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Featured researches published by Stephen D.W. Beck.


Annals of Surgical Oncology | 2003

Effect of papillary and chromophobe cell type on disease-free survival after nephrectomy for renal cell carcinoma.

Stephen D.W. Beck; Manish I. Patel; Mark E. Snyder; Michael W. Kattan; Robert J. Motzer; Victor E. Reuter; Paul Russo

BackgroundThe clinical staging of renal cortical tumors traditionally has not evaluated the potential effect of histological subtypes on survival. Evidence suggests that conventional clear cell renal cell carcinoma (RCC) and nonconventional clear cell RCC (chromophobe and papillary) have different metastatic potential. Using a large renal tumor database, we examined the effect of tumor histology on the pattern of metastasis and patient survival.MethodsAll patients with nonmetastatic renal cortical tumors undergoing partial or radical nephrectomy were identified from a renal tumor database between July 1989 and July 2002. Kaplan-Meier and Cox regression tests were used for statistical analysis.ResultsAnalysis revealed 1057 patients: 794 with conventional clear cell RCC, 157 with papillary RCC, and 106 with chromophobe RCC. Metastasis occurred in 95 conventional clear cell RCC, 9 papillary RCC, and 6 chromophobe RCC. Metastasis occurred in 95 conventional clear cell RCC, 9 papillary RCC, and 6 chromophobe RCC with a median follow-up of 34.6, 43.0, and 33.2 months, respectively. Using log-rank analysis, chromophobe and papillary RCC were associated with an improved disease-free survival at 5 years (P=.009 and .015, respectively). Multivariate analysis revealed tumor size, stage, and chromophobe histology as significant variables for disease progression.ConclusionsRenal cortical tumors have distinct histological subtypes with varying degrees of metastatic potential. Conventional clear cell RCC, which comprises two thirds of renal cortical tumors presenting with localized disease, has a less favorable outcome when compared with papillary and chromophobe RCC. Controlling for size and stage, chromophobe, and not papillary, RCC was a significant variable for disease progression compared with conventional clear cell RCC. Knowledge of renal cortical tumor histological subtype is critical for projecting prognosis, tailoring follow-up strategies, and designing clinical trials.


The Journal of Urology | 2009

Use of Ileum as Ureteral Replacement in Urological Reconstruction

Sandra A. Armatys; Matthew J. Mellon; Stephen D.W. Beck; Michael O. Koch; Richard S. Foster; Richard Bihrle

PURPOSE We reviewed indications and outcomes in patients undergoing ileal ureter replacement for ureteral reconstruction. MATERIALS AND METHODS Between December 1989 and September 2007, 105 patients underwent ileal ureter replacement, of whom 14 were excluded from study due to incomplete data. The remaining 91 patients (99 renal units) comprised the study cohort. RESULTS Mean patient age was 46.8 years and mean followup was 36.0 months. Indications for an ileal ureter were stricture following genitourinary surgery in 29 cases (31.9%), radiation induced stricture in 17 (18.7%), nonurological surgery iatrogenic injury in 16 (17.6%) and retroperitoneal fibrosis in 11 (12.1%). Only 4 patients (4.4%) had primary ureteral cancer. Long-term complications included anastomotic stricture in 3 patients (3.3%) and fistula in 6 (6.6%). Serum creatinine decreased or remained stable in 68 patients (74.7%) and hyperchloremic metabolic acidosis developed in 3. No patient complained of excessive urinary mucous production. CONCLUSIONS In 68.1% of patients indications for an ileal ureter included radiation induced stricture or iatrogenic injury. The ileal ureter is a reasonable option for long-term ureteral reconstruction with preserved renal function in carefully selected patients.


Journal of Clinical Oncology | 2005

Outcome Analysis for Patients With Elevated Serum Tumor Markers at Postchemotherapy Retroperitoneal Lymph Node Dissection

Stephen D.W. Beck; Richard S. Foster; Richard Bihrle; Lawrence H. Einhorn; John P. Donohue

