PMID: 26693507
Cancer; Hsp90; Interactome; Proteomics; Phosphorylation; Chaperones; Aha1; Co-chaperones
11.  Routine adrenalectomy for renal cancer: an antiquated practice 
Nature reviews. Urology  2011;8(10):534-536.
PMCID: PMC4440789  PMID: 21931345
12.  Loss of Wave1 gene defines a subtype of lethal prostate cancer 
Oncotarget  2015;6(14):12383-12391.
Genetic alterations involving TMPRSS2-ERG alterations and deletion of key tumor suppressor genes are associated with development and progression of prostate cancer (PCa). However, less defined are early events that may contribute to the development of high-risk metastatic prostate cancer. Bioinformatic analysis of existing tumor genomic data from PCa patients revealed that WAVE complex gene alterations are associated with a greater likelihood of prostate cancer recurrence. Further analysis of primary vs. castration resistant prostate cancer indicate that disruption of WAVE complex gene expression, and particularly WAVE1 gene (WASF1) loss, is also associated with castration resistance, where WASF1 is frequently co-deleted with PTEN and resists androgen deprivation therapy (ADT). Hence, we propose that WASF1 status defines a subtype of ADT-resistant patients. Better understanding of the effects of WAVE pathway disruption will lead to development of better diagnostic and treatment modalities.
PMCID: PMC4494945  PMID: 25906751
WAVE; prostate cancer; genomics; androgen receptor; castration resistance
13.  Adrenal Nodular Hyperplasia in Hereditary Leiomyomatosis and Renal Cell Cancer 
The Journal of urology  2012;189(2):430-435.
Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is characterized by cutaneous leiomyomas, uterine fibroids, and aggressive papillary renal cell carcinoma (RCC). A number of our HLRCC patients were found to have atypical adrenal nodules and which were further evaluated to determine if these adrenal nodules were associated with HLRCC.
HLRCC patients underwent a comprehensive clinical and genetic evaluation. Clinical presentation, anatomic and functional imaging, endocrine evaluation, pathologic examination and the results from germline mutation testing were reviewed.
Twenty of 255 HLRCC patients (7.8%) were found to have primary adrenal lesions. Among these, three were found to have bilateral adrenal lesions and four were found to have multiple nodules. Two patients had ACTH-independent hypercortisolism. A total of 27 adrenal lesions were evaluated. The imaging characteristics of five (18.5%) of these lesions were not consistent with adenoma by non-contrast CT criteria. PET imaging was positive in 7 of 10 cases (70%). Twelve nodules were surgically resected from ten adrenal glands. Pathologic examination revealed macronodular adrenal hyperplasia in all specimens.
Unilateral and bilateral adrenal nodular hyperplasia was detected in a subset of patients affected with HLRCC. A functional endocrine evaluation is recommended when an adrenal lesion is discovered. Imaging frequently demonstrates lesions that are not typical of adenomas and PET imaging may be positive. To date, no patient has been found to have adrenal malignancy and active surveillance of HLRCC adrenal nodules appears justified.
PMCID: PMC4435969  PMID: 22982371
HLRCC; kidney cancer; adrenal nodule; fumarate hydratase
14.  Targeting Hsp90 in urothelial carcinoma 
Oncotarget  2015;6(11):8454-8473.
Urothelial carcinoma, or transitional cell carcinoma, is the most common urologic malignancy that carries significant morbidity, mortality, recurrence risk and associated health care costs. Despite use of current chemotherapies and immunotherapies, long-term remission in patients with muscle-invasive or metastatic disease remains low, and disease recurrence is common. The molecular chaperone Heat Shock Protein-90 (Hsp90) may offer an ideal treatment target, as it is a critical signaling hub in urothelial carcinoma pathogenesis and potentiates chemoradiation. Preclinical testing with Hsp90 inhibitors has demonstrated reduced proliferation, enhanced apoptosis and synergism with chemotherapies and radiation. Despite promising preclinical data, clinical trials utilizing Hsp90 inhibitors for other malignancies had modest efficacy. Therefore, we propose that Hsp90 inhibition would best serve as an adjuvant treatment in advanced muscle-invasive or metastatic bladder cancers to potentiate other therapies. An overview of bladder cancer biology, current treatments, molecular targeted therapies, and the role for Hsp90 inhibitors in the treatment of urothelial carcinoma is the focus of this review.
PMCID: PMC4496161  PMID: 25909217
urothelial carcinoma; pathogenesis; bladder cancer treatments; heat shock protein-90; Hsp90 inhibitors
15.  Perioperative, Functional, and Oncologic Outcomes of Partial Adrenalectomy for Multiple Ipsilateral Pheochromocytomas 
Journal of Endourology  2014;28(1):112-116.
