The utility of magnetic resonance imaging and spectroscopy for predicting insignificant prostate cancer: an initial analysis.

OBJECTIVE: To design new models that combine clinical variables and biopsy data with magnetic resonance imaging (MRI) and MR spectroscopic imaging (MRSI) data, and assess their value in predicting the probability of insignificant prostate cancer. PATIENTS AND METHODS: In all, 220 patients (cT stage T1c or T2a, prostate-specific antigen level <20 ng/mL, biopsy Gleason score 6) had MRI/MRSI before surgery and met the inclusion criteria for the study. The probability of insignificant cancer was recorded retrospectively and separately for MRI and combined MRI/MRSI on a 0-3 scale (0, definitely insignificant; - 3, definitely significant). Insignificant cancer was defined from surgical pathology as organ-confined cancer of

Prediction of seminal vesicle invasion in prostate cancer: incremental value of adding endorectal MR imaging to the Kattan nomogram.

PURPOSE: To retrospectively determine whether endorectal magnetic resonance (MR) imaging findings contribute incremental value to the Kattan nomogram for predicting seminal vesicle invasion (SVI) in patients with prostate cancer. MATERIALS AND METHODS: The institutional review board issued a waiver of authorization, which included a waiver of informed consent, for this HIPAA-compliant study. From October 2000 through January 2005, 573 patients (mean age, 58.3 years; age range, 36-86 years) underwent endorectal MR imaging before prostate cancer surgery. The endorectal MR imaging results had been prospectively interpreted by seven radiologists, and the likelihood of SVI was retrospectively scored on the basis of radiologists' written reports. MR imaging findings, individual clinical variables (serum prostate-specific antigen [PSA] level, Gleason grade, clinical stage, greatest percentage of cancer in all biopsy cores, percentage of positive cores in all biopsy cores, and perineural invasion), and the Kattan nomogram were evaluated with respect to SVI prediction; surgical pathologic analysis was used as the reference standard. Logistic regression and receiver operating characteristic (ROC) curve analyses were performed. RESULTS: At pathologic analysis, 28 (4.9%) of 573 patients had SVI. At univariate analysis, endorectal MR imaging results and all clinical variables except the percentage of positive biopsy cores were significantly associated with SVI (P<.02); endorectal MR imaging (0.76) had a larger area under the ROC curve (AUC) than any clinical variable (0.62-0.73). At multivariate analysis, endorectal MR imaging results, Gleason grade, PSA level, and the percentage of cancer in all biopsy cores were significantly associated with SVI (P

Combined endorectal and phased-array MRI in the prediction of pelvic lymph node metastasis in prostate cancer.

OBJECTIVE: The objectives of our study were to evaluate the accuracy of combined endorectal and phased-array MRI in detecting pelvic lymph node metastasis (LNM) in patients with prostate cancer and to determine whether radiologists' predictions of LNM improve with the incorporation of Partin nomogram or MRI findings (or both) regarding extracapsular extension or seminal vesicle invasion. SUBJECTS AND METHODS: Between May 1999 and September 2003, 411 consecutive patients with clinically localized prostate cancer underwent MRI before surgery. Serum prostate-specific antigen (PSA) level, Gleason grade, clinical stage, greatest percentage of cancer and percentage of positive cores in all biopsy cores, presence of perineural invasion on biopsy, and likelihood of LNM based on the Partin tables (2001 version) were recorded. MRI studies were interpreted prospectively, but the risks of LNM, extracapsular extension, and seminal vesicle invasion were scored retrospectively on the basis of the MRI reports. Surgical pathology constituted the standard of reference. The accuracy of LNM prediction was assessed using areas under receiver operating characteristic curves (AUCs) and univariate and multivariate logistic regression analyses. For multivariate models, the jackknife method was used for bias correction. A p value below 0.05 denoted statistical significance. RESULTS: At surgical pathology, LNM was present in 22 (5%) of 411 patients. MRI was an independent statistically significant predictor of LNM (p = 0.002), with positive and negative predictive values of 50% and 96.36%, respectively. On multivariate analysis, prediction of lymph node status using the model that included all MRI variables (extracapsular extension, seminal vesicle invasion, and LNM) along with the Partin nomogram results had a significantly greater AUC than the univariate model that included only MRI LNM findings (AUC = 0.892 vs 0.633, respectively; p < 0.01). CONCLUSION: Incorporation of the Partin nomogram results and MRI findings regarding both extracapsular extension and seminal vesicle invasion improves the MR prediction of LNM in patients with prostate cancer.