PURPOSE To evaluate the therapeutic benefit of postchemotherapy retroperitoneal lymph node dissection (PCRPLND) in patients with persistently elevated serum tumor markers. PATIENTS AND METHODS One hundred fourteen patients with metastatic germ cell cancer with elevated serum tumor markers after first-line (50 patients) or second-line chemotherapy (64 patients) who underwent PCRPLND between 1977 and 2000 with a minimum follow-up of 2-years were included in this retrospective study. RESULTS The 5-year overall survival was 53.9%. Sixty-one patients (53.5%) are alive with a medium follow-up of 72 months. Fifty-three patients died of disease, with a medium time to death of 8.0 months. Mean preoperative serum alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin (betaHCG) levels were 483 ng/mL and 555 mU/mL, respectively, with no difference in 5-year survival (P = .2). Retroperitoneal pathology revealed germ cell cancer in 53.5% of patients, teratoma in 34.2% of patients, and fibrosis in 12.2% of patients, with 5-year survival rates of 31.4%, 77.5%, and 85.7%, respectively (P < .0001). Predictors of retroperitoneal pathology included an increasing serum AFP or betaHCG, betaHCG more than 100 ng/mL, redo retroperitoneal lymph node dissection (RPLND), and second-line chemotherapy. Poor prognostic variables by multivariable analysis included betaHCG status, serum AFP level, redo RPLND, and germ cell cancer in the resected specimen. CONCLUSION A subset of patients with elevated serum tumor markers after chemotherapy is curable with surgery. The prognostic factors predictive of outcome in this analysis include an increasing betaHCG, serum AFP level, redo RPLND, and germ cell cancer in the resected specimen. These factors, along with clinical and surgical experience, should aid in determining the appropriate integration of surgery and chemotherapy in this population.


Journal of Vascular Surgery | 1998

Long-term results after inferior vena caval resection during retroperitoneal lymphadenectomy for metastatic germ cell cancer

Stephen D.W. Beck; Stephen G. Lalka; John P. Donohue

PURPOSE The long-term sequelae of inferior vena caval (IVC) resection during retroperitoneal lymph node dissection for metastatic nonseminomatous germ cell testis tumor (NSGCT) were assessed. METHODS Between December 1973 and September 1996, 2126 of our patients underwent RPLND for retroperitoneal nodal metastases from NSGCT; 955 had bulky disease (stages B2, B3, or C) after cytoreduction chemotherapy. Of this latter group, 65 patients (6.8%) required infrarenal IVC resection during tumor excision for cure. Our protocol does not include IVC reconstruction in such cases. Indications for IVC resection included tumor encasement or encroachment, postchemotherapy desmoplastic compression, or thrombus with tumor or clot in which cavotomy and thrombectomy cannot be performed. RESULTS Twenty-four of the 65 patients (postoperative follow-up period range, 11 months to 16 years; median, 89 months) were alive and able to be examined or interviewed by written and/or phone survey to assess the long-term morbidity of their IVC resection. Based on the 1994 American Venous Forum International Consensus Committee reporting standards, the clinical classifications of these 24 patients were C0A (4), C3S (4), C4A (2), C4S (13), and C6A (1). Long-term disability was mild or absent in 75% of these patients. CONCLUSION Only 1 (4.2%) of the patients surveyed had chronic venous sequelae that would fulfill the accepted criteria for subsequent elective IVC reconstruction. Despite recent reports of IVC reconstruction demonstrating relatively good patency rates and low morbidity, the addition of such a complex, time-consuming procedure to extensive retroperitoneal lymph node dissection for metastatic NSGCT involving IVC resection is generally not necessary.


Cancer | 2007

Is full bilateral retroperitoneal lymph node dissection always necessary for postchemotherapy residual tumor

Stephen D.W. Beck; Richard S. Foster; Richard Bihrle; John P. Donohue; Lawrence H. Einhorn

Traditionally, postchemotherapy (PC) surgery for metastatic nonseminomatous germ cell tumor (NSGCT) has used a full bilateral retroperitoneal lymph node dissection (RPLND) from the crus of the diaphragm to the bifurcation of the common iliac arteries, from ureter to ureter. With the primary landing zone well defined in low‐volume retroperitoneal disease, the authors performed modified dissections in the PC setting in a select population; and, herein, they report disease outcome.


