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Hedvig Hricak

Publications and source records attributed to Hedvig Hricak.

9 recordsLinked to original sources

Transition zone prostate cancer: metabolic characteristics at 1H MR spectroscopic imaging--initial results.

PURPOSE: To determine whether cancers of the prostate transition zone (TZ) possess a unique metabolic pattern by which they may be identified at proton magnetic resonance (MR) spectroscopic imaging. MATERIALS AND METHODS: Findings in 40 patients who underwent combined endorectal MR imaging and hydrogen 1 MR spectroscopic imaging before radical prostatectomy and who had TZ tumor identified subsequently at step-section pathologic analysis were retrospectively reviewed. Within this population, a subset of 16 patients whose TZ tumor had a largest diameter of 1 cm or greater and was included in the MR spectroscopic imaging excitation volume was identified. In these 16 patients, the ratios of choline-containing compounds (Cho) and creatine/phosphocreatine (Cr) to citrate (Cit) (ie, [Cho + Cr]/Cit), Cho/Cr, and Cho/Cit were compared in tumor and control tissues. The presence of only Cho and the absence of all metabolites were also assessed. RESULTS: The mean values of (Cho + Cr)/Cit, Cho/Cr, and Cho/Cit were different between TZ cancer and control tissues (P =.001, P =.003, and P =.001, respectively; Wilcoxon signed rank test). Nine (56%) of 16 patients had at least one tumor voxel in which Cho comprised the only detectable peak, while no control voxels showed only Cho (P =.008, McNemar test). The percentage of voxels in which no metabolites were detected did not differ between tumor and control tissues (P =.134, McNemar test). CONCLUSION: TZ cancer has a metabolic profile that is different from that of benign TZ tissue; however, the broad range of metabolite ratios observed in TZ cancer precludes the use of a single ratio to differentiate TZ cancer from benign TZ tissue.

Choline↗

The use of MRI in the diagnosis and management of a bulky cervical carcinoma.

BACKGROUND: In the treatment of gynecologic cancer, surgical planning depends on the site and extent of disease. The evaluation of the origin of a large pelvic mass with combined pelvic examination and ultrasound is often adequate. However, the following case report illustrates the utility of magnetic resonance imaging (MRI) when sonographic findings are indeterminate and the origin of a pelvic mass is unclear. CASE: A 73-year-old woman presented for her first gynecologic exam in over 40 years. On speculum examination the cervix was not visible. A large, mobile pelvic mass was palpated during physical examination. Pelvic ultrasound revealed a large, cystic pelvic mass thought to be ovarian in origin. Surgery for presumed ovarian carcinoma was planned. Because a vaginal Pap smear revealed squamous-cell carcinoma, MRI was performed for further evaluation. MRI demonstrated a blood distended uterus with a large cervical tumor obstructing the endocervical os. After cervical dilatation under sonographic guidance, evacuation of the hematometrium was performed. Multiple biopsies of the cervix confirmed the diagnosis of a bulky Stage IIA squamous-cell carcinoma of the cervix. The patient was subsequently treated with concomitant chemotherapy and radiation therapy. Follow-up MRI demonstrated an excellent treatment response. Modified radical hysterectomy was performed demonstrating very small residual tumor. CONCLUSIONS: Magnetic resonance imaging, through multiplanar capabilities and high-contrast resolution, is a valuable tool that can assist the clinician in the evaluation, diagnosis, and management of challenging gynecologic malignancies.

Aged↗

Urinary continence after radical retropubic prostatectomy: relationship with membranous urethral length on preoperative endorectal magnetic resonance imaging.

PURPOSE: We determined whether membranous urethral length on preoperative magnetic resonance imaging (MRI) is predictive of urinary continence after radical retropubic prostatectomy. MATERIALS AND METHODS: Membranous urethral length was measured on preoperative endorectal MRI in 211 consecutive patients with newly diagnosed prostate cancer before radical retropubic prostatectomy performed by a single surgeon. Neurovascular bundle resection was done in 60 cases. After surgery the time to stable postoperative continence was recorded in 180 cases and the level of stable continence was graded on a 5-point scale of 1-complete continence to 5-complete incontinence. RESULTS: After controlling for age and surgical technique multivariate analysis showed that membranous urethral length was related to time to stable postoperative continence (p = 0.02), such that a longer membranous urethra was associated with a shorter time to stable continence. For example, 1 year after surgery 120 of the 134 patients (89%) with a preoperative membranous urethral length of greater than 12 mm. were completely continent compared with 35 of the 46 (77%) with a preoperative length of 12 mm. or less. CONCLUSIONS: On endorectal MRI before radical prostatectomy a longer membranous urethra is associated with significantly more rapid return of urinary continence after surgery.

Adult↗

What do we expect from imaging?

The objectives of imaging in gynecologic cancer include tumor detection, tumor diagnosis, staging, and follow-up. In addition, both monitoring response to treatment and differentiating tumor recurrence from post-treatment changes are important indications for imaging. In 2001 it was estimated that there would be 38,300 cases of endometrial cancer, 23,400 cases of ovarian cancer, and 12,900 cases of cervical cancer. This article reviews what information is required by the practicing gynecologist or gynecologic oncologist prior to surgery and briefly summarizes state-of-the-art imaging in answering clinically pertinent questions.

