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M Schnall

Publications and source records attributed to M Schnall.

At least 19 recordsLinked to original sources
PubMed2001

MR imaging of the breast in patients with invasive lobular carcinoma.

OBJECTIVE: Our objective was to assess the usefulness of MR imaging in patients diagnosed with invasive lobular carcinoma of the breast. MATERIALS AND METHODS: Between July 1993 and September 1999, 32 women (33 cases) diagnosed with pure invasive lobular carcinoma of the breast underwent contrast-enhanced MR imaging examination. One woman was excluded because of lack of follow-up. Correlation was made between the mammographic and sonographic findings, the MR imaging findings, and the final pathology results for the remaining 32 cases. RESULTS: In 18 women who did not undergo excisional biopsy before the MR imaging, MR imaging showed more extensive tumor burden or the detection of the primary lesion that was occult on conventional imaging in seven (38.9%) of 18 women. In nine (50%) of 18 women, MR imaging performed equally as well as mammography and sonography. In one case (5.6%), MR imaging and mammography underestimated disease extent. In another patient (5.6%), MR imaging overestimated tumor burden, although mammography failed to show the cancer. In 14 patients who had excisional biopsy before the MR imaging, residual tumor was shown in eight women (57.1%) with extensive tumor or additional separate foci in five of the eight patients. In two cases (14.3%) that were interpreted as equivocal, residual tumor was shown in both cases on reexcision. In three cases (21.4%), the MR imaging was interpreted as negative, but microscopic tumor was shown around seroma on reexcision. False-positive enhancement was seen in one case (7.1%). CONCLUSION: MR imaging showed more extensive tumor than conventional imaging and affected the clinical management in 16 (50%) of 32 patients with invasive lobular carcinoma.

Adult↗
PubMed2000

Concurrent MRI and diffuse optical tomography of breast after indocyanine green enhancement.

We present quantitative optical images of human breast in vivo. The images were obtained by using near-infrared diffuse optical tomography (DOT) after the administration of indocyanine green (ICG) for contrast enhancement. The optical examination was performed concurrently with a magnetic resonance imaging (MRI) exam on patients scheduled for excisional biopsy or surgery so that accurate image coregistration and histopathological information of the suspicious lesions was available. The ICG-enhanced optical images coregistered accurately with Gadolinium-enhanced magnetic resonance images validating the ability of DOT to image breast tissue. In contrast to simple transillumination, we found that DOT provides for localization and quantification of exogenous tissue chromophore concentrations. Additionally our use of ICG, an albumin bound absorbing dye in plasma, demonstrates the potential to differentiate disease based on the quantified enhancement of suspicious lesions.

Aged↗
PubMed2000

Endorectal magnetic resonance imaging as a predictor of biochemical outcome after radical prostatectomy in men with clinically localized prostate cancer.

PURPOSE: Endorectal magnetic resonance imaging (MRI) of the prostate is sometimes performed before radical prostatectomy but to our knowledge its role for predicting outcome after radical prostatectomy is not yet established. We evaluated the clinical usefulness of endorectal MRI for predicting time to prostate specific antigen (PSA) failure after radical prostatectomy in 1,025 consecutive men with clinically localized or PSA detected prostate cancer. Our analysis controlled for PSA level, biopsy Gleason score, clinical T stage and percent of positive biopsies. MATERIALS AND METHODS: Using Cox regression analysis we prospectively assessed time to PSA failure to determine the role of endorectal MRI in predicting PSA outcome after radical prostatectomy at our institution, where an expert prostate magnetic resonance radiologist is available. The main outcome measure was actuarial freedom from PSA failure. RESULTS: Endorectal MRI did not add clinically meaningful information in 834 of our 1,025 cases (81%) after accounting for the prognostic value of PSA, biopsy Gleason score, clinical T stage and percent of positive biopsies. However, this modality provided a clinically and statistically relevant stratification of 5-year PSA outcome in the remaining 191 patients at intermediate risk based on established prognostic factors. Specifically when endorectal MRI was interpreted as indicating extracapsular versus organ confined disease the relative risk of PSA failure was 3.6 (95% confidence interval 2.0 to 6.3), and 5-year actuarial freedom from PSA failure was 33% versus 72% (p <0.0001). CONCLUSIONS: Despite expert radiological interpretation endorectal MRI had potential clinical value in less than 20% of the cases in our study after accounting for established prognostic factors. While further study of the value of this modality for predicting clinical outcome after radical prostatectomy should be performed in this select cohort, routine use of endorectal MRI cannot be justified based on these data.