The Journal of Urology | 1999

CONCEALED PENIS IN CHILDHOOD: A SPECTRUM OF ETIOLOGY AND TREATMENT

Anthony J. Casale; Stephen D.W. Beck; Mark P. Cain; Mark C. Adams; Richard C. Rink

PURPOSE Concealed penis is an uncommon condition due to poor skin fixation at the base of the penis, cicatricial scarring after penile surgery and excessive obesity. The condition varies in severity and several surgical options are available, such as excision of previous scarring, degloving the penile shaft, reconstructing the penile shaft skin with flaps, fixing the penile skin at the penopubic and penoscrotal angles, and removing excess suprapubic fat. MATERIALS AND METHODS We reviewed the records of 43 patients treated for concealed penis from 1993 to 1998. We categorized the cases as type 1-congenital concealed penis, type 2-concealed penis due to scarring from previous surgery and type 3-complex cases involving excessive obesity. Cases were reviewed in regard to surgical techniques and outcomes. We identified 18 type 1, 18 type 2 and 7 type 3 cases. Mean age of type 1 patients at surgery was 12.4 months with 1 patient presented at age 7 years. None had previously undergone penile surgery. All patients underwent complete penile degloving. To reconstruct the penile shaft flaps or Z-plasties with penile skin were used in 12 patients and scrotal skin flaps were used in 2. In 12 patients the penile skin was fixed at the penoscrotal and penopubic angles to maintain penile length and in 2 excess fat was excised. Mean age of type 2 patients at surgery was 19.8 months. All had previously undergone surgery, including hypospadias in 1 and circumcision in 17. All patients underwent complete penile degloving and the cicatricial scar that trapped the penis was excised. Penile skin flaps and Z-plasties were used in 12 cases, scrotal skin flaps were used for reconstruction in 2 and skin grafting was done in 1. In 10 patients the penile skin was fixed with sutures to maintain penile length. Mean age of type 3 patients at surgery was 15.8 years. Of the 7 boys 6 had previously undergone penile surgery. All required extensive scar excision and complex reconstruction involving penile skin flaps in 3, scrotal flaps in 5 and penile skin fixation in 6. Excessive suprapubic fat was removed in 5 patients, of whom 3 underwent liposuction. RESULTS Surgical results were uniformly good in type 1 patients except in 1 who was believed to have excessive suprapubic fat. Results were good in 14 of the 18 type 2 patients, although 2 retained excessive suprapubic fat and 2 had some unsightly scarring. No type 1 or 2 patient required additional surgery. Of the 7 type 3 patients 6 had a good result and required no additional surgery. One patient has recurrent concealed penis after 2 procedures and awaits additional surgery. CONCLUSIONS Concealed penis has a varied etiology and requires a flexible surgical approach. The common surgical options in all cases include complete penile degloving, excising the scarring due to previous surgery, removing excess suprapubic fat, reconstructing the penile skin with local flaps, and fixing the penile skin at the penopubic and penoscrotal angles.


Clinical Cancer Research | 2006

Interphase Fluorescence In situ Hybridization Analysis of Chromosome 12p Abnormalities Is Useful for Distinguishing Epidermoid Cysts of the Testis from Pure Mature Teratoma

Liang Cheng; Shaobo Zhang; Gregory T. MacLennan; Christopher Poulos; Ming Tse Sung; Stephen D.W. Beck; Richard S. Foster

Purpose: The distinction of epidermoid cyst of the testis from teratoma is of critical importance because the former is benign and the latter is a malignant tumor that may have associated metastasis of either teratomatous or non–teratomatous germ cell tumor types. Chromosome 12p abnormalities are seen in the vast majority of testicular germ cell tumors of adults and are present in all histologic subtypes. In this study, we investigated the clinical utility of interphase fluorescence in situ hybridization (FISH) analysis of chromosome 12p abnormalities for distinguishing epidermoid cysts of the testis from pure mature teratoma. Experimental Design: Sixteen testicular epidermoid cysts and 17 testicular teratomas were investigated for isochromosome 12p [i(12p)] and 12p overrepresentation using interphase FISH analysis. Results: Neither i(12p) nor 12p overrepresentation were observed in 16 epidermoid cyst cases, whereas i(12p) was detected in 76% of teratomas and 12p overrepresentation was identified in 29% of teratomas. Overall, 88% of testicular teratomas had chromosome 12p abnormalities. Conclusions: FISH identification of i(12p) and/or 12p overrepresentation in routinely processed surgical specimens is a useful ancillary diagnostic tool in distinguishing testicular epidermoid cysts from teratoma.