Diagnostic Imaging↗

Blood loss during radical retropubic prostatectomy: relationship to morphologic features on preoperative endorectal magnetic resonance imaging.

OBJECTIVES: To determine whether morphologic features at preoperative magnetic resonance imaging (MRI) are related to intraoperative blood loss during radical retropubic prostatectomy. METHODS: Endorectal MRI was performed in 143 patients with newly diagnosed prostate cancer before radical retropubic prostatectomy. Two independent readers rated the prominence of the periprostatic veins (on the basis of number and size) at four anatomic sites on a 3-point scale. Other features analyzed were prostate volume and interspinous diameter. RESULTS: A prominence of the anterior and posterior apical periprostatic veins was positively associated with blood loss (correlation coefficient = 0.22 and 0.17 and P <0.01 and <0.05, respectively). Blood loss was not related to prostate volume (correlation coefficient = 0.02, P = 0.8) or interspinous diameter (correlation coefficient = 0.01, P = 0.9). The site-specific scores of both readers demonstrated positive agreement, with Pearson's correlation coefficients of 0.51 to 0.65 (P <0.01). CONCLUSIONS: A marked prominence of the apical periprostatic veins on preoperative MRI is associated with greater intraoperative blood loss during radical retropubic prostatectomy. Other morphologic factors appear unrelated to the amount of intraoperative blood loss.

Adult↗

Prostate cancer tumor volume: measurement with endorectal MR and MR spectroscopic imaging.

PURPOSE: To determine accuracy of magnetic resonance (MR) and three-dimensional (3D) MR spectroscopic imaging in prostate cancer tumor volume measurement. MATERIALS AND METHODS: Endorectal MR and 3D MR spectroscopic imaging were performed in 37 patients before radical prostatectomy. Two independent readers recorded peripheral zone tumor nodule location and volume. Results were analyzed with step-section histopathologic tumor localization and volume measurement as the standard. Accuracy of tumor volume measurement was assessed with the Pearson correlation coefficient. P values were calculated with a random effects model. Bland-Altman regression analysis was used to evaluate systematic bias between tumor volumes measured with MR imaging and true tumor volumes. Analyses were performed for all nodules and nodules greater than 0.50 cm(3). RESULTS: Mean volume of peripheral zone tumor nodules (n = 51) was 0.79 cm(3) (range, 0.02-3.70 cm(3)). Two readers detected 20 (65%) and 23 (74%) of 31 peripheral zone tumor nodules greater than 0.50 cm(3). For these nodules, measurements of tumor volume with MR imaging, 3D MR spectroscopic imaging, and a combination of both were all positively correlated with histopathologic volume (Pearson correlation coefficients of 0.49, 0.59, and 0.55, respectively); only measurements with 3D MR spectroscopic imaging and a combination of MR and 3D MR spectroscopic imaging demonstrated statistical significance (P <.05). Tumor volume estimation with all three methods was more accurate for higher tumor volumes. CONCLUSION: Addition of 3D MR spectroscopic imaging to MR imaging increases overall accuracy of prostate cancer tumor volume measurement, although measurement variability limits consistent quantitative tumor volume estimation, particularly for small tumors.

Adult↗

Peritoneal metastases: detection with spiral CT in patients with ovarian cancer.

PURPOSE: To determine the accuracy of spiral computed tomography (CT) in the depiction of peritoneal metastases by using surgical findings in patients with ovarian cancer as the standard of reference. MATERIALS AND METHODS: Three independent readers reviewed the preoperative CT scans obtained in 64 patients who underwent primary surgery for ovarian cancer. Readers rated the likelihood of peritoneal metastases on a five-point scale and recorded the presence or absence of ascites, parietal peritoneal thickening or enhancement, and small-bowel wall thickening or distortion. Peritoneal metastases were identified as nodular, plaquelike, or infiltrative soft-tissue lesions in the peritoneal fat or on the peritoneal surface. Area under the receiver operating characteristic curve was calculated for each reader. Interreader agreement was evaluated with the kappa statistic. Descriptive statistical data were determined with dichotomized ratings (1-3 = absent; 4-5 = present). RESULTS: Areas under the receiver operating characteristic curves for the three readers were 0.95, 0.93, and 0.89. Paired kappa values ranged from 0.75 to 0.91. Reader sensitivity for metastases 1 cm or smaller in maximum diameter (25%-50%) was significantly (P <.05) lower than overall sensitivity (85%-93%). Ascites, parietal peritoneal thickening or enhancement, and small-bowel wall thickening or distortion demonstrated positive predictive values of 72%-93%, with kappa values of 0.12-0.80. CONCLUSION: Spiral CT is accurate in the depiction of peritoneal metastases from ovarian cancer, although sensitivity is reduced in patients with tumor implants 1 cm or smaller. Ancillary signs of peritoneal malignancy are limited by low interobserver agreement.

Adult↗