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Dive into the research topics where Donald E. Engen is active.

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Featured researches published by Donald E. Engen.


The Journal of Urology | 1999

Prospective analysis of intraoperative frozen needle biopsy of solid renal masses in adults.

Christopher Dechet; Thomas J. Sebo; George M. Farrow; Michael L. Blute; Donald E. Engen; Horst Zincke

PURPOSE We prospectively determined the accuracy of intraoperative needle biopsy of solid renal masses. MATERIALS AND METHODS A total of 103 patients diagnosed with a solid renal mass and scheduled for surgery were prospectively evaluated. Radical or partial nephrectomy was performed, and biopsy of the surgical specimen was done twice through the tumor using an 18 gauge biopsy gun. Biopsy specimens of 106 tumors were sent for frozen sectioning, stained with hematoxylin and eosin, and reviewed by 2 independent pathologists blinded to each other and whole tissue specimens. Biopsy results were compared to whole tissue specimens. RESULTS Specimens were obtained from 60 radical and 46 partial nephrectomy cases. Malignant neoplasms were present in 91 cases (86%). Overall, 15 cases (14%) were benign, of which 11 were oncocytomas. If lesions 4 cm. or less only were included in analysis, the incidence of benign lesions increased to 22%. Overall accuracy of the 2 pathologists was 76 and 80%. Nondiagnostic rates were 11 and 17%. Both observers incorrectly diagnosed 4 malignant lesions (5%) as benign, and incorrectly diagnosed 3 and 5 benign lesions (21 and 36%), respectively, as malignant. Analysis of values for both observers yielded a sensitivity of 77 and 84%, specificity 60 and 73%, positive predictive value 94 and 96%, and negative predictive value 69 and 73%. CONCLUSIONS Overall frozen needle biopsy was accurate in more than 75% of cases and showed an excellent positive predictive value for carcinoma of more than 94%. Unfortunately, there was a large degree of inaccuracy for benign lesions and we do not recommend the routine use of intraoperative frozen needle biopsy to guide surgical decision making.


The Journal of Urology | 2000

Benefit of adjuvant radiation therapy for localized prostate cancer with a positive surgical margin

Bradley C. Leibovich; Donald E. Engen; David E. Patterson; Thomas M. Pisansky; Erik E. Alexander; Michael L. Blute; Erik J. Bergstralh; Horst Zincke

PURPOSE Positive surgical margins are common after radical prostatectomy, and the role of adjuvant therapy in such cases is controversial. We determined the benefit of postoperative external beam radiation therapy in patients with margin positive prostate cancer with respect to biochemical progression or cancer recurrence. To decrease confounding factors that may affect the likelihood of biochemical progression our study was limited to men with organ confined cancer and a single positive margin. MATERIALS AND METHODS We retrospectively evaluated the records of a nested matched cohort of 76 patients with pathological stage T2N0 prostate cancer and a single positive margin who underwent adjuvant radiation therapy within 3 months of radical prostatectomy. There was a positive margin at the prostatic apex in 35 cases, prostatic base in 18, posterior prostate in 11, urethra in 7, and prostatic apex and urethra in 5. These patients were matched 1:1 with 76 controls who did not receive adjuvant radiation therapy. Neither group received androgen deprivation therapy. Patients and controls were matched exactly for the margin positive site, age at surgery, preoperative serum prostate specific antigen, Gleason score and DNA ploidy. Biochemical relapse was defined as posttreatment PSA greater than 0.2 ng./ml. RESULTS Overall there was significant estimated improvement plus or minus standard error in 5-year clinical and biochemical progression-free survival in 88%+/-5% versus 59%+/-11% of patients treated with adjuvant radiation therapy versus no radiation therapy (p = 0.005). No patient who received radiation therapy had local or distant recurrence, while 16% of controls had recurrence (p = 0.015). When stratified by site of margin positivity, the 5-year estimated clinical and biochemical progression-free rate in 18 cases and controls with a positive base margin was 95%+/-15% and 65%+/-13%, respectively (p = 0.02). The rate in 35 cases and cases with a positive apex margin was 95%+/-5% and 64%+/-15%, respectively (p = 0.07). Limited sample size precluded analysis of the other sites. CONCLUSIONS Patients with localized prostate cancer and a singe positive surgical margin appear to have a lower rate of biochemical relapse at 5 years when adjuvant radiation therapy is administered. Definitive evidence of the beneficial effect of adjuvant radiation therapy for patients with involved surgical margins awaits conclusion of randomized clinical trials.