Actuarial Analysis↗
PubMed1998

Endorectal coil magnetic resonance imaging identifies locally advanced prostate cancer in select patients with clinically localized disease.

OBJECTIVES: Endorectal coil magnetic resonance imaging (erMRI) has been reported to improve the prediction of pathologic Stage T3 disease in patients with clinical Stage T1,2 disease, prostate-specific antigen (PSA) of 10 to 20 ng/mL, biopsy Gleason score of 7 or less, and at least 50% of the biopsy specimens positive from a sextant sampling. This study examines the performance characteristics of the erMRI to predict established extracapsular extension (ECE), seminal vesicle invasion (SVI), and PSA failure-free survival (bNED) in this subgroup. METHODS: The sensitivity, specificity, positive and negative predictive value, and accuracy of the erMRI to predict established ECE and SVI were calculated in the proposed subgroup. PSA failure-free survival stratified by the erMRI-defined stage was estimated by using the method of Kaplan and Meier. RESULTS: The sensitivity, specificity, positive and negative predictive value, and accuracy to predict established ECE and SVI in clinical Stage T1,2 patients was 65%, 100%, 100%, 79%, and 84%, respectively. No patient would have been excluded from surgery on the basis of a false-positive study. Moreover, the percent of patients with pathologic organ-confined disease would have increased from 32% to 61%, and the 3-year bNED rate would have increased from 12% to 45% (P = 0.07) if only patients with erMRI Stage T2 disease were selected for surgery. CONCLUSIONS: The erMRI may significantly improve the identification of established ECE and SVI in select patients with prostate cancer preoperatively. Further study of the erMRI in these select patients is warranted and ongoing.

Disease-Free Survival↗
PubMed1997

Combined modality staging of prostate carcinoma and its utility in predicting pathologic stage and postoperative prostate specific antigen failure.

OBJECTIVES: This study was performed to predict the factors that can optimize preoperative staging for clinically localized prostate cancer patients. METHODS: Logistic and Cox regression multivariable analyses were performed on 480 surgically-managed prostate cancer patients to evaluate the ability of clinical stage, prostate specific antigen (PSA), biopsy Gleason sum, percent positive biopsies, and endorectal coil magnetic resonance imaging (erMRI) results to predict for pathologic established extracapsular extension (ECE), seminal vesicle invasion (SVI), and time to postoperative PSA failure. RESULTS: The characteristics of clinically organ-confined prostate cancer patients at high risk (> 67%) for postoperative PSA failure within 3 years include: (A) PSA > 20 ng/mL; (B) Biopsy Gleason sum > or = 8; or (C) erMRI positive for extraprostatic disease and intermediate risk disease. For patients at intermediate risk (ie, either a PSA < 4 and biopsy Gleason sum of 7; PSA > 4 to 10 ng/mL and biopsy Gleason sum 5 to 7; or a PSA > 10 to 20 ng/mL and biopsy Gleason sum 2 to 7), despite 100% positive biopsies, 50% of patients had pathologic organ-confined disease. However, in the subset of intermediate-risk patients with a positive erMRI for either ECE or SVI and at least 50% positive biopsies, all had extraprostatic disease and failed biochemically by 47 months postoperatively. Intermediate-risk patients with < 50% positive biopsies had pathologic organ-confined disease in at least 77% of the cases. CONCLUSIONS: Combined modality staging using the PSA, biopsy Gleason sum, percent positive biopsies, and endorectal coil MRI findings in select patients can predict pathologic stage and postoperative PSA failure. Therefore, this combined modality staging may optimize patient selection for phase 3 trials examining the role of neoadjuvant androgen ablative therapy for patients with clinically localized disease.

