Bladder neck involvement in pathological stage pT4 radical prostatectomy specimens is not an independent prognostic factor

Factors Affecting Surgical Margin Positivity after Radical Prostatectomy in the Turkish Population: A Multicenter Study of the Urooncology Association

BACKGROUND

The prediction of positive surgical margins (SM) after radical prostatectomy (RP) is important for planning the surgical modality and adjuvant therapy in patients with prostate cancer (PCa).

OBJECTIVES

To investigate factors affecting SM positivity in patients diagnosed with PCa who underwent RP using the PCa database of the Urooncology Association (Turkey).

METHODS

Patients who underwent RP due to clinically T1c-T3 PCa and who had detailed SM data for the RP specimen were included in the study. Pathological data of 12 core transrectal ultrasound prostate biopsies and RP were evaluated. Patients were divided into 2 groups (SM positive and SM negative) according to SM status after RP. Data were compared between the groups. Factors affecting SM positivity, the number of positive SM sites, and the location of positive SM were separately evaluated with regression models.

RESULTS

A total of 2,643 patients from 6 different centers (median age: 63 years) with a prostate-specific antigen (PSA) level of 7.3 ng/mL were investigated in the study. BMI, PSA, biopsy Gleason score (GS), and perineural invasion (PNI) were found to be independent predictive factors for SM positivity and the number of positive SM locations, respectively (p < 0.05). According to the positive SM location, PSA was found to be associated with positive SM in apex, anterior prostate, and bladder neck locations. Also, according to posterolateral SM status, PNI and nerve-sparing RP (nsRP) rates were 21.3 and 44% for patients with negative posterolateral SM, and rates were 35.4 and 50.6% for patients with positive posterolateral SM, respectively (p < 0.05). In patients who underwent nsRP, positive SM was present in 22.2% of patients who did not have PNI on prostate biopsy, whereas positive SM was present in 40.6% of patients with PNI (p < 0.001). Similarly, 10.9% of patients without PNI had positive posterolateral SM, whereas 17.3% of patients with PNI had positive posterolateral SM (p = 0.031).

CONCLUSIONS

BMI, PSA, biopsy GS, and biopsy PNI positivity were found to be predictive factors affecting SM positivity. The most important factors affecting posterolateral positive SM were biopsy PNI and nsRP, indicating that the nsRP approach may cause positive SM in the posterolateral margin of the prostate (neurovascular bundle location) in patients with positive PNI on biopsy.

Evolution in Prostate Cancer Staging: Pathology Updates From AJCC 8th Edition and Opportunities That Remain

The Tumor-Nodes-Metastasis system at the core of prognostic staging has been recently updated in the American Joint Committee on Cancer (AJCC) 8th edition, published in 2016. For prostate cancer, significant changes in staging of organ-confined disease, inclusion of a new grade grouping, and provision of levels of evidence for these modifications are part of what differentiates the 8th edition AJCC from prior iterations. Herein, the rationale underlying these changes is detailed. In addition, data elements not well represented in the present system are highlighted as opportunities for fresh study that may impact future AJCC classifications.

Prostate cancer reporting and staging: needle biopsy and radical prostatectomy specimens

Prostatic adenocarcinoma remains the most common cancer affecting men. A substantial majority of patients have the diagnosis made on thin needle biopsies, most often in the absence of a palpable abnormality. Treatment choices ranging from surveillance to radical prostatectomy or radiation therapy are largely driven by the pathologic findings in the biopsy specimen. The first part of this review focuses on important morphologic parameters in needle biopsy specimens that are not covered in the accompanying articles. This includes tumor quantification as well as other parameters such a extraprostatic extension, seminal vesicle invasion, perineural invasion, and lymphovascular invasion. For those men who undergo radical prostatectomy, pathologic stage and other parameters are critical in prognostication and in determining the appropriateness of adjuvant therapy. Staging parameters, including extraprostatic extension, seminal vesicle invasion, and lymph node status are discussed here. Surgical margin status is also an important parameter and definitions and reporting of this feature are detailed. Throughout the article the current reporting guidelines published by the College of American Pathologists and the International Collaboration on Cancer Reporting are highlighted.

