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Biomedical subjects

R C Benson

Publications and source records attributed to R C Benson.

At least 55 records · Page 3Linked to original sources
PubMed1987

Preoperative magnetic resonance imaging of vena caval tumor thrombi: experience with 5 cases.

Magnetic resonance scans were performed preoperatively in 5 patients who underwent surgical removal of renal or adrenal tumors with direct extension of the tumor into the vena cava. Of the patients 4 had renal cell carcinoma and 1 had adrenocortical carcinoma. Magnetic resonance imaging staged correctly the level of vena caval tumor thrombus involvement in 4 patients and missed the presence of right atrial tumor extension in 1. This noninvasive imaging modality can be used instead of contrast venography in most patients to assess the presence and extent of vena caval tumor involvement by renal cell carcinoma. Contrast venography should be used for those patients with suspected cardiac involvement and for those whose tumor thrombus extent remains unclear after magnetic resonance imaging.

Adrenal Cortex Neoplasms↗
PubMed1987

Perioperative and postoperative complications from bilateral pelvic lymphadenectomy and radical retropubic prostatectomy.

The complications experienced by 692 consecutive patients who underwent bilateral pelvic lymphadenectomy and radical retropubic prostatectomy from 1978 through 1984 were analyzed. Four patients (0.6 per cent) died in the perioperative or early postoperative period. Pulmonary embolus developed in 19 patients (2.7 per cent) and severe to total urinary incontinence occurred in 34 (5 per cent). Our large series suggests that radical retropubic prostatectomy with staging bilateral pelvic lymphadenectomy can be performed in a safe manner with minimal postoperative morbidity.

Adenocarcinoma↗
PubMed1986

Congenital renal arteriovenous malformations.

Congenital arteriovenous malformations are rare lesions of the kidney. We evaluated the clinical course of 15 patients with this lesion who were seen between 1950 and 1984. There were 9 women and 6 men, and the median age at diagnosis was 48 years. Patients presented most commonly with hematuria (93 per cent) or hypertension (53 per cent). Of the 15 patients 10 underwent nephrectomy because of gross hematuria or the perceived risk of significant bleeding, or in an effort to control hypertension. None of the 10 patients has required a further operation and those who were hypertensive preoperatively remained hypertensive postoperatively. The remaining 5 patients were treated conservatively, either with observation or antihypertensive medications. All 5 patients had microscopic hematuria and none has required further therapy. It would seem that neither microscopic hematuria nor controlled hypertension is an indication alone for nephrectomy.

Adolescent↗
PubMed1986

Bladder replacement with use of a detubularized right colonic segment: preliminary report of a new technique.

Dissatisfaction with the long-term results of cutaneous urinary diversion and a demand for a more socially acceptable solution have prompted the development of procedures that allow continent urinary diversion. Creation of an internal reservoir from reconstructed bowel segments, which is anastomosed to the patient's urethra and allows continence and urination through the urethra, is a particularly attractive option. We describe a technique that is relatively easy to perform and that incorporates a detubularized right colonic segment. The advantages of this procedure are discussed.

Aged↗
PubMed1986

Laser photodynamic therapy for bladder cancer.

The lack of a tumor-localization aid for transitional cell carcinoma of the bladder and the known cytotoxic effect of light-activated intracellular hematoporphyrin derivative (HpD) prompted the initiation of a trial of HpD photodynamic therapy in patients with focal and diffuse bladder cancer. An argon-ion, pumped-dye laser was used as a source of red light. In 15 patients with focal disease and circumscribed treatment, 3-month follow-up cystoscopic examination showed disappearance of the lesions, but the subsequent recurrence rate seemed high. Therefore, whole-bladder HpD photodynamic therapy was administered to 14 patients with diffuse resistant carcinoma in situ. Three of these patients had focal recurrent disease. The only adverse effects of therapy were cutaneous photosensitivity and bladder irritability. HpD seems to be a good tumor-localizing aid for transitional cell carcinoma of the bladder, and HpD photodynamic therapy effectively destroys this type of carcinoma.

Antineoplastic Agents↗
PubMed1986

Estramustine phosphate compared with diethylstilbestrol. A randomized, double-blind, crossover trial for stage D prostate cancer.

In a double-blind, crossover comparison, 236 patients with metastatic prostate cancer were randomized to receive estramustine phosphate (EMP) or diethylstilbestrol (DES). Previously castrated patients (66) were separately randomized. Patients kept taking their first drug until progression was proved by objective studies, at which time alternative treatment was begun. The primary determinant of efficacy was the duration between start of therapy and date of objective progression. Uncastrated patients treated with EMP had a significantly longer duration without progression than those treated with DES (p less than 0.01). The following subcategories of entry were further evaluated: little or no pain, moderate to severe pain, little reduction in activity, significant reduction in activity, presence or absence of cardiovascular disease, age above or below 70 years, and "good" or "bad" histology. For all but the last category, EMP was statistically superior to DES. Patients who underwent orchiectomy less than 3 months before randomization had nonprogression rates similar to those for noncastrated men in both groups. Secondary (crossover) therapy was less effective than first therapy in both groups: 46% of patients receiving EMP and 40% receiving DES had no progression at 6 months. Clinical and laboratory adverse experiences were similar for both drugs, except that gastrointestinal disturbances were more common in the EMP group.