Genital Neoplasms, Male↗
PubMed1996

An analysis of the time course of postoperative prostate-specific antigen failure in patients with positive surgical margins: implications on the use of adjuvant therapy.

OBJECTIVES: The role of adjuvant therapy in the postprostatectomy setting for positive margin patients is an unresolved issue. The purpose of this study is to provide the rationale for patient selection in Phase III trials that test the impact of adjuvant therapy on survival in positive margin prostate cancer patients. METHODS: Early (12 months or less) and delayed (more than 12 months) postoperative prostate-specific antigen (PSA) failure have been correlated with distant and local failure, respectively, as the site of first failure. In this study, a Cox regression multivariate analysis was used to determine the significant independent clinical and pathologic predictors of early and delayed postoperative PSA failure in 143 margin-positive prostate cancer patients. RESULTS: Margin-positive patients with positive pelvic lymph nodes, seminal vesicle invasion, or prostatectomy Gleason sum 8 or higher were excluded. For the remaining patients, a prostatectomy Gleason sum of 7, preoperative PSA more than 20 ng/mL, and an endorectal coil magnetic resonance imaging (erMRI) scan showing extensive disease were significant independent predictors of early postoperative PSA failure. Conversely, a prostatectomy Gleason sum of 6 or less, preoperative PSA 20 ng/mL or less, and an erMRI showing limited disease predicted delayed PSA failure. CONCLUSIONS: Preliminary data suggest that the pattern of first failure can be predicted by the time course of rise in the postoperative PSA. The preliminary results of this study suggest that patient selection for clinical trials examining the efficacy of postoperative adjuvant therapy in the positive margin patient may be determined on the basis of the clinical and pathologic characteristics that predict early versus delayed postoperative PSA failure.

Clinical Trials, Phase III as Topic↗
PubMed1996

Critical analysis of the ability of the endorectal coil magnetic resonance imaging scan to predict pathologic stage, margin status, and postoperative prostate-specific antigen failure in patients with clinically organ-confined prostate cancer.

PURPOSE: To determine whether there is a role for endorectal coil magnetic resonance imaging (erMRI) in the prediction of pathologic stage, margin status, and/or postoperative prostate-specific antigen (PSA) failure in patients with clinically organ-confined prostate cancer. PATIENTS AND METHODS: Using erMRI, the radiologic-pathologic correlation of extracapsular extension (ECE) and seminal vesicle invasion (SVI) was evaluated in 445 surgically managed patients. Logistic regression multivariable analysis was applied to the clinical stage, PSA, biopsy Gleason grade, and erMRI findings to assess the outcomes of ECE, SVI, positive surgical margins (PSM), and postoperative PSA failure. RESULTS: The accuracy of erMRI to predict for ECE and SVI numerically decreased with both increasing PSA and biopsy Gleason score because of the increasing false-negative scans in cases of microscopic transcapsular or seminal vesicle disease. Of patients who could not be categorized into low or high risk for postoperative PSA failure on the basis of clinical stage, preoperative PSA, and biopsy Gleason score, a negative or positive erMRI for ECE or SVI stratified these patients into groups with a 78% versus 21% (P < .0001) 3-year rate of actuarial freedom from PSA failure. In this subgroup, the overall accuracy of the erMRI was 70% +/- 6% and 94% +/- 2% for ECE and SVI, respectively. The most significant predictor on multivariable analysis of PSM was the erMRI finding of ECE (P = .0001). CONCLUSION: This initial report suggests that a preoperative erMRI can identify clinically organ-confined prostate cancer patients at high risk for having ECE, SVI, and PSM that otherwise would be missed on the basis of the clinical stage, preoperative PSA, and biopsy Gleason score. Confirmatory studies are needed.

Adenocarcinoma↗
PubMed1995

The impact of the inclusion of endorectal coil magnetic resonance imaging in a multivariate analysis to predict clinically unsuspected extraprostatic cancer.

