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R G Middleton

Publications and source records attributed to R G Middleton.

At least 19 recordsLinked to original sources
PubMed2001

Outcomes for men with clinically nonmetastatic prostate carcinoma managed with radical prostactectomy, external beam radiotherapy, or expectant management: a retrospective analysis.

BACKGROUND: With a lack of data from randomized trials, the optimal management of men with nonmetastatic prostate carcinoma is controversial. The authors sought to define the outcomes of three common strategies for managing patients with nonmetastatic prostate carcinoma: expectant management, radiotherapy, and radical prostatectomy. METHODS: The authors conducted a retrospective cohort study with standardized collection of key prognostic data, including centralized assignment of Gleason grades from original biopsy specimens. Participants included all Connecticut hospitals (the expectant management cohort) and three academic medical centers in other states (the radiotherapy and surgery cohorts). Two thousand three hundred eleven consecutive men ages 55-74 years who were diagnosed during 1971-1984 with nonmetastatic prostate carcinoma and were treated at the participating sites were included. RESULTS: Kaplan-Meier estimates with 95% confidence intervals (95% CI) of overall survival at 10 years for each cohort were as follows: expectant management cohort, 42% of patients (95% CI, 38-46%); radiotherapy cohort, 52% of patients (95% CI, 46-58%); and radical prostatectomy cohort, 69% of patients (95% CI, 67-71%); for disease specific mortality, the estimates were as follows: expectant management cohort, 75% of patients (95% CI, 71-79%); radiotherapy cohort, 67% of patients (95% CI, 61-73%); and radical prostatectomy cohort, 86% of patients (95% CI, 84-88%). There were large differences in distributions of important prognostic factors among men in the different treatment groups. CONCLUSIONS: These data provide precise estimates of the outcomes of patients who have been treated with different modalities for nonmetastatic prostate carcinoma in the recent past. Direct comparisons of outcomes between treatment groups are inadvisable because of the different characteristics of patients who select these alternative management strategies.

Aged↗
PubMed2000

Heritability of prostate-specific antigen and relationship with zonal prostate volumes in aging twins.

Both benign prostatic hyperplasia and prostate-specific antigen (PSA) have been shown to increase with age and with prostate volume in men, but the influence of heredity on these relationships is not completely understood. This study has two aims: 1) to investigate the inter-relationships of age, PSA, and various zonal measurements in the prostate; and 2) to assess the impact of heritable influences on total PSA. Eighty-four monozygotic twin pairs and 83 dizygotic twin pairs were studied, and serum total PSA, free PSA, and PSA-alpha1-antichymotrypsin were measured. Their prostate volumes [total (TV), transition zone (TZ), and peripheral zone) were quantitated using transrectal ultrasound. Total PSA is significantly correlated with all zonal prostate measurements (TZ, peripheral zone, TV, and TZ/TV) and with age. When linear regression was applied, only age and TZ were retained in the final model. The proportion of variability in total PSA explained by these two factors, however, is below 24%. In contrast, estimates of heritability show that approximately 45% of the variability in total PSA can be explained by inherited factors. Whereas age and TZ are linearly related to total PSA, their influence is much less than that of familial and genetic factors. It is uncertain whether these factors predispose also to prostate cancer or if they are independent of those, whether they confound the accuracy of using total serum PSA level as a diagnostic tool.

Adult↗
PubMed1999

Heritability of the symptoms of benign prostatic hyperplasia and the roles of age and zonal prostate volumes in twins.

OBJECTIVES: Both benign prostatic hyperplasia and lower urinary tract symptoms (LUTS) have been shown to increase with age in men, but a causal relationship between prostate volume and symptoms has not been established. This study had two aims, to investigate the inter-relationships of age, symptoms, and various zonal measurements in the prostate and to assess the impact of heritable influences on symptom score. METHODS: Eighty-three monozygotic twin pairs and 83 dizygotic twin pairs were studied to determine age and LUTS as assessed by the American Urological Association symptom score. Their prostate volumes (total, transition zone, and peripheral zone) were measured by transrectal ultrasound. RESULTS: There was significant evidence of pairwise correlation between transition zone and symptom score (P = 0.04) and between age and symptom score (P = 0.03). Age also showed significant correlation with all volume measurements. Heritability appears to account for 82.6% of the variability in symptom score in men older than 50 years. CONCLUSIONS: This study provides evidence that age and transition zone volume play a role in LUTS, but also that their influence is not strong. Estimates of heritability suggest that hereditary factors contribute substantially to LUTS.

Adult↗
PubMed1999

Have complication rates decreased after treatment for localized prostate cancer?

