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M C Benson

Publications and source records attributed to M C Benson.

At least 37 records · Page 2Linked to original sources
PubMed1999

Prostate-specific antigen and other serum markers: current concepts from the World Health Organization Second International Consultation on Prostate Cancer.

Serum prostate-specific antigen is credited with dramatic advances in the early detection, screening, and management of men with prostatic carcinoma. There has been more than a twofold increase in the number of men diagnosed during the last decade, and prostate cancer has emerged as the most common non-skin cancer and the second leading cause of cancer death in men. This report summarizes the history and current status of prostate-specific antigen and other serum markers, incorporating consensus opinions from the Second International Consultation on Prostate Cancer held in Paris in June 1999.

Age Factors↗
PubMed1998

Oral bropirimine immunotherapy of bladder carcinoma in situ after prior intravesical bacille Calmette-Guérin.

OBJECTIVES: Bropirimine is an oral immunomodulator that has demonstrated anticancer activity in transitional cell carcinoma in situ (CIS) in both the bladder and upper urinary tract. Activity also has been documented in patients after prior therapy with bacille Calmette-Guérin (BCG). To more accurately estimate bropirimine's efficacy in BCG-resistant bladder CIS, a Phase II trial was performed. A separate analysis was performed in additional patients intolerant of BCG toxicity. METHODS: Patients received bropirimine 3.0 g/day by mouth for 3 consecutive days, weekly, for up to 1 year. Bladder biopsies and cytologic examination were performed quarterly. Complete response (CR) required negative biopsy and cytology results. RESULTS: Twenty-one of 86 patients entered were not evaluable. CR was seen in 21 (32%; 95th percentile confidence interval [CI], 21% to 44%) of 65 evaluable patients, including 14 (30%, CI 17% to 43%) of 47 BCG-resistant, and 7 (39%, CI 16% to 61%) of 18 BCG-intolerant patients. Overall, by intent-to-treat analysis, CR was thus seen in 21 (24%) of 86 subjects. Most BCG-resistant patients were failures to BCG without relapse, and had received 12 to 36 (median 12) BCG treatments; intolerant patients had received 4 to 11 treatments (median 6). Response duration ranged from 65 to 810 days, with median not yet reached (but greater than 12 months). Thirteen (15%) of 86 stopped bropirimine due to toxicity. Progression to invasive or metastatic disease during or immediately after therapy was documented in only 4 patients (6%), all nonresponders. CONCLUSIONS: Bropirimine may be an alternative to cystectomy for some patients with bladder CIS who have failed or have not tolerated BCG. Further evaluation to improve responses and durability is warranted.

Adjuvants, Immunologic↗
PubMed1998

Urinary continence after radical prostatectomy: the Columbia experience.

PURPOSE: We determine the incidence of urinary incontinence after radical prostatectomy and the factors that may influence this incidence. MATERIALS AND METHODS: A total of 615 men who underwent radical retropubic prostatectomy performed by 1 of us (C. A. O. or M. C. B.) at our center between 1988 and 1996 were mailed a questionnaire regarding preoperative and postoperative voiding habits. Data collected included preoperative and postoperative continence status, interval to postoperative continence status, associated urinary symptoms, willingness to undergo radical prostatectomy again if given the chance and additional postoperative procedures. Patient age, date of surgery and duration of followup were also noted. RESULTS: Of the 615 patients 480 (78.2%), a mean of 62.6 years old, responded to the questionnaire. Mean followup was 3.3 years (range 1 to 8.8). Continence was defined as no regular use of pads. Of the respondents 91.8% were considered continent, 92% had achieved final continence status by 6 months postoperatively, 10.6% required 1 or more additional procedures related to urinary control and 90% would undergo surgery again if given the chance. Of the patients considered incontinent postoperatively 44% had associated urgency. Age, year of surgery and preoperative urinary leakage or post-void dribbling had no significant impact on postoperative continence status. CONCLUSIONS: Using an anonymous self-administered questionnaire we found an 8.2% incontinence rate after radical prostatectomy. This rate was similar to that in large, single institutional studies in which physician interview was used to elicit responses but significantly less than that in a national sample of Medicare patients also given a self-administered questionnaire. With minimal potential for adverse consequences in the hands of experienced surgeons, radical prostatectomy remains well tolerated with excellent patient satisfaction.