The Journal of Urology | 1987

The Clinical Spectrum of Granulomatous Prostatitis: A Report of 200 Cases

Thomas J. Stillwell; Donald E. Engen; George M. Farrow

Granulomatous prostatitis, reviewed in 200 tissue-diagnosed cases, occurred in 0.8 per cent of the benign inflammatory prostatic specimens. Often the disease followed a recent urinary tract infection (71 per cent) and was suspicious clinically for prostatic cancer (59 per cent). The diagnosis usually was made by needle biopsy or at transurethral prostatectomy (94 per cent). Most cases of granulomatous prostatitis were classified as nonspecific. The recently identified entity of post-transurethral resection granulomatous prostatitis was found in 49 patients. A proposed new category of granulomatous prostatitis that is secondary to systemic granulomatous diseases was documented in 6 patients. Most cases of granulomatous prostatitis resolved spontaneously and required no specific therapy.


Mayo Clinic Proceedings | 1985

Treatment of Renal Cell Carcinoma by In Situ Partial Nephrectomy and Extracorporeal Operation With Autotransplantation

Horst Zincke; Donald E. Engen; Karen M. Henning; Michael W. McDonald

During a 10-year period, 33 patients underwent in situ enucleation, in situ partial nephrectomy, or an extracorporeal operation for low-grade (1 or 2), low-stage (I or II), bilateral or solitary renal cell carcinoma. Only one patient (3%) (who had undergone in situ partial nephrectomy) had local recurrence; the projected 5-year rates of nonprogression of disease and survival from death due to cancer only were 76% and 87%, respectively. A group of patients who were closely matched for grade and stage of renal cell cancer underwent traditional transabdominal radical nephrectomy during the same time interval and had rates of nonprogression and survival similar to those of the conservative surgical group. Thus, in selected patients with low-grade, low-stage renal cell cancer, conservative surgical treatment (that is, renal parenchyma-saving procedures) can produce favorable results without the side effects (such as renal failure) associated with ablative renal operations.