Improving postoperative radiotherapy following radical prostatectomy

INTRODUCTION

Prostate cancer has one of the highest incidences in the world, with good curative treatment options like radiotherapy and radical prostatectomy. Unfortunately, about 30% of the patients initially treated with curative intent will develop a recurrence and need adjuvant treatment. Five randomized trials covered the role of postoperative radiotherapy after radical prostatectomy, but there is still a lot of debate about which patients should receive postoperative radiotherapy. Areas covered: This review will give an overview on the available literature concerning post-operative radiotherapy following radical prostatectomy with an emphasis on the five randomized trials. Also, new imaging techniques like prostate-specific membrane antigen positron emission tomography (PSMA-PET) and multiparametric magnetic resonance imaging (mp-MRI) and the development of biomarkers like genomic classifiers will be discussed in the search for an improved selection of patients who will benefit from postoperative radiotherapy following radical prostatectomy. With new treatment techniques like Intensity Modulated Radiotherapy, toxicity profiles will be kept low. Expert commentary: Patients with biochemical recurrence following radical prostatectomy with an early rise in prostate-specific antigen (PSA) will benefit most from postoperative radiotherapy. In this way, patients with only high risk pathological features can avoid unnecessary treatment and toxicity, and early intervention in progressing patients would not compromise the outcome.

Margini Chirurgici Positivi Dopo una Prostatectomia Radicale

Positive surgical margins after radical prostatectomy

Positive surgical margins after radical prostatectomy: a systematic review and contemporary update

CONTEXT

The clinical significance of positive surgical margins (PSMs) in radical prostatectomy (RP) specimens and the management of affected patients remain unclear.

OBJECTIVE

To address pitfalls in the pathologic interpretation of margin status; provide an update on the incidence, predictors, and long-term oncologic implications of PSMs in the era of robot-assisted laparoscopic RP (RALRP); and suggest a practical evidence-based approach to patient management.

EVIDENCE ACQUISITION

A systematic review of the literature was performed in April 2013 using Medline/PubMed, Web of Science, and Scopus databases and the Cochrane Database of Systematic Reviews. Studies focusing on PSMs in RP pertinent to the objectives of this review were included. Particular attention was paid to publications within the last 5 yr and those concerning RALRP.

EVIDENCE SYNTHESIS

A total of 74 publications were retrieved. Standardized measures to overcome variability in the pathologic interpretation of surgical margins have recently been established by the International Society of Urological Pathology. The average rate of PSMs in contemporary RALRP series is 15% (range: 6.5-32%), which is higher in men with a more advanced pathologic stage and equivalent to the rate reported in prior open and laparoscopic prostatectomy series. The likelihood of PSMs is strongly influenced by the surgeon's experience irrespective of the surgical approach. Technical modifications using the robotic platform and the role of frozen-section analysis to reduce the margin positivity rate continue to evolve. Positive margins are associated with a twofold increased hazard of biochemical relapse, but their association with more robust clinical end points is controversial. Level 1 evidence suggests that adjuvant radiation therapy (RT) may favorably affect prostate-specific antigen recurrence rates, but whether the therapy also affects systemic progression, prostate cancer-specific mortality, and overall survival remains debatable.

CONCLUSIONS

Although positive margins in prostate cancer are considered an adverse oncologic outcome, their long-term impact on survival is highly variable and largely influenced by other risk modifiers. Adjuvant RT appears to be effective, but further study is required to determine whether early salvage RT is an equivalent alternative.

Evaluation of the 7th American Joint Committee on cancer TNM staging system for prostate cancer in point of classification of bladder neck invasion

OBJECTIVE

To assess the validity of the 7th edition of the American Joint Committee on Cancer TNM staging system for prostate cancer, paying special attention to bladder neck invasion, in an Asian population.

METHODS

Clinicopathologic data of 368 men who underwent radical prostatectomy between 2003 and 2011 at our institution were reviewed. The main interest of this study was to confirm that both isolated positive bladder neck margin and positive bladder neck margin associated with other surgical margin have more favorable biochemical outcomes than seminal vesicle invasion (pT3b).

RESULTS

The 3-year biochemical recurrence-free survival for men with organ confined disease, extraprostatic extension, isolated positive bladder neck margin, positive bladder neck margin with other surgical margin and seminal vesicle invasion was 88.9, 74.8, 51.2, 19.4 and 18.8%, respectively. On multivariate analysis, the increased risk of progression associated with an isolated positive bladder neck margin (hazard ratio 4.34, 95% confidence interval 1.40-13.46, P = 0.011) was less than that of seminal vesicle invasion (hazard ratio 9.67, 95% confidence interval 3.70-25.25, P < 0.001). As for the positive bladder neck margin with other surgical margin, the increased risk of progression (hazard ratio 9.32, 95% confidence interval 3.50-24.82, P < 0.001) was similar to that of men with seminal vesicle invasion.