Prediction of organ-confined prostate cancer: incremental value of MR imaging and MR spectroscopic imaging to staging nomograms.

PURPOSE: To assess retrospectively the incremental value of endorectal coil magnetic resonance (MR) imaging and combined endorectal MR imaging-MR spectroscopic imaging to the staging nomograms for predicting organ-confined prostate cancer (OCPC). MATERIALS AND METHODS: The institutional review board approved this HIPAA-compliant study and issued a waiver of informed consent for review of the MR reports and clinical data. Between November 1, 1999, and November 1, 2004, 229 patients underwent endorectal MR imaging and 383 underwent combined endorectal MR imaging-MR spectroscopic imaging before radical prostatectomy. Mean patient age was 58 years (range, 32-74 years). MR studies were interpreted prospectively by 12 radiologists who were informed of patients' clinical data. On the basis of the MR reports, the risks of extracapsular extension, seminal vesicle invasion, and lymph node metastasis were scored retrospectively from 1 to 5; the highest score was subtracted from 6 to determine a score (from 1 to 5) for the likelihood of OCPC on MR studies. The staging nomograms were used to calculate the likelihood of OCPC on the basis of serum prostate-specific antigen level, Gleason grade at biopsy, and clinical stage. Histopathologic findings constituted the reference standard. Logistic regression was used to estimate the multivariable relations between OCPC and MR findings. The area under the receiver operator characteristic curve was calculated for each model. The jackknife method was used for bias correction. RESULTS: MR findings contributed significant incremental value (P

Comparison of endorectal magnetic resonance imaging, guided prostate biopsy and digital rectal examination in the preoperative anatomical localization of prostate cancer.

PURPOSE: We compared the accuracy of endorectal magnetic resonance imaging (erMRI), transrectal ultrasound (TRUS) guided biopsy and digital rectal examination (DRE) for detecting the location of cancer in the prostate gland and seminal vesicles. MATERIALS AND METHODS: This is a retrospective study of 106 consecutive patients with prostate cancer who were referred for erMRI before radical prostatectomy. Step-section pathological data and erMRI were available in 90 patients, DRE data were available on 86 and individually labeled sextant core biopsies were available in 45. T1 and T2-weighted erMRI was interpreted by a single reader, who scored the likelihood of tumor on a 5-point scale in each seminal vesicle and in 12 locations in the prostate gland. MR spectroscopy data were not used for erMRI interpretation. One pathologist reviewed whole mount serial sections of radical prostatectomy specimens. The area under ROC curves was used to evaluate accuracy. RESULTS: The area under ROC curves for tumor localization was higher for erMRI than for DRE at the prostatic apex (0.72 vs 0.66), mid gland (0.80 vs 0.69) and base (0.83 vs 0.69). It was likewise higher for erMRI than for TRUS biopsy in the mid gland (0.75 vs 0.68) and base (0.81 vs 0.61) but not in the apex (0.67 vs 0.70). On mixed model analysis erMRI significantly increased the accuracy of prostate cancer localization by DRE or TRUS biopsy (each p <0.0001). CONCLUSIONS: For prostate cancer localization erMRI contributes significant incremental value to DRE or TRUS biopsy findings (each p <0.0001).

Pattern of prostate-specific antigen (PSA) failure dictates the probability of a positive bone scan in patients with an increasing PSA after radical prostatectomy.