Objective: Managing patients with multiple adrenal masses is technically challenging. We present our experience with minimally invasive partial adrenalectomy (PA) performed for synchronous multiple ipsilateral pheochromocytomas in a single setting.
Materials and Methods: We reviewed records of patients undergoing PA for pheochromocytoma at the National Cancer Institute between 1994 and 2010. Patients were included if multiple tumors were excised from the ipsilateral adrenal gland in the same operative setting. Perioperative, functional, and oncologic outcomes of PA for multiple pheochromocytomas are shown.
Results: Of 121 partial adrenalectomies performed, 10 procedures performed in eight patients for synchronous multiple ipsilateral pheochromocytomas were identified. All eight patients were symptomatic at presentation. The mean patient age was 30.6 years, median follow up was 12 months. The average surgical time was 228 minutes, average blood loss of 125 mL, and average number of tumors removed was 2.6 per adrenal. In total, 26 tumors were removed, 24 were pathologically confirmed pheochromocytomas, while two were adrenal cortical hyperplasia. After surgery, all patients had resolution of their symptoms, one patient required steroid replacement postoperatively. On postoperative imaging, one patient had evidence of ipsilateral adrenal nodule at the prior resection site 2 months postoperatively, which was consistent with incomplete resection.
Conclusions: Minimally invasive surgical resection of synchronous multiple pheochromocytomas is feasible with acceptable perioperative, functional, and short-term oncologic outcomes.
PMCID: PMC3880898  PMID: 23998199
16.  To resect or not to resect? That is the question 
Gut  2010;60(9):1177-1235.
PMCID: PMC4070298  PMID: 20965874
17.  Molecular mechanisms of tissue inhibitor of metalloproteinase 2 in the tumor microenvironment 
There has been a recent paradigm shift in the way we target cancer, drawing a greater focus on the role of the tumor microenvironment (TME) in cancer development, progression and metastasis. Within the TME, there is a crosstalk in signaling and communication between the malignant cells and the surrounding extracellular matrix. Matrix metalloproteinases (MMPs) are zinc-dependent endoproteases that have the ability to degrade the matrix surrounding a tumor and mediate tumor growth, angiogenesis and metastatic disease. Their endogenous inhibitors, the Tissue Inhibitors of Metalloproteinases (TIMPs), primarily function to prevent degradation of the ECM via inhibition of MMPs. However, recent studies demonstrate that TIMP family members also possess MMP-independent functions. One TIMP member in particular, TIMP-2, has many distinct properties and functions, that occur independent of MMP inhibition, including the inhibition of tumor growth and reduction of angiogenesis through decreased endothelial cell proliferation and migration. The MMP-independent molecular mechanisms and signaling pathways elicited by TIMP-2 in the TME are described in this review.
PMCID: PMC4452049  PMID: 26056585
Tissue inhibitor of metalloproteinase-2 (TIMP-2); Matrix metalloproteinase (MMPs); Tumor microenvironment (TME); Angiogenesis
18.  Familial testicular germ cell tumor: no associated syndromic pattern identified 
Testicular germ cell tumor (TGCT) is the most common malignancy in young men. Familial clustering, epidemiologic evidence of increased risk with family or personal history, and the association of TGCT with genitourinary (GU) tract anomalies have suggested an underlying genetic predisposition. Linkage data have not identified a rare, highly-penetrant, single gene in familial TGCT (FTGCT) cases. Based on its association with congenital GU tract anomalies and suggestions that there is an intrauterine origin to TGCT, we hypothesized the existence of unrecognized dysmorphic features in FTGCT.
We evaluated 38 FTGCT individuals and 41 first-degree relatives from 22 multiple-case families with detailed dysmorphology examinations, physician-based medical history and physical examination, laboratory testing, and genitourinary imaging studies.
The prevalence of major abnormalities and minor variants did not significantly differ between either FTGCT individuals or their first-degree relatives when compared with normal population controls, except for tall stature, macrocephaly, flat midface, and retro-/micrognathia. However, these four traits were not manifest as a constellation of features in any one individual or family. We did detect an excess prevalence of the genitourinary anomalies cryptorchidism and congenital inguinal hernia in our population, as previously described in sporadic TGCT, but no congenital renal, retroperitoneal or mediastinal anomalies were detected.
Overall, our study did not identify a constellation of dysmorphic features in FTGCT individuals, which is consistent with results of genetic studies suggesting that multiple low-penetrance genes are likely responsible for FTGCT susceptibility.