BACKGROUND: The introduction of the endorectal coil magnetic resonance imaging (MRI) technique has improved the accuracy of preoperative staging for prostate cancer. This study quantifies the improvement in the ability to identify clinically unsuspected extraprostatic disease with the use of the endorectal coil MRI. METHODS: A retrospective review of the pathologic findings of 347 patients with prostate cancer treated with a radical retropubic prostatectomy was performed. The preoperative clinical indicators including prostate specific antigen (PSA), clinical stage, Gleason score, and endorectal coil MRI data were employed in a multivariate analysis to identify patients who were at high risk for seminal vesicle invasion (SVI) or extracapsular extension (ECE). The sensitivity, specificity, and positive and negative predictive values for predicting SVI and ECE were calculated using the significant clinical indicators found on the multivariate analysis. RESULTS: The clinical factors identified on multivariate analysis as significant predictors of SVI include the endorectal coil MRI data (P < 0.0001), PSA (P = 0.0096), and the Gleason score (P = 0.012). Endorectal coil MRI data (P < 0.0001), PSA (P = .0001), and Gleason score (P < .0001) were significant predictors of ECE. In the patient subgroup with PSA (> 10-20 ng/ml) and Gleason score of 5 to 7, the addition of the endorectal coil MRI data enabled an additional 71 and 27% of patients with SVI and ECE, respectively, to be correctly identified. These patients would have been missed based on the prediction obtained from the PSA and Gleason score alone. CONCLUSIONS: The use of the endorectal coil magnetic resonance imaging data, in addition to prostate specific antigen and Gleason score, provides a more accurate prediction of the pathologic outcome of seminal vesicle invasion and extracapsular extension than the PSA and Gleason score alone for the patient subgroup with a PSA of greater than 10 to 20 ng/ml and Gleason score of 5 to 7.

Adenocarcinoma↗
PubMed1995

Improved treatment planning for the Syed-Neblett template using endorectal-coil magnetic resonance and intraoperative (laparotomy/laparoscopy) guidance: a new integrated technique for hysterectomized women with vaginal tumors.

The Syed template (Alpha-Omega Services, Bellflower, CA) represents an advance in interstitial gynecologic brachytherapy; however, its appeal is diminished by inaccuracies in target definition secondary to suboptimal imaging of gynecologic tumors and the risk of viscus perforation during a "blind" procedure. Magnetic resonance (MR) scanning with an endorectal coil and computed tomography were studied as a possible tool to improve target definition and maximize treatment planning with Syed templates. Abdominopelvic contents could be visualized directly through a laparotomy incision or indirectly with a laparoscopic video display to allow further target definition and minimize complications associated with blind procedures after hysterectomy. The synthesis of these techniques with Syed template applications was attempted to potentiate the utility of this brachytherapy system. Five patients with apical vaginal tumors which arose after previous hysterectomies (two endometrial cancer recurrences, one recurrent uterine sarcoma, two primary vaginal cancers) were referred for radiotherapy. In three cases, external beam pelvic radiotherapy (median dose, 45 Gy; range, 45-50.4 Gy) was delivered initially. In all cases, the Syed applicator was used for the brachytherapy component of the treatment. In two cases, high-resolution MR images (400 x 400 microns) of the vaginal apex were obtained after insertion of an endorectal surface coil. The images defined the relationships between the template, target volume, bladder, rectum, and intestine. The other three cases were planned with computerized tomography (CT). In all cases, intraoperative examination of the abdominopelvic contents was provided when laparotomy and/or laparoscopy was performed by the surgical team. The median brachytherapy dose prescribed to the isodose envelope covering the target volume was 40 Gy (range, 31-50 Gy). In all cases, the target volumes could be encompassed by the 60 cGy/hr isodose line. Tumor volume estimation was better with MR than CT. Procedure time was shorter with laparoscopy than with laparotomy. In two cases, bowel displacement was performed (one tissue expander, one omental sling) to prevent viscus perforation by interstitial needles. Four of five patients responded completely to the treatment. In three cases, local control was maintained at a median follow-up of 11 months. In conclusion, endorectal coil MRI may be advantageous to CT of the pelvis in that it allows preplanning to be achieved with greater precision and with less planning time. Major intraoperative complications (i.e., perforation of hollow viscus organs) can be avoided when the course of interstitial catheters is visualized from above by the surgical team.(ABSTRACT TRUNCATED AT 400 WORDS)

Brachytherapy↗
PubMed1995

A multivariate analysis of clinical and pathological factors that predict for prostate specific antigen failure after radical prostatectomy for prostate cancer.