Aged↗
PubMed1998

The role of tumor biomarkers as predictors of serum PSA recurrence after radical prostatectomy.

Tumor biomarkers (p53, bcl-2, Ki-67, and RT-PCR) were reviewed in the literature for their ability to predict prostate-specific antigen (PSA) biological recurrence after radical prostatectomy. All of them are strongly associated with PSA recurrence on univariate analysis. p53 seems to be better than current predictors, such as stage, grade, and positive surgical margins on multivariable analysis; further studies need to confirm bcl-2 and Ki-67 as better predictors of PSA recurrence. However, most of these studies were performed on radical prostatectomy specimens and will need to be confirmed on the preoperative prostate biopsy. The RT-PCR assay was strongly correlated with PSA recurrence and was one of the two best preoperative PSA recurrence predictors with serum PSA.

Biomarkers, Tumor↗
PubMed1997

Detection of circulating prostate carcinoma cells via an enhanced reverse transcriptase-polymerase chain reaction assay in patients with early stage prostate carcinoma. Independence from other pretreatment characteristics.

BACKGROUND: Circulating prostate cells can be detected in the venous blood of patients with clinically localized prostate carcinoma by applying reverse transcriptase-polymerase chain reaction (RT-PCR) techniques using primers specific for the prostate specific antigen (PSA) gene. This study evaluates whether the detection of circulating cells correlates with established prognostic factors, treatment, and pathologic stage. METHODS: Two hundred and twenty-seven patients with clinically localized adenocarcinoma of the prostate had an RT-PCR assay performed as part of their staging evaluation. No treatment decisions were made on the basis of the RT-PCR results. Of these, 156 patients were treated with radical prostatectomy (RP) and 71 with radical external beam radiotherapy (EBRT). Forty-eight patients were treated with hormonal therapy prior to RP (n = 39) or EBRT (n = 9). The prognostic factors analyzed for their relationship to RT-PCR were clinical stage, pretreatment serum PSA levels, Gleason score of the biopsy specimen, and Gleason score of the surgical specimen. An analysis of the relationship between treatment and RT-PCR results was also performed. Multivariate logistic regression analysis of predictors of RT-PCR positivity was performed as well. In addition, univariate and multivariate analyses of predictors of pathologic stage, including RT-PCR, were performed. RESULTS: Sixty-one patients (26.9%) had a positive RT-PCR assay. There was no relationship between clinical stage, pretreatment PSA, biopsy Gleason score, or surgical Gleason score and RT-PCR positivity. In univariate analysis, patients treated with RP had a higher rate of RT-PCR positivity than patients treated with EBRT (P = 0.054). However, in multivariate logistic regression analysis no factor, including treatment with RP, was a significant predictor of RT-PCR positivity. RT-PCR and pretreatment PSA predicted pathologic stage in univariate and multivariate analyses (P < 0.0001 and P = 0.002, respectively). CONCLUSIONS: The detection of circulating prostate cells using RT-PCR occurs in approximately 25% of early stage prostate carcinoma patients and is independent of other established prognostic factors. In addition, a positive RT-PCR assay is a strong predictor of pathologic upstaging in patients with clinically organ-confined disease.

Analysis of Variance↗
PubMed1997

Pretreatment prostate specific antigen doubling times: use in patients before radical prostatectomy.