PURPOSE: The American Urological Association Prostate Cancer Clinical Guidelines Panel reviewed 12,501 publications on prostate cancer from 1955 to 1992 to determine whether the complication rates of external beam radiation therapy, interstitial radiotherapy and radical prostatectomy have decreased. MATERIALS AND METHODS: Complications reported in at least 6 series, study duration and sample sizes were extracted. Year specific study weighted mean patient ages and complication rates were computed. Regression analysis was performed of the study year on weighted mean patient age and complication rate. RESULTS: Study year had a significant effect on mean patient age and rate of the majority of complications examined. Data indicated a gradual increase in study patient age and a simultaneous decrease in complications from 1960 to 1990. CONCLUSIONS: Complication rates in the treatment of localized prostate cancer have decreased during the last 20 to 40 years. This decrease occurred despite evidence that the average age of treated patients had increased during the same period.

Aged↗
PubMed1998

Effects of design changes on cemented tapered femoral stem fixation.

The effects of matte finish and modularity on loosening of tapered stems using the same cementing technique were studied prospectively. In 80 patients, 82 cemented Exeter primary stems were implanted at total hip revision by one surgeon using the same surgical and cementing technique throughout the series. The polished stems behaved differently than the matte surfaced stems behaved. Polished stems subsided in the cement mantle an average of 1 mm at 2 years after implantation, but without subsequent loosening of stems at as long as 12 years after implantation. Matte surfaced stems with metal centralizers had a higher loosening rate, and loss of fixation at the prosthesis to cement interface was identified as an early sign of loosening of these stems. At a mean 6-year followup, there were no revisions nor was there radiographic evidence of loosening of the polished modular stems. It is concluded that matte finish results in increased loosening of tapered stems but the introduction of modularity did not.

Aged↗
PubMed1998

Loosening of matt and polished cemented femoral stems.

We have compared prospectively the incidence of loosening of 20 femoral stems with a matt surface with that of 20 polished stems of an otherwise identical tapered, non-modular design of Exeter hip replacement. The stems were inserted using the same technique at operation and radiographs showed no difference in the adequacy of the cement mantle or of fixation. All the patients were reviewed regularly and none was lost to follow-up. After a minimum follow-up of nine years, four matt but no polished stems had been revised for aseptic loosening. Polished stems subsided slightly within the cement mantle early, but did not loosen.

Acetabulum↗
PubMed1997

Age, genetic, and nongenetic factors influencing variation in serum sex steroids and zonal volumes of the prostate and benign prostatic hyperplasia in twins.

BACKGROUND: We have observed that hereditary and environmental factors have a substantial influence on the plasma content of sex steroids in normal male twins and in men of families with prostatic disease. METHODS: The contribution of genetic and nongenetic familial factors on the variation of plasma sex steroid concentrations and of the volume of zones of the prostate measured by transrectal ultrasound (TRUS) has now been investigated in pairs of male monozygotic (MZ) and dizygotic (DZ) twin pairs between age 25-75 years. Bioelectric impedance permitted quantitation of body fat, lean body mass, and water. Morphometrics and testicular volume were also determined. RESULTS: The intraclass correlation (rI) was > 0.40 for the variation of the total volume (TV), the transition zone (TZ), the peripheral zone (PZ), and the ratio of TZ/PZ in both MZ and DZ twins, and heredity affected 22% of the variation of the PZ and TZ and 30% of the ratio of TZ/PZ. None of the TV and environmental factors influenced the remainder of the variation. Heredity accounted for 25% or more of the variation of dihydrotestosterone (DHT), and the ratios of DHT/testosterone (T), estradiol (E2)/T, androstanediol glucuronide, sex hormone-binding globulin (SHBG)-bound T, T/SHBG, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and dehydroepiandrosterone sulfate (DHEA-S). In MZ twin pairs the variation of the volumes of the prostate became greater with age. In contrast, the variation of the sex hormone concentrations did not show greater variation with age. Heredity also affected > 30% of the variation for waist measurement, weight, body fat, body mass, water and lean body mass, body mass/fat, and testicular size. CONCLUSIONS: Our results indicated that both MZ and DZ twin pairs had zonal prostate volumes more like their twin pair than like unrelated twins. However, nongenetic factors exerted stronger influences than genetic factors on zonal volumes of the prostate. In contrast, hereditary factors had stronger influences on determining the variation of many sex hormones and morphometric characteristics than did nongenetic factors.

Adult↗
PubMed1997

Female urologists: a growing population.