Clinical Trials as Topic↗
PubMed1986

Indwelling ureteral stents: percutaneous management of complications.

Complications of indwelling ureteral stents were managed percutaneously in 13 patients. These complications consisted of three fractured, three heavily encrusted, and seven migrated stents. While most ureteral stent malfunctions are routinely managed with retrograde techniques, the percutaneous approach allows effective clinical management in selected cases in which extensive renal stone material or brittle intrarenal stent fragments are present or when previous surgery or ureteral strictures do not permit a retrograde approach. Fluoroscopically guided removal of migrated stents and percutaneous endoscopic techniques, for complex cases such as those requiring stone removal, were successful and without complications.

Adult↗
PubMed1986

Integral photoradiation therapy of multifocal bladder tumors.

Focal and diffuse hematoporphyrin derivative (HpD) photodynamic therapy was used for the treatment of resistant transitional cell carcinoma in situ (Tis) in 30 patients. Patients were given HpD intravenously followed by either focal light irradiation (630 nm) or diffuse bladder irradiation via a light bulb fiber. The light source was an argon ion pumped dye laser circulating rhodamine B dye. All patients were followed with periodic cystoscopic examinations, bladder biopsies, and urine cytologic examinations. All of the 15 patients who underwent focal therapy had biopsy and cytologic evidence of disappearance of the lesion in the treated area at the 3-month follow-up cystoscopic examination. Eight patients have experienced one or more recurrent lesions either in the treated area or in distant areas, and in each the recurrence was successfully treated with HpD photodynamic therapy. Eight of the 11 patients with diffuse Tis have returned for their 3-month follow-up evaluation, and all demonstrated disappearance of tumor (3 of these 8 patients have subsequently developed focal recurrent Tis). Four patients had diffuse Tis plus Ta lesions (2 patients) or T2 lesions (2 patients), and all had disappearance of the Tis, but persistence of the Ta or T2 disease. We conclude that HpD photodynamic therapy appears effective in the treatment of resistant Tis.

Aged↗
PubMed1986

Laser use in open surgery and external lesions.

The Nd:YAG laser, the CO2 laser, and the argon laser have all been used as cutting or hemostatic tools in open urologic surgery and in the treatment of skin lesions of the genitalia with the choice of instrument being dictated by the characteristics of each wavelength. Results to date in open surgical applications have not been dramatic. For the treatment of benign and malignant lesions of the external genitalia, lasers may prove to have a significant advantage over existing methods of treatment.

Animals↗
PubMed1985

Androgen receptor binding activity in human prostate cancer.

Androgen binding (cytosol and nucleus) was measured in tissue obtained from 223 untreated patients with proven prostate cancer (199 primary tumor, 24 malignant lymph nodes), 19 patients with hormone refractory cancer, and 46 patients with benign prostatic hyperplasia (BPH). The mean binding in both the cytosol and nucleus was significantly higher for patients with cancer than for those with BPH. Binding appeared to correlate with tumor stage. Androgen binding in malignant nodes can differ from that in the primary tissue and can vary from node to node in the same patient. Results obtained from an assay using a single saturating concentration of R1881 correlated well with those calculated from a full six-point Scatchard analysis when an adequate amount (500 mg) of tissue was available. However, binding results obtained from a single-point analysis performed on needle biopsy specimens (about 50 mg) obtained before complete surgical removal of the prostate correlated poorly with those derived from a full six-point analysis performed on tissue (500-1000 mg) removed from the center of the malignancy. Androgen binding in nuclear extracts of histologically benign tissue adjacent to the malignancy was significantly higher than in nuclear extracts of BPH tissue. Cytosolic androgen binding in tissue removed from patients who were refractory to hormonal therapy was higher than in tissue from untreated cancer patients. The binding of estradiol by extracts of benign and malignant prostate tissue was low or absent and, thus, did not appear to be a significant phenomenon.

Androgens↗
PubMed1985

Acute toxicity and preliminary therapeutic results of pelvic lymphadenectomy combined with transperineal interstitial implantation of 192IR and external beam radiotherapy for locally advanced prostate cancer.

We have developed a combined modality approach for treatment of locally advanced prostate cancer consisting of: surgical staging with lymphadenectomy; transperineal placement of afterloading needles for a course of 192Ir brachytherapy; and a course of moderate-dose external beam irradiation to tight prostatic fields. The flexibility of the treatment permits adaptation of the dose to any tumor configuration. A total of 23 patients have been treated to date; 18 are available for treatment review and 14 for acute toxicity analysis. Significant morbidity has occurred in only 2 patients, 1 with a pelvic hematoma and 1 with hematoma in the wound. Local tumor response has been excellent in all but 1 patient. A good degree of symptomatic improvement was observed at the three-month follow-up. This approach appears to be safe and effective at this time. A brief review of the technique and the rationale for its use are also presented.

