Pelvic CT findings after radical prostatectomy.

OBJECTIVE AND METHODS: To evaluate the spectrum of pelvic CT findings in patients who have had radical prostatectomy, we retrospectively evaluated the pelvic CT of 17 patients after surgery for prostate cancer. All patients were thought to be clinically free of local recurrence of carcinoma. RESULTS: The bladder base was retropubic in 100%, the levator sling was well delineated in its entirety in only 88%, and fat was clearly demonstrated between the rectum and bladder base in only 44%. Unsuspected findings in this group included soft tissue density structures in the resected bed of the seminal vesicles (88%) and a transversely oriented, soft tissue density bar between the bladder base and rectum (53%). A variety of symmetric abnormalities are commonly seen on postprostatectomy pelvic CT. CONCLUSION: Seminal vesical-like soft tissue structures are routinely visualized, and a horizontal bar of soft tissue in the rectovesical space is commonly demonstrated. These structures should not be confused with local tumor recurrence.

Reactive soft-tissue mass associated with osteoid osteoma: correlation of MR imaging features with pathologic findings.

The authors retrospectively reviewed three cases of histologically documented osteoid osteoma in which magnetic resonance (MR) imaging was performed prior to surgical excision. In all three cases, MR imaging demonstrated abnormal signal intensity characteristics, and use of gadopentetate dimeglumine resulted in enhancement. These findings correlated with a reactive soft-tissue mass with myxomatous change, as well as with cell-depleted, juxtanidal bone marrow that contained proteinaceous material. These MR imaging findings can easily be confused with those of a malignant tumor or osteomyelitis.

Solitary breast papilloma: comparison of mammographic, galactographic, and pathologic findings.

OBJECTIVE: Our purpose was to determine the mammographic/galactographic features of solitary breast papillomas and to correlate these features with the pathologic findings. MATERIALS AND METHODS: Retrospective review of pathology files revealed 72 women in whom breast biopsy reports described a solitary papilloma. All patients with additional pathologic abnormalities were excluded from this study. Patients meeting the pathologic criteria and for whom mammograms, galactograms, or both were available and had been obtained within 6 months before biopsy were included. Twenty-four women met these criteria and form the basis of this study. Presenting clinical signs and symptoms were reviewed. Abnormal mammographic/galactographic findings were correlated with pathologic features. RESULTS: Nipple discharge was present in 21 (88%) of 24 patients, two (8%) of 24 patients had abnormal findings on screening mammography, and one patient had a palpable mass that was visible on mammograms. Eight (42%) of 19 mammograms had abnormal findings, including dilated duct(s) in five cases (26%), nodules in two cases (11%), and microcalcifications in one case (5%). All technically adequate galactograms (13/15) had abnormal findings, with 12 (92%) of 13 showing an intraluminal filling defect. The other technically adequate galactogram (8%) showed only a solitary obstructed duct. Ductal dilatation was greatest at or central to the papilloma on 12 (92%) of 13 galactograms. Imaging features correlated well with the histologic findings. CONCLUSION: Patients with solitary papillomas most commonly have nipple discharge, normal mammographic findings, and a galactographic filling defect. Galactography is useful for localizing papillomas.

Prostate cancer: correlation of MR images with tissue optical density at pathologic examination.

To explain the variability in detection of prostate cancer with magnetic resonance (MR) imaging, the authors correlated preoperative MR findings in 28 patients with tissue optical density (TOD) measurements on whole-mount pathologic slides prepared from radical prostatectomy specimens. TOD was used as an indicator of the degree of tissue compactness or openness. TOD measurements from proved cancers and from pathologic regions corresponding to MR lesions (areas of low signal intensity seen at T2-weighted MR imaging) were compared with TOD measurements from adjacent, nonmalignant tissue. TOD measurements corresponding to MR lesions were higher than noncancerous tissue measurements in all cases (P less than .005). Although most of these lesions represented cancers (21 of 30), nine of 30 represented benign tissue that was composed mainly of densely packed fibromuscular stroma (30% false-positive results). Thus, signal intensity appeared to be related to TOD rather than to a specific histologic tissue type, and the finding of a peripheral zone lesion with low signal intensity did not necessarily indicate the presence of a cancer.

Spinal cord schistosomiasis: a pediatric case mimicking intrinsic cord neoplasm.

We present the clinical, myelographic, MRI, and histologic data on a 7-year-old girl with confirmed Schistosoma mansoni infection of the spinal cord. MRI of the granulomatous spinal lesion revealed extensive enlargement of the cord in the T11-12 area, with some intramedullary swelling extending to T-5 through T-7. The clinical manifestations of spinal schistosomiasis can be diverse, and there should be a high index of suspicion for all patients from endemic areas.

Carcinoma of the prostate: MR images obtained with body coils do not accurately reflect tumor volume.

MR imaging with a body coil is unreliable in directly demonstrating tumor spread through the prostatic capsule. However, the likelihood of extracapsular spread of prostatic cancer rises with increasing tumor volume. The aim of our study was to assess the accuracy of MR with a body coil in diagnosing capsular penetration indirectly via an estimation of prostatic tumor volumes. Twenty-six patients with proved prostatic cancer that was clinically confined to the gland underwent MR imaging before radical prostatectomy and whole-mount pathologic sectioning of the specimen. Twenty of 31 lesions prospectively outlined on the MR images corresponded to cancers outlined on the pathology slides, and tumor volumes were calculated by using a voxel summation technique. On MR, tumor volume was underestimated in 11 of 20 cases and overestimated in nine of 20 cases. Only two of 20 size estimates based on MR findings were within 10% of actual tumor volume. Overlap in MR tumor volumes was significant between lesions with and without capsular penetration at microscopy. Factors contributing to inaccuracies in measurements of tumor volume on MR images included the variable histologic make-up of the tumors. Our results show that, although knowledge of the size of a prostatic lesion is important in predicting the behavior of the tumor, MR imaging with a body coil is not reliable for accurate estimation of tumor volume.