PURPOSE: Although urology continues to be a male dominated field, the participation and influence of women within the specialty are growing. In the United States as of July 1995, 56 of 1,339 urology residents (4.2%) and 97 of 8,227 board certified urologists (1.2%) were women. The demographics of this group, including age, board certification, fellowship experience and practice patterns, are unknown. Mentorship and motivations leading to urology as a specialty choice for women are also unreported. MATERIALS AND METHODS: We surveyed 161 female urologists by mail. RESULTS: Of the women surveyed 80% responded. Female urologists tend to be young and board certified, 39% are fellowship trained and 22% hold full-time academic positions. Women were discouraged from selecting urology as a specialty because of gender. Many women had male (59%) or no (35%) mentors throughout the training years, 70% were married and 44% had children. Of the 25 respondents who had children during residency most (84%) felt supported by the program director and resident peers. Despite obstacles 94% of female urologists would encourage other women to enter urology. CONCLUSIONS: Female urologists are young, well educated and career oriented. Although most did not have mentors during training, there is a high level of job satisfaction and low attrition after training.

Female↗
PubMed1997

Prostate size in hypogonadal men treated with a nonscrotal permeation-enhanced testosterone transdermal system.

OBJECTIVES: This study examined the effects of testosterone replacement using a nonscrotal testosterone transdermal (TTD) system on prostate size and prostate-specific antigen (PSA) levels in hypogonadal men. METHODS: As part of an open-label, multicenter study, prostate volume as measured by transrectal ultrasound and PSA were assessed in 29 hypogonadal men during treatment with intramuscular testosterone enanthate (+TE), followed by 8 weeks of androgen withdrawal (-T), and then during 1 year of therapy with Androderm Testosterone Transdermal System, a nonscrotal permeation-enhanced TTD system (+TTD). RESULTS: Mean prostate volume decreased significantly from the +TE period (17 g) compared with the -T period (14 g) (P < 0.001). Prostate volume increased significantly from the -T period compared with the +TTD period (18 g) (P < 0.001). Maximum prostate size, comparable to that measured during +TE (P = 0.125), was reached by month 3 of +TTD therapy; prostate volume did not increase further during the remaining 9 months of +TTD therapy. Prostate volume correlated with age (P < 0.01) during all three periods of observation (+TE: r = 0.69; -T: r = 0.64; and +TTD: r = 0.55). No patient developed symptomatic benign prostatic hyperplasia during the treatment period. PSA levels decreased during androgen withdrawal compared with levels measured during +TE treatment (P < 0.001) and rose with resumption of androgen therapy with TTD (P < 0.006). However, PSA levels during +TTD replacement remained significantly lower (P < 0.001) than during +TE replacement. CONCLUSIONS: Physiologic testosterone replacement in hypogonadal men was achieved using the TTD system. Prostate size during therapy with TTD was comparable to that reported for normal men. In these men treated with TTD, PSA levels were also within the normal range.

Administration, Cutaneous↗
PubMed1997

Effects of age and sex hormones on transition and peripheral zone volumes of prostate and benign prostatic hyperplasia in twins.

Benign prostatic hyperplasia has been shown to increase with age and be influenced by sex hormones. The relationship between aging and hormonal influences on growth of zones of the prostate is unresolved. We studied the relationship of age and sex hormones on volume of prostate zones in 214 male twins between 25 and 75 yr old. Volumes of the total prostate (TV), transition zone (TZ), and peripheral zones (PZ) were measured using transrectal ultrasound, and sex steroid concentrations were measured using RIA. Using transformed data corrected for age, TV (r = 0.54, P < 0.00001), TZ (r = 0.58, P < 0.00001), and PZ (r = 0.39, P < 0.00001) volumes increased with age. However, the PZ volume rose more rapidly than the TZ before age 50, and TZ showed a steeper increase after age 50 yr than the PZ volume. The TZ, PZ, and ratio TZ/PZ correlated significantly (r = 0.87, 0.90, and 0.52, respectively; P < 0.00001). After a TV exceeded 30 g, the rise of the PZ became attenuated, and the slope of the TZ became steeper. Age-adjusted sex hormone concentration was not evaluated in men with larger prostate volumes. Men with American Urological Association symptom scores above 10 had significantly (P < 0.001) larger total prostate volume (TV) and TZ volume, but not PZ volumes, than men with scores below 10. Prostate volumes correlated inversely with age-adjusted serum testosterone (T), dihydrotestosterone, sex hormone binding globulin, and sex hormone binding globulin-bound T concentrations. These results demonstrate that before age 50 yr or before a prostate weight exceeds 30 g, prostate growth may be mainly from enlargement of the PZ and after age 50, the TZ. In addition, elevated T and dihydrotestosterone concentrations do not predispose men to prostate enlargement or symptoms of benign prostatic hyperplasia.