CONCLUSIONS

In our study, men with isolated positive bladder neck margin and positive bladder neck margin plus other surgical margin had no worse biochemical outcomes than those with seminal vesicle invasion (pT3b). It is reasonable to classify prostate cancer with bladder neck invasion (the 6th American Joint Committee on Cancer edition pT4 category) into the 7th edition pT3 category.

Reducing the influence of b-value selection on diffusion-weighted imaging of the prostate: evaluation of a revised monoexponential model within a clinical setting

PURPOSE

To compare the accuracy of standard and revised monoexponential models of diffusion-weighted magnetic resonance imaging (DW-MRI) data for differentiating malignant from benign prostate tissue, using surgical pathology as the reference standard.

MATERIALS AND METHODS

The Institutional Review Board waived informed consent for this Health Insurance Portability and Accountability Act (HIPAA)-compliant, retrospective study of 46 patients (median age = 61 years; range: 42-85 years) who underwent DW-MRI between May and December 2008 before radical prostatectomy for biopsy-proven prostate cancer, had no prior treatment, and had whole-mount step-section pathology maps available showing at least one peripheral zone (PZ) lesion >0.1 cm(3) . DW-MRI data were obtained for b-values of 0, 400, and 700 s/mm(2) . Apparent diffusion coefficients (ADCs) were estimated from PZ regions of interest (ROIs) on b = 0, 700 and b = 0, 400 s/mm(2) images, using a standard monoexponential model. The true diffusion coefficient (D) and perfusion fraction (f) were measured using a revised monoexponential model incorporating all three b-values. Areas under receiver operating characteristic curves (AUCs) were calculated to assess the accuracy of individual parameters and a logistic regression model combining D and f (D+f) in distinguishing malignant ROIs; P < 0.05 denoted significance.

RESULTS

ADC(400) (AUC = 0.81, P < 0.0001), ADC(700) (AUC = 0.79, P < 0.0001), D (AUC = 0.71, P = 0.0001) and D + f distinguished malignant from benign ROIs (AUC = 0.82, P < 0.0001), but f did not (AUC = 0.56, P = 0.28); D + f was significantly more accurate than D (P = 0.016) but not more accurate than ADC(400) (P = 0.26) or ADC(700) (P = 0.12).

CONCLUSION

The true diffusion coefficient provides an additional DW-MRI parameter for distinguishing prostate cancer that is less influenced than the ADC by b-value selection.

Length of site-specific positive surgical margins as a risk factor for biochemical recurrence following radical prostatectomy

OBJECTIVES

Positive surgical margins (PSM) have been associated with biochemical recurrence (BCR) after radical prostatectomy, but the significance of PSM length and location are debated. We assessed the impact of PSM lengths at specific locations for BCR in an open radical prostatectomy series.

METHODS

Detailed clinical and pathological data were collected from 117 post-prostatectomy patients with PSM from 1984 to 2004 at our institution. PSM locations were classified as apex, mid-gland, base, bladder neck, and anterior fibromuscular region with lengths measured at each site. Aggregate PSM length was obtained by summing lengths of all PSM areas in contact with the inked surface. BCR was defined as serum prostate specific antigen level 0.2 ng/mL or greater. Cox proportional hazards regression analyses of PSM lengths were conducted either as a continuous or categorical variable relative to location as a predictor of BCR.

RESULTS

Multivariate analyses demonstrated that as a continuous variable, PSM length at the anterior fibromuscular region (Hazard ratio [HR] = 1.17; P = 0.027) and bladder neck (HR = 1.29; P = 0.046) were significant predictors for BCR. As a categorical variable, PSM length ≥ 2 mm at the anterior fibromuscular area was significant for BCR (HR = 3.02; P = 0.036). Increasing Gleason grade and positive lymph node status were also found to be significant independent predictors for BCR.

CONCLUSION

PSM length at the anterior fibromuscular region (continuous and categorical) and the bladder neck (continuous) was significantly associated with BCR. Site-specific PSM length, along with Gleason grade and lymph node status, can be predictive of BCR and assist in risk stratification of patients with PSM following radical prostatectomy.