PURPOSE: Physicians often order periodic bone scans (BS) to check for metastases in patients with an increasing prostate-specific antigen (PSA; biochemical recurrence [BCR]) after radical prostatectomy (RP), but most scans are negative. We studied patient characteristics to build a predictive model for a positive scan. PATIENTS AND METHODS: From our prostate cancer database we identified all patients with detectable PSA after RP. We analyzed the following features at the time of each bone scan for association with a positive BS: preoperative PSA, time to BCR, pathologic findings of the RP, PSA before the BS (trigger PSA), PSA kinetics (PSA doubling time, PSA slope, and PSA velocity), and time from BCR to BS. The results were incorporated into a predictive model. RESULTS: There were 414 BS performed in 239 patients with BCR and no history of androgen deprivation therapy. Only 60 (14.5%) were positive for metastases. In univariate analysis, preoperative PSA (P = .04), seminal vesicle invasion (P = .02), PSA velocity (P < .001), and trigger PSA (P < .001) predicted a positive BS. In multivariate analysis, only PSA slope (odds ratio [OR], 2.71; P = .03), PSA velocity (OR, 0.93; P = .003), and trigger PSA (OR, 1.022; P < .001) predicted a positive BS. A nomogram for predicting the bone scan result was constructed with an overfit-corrected concordance index of 0.93. CONCLUSION: Trigger PSA, PSA velocity, and slope were associated with a positive BS. A highly discriminating nomogram can be used to select patients according to their risk for a positive scan. Omitting scans in low-risk patients could reduce substantially the number of scans ordered.

Correlation of proton MR spectroscopic imaging with gleason score based on step-section pathologic analysis after radical prostatectomy.

PURPOSE: To determine whether hydrogen 1 magnetic resonance (MR) spectroscopic imaging can be used to predict aggressiveness of prostate cancer. MATERIALS AND METHODS: All patients gave informed consent according to an institutionally approved research protocol. A total of 123 patients (median age, 58 years; age range, 40-74 years) who underwent endorectal MR imaging and MR spectroscopic imaging between January 2000 and December 2002 were included. MR imaging and spectroscopy were performed by using combined pelvic phased-array and endorectal probe. Water and lipids were suppressed, and phase-encoded data were acquired with 6.2-mm resolution. Voxels in the peripheral zone were considered suspicious for cancer if (Cho + Cr)/Cit was at least two standard deviations above the normal level, where Cho represents choline-containing compounds, Cr represents creatine and phosphocreatine, and Cit represents citrate. Correlation between metabolite ratio and four Gleason score groups identified at step-section pathologic evaluation (3 + 3, 3 + 4, 4 + 3, and > or =4 + 4) was assessed with generalized estimating equations. RESULTS: Data from 94 patients were included. Pathologic evaluation was used to identify 239 lesions. Overall sensitivity of MR spectroscopic imaging was 56% for tumor detection, increasing from 44% in lesions with Gleason score of 3 + 3 to 89% in lesions with Gleason score greater than or equal to 4 + 4. There was a trend toward increasing (Cho + Cr)/Cit with increasing Gleason score in lesions identified correctly with MR spectroscopic imaging. Tumor volume assessed with MR spectroscopic imaging increased with increasing Gleason score. CONCLUSION: MR spectroscopic imaging measurement of prostate tumor (Cho + Cr)/Cit and tumor volume correlate with pathologic Gleason score. There is overlap between MR spectroscopic imaging parameters at various Gleason score levels, which may reflect methodologic and physiologic variations. MR spectroscopic imaging has potential in noninvasive assessment of prostate cancer aggressiveness.

Bladder cancer as a prognostic factor for upper tract transitional cell carcinoma.

PURPOSE: Upper tract transitional cell carcinoma (UTTCC) is a relatively rare tumor. Overall 5-year disease specific survival is in the range of 16.5% to 95% depending on stage. In this study we evaluated predictors associated with disease recurrence and disease specific survival. MATERIALS AND METHODS: We report on 129 patients with a median age of 68 years who underwent nephroureterectomy for UTTCC between July 1989 and June 2002. A total of 67 patients had primary UTTCC and 62 had previous (52) or synchronous (10) transitional cell carcinoma of the bladder (BTCC). Medical records were reviewed and analyzed for possible prognostic predictors (primary tumor stage, grade, multifocality, carcinoma in situ, symptoms and signs at presentation, sex, and history of smoking). Disease specific survival and freedom from bladder recurrence were assessed with the Kaplan-Meier method, and differences between the groups were compared using the log rank test. The Cox proportional hazards regression model was used to assess the significance of each predictor. RESULTS: Disease specific death was reported for 44 patients. In a multivariate analysis using previous BTCC as a predictor (categorized as superficial, invasive or none), primary disease stage and history of BTCC were associated with disease specific survival (p = 0.001 and p = 0.018). History of BTCC grouped the patients into distinct populations in terms of disease specific survival and freedom from bladder recurrence. CONCLUSIONS: This study demonstrates that a history of BTCC (invasive or superficial) has an adverse effect on the prognosis of patients diagnosed with UTTCC independent of primary tumor stage.