PMCID: PMC3937045  PMID: 24559313
Familial testicular cancer; Dysmorphology; Developmental anomalies
19.  Feasibility and Outcomes of Laparoscopic Renal Intervention After Prior Open Ipsilateral Retroperitoneal Surgery 
Journal of Endourology  2013;27(2):196-201.
Background and Purpose
Treating patients with renal-cell carcinoma (RCC) after previous retroperitoneal surgery (renal or adrenal) is technically challenging. We present our initial experience with laparoscopic renal interventions (LRI) after previousopen retroperitoneal surgery in patients needing ipsilateral renal intervention. We report on feasibility, functional and oncologic outcomes of LRI after previous open retroperitoneal surgery.
Patients and Methods
We reviewed records of patients undergoing attempted laparoscopic or robot-assisted renal intervention after at least one previous open ipsilateral retroperitoneal surgery. We identified 34 patients who underwent 39 staged attempted LRI after 48 previous open ipsilateral renal or adrenal surgeries. The LRI included 20 minimally invasive partial nephrectomies (MIPN), 11 laparoscopic radiofrequency ablations (LRFA), and 8 laparoscopic nephrectomies (LTN). Demographic, perioperative, renal functional, and oncologic outcome data were collected. Statistical analyses were performed to identify risks for conversion to open surgery.
No attempted nephron-sparing procedure resulted in kidney loss. Overall conversion rate of the cohort was 28% and was highest in the MIPN group (40%). On univariate analysis, only multiple tumors that were treated significantly increased chances of open conversion (P<0.01). Subset analysis demonstrated similar rates of blood loss, operative times, and conversion rates in patients undergoing partial nephrectomy having previous open partial nephrectomy compared with previous open adrenal surgery only. There was no significant difference in preservation of renal function between MIPN and LRFA, with more than 85% of preoperative renal function preserved. Mean follow-up of 11.9 months (range 1–97.5 mos) metastasis-free survival and overall survival was 94.1% and 97%, respectively.
LRI after previous open ipsilateral retroperitoneal surgery is feasible. Repeated partial nephrectomy has the highest conversion risks among the laparoscopic renal interventions and appears to be independent of previous renal or adrenal procedure. Attempting repeated LRI for multiple tumors is a significant risk factor for open conversion. Renal functional and oncologic outcomes are encouraging at early follow-up.
PMCID: PMC3573724  PMID: 22963658
20.  Robot-Assisted Laparoscopic Partial Nephrectomy for Tumors Greater than 4 cm and High Nephrometry Score: Feasibility, Renal Functional and Oncological Outcomes with Minimum 1 Year Follow-up 
Urologic oncology  2011;31(1):51-56.
Minimally invasive robotic assistance is being increasingly utilized to treat larger complex renal masses. We report on the technical feasibility and renal functional and oncological outcomes with minimum 1 year follow up of robot-assisted laparoscopic partial nephrectomy (RALPN) for tumors greater than 4 cm.
Methods and Materials
The urologic oncology database was queried to identify patients treated with RALPN for tumors greater than 4 cm and a minimum follow up of 12 months. We identified 19 RALPN on 17 patients treated between June 2007 and July 2009. Two patients underwent staged bilateral RALPN. Demographic, operative, and pathologic data were collected. Renal function was assessed by serum creatinine levels, estimated glomerular filtration rate and nuclear renal scans assessed at baseline, 3 and 12 months post-operatively. All tumors were assigned R.E.N.A.L. nephrometry scores (
The median nephrometry score for the largest tumor from each kidney was 9 (range 6–11) while the median size was 5 cm (range 4.1–15). Three of 19 cases (16%) required intraoperative conversion to open partial nephrectomy. No renal units were lost. There were no statistically significant differences between preoperative and postoperative creatinine and eGFR. A statistically significant decline of ipsilateral renal scan function (49% vs. 46.5%, p=0.006) was observed at three months and at twelve months postoperatively (49% vs. 45.5%, p=0.014). No patients had evidence of recurrence or metastatic disease at a median follow up of 22 months (range 12–36).
RALPN is feasible for renal tumors greater than 4 cm with moderate or high nephrometry scores. Although there was a modest decline in renal function of the operated unit, RALPN may afford the ability resect challenging tumors requiring complex renal reconstruction. The renal functional and oncological outcomes are promising at a median follow up of 22 months, but longer follow up is required.
PMCID: PMC3123423  PMID: 21292511
21.  Impact of Ischemia and Procurement Conditions on Gene Expression in Renal Cell Carcinoma 
Previous studies have shown that ischemia alters gene expression in normal and malignant tissues. There are no studies that evaluated effects of ischemia in renal tumors. This study examines the impact of ischemia and tissue procurement conditions on RNA integrity and gene expression in renal cell carcinoma.