Semi-automatic deformable registration of prostate MR images to pathological slices

PURPOSE

To present a semi-automatic deformable registration algorithm for co-registering T2-weighted (T2w) images of the prostate with whole-mount pathological sections of prostatectomy specimens.

MATERIALS AND METHODS

Twenty-four patients underwent 1.5 Tesla (T) endorectal MR imaging before radical prostatectomy with whole-mount step-section pathologic analysis of surgical specimens. For each patient, the T2w imaging containing the largest area of tumor was manually matched with the corresponding pathologic slice. The prostate was co-registered using a free-form deformation (FFD) algorithm based on B-splines. Registration quality was assessed through differences between prostate diameters measured in right-left (RL) and anteroposterior (AP) directions on T2w images and pathologic slices and calculation of the Dice similarity coefficient, D, for the whole prostate (WP), the peripheral zone (PZ) and the transition zone (TZ).

RESULTS

The mean differences in diameters measured on pathology and MR imaging in the RL direction and the AP direction were 0.49 cm and -0.63 cm, respectively, before registration and 0.10 cm and -0.11 cm, respectively, after registration. The mean D values for the WP, PZ and TZ, were 0.76, 0.65, and 0.77, respectively, before registration and increased to 0.91, 0.76, and 0.85, respectively, after registration. The improvements in D were significant for all three tissues (P < 0.001 for all).

CONCLUSION

The proposed semi-automatic method enabled successful co-registration of anatomical prostate MR images to pathologic slices.

International Society of Urological Pathology (ISUP) consensus conference on handling and staging of radical prostatectomy specimens: rationale and organization

The 2009 International Society of Urological Pathology consensus conference in Boston, made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. The activities of the conference were coordinated through five workgroups. The results are presented in five separate reports covering (1) specimen handling, (2) T2 substaging and prostate cancer volume, (3) extraprostatic extension, lymphovascular invasion and locally advanced disease, (4) seminal vesicles and lymph node metastases and (5) surgical margins. In this introductory article we describe some novel features of the organization of the consensus process. Following the completion of a pre-meeting survey conference, participants discussed and voted on 43 specific issues of contention relating to the pathological reporting of radical prostatectomy specimens. Consensus, defined as agreement by at least 65% of participants present, was achieved for 30 questions.

International Society of Urological Pathology (ISUP) Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens. Working group 3: extraprostatic extension, lymphovascular invasion and locally advanced disease

The International Society of Urological Pathology Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens in Boston made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. Issues relating to extraprostatic extension (pT3a disease), bladder neck invasion, lymphovascular invasion and the definition of pT4 were coordinated by working group 3. It was agreed that prostate cancer can be categorized as pT3a in the absence of adipose tissue involvement when cancer bulges beyond the contour of the gland or beyond the condensed smooth muscle of the prostate at posterior and posterolateral sites. Extraprostatic extension can also be identified anteriorly. It was agreed that the location of extraprostatic extension should be reported. Although there was consensus that the amount of extraprostatic extension should be quantitated, there was no agreement as to which method of quantitation should be employed. There was overwhelming consensus that microscopic urinary bladder neck invasion by carcinoma should be reported as stage pT3a and that lymphovascular invasion by carcinoma should be reported. It is recommended that these elements are considered in the development of practice guidelines and in the daily practice of urological surgical pathology.

Are histopathological features of prostate cancer lesions associated with identification of extracapsular extension on magnetic resonance imaging?

OBJECTIVE

To assess the effect of histopathological lesion characteristics on the sensitivity of magnetic resonance imaging (MRI) for per-lesion identification of extracapsular extension (ECE) of prostate cancer.

PATIENTS AND METHODS

The study included 176 patients (median age 58.9 years, range 38-77) who underwent endorectal MRI before radical prostatectomy between January 2001 and July 2004, had no previous treatment and had whole-mount step-section pathological specimens showing at least one capsule-abutting lesion. The likelihood of ECE of capsule-abutting lesions was retrospectively scored from 1 to 5 based on radiologists' prospective MRI interpretations. Generalized estimating equation regression models were used to determine the effect of the following histological variables on the sensitivity of MRI for identifying ECE of capsule-abutting lesions: maximum diameter, largest perpendicular diameter (LPD), bi-dimensional diameter product, Gleason grade, and zonal extent.