Prostate cancer: detection of extracapsular extension by genitourinary and general body radiologists at MR imaging.

PURPOSE: To determine whether predictive value of endorectal magnetic resonance (MR) imaging findings in detection of prostate cancer extracapsular extension (ECE) is significantly affected by the reader's subspecialty experience. MATERIALS AND METHODS: In this cohort study, 344 consecutive patients with biopsy-proved prostate cancer underwent endorectal MR imaging followed by surgery. Likelihood of ECE described in MR imaging reports was compared with clinical predictor variables. ECE was determined from the final pathologic report on specimens resected at surgery. Readers of MR images were classified into genitourinary MR imaging radiologists (n = 4) and general body MR imaging radiologists (n = 6). For data analysis, Wilcoxon rank sum and chi(2) tests, as well as receiver operating characteristic (ROC) curves and univariate and multivariate logistic regression analyses, were used. A difference with P <.05 was considered significant. RESULTS: Univariate analysis results demonstrated that all predictors except clinical stage were significantly associated with detection of ECE in both groups of readers (P <.05). In the genitourinary MR imaging radiologist group of patients, area under the ROC curve for endorectal MR imaging findings (0.833) was larger than areas under the curves for all other predictors (0.566-0.701). In the general body MR imaging radiologist group of patients, area under the ROC curve for endorectal MR imaging findings (0.646) was not larger than areas under the curves for all other predictors (0.582-0.793). Results of multivariate analysis of two models, one with all predictors and another with all predictors except endorectal MR imaging findings, demonstrated a significant increase in area under the ROC curve with endorectal MR images interpreted by genitourinary MR imaging radiologists (P =.019 and.31, respectively). CONCLUSION: Endorectal MR imaging findings are significant predictors for detection of ECE when MR images are interpreted by genitourinary radiologists experienced with MR imaging of the prostate.

Prostate cancer: incremental value of endorectal MR imaging findings for prediction of extracapsular extension.

PURPOSE: To assess the incremental value of endorectal magnetic resonance (MR) imaging findings in addition to clinical variables for prediction of extracapsular extension (ECE) in patients with prostate cancer. MATERIALS AND METHODS: In this cohort study, 344 consecutive patients with biopsy-proved prostate cancer underwent endorectal MR imaging prior to surgery; 216 of these patients also underwent MR spectroscopic imaging. MR images were interpreted by 10 attending radiologists. The likelihood of ECE was scored retrospectively on the basis of MR imaging reports. Clinical variables included serum prostate-specific antigen (PSA) level, Gleason score, clinical stage of tumor, greatest percentage of cancer in all core biopsy specimens, percentage of cancer-positive core specimens in all core biopsy specimens, and presence of perineural invasion. For data analysis, receiver operating characteristic (ROC) curves and univariate and multivariate logistic regression analyses were used. Jackknife analysis was used for prediction of probability from a model that included clinical variables as tested comparatively with a model that included the clinical variables plus endorectal MR imaging findings. A difference with P <.05 was considered significant. RESULTS: At univariate analysis, all variables were associated with ECE. At ROC univariate analysis, endorectal MR imaging findings had the largest area under the ROC curve. At multivariate analysis, serum PSA level, percentage of cancer in all core biopsy specimens, and endorectal MR imaging findings (P =.001, P =.001, and P <.001, respectively) were predictors of ECE. Areas under ROC curve for two models, with and without endorectal MR imaging findings, were 0.838 and 0.772, respectively (P =.022). CONCLUSION: A model containing endorectal MR imaging findings has a significantly larger area under the ROC curve than a model containing only clinical variables; thus, endorectal MR imaging findings add incremental value in the prediction of ECE.