A Cox regression multivariate analysis was done to determine the clinical and pathological indicators that predict for prostate specific antigen (PSA) failure in 347 patients who underwent radical prostatectomy for clinically localized prostate cancer between 1989 and 1993. In the patient subgroups (PSA less than 20 ng./ml. and biopsy Gleason sum 5 to 7 or PSA more than 10 to 20 ng./ml. and biopsy Gleason sum 2 to 4) not classifiable into those at high and low risk for postoperative PSA failure using PSA and biopsy Gleason sum, the status of the seminal vesicles and prostatic capsule on endo-rectal coil magnetic resonance imaging (MRI) allowed for this categorization. Specifically, 2-year actuarial PSA failure rates were 84% versus 23% in patients with and without seminal vesicle invasion, respectively, on MRI (p < 0.0001) and 58% versus 21% in those with and without extracapsular extension, respectively (p = 0.0001). In patients with extracapsular extension but without pathological involvement of the seminal vesicle(s) or poorly differentiated tumors (pathological Gleason sum 8 to 10), the 2-year actuarial PSA failure rates were 50% (margin positive), 28% (margin negative with established extracapsular disease) and 9% (margin negative with focal microscopic extracapsular disease). Therefore, endo-rectal coil MRI showing seminal vesicle invasion or extracapsular extension when the PSA level is less than 20 ng./ml. and the biopsy Gleason sum is 5 to 7 or the PSA level is more than 10 but less than 20 ng./ml. and the biopsy Gleason sum is 2 to 4 predicted for PSA failure. In patients with extracapsular extension who had pathological Gleason sum less than 8 disease with uninvolved seminal vesicles, the margin status and extent of extracapsular disease predicted for PSA failure.

Actuarial Analysis↗
PubMed1994

A multivariable analysis of clinical factors predicting for pathological features associated with local failure after radical prostatectomy for prostate cancer.

PURPOSE: A multivariate analysis is used to determine the predictive value of pretreatment clinical indicators on pathologic features associated with local failure after radical prostatectomy in patients with prostate cancer. METHODS AND MATERIALS: A retrospective review of the pathologic findings of 235 patients with adenocarcinoma of the prostate treated between 1990 and 1993 with a radical retropubic prostatectomy was performed. The preoperative clinical data including the serum prostate specific antigen, clinical stage, Gleason sum, and endorectal magnetic resonance scan findings are used to identify patients prior to definitive treatment who would be at high risk for having pathologic features associated with local failure at radical prostatectomy. Outcome prediction curves are constructed from a logistic regression multivariate analysis displaying the probability of pathologic involvement of the seminal vesicle, extracapsular disease, or positive surgical margins as a function of the preoperative prostate specific antigen and Gleason sum for the cases when the endorectal magnetic resonance scan is positive, negative, or not included in the multivariate analysis. RESULTS: Factors identified on multivariate analysis as significant predictors of seminal vesicle invasion include endorectal magnetic resonance scan findings (p < 0.0001), and preoperative prostate specific antigen (p = 0.017). Endorectal magnetic resonance scan findings (p = 0.0016), preoperative prostate specific antigen (p = 0.0002), and Gleason sum (p < 0.0001) were significant predictors of extracapsular extension and preoperative prostate specific antigen (p < 0.0001) and Gleason sum (p = 0.03) were significant predictors of disease extending to the margins of resection. Clinical stage was not a significant predictor (p > 0.05) of pathologic features associated with local failure on multivariate analysis. As a single modality, endorectal surface coil magnetic resonance imaging was accurate 93%, 69%, and 72% of the time for predicting seminal vesicle invasion, transcapsular disease, and final pathologic stage, respectively. Failure to recognize microscopic penetration of the capsule found at the time of pathologic evaluation in a prostate gland with a grossly intact capsule accounts for the majority (70%) of the staging inaccuracies. CONCLUSIONS: The use of the endorectal surface coil magnetic resonance scan findings in conjunction with both the serum prostate specific antigen and Gleason sum improves the clinical accuracy of predicting those patients at high risk for clinically unsuspected extraprostatic disease. In particular, for the subgroup of patients with moderately elevated prostate specific antigen (> 10-20 ng/mL) and intermediate grade clinically organ confined prostate cancer [Gleason sum: 5-7] where the specificity of these tests to predict for occult extraprostatic disease is suboptimal, the additional information obtained from the endorectal coil magnetic resonance scan allows the physician to definitively subgroup these patients into low and high risk for seminal vesicle invasion or transcapsular disease.