PURPOSE: We determined whether pre-radical prostatectomy prostate specific antigen (PSA) doubling time could predict pathological stage at radical prostatectomy or PSA failure postoperatively. We also sought to compare PSA doubling times from men with prostate cancer treated with radical prostatectomy to a group treated with radiation therapy. MATERIALS AND METHODS: Detailed followup was available for 150 patients with clinically localized prostate cancer who underwent radical prostatectomy from January 1993 to August 1995. PSA doubling time was calculated for all patients with 3 or more pre-radical prostatectomy PSA levels using linear regression. We assessed the association between PSA doubling time and PSA failure, pathologic stage at radical prostatectomy, final PSA before treatment and Gleason score. We compared our PSA doubling time values and distribution to a published series of patients with prostate cancer who had undergone radiation therapy. RESULTS: A total of 56 patients had 3 or more PSA values before treatment. Median followup was 17.3 months. PSA doubling time did not correlate with PSA failure, final PSA or Gleason score, but it did with pathological stage at radical prostatectomy (p = 0.0035 for positive margins, p = 0.025 for positive seminal vesicles). Our PSA doubling time and PSA failure rates did not differ from the radiation therapy population with similar followup times. CONCLUSIONS: Although studies from the radiation literature have shown PSA doubling time to be useful in predicting PSA failure after treatment for prostate cancer, our results do not confirm this finding. We did find a correlation with pathologic stage at radical prostatectomy, and so longer followup with more patients may confirm this in the future. We also found no significant differences in PSA doubling time between our patients and a group treated with radiation. At least for this parameter, patients with prostate cancer referred for radical prostatectomy and radiation therapy may be similar.

Aged↗
PubMed1997

Re-examining the role of prostate-specific antigen density in predicting outcome for clinically localized prostate cancer.

OBJECTIVES: To evaluate the prognostic significance of prostate-specific antigen density (PSAD) in clinically localized prostate cancer and determine whether this index is independent of or superior to prostate-specific antigen (PSA) in predicting outcome of patients treated with external beam radiotherapy. METHODS: Between January 1989 and December 1993, 175 evaluable patients with clinically localized prostate cancer received definitive radiotherapy using computed tomography (CT)-guided conformal techniques. PSAD was defined as the ratio of the pretreatment serum PSA to the prostate volume measured from CT treatment planning scans by one investigator. All PSA values were determined using the Hybritech assay. Biochemical failure was defined as two consecutive elevations in PSA separated by at least 3 months and a final PSA value greater than 1 ng/mL. RESULTS: Multivariate analysis including PSA and Gleason score revealed both to be statistically significant predictors of biochemical disease-free survival (P = 0.048 and P < 0.001, respectively). PSAD did not achieve significance on regression analysis. A direct multivariate analysis including PSA and PSAD required dichotomization in order to reduce high correlation. This analysis demonstrated a relative risk (RR) for failure of 1.27 (NS) for high PSA versus low PSA compared with a RR of 1.20 (NS) for high PSAD versus low PSAD. A regression model containing all three variables indicated only the Gleason score as significant in predicting biochemical failure. CONCLUSIONS: These data do not suggest that PSAD is either an independent prognostic factor or a stronger discriminant of outcome than PSA in patients with clinically localized prostate cancer treated with definitive external beam radiotherapy. Larger patient numbers with longer follow-up data, use of a clinical end point, or an analysis restricted to the appropriate subgroup may demonstrate the utility of PSAD in the future.

Adenocarcinoma↗
PubMed1996

Bropirimine immunotherapy of upper urinary tract carcinoma in situ.

OBJECTIVES: Bropirimine has been shown to be effective in treating approximately 50% of patients with carcinoma in situ (CIS) of the bladder in recent clinical trials. Patients with upper tract CIS were treated with bropirimine to determine whether this oral drug might be effective in that setting. METHODS: Twenty-four patients with negative radiographic findings and positive cytologic evidence for upper tract CIS in one or both ureters received bropirimine (3.0 g/day orally) for 3 consecutive days each week for up to 1 year. Ureteral collection of urine or barbotage for cytologic analysis was performed quarterly thereafter. RESULTS: Ten (48%) of 21 evaluable patients had a negative ureteral cytologic analysis after 12 weeks (5 patients) or 24 weeks (5 patients). Of these 10 patients, 8 continue to have negative cytology for a period of 3 to 30 months (median, more than 9 months). In 2 patients, negative cytology reverted to positive at 6 and 9 months, respectively, during therapy. Twelve (50%) of the 24 patients reported no toxicity. Three patients stopped treatment at 2, 3, and 3 weeks due to pruritic rash, nausea and vomiting, and severe bone pain, respectively. Therapy was stopped in 1 additional patient between 4 and 5 months because of transient liver enzyme elevations, yet this patient has had a continuous negative cytologic analysis for more than 9 months. CONCLUSIONS: Orally administered bropirimine may be effective therapy for CIS of the ureter or renal pelvis, with acceptable toxicity in most patients. Further efforts to better define this activity as well as the possible need for maintenance or intermittent long-term therapy are warranted.