Adenocarcinoma↗
PubMed1985

Vacuum cleaner injury to penis: a common urologic problem?

Erotic stimulation by the use of vacuum cleaners or electric brooms appears to be a common form of masturbation. Unfortunately, and contrary to apparent public appreciation, injury due to this form of autostimulation may not be unusual. Five cases of significant penile trauma resulting from this form of masturbation are presented, with a spectrum of severe injuries, including loss of the glans penis.

Adolescent↗
PubMed1985

Pelvic lymphadenectomy combined with transperineal interstitial implantation of iridium-192 and external beam radiotherapy for locally advanced prostatic carcinoma: technical description.

Regardless of the treatment modality, control of locally advanced extracapsular prostatic cancer remains a therapeutic challenge. At the Mayo Clinic, we have recently developed a combined approach for surgically staged patients employing interstitial irradiation with 192 Iridium via a transperineal template. The Martinez Universal Perineal Interstitial Template (MUPIT-II) and moderate doses of external beam irradiation. The procedure consists of: 1) preoperative single dose external beam irradiation to decrease potential for tumor seeding or showering of malignant cells during MUPIT-II placement; 2) adequate surgical staging through a bilateral retroperitoneal lymphadenectomy; 3) transperineal interstitial implantation of the tumor and retropubic palpation of the needles to verify proper position; 4) intraoperative X rays are taken and used for documentation of needle position as well as for calculation and optimization of the implant dose distribution with the aid of a computerized system; 5) moderate doses of external beam irradiation postoperatively to the prostate with adequate margins. Our favorable preliminary results obtained in 18 patients treated with the above approach warrant the continuation of this trial. Details of this technique are presented.

Adenocarcinoma↗
PubMed1985

Treatment of diffuse transitional cell carcinoma in situ by whole bladder hematoporphyrin derivative photodynamic therapy.

A total of 10 patients with diffuse, resistant transitional cell carcinoma of the bladder underwent whole bladder hematoporphyrin derivative photodynamic therapy in which a new light bulb fiber was used to deliver red light (630 nm.) from an argon pumped dye laser. Six patients who had carcinoma in situ alone had a complete response, 2 with diffuse carcinoma in situ and stage Ta lesions had persistent stage Ta disease and 2 with diffuse carcinoma in situ and focal stage T2 disease had disappearance of the carcinoma in situ but persistent invasive disease at 3 months. This new light delivery system appears to be effective in the treatment of diffuse, resistant carcinoma in situ of the bladder.

Aged↗
PubMed1985

Long-term results with the Jonas malleable penile prosthesis.

Long-term assessment (mean followup 30 months) of patient-partner satisfaction and device reliability was done in 100 patients who had undergone implantation of a Jonas malleable penile prosthesis. Evaluation included an extensive questionnaire and radiographs of the prosthesis. The long-term satisfaction rate was 84 per cent and 2 patients had wire fractures. A life-table analysis was performed with the data from 78 patients who had completed the questionnaire and who had a radiograph of the original implanted device. The probability of having a device without mechanical failure at 23.6 months was estimated to be 96.1 per cent. Thereafter, no additional mechanical failures occurred in units followed up to a maximum of 44 months.

Actuarial Analysis↗
PubMed1985

Percutaneous removal of kidney stones: review of 1,000 cases.

We report the results of 1,000 consecutive patients who underwent percutaneous removal of renal and ureteral stones. Removal was successful for 98.3 per cent of the targeted renal stones and 88.2 per cent of the ureteral stones. Complications, evolution and technique are discussed. Percutaneous techniques are an effective way to handle the majority of renal calculi and these techniques will continue to be important as shock wave lithotripsy becomes more widespread in the United States.

Blood Transfusion↗
PubMed1985

Intravesical thiotepa and mitomycin C treatment immediately after transurethral resection and later for superficial (stages Ta and Tis) bladder cancer: a prospective, randomized, stratified study with crossover design.

In a prospective, randomized, stratified study with crossover design the effect of thiotepa was compared to that of mitomycin C when each was instilled intravesically immediately at the end of complete removal of superficial bladder cancer (stages Ta and Tis) and later on tumor recurrence. The 3-month and 1-year rates free of recurrence were 93 and 78 per cent, respectively, for thiotepa (41 patients), and 97.6 and 67.1 per cent, respectively, for mitomycin C (42 patients) (p equals 0.6). On crossover (5 patients to thiotepa and 9 to mitomycin C) at 1 year 60 per cent of the patients receiving thiotepa secondarily and 51.9 per cent of those receiving mitomycin C secondarily were free of recurrence (p equals 0.52). Therefore, both drugs are equally effective in reducing bladder tumor recurrence. Future comparative studies should continue to include thiotepa as a standard by which the efficacies of other agents are judged.

Adult↗