Use of endorectal MR imaging to predict prostate carcinoma recurrence after radical prostatectomy.

PURPOSE: To determine the ability of endorectal magnetic resonance (MR) imaging to help predict postprostatectomy disease recurrence and, thereby, patient outcome. MATERIALS AND METHODS: The authors evaluated 116 patients referred for prostate MR imaging during 1991 and 1992 who subsequently underwent radical prostatectomy and for whom follow-up data through 1996 could be obtained. The MR reports, clinic charts, and pathology reports were reviewed. Disease recurrence was established by means of detectable levels of serum prostate-specific antigen (PSA) after surgery. RESULTS: Thirty-four patients (29%) had postoperative disease recurrence. Patients with recurrence had higher preoperative PSA values (P < .0001). These patients also more frequently had positive surgical margins (P = .0005), transcapsular tumor spread (P < .0001), seminal vesicle involvement (P = .0012), and tumors of advanced stage (P < .0001) and high grade (P = .0058). Of 13 patients whose MR examinations showed definite extracapsular disease, eight (62%) had disease recurrence. The recurrence rate when MR imaging indicated limited disease (24%) was similar to that when MR imaging showed possible microscopic extension (27%). An MR finding of definite extracapsular disease was 24% sensitive and 94% specific for the prediction of disease recurrence. CONCLUSION: MR imaging findings of definite extracapsular spread of disease helped predict prostate tumor recurrence with high specificity, although with low sensitivity.

Limitations of craniocaudal thallium-201 and technetium-99m-sestamibi mammoscintigraphy.

UNLABELLED: Previous studies with 201Tl and 99mTc-sestamibi (MIBI) have used large field of view (LFOV) cameras not optimized for breast imaging. The purpose of this study was to compare these agents and to determine if a small field of view (SFOV) camera designed to minimize the camera-to-breast distance could improve tumor detection. METHODS: A 28-cm (SFOV) camera was fitted with slant-hole and diverging collimators to perform craniocaudal scintigraphy for direct comparison with mammography. Of the 46 patients studied, 20 had 201Tl imaging alone and 26 had combined 201Tl and MIBI imaging. LFOV (40 cm) breast and axillary images also were obtained. Visual and quantitative analyses of tumor uptake were performed. RESULTS: The SFOV camera with nonparallel collimation showed variable 201Tl and MIBI normal breast activity. This was partly due to significant scatter from cardiac and abdominal activity. Overall, 201Tl had a sensitivity of 53%, which was 67% for tumors > or = 1.5 cm and 20% for tumors < or = 1.5 cm. MIBI sensitivity was 90% (9/10) for lesions > or = 1.5 cm. Specificity was 93% for 201Tl and 83% for MIBI. There was no significant difference in 201Tl (1.76 +/- 0.55) and MIBI (1.82 +/- 0.95) tumor uptake ratios (p = 0.75). CONCLUSION: Technetium-99m-MIBI was more sensitive than 201Tl for imaging lesions > or = 1.5 cm. Craniocaudal positioning minimized the camera-to-breast distance but did not increase 201Tl detection of tumors < 1.5 cm and increased background breast activity due to scatter.