The Journal of Urology | 2002

MULTILAYERED SMALL INTESTINAL SUBMUCOSA IS INFERIOR TO AUTOLOGOUS BOWEL FOR LAPAROSCOPIC BLADDER AUGMENTATION

Ryan F. Paterson; David A. Lifshitz; Stephen D.W. Beck; Tibério M. Siqueira; Liang Cheng; James E. Lingeman; Arieh L. Shalhav

PURPOSE Bladder augmentation is most commonly performed with ileum. However, porcine small intestinal submucosa has been reported as a substitute for bowel for incorporation into the urinary tract. We assessed the feasibility and long-term 12-month results of laparoscopic bladder augmentation with ileum or multilayered small intestinal submucosa (Cook Biotech, Spencer, Indiana) in a porcine model. MATERIALS AND METHODS We performed laparoscopically assisted hemicystectomy and bladder augmentation in 24 female Yucatan mini-pigs using an ileal segment (12) or multilayered small intestinal submucosa (12). The followup protocol included anesthetic bladder capacity, renal ultrasonography and serum chemistry. At 3, 6 and 12 months, respectively, 4 animals per group were scheduled for sacrifice and pathological analysis. RESULTS Despite longer anastomotic time in the multilayered small intestinal submucosa group (120 versus 91 minutes, p = 0.026) total operative time was similar in the 2 groups. In each group bladder capacity increased with time but by 12 months bladder capacity was significantly better in the bowel than in the small intestinal submucosa group (825 versus 431 cc, p = 0.016). At 3 months pathological evaluation revealed that the multilayered regenerated bladder patch had shrunken and by 6 months it was replaced by dense calcified scar tissue. Long-term 6 and 12-month bladder capacity in the small intestinal submucosa group was the result of the regeneration of native bladder with exclusion of the whole multilayered patch in the majority of cases. CONCLUSIONS Laparoscopic bladder augmentation using multilayered small intestinal submucosa produced functional and pathological results inferior to those of bowel at 12-month followup in a porcine model.


The Journal of Pathology | 2007

Molecular genetic evidence supporting the neoplastic nature of stromal cells in 'fibrosis' after chemotherapy for testicular germ cell tumours

Liang Cheng; Shaobo Zhang; Mingsheng Wang; Darrell D. Davidson; Mj Morton; J Huang; S Zheng; Timothy D. Jones; Stephen D.W. Beck; Richard S. Foster

A residual retroperitoneal mass containing only fibrosis and necrosis is present in 40–52% of patients with advanced testicular germ cell tumours after chemotherapy. The biological nature and genetic characteristics of the stromal cells in these residual masses have not been adequately investigated. Laser‐microdissected stromal cells from 27 patients who underwent retroperitoneal lymph node dissection after chemotherapy for metastatic testicular germ cell tumour were analysed. Allelic loss in the stromal cells of fibrosis was present at one or more of the ten microsatellite DNA loci examined in 23 (85%) of the cases. Chromosome arm 12p anomalies, the hallmark of germ cell neoplasia, were present in nine (33%) cases. The high frequency of allelic losses and chromosome arm 12p anomalies in the stromal cells from residual retroperitoneal fibrous masses after chemotherapy for testicular germ cell tumours suggests that the stromal cells are derived from the same tumour progenitor cells as the pre‐existing metastatic germ cell tumour. Copyright


The Journal of Urology | 2001

Aortic replacement during post-chemotherapy retroperitoneal lymph node dissection

Stephen D.W. Beck; Richard S. Foster; Richard Bihrle; Michael O. Koch; Gregory R. Wahle; John P. Donohue

PURPOSE We reviewed the records of 15 patients with metastatic germ cell cancer who underwent aortic resection and replacement during post-chemotherapy retroperitoneal lymph node dissection to determine the morbidity and the therapeutic benefit. MATERIALS AND METHODS Between 1970 and 1998, 1,250 patients underwent post-chemotherapy retroperitoneal lymph node dissection. Our retrospective review revealed that 15 patients underwent aortic replacement at that operation. RESULTS In addition to aortic replacement 11 patients underwent 15 additional procedures, including nephrectomy in 7, vena caval resection in 3, pulmonary resection in 1, small bowel resection in 2, 1 hepatic resection in 1 and L4 vertebrectomy in 1. No patient had necrosis as the only pathological condition. Three patients (20%) had teratoma and 12 (80%) had viable tumor in the retroperitoneal specimen. All 4 patients who underwent post-chemotherapy retroperitoneal lymph node dissection and aortic replacement after induction chemotherapy alone have no evidence of disease. Only 1 of the 11 patients who received salvage chemotherapy with or without previous post-chemotherapy retroperitoneal lymph node dissection have no evidence of disease. Overall 33% of the patients have no evidence of disease. There were no graft related complications. CONCLUSIONS Aortic resection at post-chemotherapy retroperitoneal lymph node dissection is justified based on therapeutic benefit and morbidity.

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