Adjuvants, Immunologic↗
PubMed1996

Giant multilocular cystadenoma of the prostate.

Giant multilocular prostatic cystadenoma is a rare clinicopathologic entity characterized by benign histology and the ability to enlarge massively. The lesion may arise from the prostate gland either in continuity with the prostatic urethra or separate from it, or it may arise as a lesion distinct from the prostate gland. Obstructive voiding symptoms occur in all reported cases. The use of preoperative radiographic evaluation, such as magnetic resonance imaging, effectively defines the lesion's benign nature and aids in planning surgical extirpation.

Aged↗
PubMed1996

Improved continence with tubularized bladder neck reconstruction following radical retropubic prostatectomy.

OBJECTIVES: Incontinence after radical retropubic prostatectomy remains a common problem. This study determines the efficacy of a tubularized bladder neck reconstruction for improving the time to continence and also the total rate of continence following radical retropubic prostatectomy. METHODS: Tubularized bladder neck reconstruction was performed in 29 patients by creating a trapezoidal-shaped anterior bladder flap and performing tubularization over a 30 F red rubber catheter prior to urethrovesical anastomosis. This flap measured approximately 5 cm at its base and 3 cm at its apex. Continence rates of these patients were compared to results of 30 randomly selected patients in whom a bladder flap was not used. RESULTS: Seven of 29 (24%) patients with tubularized bladder neck reconstruction were fully continent within 24 hours of catheter removal and 27 of 29 (93%) were fully continent by 3 months follow-up. An additional patient was continent at 6 months for a total continence rate of 28 of 29 (97%). These continence rates were significantly higher at all follow-up times than for patients in whom an anterior bladder flap was not used. One patient developed a bladder neck contracture and was successfully managed with visual urethrotomy. He is fully continent. CONCLUSIONS: Tubularized bladder neck reconstruction following radical prostatectomy may both increase the successful achievement of postoperative continence and decrease the time needed to achieve full continence without increasing morbidity.

Aged↗
PubMed1996

The role of the reverse-transcriptase polymerase chain reaction assay for prostate-specific antigen in the selection of patients for radical prostatectomy.

Prostate cells present in the peripheral circulation can be detected using an enhanced reverse-transcriptase polymerase chain reaction (RT-PCR) for prostate-specific antigen (PSA) assay. In one study, preoperative enhanced RT-PCR for PSA status was a significant predictor of surgical pathology and postoperative biomechanical recurrence. The use of RT-PCR may enhance the urologist's ability to stage potential candidates for radical prostatectomy, as the assay is a more sensitive and specific predictor of microscopic extracapsular extension than conventional staging modalities. This highly adaptable assay also may have roles in screening for recurrence and in staging other solid tumors.

Adenocarcinoma↗
PubMed1996

External beam radiation therapy does not offer long-term control of prostate cancer.

In the absence of large, contemporary, randomized series comparing external beam radiation and radical prostatectomy, definitive conclusions regarding relative efficacy are difficult to establish. This article examines series in which an objective, comparable end point was used and prostate-specific antigen (PSA) response was assessed. With follow-up of less than 5 years, PSA-based recurrence rates are similar for external beam radiation and radical surgery; however, the 10- and 15-year control rates are significantly lower in the population of patients treated with external beam radiation. The authors conclude that external beam radiation therapy as a single modality does not equal radical prostatectomy in comparably staged and followed patients.

Humans↗
PubMed1996

The use of RT-PCR for prostate-specific antigen assay to predict potential surgical failures before radical prostatectomy: molecular staging of prostate cancer.