Experimental Design
Ten renal tumors were resected without renal hilar clamping from 10 patients with renal clear cell carcinoma. Immediately after tumor resection, a piece of tumor was snap frozen. Remaining tumor samples were stored at 4C, 22C and 37C and frozen at 5, 30, 60, 120, and 240 minutes. Histopathologic evaluation was performed on all tissue samples, and only those with greater than 80% tumor were selected for further analysis. RNA integrity was confirmed by electropherograms and quantitated using RIN index. Altered gene expression was assessed by paired, two-sample t-test between the zero time point and aliquots from various conditions obtained from the same tumor.
One hundred and forty microarrays were performed. Some RNA degradation was observed 240 mins after resection at 37C. The expression of over 4,000 genes was significantly altered by ischemia times or storage conditions. The greatest gene expression changes were observed with longer ischemia time and warmer tissue procurement conditions.
RNA from kidney cancer remains intact for up to 4 hours post surgical resection regardless of storage conditions. Despite excellent RNA preservation, time after resection and procurement conditions significantly influence gene expression profiles. Meticulous attention to pre-acquisition variables is of paramount importance for accurate tumor profiling.
PMCID: PMC3658320  PMID: 23136194
Ischemia; gene expression microarrays; tissue procurement; renal cell carcinoma
22.  Succinate Dehydrogenase Kidney Cancer (SDH-RCC): An Aggressive Example of the Warburg Effect in Cancer 
The Journal of urology  2012;188(6):10.1016/j.juro.2012.08.030.
Recently, a new renal cell cancer (RCC) syndrome has been linked to germline mutation of multiple subunits (SDHB/C/D) of the Krebs cycle enzyme, succinate dehydrogenase. We report our experience with diagnosis, evaluation and treatment of this novel form of hereditary kidney cancer.
Materials and Methods
Patients with suspected hereditary kidney cancer were enrolled on an NCI-IRB approved protocol to study inherited forms of kidney cancer. Individuals from families with germline SDHB, SDHC and SDHD mutations and kidney cancer underwent comprehensive clinical and genetic evaluation.
Fourteen patients from twelve SDHB mutation families were evaluated. Patients presented with RCC at an early age, 33 yrs (range 15–62 yrs), four developed metastatic kidney cancer and some families were found to have no manifestations other than kidney tumors. An additional family with six individuals found to have clear cell RCC that presented at a young average age, 47 yrs (range 40–53yrs), was identified with a germline SDHC mutation (R133X), two of which developed metastatic disease. A patient with a history of carotid body paragangliomas and a very aggressive form of kidney cancer was evaluated from a family with germline SDHD mutation.
SDH-RCC can be an aggressive type of kidney cancer, especially in younger individuals. Although detection and management of early tumors is most often associated with good outcome, based on our initial experience with these patients and our long term experience with HLRCC, we recommend careful surveillance of patients at risk for SDH-RCC and wide surgical excision of renal tumors.
PMCID: PMC3856891  PMID: 23083876
renal cell cancer (RCC); hereditary kidney cancer; Krebs cycle; Succinate dehydrogenase
23.  Partial Adrenalectomy Minimizes the Need for Long-Term Hormone Replacement in Pediatric Patients with Pheochromocytoma and von Hippel-Lindau Syndrome 
Journal of pediatric surgery  2012;47(11):10.1016/j.jpedsurg.2012.07.003.
Children with von Hippel-Lindau syndrome are at an increased risk for developing bilateral pheochromocytomas. In an effort to illustrate the advantage of partial adrenalectomy (PA) over total adrenalectomy in children with VHL, we report the largest single series on PA for pediatric VHL patients, demonstrating a balance between tumor removal and preservation of adrenocortical function.
From 1994 to 2011, a prospectively maintained database was reviewed to evaluate 10 pediatric patients with hereditary pheochromocytoma for PA. Surgery was performed if there was clinical evidence of pheochromocytoma and normal adrenocortical tissue was evident on preoperative imaging and/or intraoperative ultrasonography. Perioperative data were collected and patients were followed for postoperative steroid use and tumor recurrence.
Ten pediatric patients with a diagnosis of VHL underwent 18 successful partial adrenalectomies (4 open, 14 laparoscopic). The median tumor size removed was 2.6 centimeters (range 1.2–6.5). Over a median follow up of 7.2 years (range 2.6–15.8) additional tumors in the ipsilateral adrenal gland were found in two patients. One patient underwent completion adrenalectomy and one underwent a salvage PA with resection of the ipsilateral lesion. One patient required short term steroid replacement therapy. At last follow up, 7 patients had no radiographic or laboratory evidence of pheochromocytoma.
