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P Holtz

Publications and source records attributed to P Holtz.

At least 19 recordsLinked to original sources
PubMed1992

Efficacy of prostate-specific antigen and magnetic resonance imaging in staging stage C adenocarcinoma of the prostate.

OBJECTIVES: The authors compared the two most common presurgical tests now used for the preoperative staging of adenocarcinoma of the prostate, prostate-specific antigen (PSA) and magnetic resonance imaging (MRI). METHODS: One hundred consecutive radical retropubic prostatectomy patients were imaged at 1.5 Tesla before surgery with routine T1-weighted and T2-weighted transaxial images. The images were analyzed by two experienced radiologists for evidence of extracapsular disease. Radiologists rated each gland on a scale of 0 to 100 for the percentage likelihood of extracapsular disease based on its MRI appearance. Receiver operator characteristic (ROC) curves were plotted, and areas were calculated for the two radiologists and the preoperative PSA values. RESULTS: Comparison of the areas of the ROC curves generated from the two radiologists and those from the preoperative PSA values showed no statistical difference. CONCLUSIONS: In this series, radiologic interpretation of body coil MRI studies in those patients chosen for a radical retropubic prostatectomy was no better in staging adenocarcinoma of the prostate than simply using the preoperative PSA values.

Adenocarcinoma↗
PubMed1992

MR imaging in adenocarcinoma of the prostate: interobserver variation and efficacy for determining stage C disease.

Patients with adenocarcinoma of the prostate confined to the gland (stage B) are candidates for a potentially curative surgical procedure (radical retropubic prostatectomy). However, patients with adenocarcinoma that penetrates the capsule or invades the seminal vesicles (stage C) are no longer considered good candidates for surgical cure of their disease. The purpose of this study was to compare the ability of four radiologists to detect stage C disease on MR images and to evaluate interobserver variability. One hundred consecutive MR studies of the prostate were reviewed independently by four radiologists to determine whether the cancer was stage C (capsule penetration or seminal vesicle invasion by tumor). A radical prostatectomy was performed in each case, and careful histologic assessment was made of the prostatic capsule and seminal vesicles for any evidence of stage C disease. The sensitivity, specificity, and accuracy (true-positive + true-negative/100 patients) in detecting stage C disease were calculated for each of the four readers. Four receiver-operating-characteristic curves were generated and compared by means of the univariate z score. Percentage agreement was calculated for five specific areas of the prostate on MR images, and observations made by the best reader were compared with the other three to help determine interreader variability. The results showed that the sensitivity and specificity of MR imaging in detecting stage C disease ranged from .24 to .61 (mean, .48) and .49 to .79 (mean, .66), respectively. The accuracy of MR imaging ranged from .47 to .61 (mean, .55). The univariate z score test showed that one of the readers significantly differed from the other three. The average percentage agreement between that reader and the other three was 70% for the five separate anatomic regions. This study shows that considerable interobserver variation exists in the interpretation of MR images for staging cancer of the prostate. The average accuracy among four radiologists in determining the presence of stage C adenocarcinoma of the prostate from MR images was only slightly above a chance guess at .55.

Adenocarcinoma↗
PubMed1983

Laser surgery in podiatric medicine--present and future.

Laser surgery in podiatric medicine is now in its most formative stages. Foot surgery lends itself to the utilization of the laser technique very readily. At the present time the laser is utilized in foot surgery at Sinai Hospital in Detroit for eradication of plantar verrucae, for excision of Morton's neuroma, for common nail pathology such as ingrown borders and traumatic ram's horn nails, and for correction of mycotic nail plates.

Adult↗
PubMed1970

[Ludwig Lendle].

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Journal Article↗