OBJECTIVE: To assess the potential role of a recently developed reverse transcriptase-polymerase chain reaction (RT-PCR) assay for prostate-specific antigen (PSA), that detects circulating prostate cells in patients with prostate cancer, in the management of clinically localized cancer. PATIENTS AND METHODS: A total of 138 men (mean age 62.5 years, range 49-70) scheduled for radical retropubic prostatectomy had an RT-PCR assay before surgery. The results were compared with the final pathological stage of disease, the results from local imaging techniques, serum PSA levels, digital rectal examination (DRE) and Gleason score. RESULTS: Enhanced RT-PCR for PSA was the best predictor of potential surgical failures; 70% of patients with positive surgical margins or invasion into the seminal vesicle were identified pre-operatively by a positive RT-PCR assay (odds ratio = 12.0, positive predictive value = 64%, negative predictive value = 87%). RT-PCR was able to identify pre-operatively patients with adverse pathology, despite low serum PSA values (< 4.0 ng/mL). In patients with high PSA level (> 10 ng/mL), RT-PCR discriminated between potentially curable candidates and those with established extraprostatic disease. CONCLUSIONS: RT-PCR for PSA adds unique prognostic information when considering patients for radical surgery. The final role for the RT-PCR assay is as yet undefined; however, the ability to detect potential surgical failures pre-operatively using a molecular approach should have a significant impact on the management of patients with prostate cancer.

Aged↗
PubMed1996

Preoperative reverse transcriptase polymerase chain reaction for prostate specific antigen predicts treatment failure following radical prostatectomy.

PURPOSE: We previously demonstrated than an enhanced reverse transcriptase-polymerase chain reaction assay for prostate specific antigen (PSA) can predict final pathological stage in radical prostatectomy patients. The potential role of the assay in predicting serum PSA recurrence after radical prostatectomy was explored. MATERIALS AND METHODS: We evaluated 100 radical prostatectomy candidates by reverse transcriptase polymerase chain reaction preoperatively, and status was compared to serum PSA, Gleason score and final pathological results. Potential surgical failure was defined as tumor at the surgical margin or extending into the seminal vesicle. Patients were monitored postoperatively by serum PSA every 4 months. Kaplan-Meier analysis was used to evaluate the correlation between reverse transcriptase polymerase chain reaction and disease recurrence, defined as a PSA of 0.2 ng/ml. or greater. RESULTS: Enhanced reverse transcriptase polymerase chain reaction for PSA had a stronger correlation with potential surgical failure than preoperative serum PSA or Gleason score (relative risks 15.2, 5.9 and 3.2, respectively). The correlation between these modalities and PSA recurrence was evaluated during a mean followup of 13.6 months (range 5 to 26). Of 36 patients with positive reverse transcriptase polymerase chain reactions 9 had failure by PSA compared to 3 of 64 (4.7%) with negative polymerase chain reactions (p<0.0286). The relative risk for failure by reverse transcriptase polymerase chain reaction was 3.6. Gleason score and serum PSA had higher correlations with postoperative PSA elevations (relative risk 13.2 and 7.6, respectively). A Cox regression analysis model demonstrated that reverse transcriptase polymerase chain reaction for PSA can be used in conjunction with Gleason score and provides statistically significant risk information. CONCLUSIONS: Enhanced reverse transcriptase polymerase chain reaction for PSA is a statistically significant predictor of potential failure by pathological analysis and of disease recurrence by PSA. Longer followup data are required to define further the role of the assay in the management of patients with prostate cancer.

Aged↗
PubMed1996

The ileal ureter neobladder is associated with a high success and a low complication rate.

PURPOSE: Several different methods to construct a bladder substitute after cystectomy have been described. We evaluated our experience with the Studer ileal ureter neobladder during the last 5 years. MATERIALS AND METHODS: We reviewed retrospectively the results in 32 patients who underwent construction of a slightly modified ileal neobladder from that originally described. Mean followup was 25 months (range 6 to 68). RESULTS: Patients experienced few complications and only 1 required reoperation. Daytime and nighttime continence rates were 94 and 74%, respectively. One patient sustained a ureteral stricture resulting in hydronephrosis (1 of 64 renal units). CONCLUSIONS: The results reveal the ileal neobladder to be an easily constructed pouch with a low complication rate, and a high success rate in regard to continence and the establishment of adequate capacity at low pressure. Within the study period upper tract preservation was excellent. However, a 10 to 15-year followup is indicated to confirm our initial results.

Adult↗