Diseases of The Colon & Rectum | 1998

Management of Acquired rectourinary fistulas: Outcome according to cause

M. Muñoz; Heidi Nelson; Jeffrey R. Harrington; Gregory G. Tsiotos; Richard M. Devine; Donald E. Engen

PURPOSE: Acquired rectourinary fistulas, an infrequent complication of pelvic conditions, remain a therapeutic problem for which neither a widely accepted classification nor long-term outcome data are available. This study was designed to provide a new etiologic classification system and examine the success of various surgical therapies. It also looked at the need for permanent fecal or urinary diversion or radical excision depending on the cause of the fistula,i.e., benignvs. malignancy-related. METHODS: A retrospective analysis was made of 41 patients treated for acquired rectourinary fistulas between 1980 and 1995. Acquired rectourinary fistulas were classified as 1) benign but caused by Crohns disease, trauma, perirectal sepsis, or iatrogenic injury; and 2) malignancy-related fistulas secondary to neoplasm, radiation, surgery, or combined tumor and treatment effects. Surgical interventions were classified as repair, excision, fecal diversion, and urinary diversion. RESULTS: Thirty-seven males and 4 females with acquired rectourinary fistula were identified with a mean age of 62 (range, 28–90) years. Nineteen patients had fistulas involving their urethras, and 22 patients had fistulas involving the bladder. Eight patients were not treated surgically; one was not treated because of an advanced malignancy, three because of patient preference, three because of sepsis, and one because of a poor general condition. Of the remaining 33 patients, nine had benign fistulas of which two were the result of Crohns disease, two were the result of trauma, two were from an iatrogenic response, and three were from perirectal sepsis. Twenty-four patients had malignancy-re-lated fistulas, and five patients had neoplasm at their fistula sites. The remaining 19 patients had malignancy-related fistulas that were the result of cancer treatments. Of the 19 malignancy-related fistulas, 5 were from radiation, 9 were from surgical trauma, and 5 were from radiation and surgical trauma. Forty-nine percent of the patients had undergone attempts at fistula treatment before referral. A resolution of symptoms after initial and reoperative surgery occurred more often in patients with benign fistulas (44 and 100 percent; mean, 1.8 surgeries per patient) compared with malignancy-related fistulas (21 and 88 percent; mean, 2.1 surgeries per patient). The rates of permanent fecal, urinary, and fecal plus urinary diversion were also lower for benign fistulas (11, 0, and 33 percent) compared with malignancy-related fistulas (13, 8, and 54 percent). Permanent diversion was avoided in 56 percent of the benign fistulas but in only 25 percent of the malignancy-related fistulas. The rates of excisional and radical (ileal conduit) surgery were lower for benign fistulas than for malignancy-related fistulas (44 and 11 percentvs. 50 and 54 percent). CONCLUSION: Successful management of rectourinary fistulas typically requires aggressive reoperative therapy with permanent diversion more often required for malignancy-related fistulas. Better outcomes can be anticipated for benign fistulas.


The Journal of Urology | 2000

PUBOPERINEALES: MUSCULAR BOUNDARIES OF THE MALE UROGENITAL HIATUS IN 3D FROM MAGNETIC RESONANCE IMAGING

Robert P. Myers; Donald R. Cahill; Paul A. Kay; Jon J. Camp; Richard M. Devine; Bernard F. King; Donald E. Engen

PURPOSE The aims of this report are 1) to extend our previous two-dimensional magnetic resonance imaging study to create a three-dimensional image of the pelvic floor, including the puboperinealis, the most anteromedial component of the levator ani; 2) to clarify the historical controversy about this particular component of the levator ani; and 3) to present clinical implications of this muscle with respect to urinary continence and radical prostatectomy. MATERIALS AND METHODS We reused the axial magnetic resonance imaging series from 1 of 15 men in a previous series. Analyze AVWTM allowed creation of three-dimensional images. Further, a movie clip of all three-dimensional images was developed and placed at the manuscript-dedicated Web site: http://www.mayo. edu/ppmovie/pp.html. RESULTS Our three-dimensional images show how the puboperinealis portion of the levator ani flanks the urethra as it courses from the pubis to its insertion in the perineal body. CONCLUSIONS The puboperinealis corresponds to muscles previously designated as the levator prostatae, Wilsons muscle, pubourethralis, and levator urethrae, among others. The images suggest that the puboperinealis is the muscle most responsible for the quick stop phenomenon of urination in the male. Our study supports the suggestion that weakening of the puboperinealis by transection, traction injury, or denervation may affect urinary continence after radical prostatectomy.


The Journal of Urology | 1989

Primary Signet Ring Cell Adenocarcinoma of the Bladder

Michael L. Blute; Donald E. Engen; William D. Travis; Larry K. Kvols

Primary signet ring cell adenocarcinoma of the bladder accounts for less than 1 per cent of all primary bladder neoplasms. This tumor is insidious because of its subepithelial infiltrative nature, which makes diagnosis possible only late in the course of the disease. Survival is poor; greater than 50 per cent of the patients are dead within a year after diagnosis. Exenterative procedures offer the only hope of palliation; irradiation and chemotherapy have not been effective. We add 5 cases of primary signet ring cell adenocarcinoma of the bladder and 1 case of high grade transitional cell carcinoma of the bladder with signet ring cell foci to the 14 cases reported in the literature. Pathological correlation supports the origin of this neoplasm from totipotential transitional epithelium.