Adult↗
PubMed1997

Wide excision (nonnerve sparing) radical retropubic prostatectomy using an initial perirectal dissection.

PURPOSE: Positive surgical margin rates after radical retropubic prostatectomy are reported to range from 25 to 50% in contemporary series. We report on 53 nonnerve sparing radical retropubic prostatectomies performed with attention paid to extending the margin of attached periprostatic tissue. This was accomplished primarily by initial perirectal release of periprostatic tissues at the level of longitudinal rectal fibers posterior and lateral to the prostate. This perirectal release ensures that maximal quantities of periprostatic tissue will remain with the prostate specimen and will not be attenuated or sheared away at subsequent stages of the procedure. MATERIALS AND METHODS: Pathological material was examined for capsular penetration and surgical margins using transverse whole mount sections of the prostate at 4 to 5 mm. intervals. Patients were followed at regular intervals with physical examinations and serum prostate specific antigen (PSA) determinations. RESULTS: The series consisted of 6, 5, 14 and 28 cases of clinical stages T1b, T1c, T2a and T2b cancer, respectively. Mean PSA was 10.0 ng./ml. and mean Gleason score was 5.9. Capsular penetration was observed in 47 of 53 cases (89%) and positive surgical margins were noted in 7 (13%). With a median followup of 3.61 years 2 patients experienced PSA defined recurrence. CONCLUSIONS: We believe that positive surgical margin rates may be decreased when technical modifications are directed at increasing the amount of periprostatic tissue excised with the surgical specimen.

Follow-Up Studies↗
PubMed1996

Occlusion of the external iliac vein by cement.

The case of an 80-year-old woman who sustained occlusion of the external iliac vein by methyl methacrylate cement following total hip arthroplasty is presented. The cement was removed via a pelvic approach without the need for revision of the acetabular cup and led to resolution of her symptoms.

Aged↗
PubMed1996

Repair of rectourinary fistulas using a posterior sagittal transanal transrectal (modified York-Mason) approach: an update.

PURPOSE: We report our experience with posterior sagittal, transanal, transrectal repair of rectourinary fistulas. MATERIALS AND METHODS: A total of 16 fistula repairs was done in 15 patients. RESULTS: Of the fistulas 13 occurred after a variety of prostatic procedures, 1 after Y-V plasty and 1 after pelvic trauma (2 repairs were attempted in the latter case). Six patients underwent repair without colostomy. No patient experienced fecal or anal complications and all repairs were successful. CONCLUSIONS: Our surgical approach for repair of rectourinary fistulas is simple, effective, associated with minimal morbidity and cost-effective.

Fractures, Bone↗
PubMed1995

Effects of age, sex steroids, and family relationships on volumes of prostate zones in men with and without prostate cancer.

Benign prostatic hyperplasia (BPH) and prostate cancer commonly occur together. This suggests that common familial, hormonal, and environmental factors contribute to their development. In men at risk for the development of prostate cancer (at 40 men in 19 families) and aged-matched unrelated controls (n = 46), we have determined whether familial factors, age, and blood hormone concentrations are related to the transition zone (TZ), peripheral zone (PZ), or total volume of the prostate measured by transrectal ultrasound (TRUS). We determined that the influences of age, prostate cancer (n = 15), and familial status did not significantly affect the relationships reported. Therefore, data from all groups were combined for this study. TZ correlated positively with age (P = 0.003) after controlling for family status, but total prostate volume correlated insignificantly with age (P = 0.08). In addition, the ratio of TZ to PZ volumes also correlated significantly with age in the control group (r = 0.27, P = 0.014). Both TZ and PZ volumes correlated highly (r = 0.91, P < 0.0001, n = 86) with total volume. In addition, total volume correlated significantly (r = 0.71, P < 0.001) with the ratio of the TZ/PZ volumes, which also correlated significantly with each other (r = 0.61, P < 0.0001, n = 86). In contrast to the increase of TZ volume related to total prostate volume, PZ volume declined compared with total volume. Prostate volumes up to 50 ml are predominated by the PZ and above 50 ml by the TZ, which may compress and shrink the PZ. Both TZ and total prostate volume correlated positively with serum estrone concentrations (P = 0.04 and P = 0.003, respectively). These results suggest that the risk of prostate cancer does not contribute to generalized overgrowth of the prostate, including the TZ. However, estrogens and age strongly influence TZ but not PZ volume. Both PZ and TZ volumes rise together until the prostate exceeds 50 ml, when the growth of the TZ appears to exceed the PZ and then to compress it.

Aged↗