Adenocarcinoma↗
PubMed1994

Hepatic metastases and cavernous hemangiomas: distinction with standard- and triple-dose gadoteridol-enhanced MR imaging.

PURPOSE: To determine if hepatic metastases can be distinguished from cavernous hemangiomas by pattern analysis of magnetic resonance (MR) images obtained prior to and following administration of gadoteridol at standard (0.1 mmol/kg) and triple (0.3 mmol/kg) doses. MATERIALS AND METHODS: Ninety-five patients with proved hepatic metastases (n = 71) or cavernous hemangiomas (n = 24) underwent MR imaging at 16 different institutions. T2-weighted spin-echo and T1-weighted images were obtained before and after gadoteridol administration. Two independent blinded reviewers rated individual features of benignancy versus malignancy on a five-point confidence scale. RESULTS: The most useful diagnostic features, with 100% specificity, were nodular enhancement for hemangiomas and rim enhancement for metastases. Confident (definitely benign or definitely malignant) diagnoses were rendered in 80 of 95 cases (84%), with an accuracy of a confident diagnosis of 96%. CONCLUSION: The pattern of enhancement on T1-weighted images is highly accurate for distinction between hemangiomas and metastases in images obtained with both doses.

Contrast Media↗
PubMed1991

Rectal carcinoma: staging at MR imaging with endorectal surface coil. Work in progress.

To increase the accuracy of local staging of rectal carcinomas at magnetic resonance (MR) imaging, the authors placed on endorectal coil mounted on a balloon in a position adjacent to the lesion. Use of such a local coil resulted in increased signal-to-noise ratio compared with use of a body coil; higher-resolution images were obtained because the field of view was decreased. The depth of wall invasion by rectal carcinoma was correctly staged with endorectal MR imaging in 11 of 12 patients. In the detection of perirectal adenopathy, use of MR enabled correct identification of positive perirectal nodes in four of seven patients (57%). There were no false-positive diagnoses of perirectal adenopathy at MR. Endorectal MR imaging is an evolving and promising technique for the local staging of rectal carcinomas, but further studies are needed to demonstrate its efficacy.

Female↗
PubMed1988

Metabolic myopathy in canine muscle-type phosphofructokinase deficiency.

In vivo 31phosphorus nuclear magnetic resonance spectroscopy (P-NMR) of the anterior tibialis muscle was used to investigate the metabolic myopathy of inherited muscle-type phosphofructokinase (PFK) deficiency in four (homozygous) dogs who had mild exercise intolerance, rare muscle cramps, increased serum creatine kinase activity, but no myoglobinuria. During isometric muscle work induced by indirect electrical stimulation, and subsequent recovery, changes in the ratio of phosphocreatine (PCr) and inorganic phosphates (Pi) were comparable in muscle of PFK-deficient and normal dogs and indicated a large capacity for arobic oxidative phosphorylation in canine muscle. The progressive accumulation of sugar phosphates (PME) during graded exercise clearly demonstrated the glycolytic block in PFK-deficient dogs. During a muscle contracture, induced by acute muscle stimulation, PFK-deficient muscle became completely depleted of PCr and ATP, accumulated large amounts of PME, and recovered very slowly. We conclude that PFK-deficient dogs have a metabolic myopathy that demonstrated some but not all the features recognized in the human disorder.

Animals↗