Transplantation | 1991

MORBIDITY OF PANCREAS TRANSPLANTATION DURING CADAVERIC RENAL TRANSPLANTATION

Charles B. Rosen; Peter P. Frohnert; Jorge A. Velosa; Donald E. Engen

Simultaneous transplantation of the pancreas is an option for diabetic patients undergoing kidney transplantation to attempt to halt progression of diabetic complications, but the additional risk imposed by the procedure is unclear. Our aim was to determine the morbidity attributable to pancreas transplantation during simultaneous pancreas and kidney transplantation. We compared the first posttransplant year of 18 consecutive recipients of combined pancreas and kidney transplantation to 18 consecutive recipients of kidney transplantation alone. All patients received cadaver donor allografts between 1986 and 1989, and had type I diabetes mellitus with chronic renal failure. There were no differences in patient survival (94% both groups) or satisfactory renal allograft function (89% pancreas/kidney group, 83% kidney group) up to 18 months after transplantation. Eighty-eight percent of pancreas allografts were functioning satisfactorily at 18 months. There was a mean (+/- SD) of 1.5 +/- 1.0 acute rejection episodes per patient for the pancreas/kidney group compared to 0.8 +/- 6 for the kidney-only group (P less than 0.02). Cytomegalovirus infection and wound complications were each encountered more often after pancreas/kidney transplantation than kidney transplantation alone, and together with rejection accounted for a difference in days of hospitalization during the first year (71 +/- 34 vs. 27 +/- 13, P less than 0.001). We conclude that simultaneous pancreas transplantation during cadaver donor kidney transplantation accounted for more frequent rejection episodes, CMV infections, and wound complications. These complications resulted in more hospitalization for patients undergoing simultaneous pancreas/kidney transplantation than kidney transplantation alone.


Transplantation | 1990

Differential diagnosis of hypoamylasuria in pancreas allograft recipients with urinary exocrine drainage.

Stephen R. Munn; Donald E. Engen; Darlene Barr; Herschel A. Carpenter; James D. Perkins

We have studied the histopathologic correlates of a significantly decreased urinary amylase excretion rate (UAER) to determine its reliability in predicting the presence of cellular rejection within pancreas allografts drained via a duodenocystostomy. Significant hypoamylasuria in pancreas allograft recipients was defined as a diminution of greater than 50% in UAER sustained for greater than 36 hr and not associated with a decrease in serum amylase activity. We observed 18 such episodes of hypoamylasuria in 13 of 18 patients receiving pancreas allografts. Pancreaticoduodenal material was obtained during 11 of these episodes, one attempt failed, and for the remaining 6 episodes we obtained 3 renal allograft biopsy specimens. Histopathologic examination of the 14 specimens revealed cellular rejection in 9 (64%), fibrosis in 2 (14%), enzymatic necrosis in 1 (7%), cytomegaloviral pancreatitis in 1 (7%), and no abnormal features in 1 (7%). During these 14 episodes, a genetically identical renal allograft was present for 11 and showed signs of dysfunction in 9; however, the pancreatic histologic features suggested rejection in only 7 of the 9. Thus even the combination of hypoamylasuria and renal dysfunction in recipients of genetically identical organs was not fully reliable in predicting pancreas allograft rejection. In addition, the interval between organ implantation and onset of hypoamylasuria did not predict the histologic diagnosis. As with other solid-organ allografts, biopsy is a useful adjuvant for determining patient management in the presence of organ dysfunction.


Journal of Ultrasound in Medicine | 2002

Sonographically guided percutaneous radio frequency ablation of a renal cell carcinoma in a transplanted kidney.

J. William Charboneau; Michael T. O'Loughlin; Dawn S. Milliner; Donald E. Engen

Radio frequency ablation is an effective treatment for focal renal cell carcinoma (RCC). We report a patient with RCC in a transplanted kidney that was successfully treated with percutaneous sonographically guided radio frequency ablation.

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Michael L. Blute

University of Wisconsin-Madison

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