At our institution, partial adrenalectomy is the preferred form of management for pheochromocytoma in the (VHL) pediatric population. This surgical approach allows for removal of tumor while preserving adrenocortical function and minimizing the side effects of long term steroid replacement on puberty and quality of life.
PMCID: PMC3846393  PMID: 23164001
adrenalectomy; partial adrenalectomy; pediatric VHL; pheochromocytoma
24.  Economic burden of reoperative renal surgery on solitary kidney: Do the ends justify the means? A cost effectiveness analysis 
The Journal of urology  2012;188(5):10.1016/j.juro.2012.07.029.
Despite the high morbidity of reoperative renal surgery (RRS) in patients with multifocal recurrent renal carcinoma, most patients are able to preserve adequate renal function to obviate the need for dialysis. The economic burden of RRS has not been evaluated. We aim to provide a cost-effectiveness analysis for patients requiring RRS on a solitary kidney.
Materials and Methods
We reviewed the charts of patients treated at the National Cancer Institute (NCI) requiring RRS from 1989 to 2010. Functional, oncological and surgical outcomes were evaluated, and the costs of RRS were calculated. We then compared the costs of a 33 patients cohort who underwent RRS on a solitary kidney and a hypothetical cohort of patients that would undergo uncomplicated nephrectomy, fistula placement and dialysis. All costs were calculated based on Medicare reimbursement rates derived from Current Procedural Terminology (CPT) codes. A cost-effectiveness analysis was applied.
Despite a high complication rate (45%), 87% of patients maintained adequate renal function to avoid dialysis and 96% remained metastasis free at an average follow up of 3.12 years (range 0.3-16.4). When compared to hypothetical dialysis cohort, the financial benefit of RRS was reached at 0.68 years.
RRS is a viable alternative for patients with multifocal renal cell carcinoma requiring multiple surgical interventions, especially when left with a solitary kidney. Despite the high complication rate, most patients are able to preserve renal function and have excellent oncological outcomes. The financial benefit of RRS is reached at less than 1 year.
PMCID: PMC3817487  PMID: 22998899
Reoperative renal surgery; repeat partial nephrectomy; cost effectiveness; nephron sparing surgery
25.  Outcomes of Patients with Surgically Treated Bilateral Renal Masses and a Minimum of 10 Years of Follow-Up 
The Journal of urology  2012;188(6):10.1016/j.juro.2012.08.038.
While nephron-sparing surgery has been advocated for patients with bilateral renal masses, the long-term functional and oncological outcomes are lacking.
To determine the outcomes of patients with bilateral renal masses (BRM) and a minimum of 10 years of follow-up.
Design, Setting, and Participants
Patients with BRM evaluated at the National Cancer Institute who underwent their initial surgical intervention at least 10 years ago and had interventions on both renal units were included in our analysis. The data collected included demographics, hereditary diagnosis, number of renal interventions, renal function, and mortality status.
Bilateral renal surgery.
Outcome Measurements and Statistical Analysis
Overal and RCC specific survival was assessed. Comparisons of renal function and overall survival between groups containing both renal units and solitary kidneys were performed using the student T-test and Kaplan-Meier analysis.
Results and Limitations
128 patients met our inclusion criteria. The median follow-up of our cohort was 16 years (10-49), mean 17 years. The median number of surgical interventions was 3 (2-10). Eighty-seven patients (68%) required repeat interventions on their ipsilateral renal unit at last follow-up, with a median time between interventions of 6.2 years (0.7-21). Overall and RCC-specific survival of the cohort was 88% and 97%, respectively. Six patients (4.7%) ultimately underwent bilateral nephrectomies.
Although renal function was better preserved in patients with both kidneys (70 vs. 53 mL/min/1.73m2, P=0.0002) there was no difference in overall survival between those with bilateral or solitary kidneys (mean 21.5 vs. 20.8 years, respectively). Limitations of the study are in its retrospective design and inclusion of closely surveilled patients.
At a minimum of 10 years follow-up after initial surgery, nephron-sparing surgery allows for excellent oncologic and functional outcomes. Despite the need for repeat surgical interventions, employing NSS allows for avoidance of dialysis in over 95% of patients.
PMCID: PMC3810017  PMID: 23083858
Familial renal cancer (FRC); bilateral renal masses (BRM); nephron-sparing surgery (NSS); partial nephrectomy; outcomes

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