RESULTS

On histopathology, 339 capsule-abutting lesions were found, including 54 with ECE. MRI correctly identified ECE in 36/54 capsule-abutting lesions, including nine of 18 with focal ECE and 27/36 with established ECE, giving sensitivities (95% confidence interval) of 67 (53-78)%, 50 (27-73)% and 75 (58-87)%, respectively. MRI incorrectly identified ECE in 27/285 (9%) capsule-abutting lesions without ECE. MRI sensitivity for per-lesion ECE identification was significantly associated only with histopathological LPD (P = 0.009). Fifty-one patients (29%) had ECE. MRI had a sensitivity (95% confidence interval) of 69 (54-81)% and specificity of 90 (83-94)% for per-patient ECE identification.

CONCLUSIONS

The sensitivity of MRI in per-lesion identification of prostate cancer ECE is significantly associated with the lesion LPD at histopathology.

The significance of a positive bladder neck margin after radical prostatectomy: the American Joint Committee on Cancer Pathological Stage T4 designation is not warranted

PURPOSE

The American Joint Committee on Cancer currently designates invasion of the bladder neck as a pT4 lesion. However, retrospective analyses have not demonstrated biochemical recurrence-free survival after radical prostatectomy to be consistent with other T4 lesions. We examined biochemical recurrence-free survival and cancer specific survival in men with a positive bladder neck margin.

MATERIALS AND METHODS

Of nearly 17,000 patients in the Johns Hopkins Institutional radical prostatectomy database (1982 to 2008) 198 (1.2%) were identified with a positive bladder neck margin. Kaplan-Meier analyses were used to evaluate biochemical recurrence-free survival and cancer specific survival. A multivariate proportional hazards model predicting biochemical recurrence-free survival and cancer specific survival was fit with prostate specific antigen, Gleason sum and pathological stage to determine the significance of a positive bladder neck margin.

RESULTS

Of the 198 men with a positive bladder neck margin 79 had an isolated bladder neck margin without seminal vesicle or lymph node involvement. The 12-year biochemical recurrence-free survival of men with organ confined disease, extraprostatic extension, seminal vesicle invasion and lymph node involvement without a positive bladder neck margin was 91.1%, 61.1%, 24.5% and 8.1%, respectively. For men with a positive bladder neck margin and those with an isolated positive bladder neck margin biochemical recurrence-free survival was 16.8% and 37.1%, respectively. The 12-year cancer specific survival for men with organ confined disease, extraprostatic extension, seminal vesicle invasion and lymph node involvement without a positive bladder neck margin was 93.5%, 89.0%, 77.0% and 66.8%, respectively. For men with a positive bladder neck margin and those with an isolated positive bladder neck margin cancer specific survival was 78.2% and 92.5%, respectively. A positive bladder neck margin was not a significant predictor of outcome (p = 0.4) on multivariable analysis.

CONCLUSIONS

The incidence of an isolated positive bladder neck margin is low. Men with an isolated positive bladder neck margin after radical prostatectomy experienced a 12-year biochemical recurrence-free survival of 37% and cancer specific survival of 92%, similar to patients with seminal vesicle invasion (pT3b) and extraprostatic extension (pT3a), respectively. The existing American Joint Committee on Cancer classification for prostate cancer should be reconsidered.

The prognostic significance of bladder neck invasion in prostate cancer: is microscopic involvement truly a T4 disease?

Since the widespread of prostate-specific antigen-based screening, prostate cancer at clinical stage T4 has become rare. Most bladder invasion is actually detected on radical prostatectomy specimens as a microscopic bladder neck involvement (BNI). The 2002 Tumour-Node-Metastasis (TNM) classification system classified prostate cancer with BNI within a unified pT4 category and rendered it equivalent to invasion into the pelvic wall musculature or external sphincter; this decision is controversial. Various series have assessed the clinical relevance and the effect of BNI on prognosis. This evidence-based review provides evidence that BNI should be assigned within the subset of pT3 stage, and that further improvement of the actual TNM staging system should be considered. However, BNI remains strongly associated with adverse pathology and should be regarded as a factor that worsens the prognosis of the underlying tumour stage.

Radical retropubic prostatectomy for prostate cancer with microscopic bladder neck involvement: survival and prognostic implications

OBJECTIVE

To report the oncological outcome of 106 patients who had locally advanced prostate cancer with microscopic bladder neck invasion, identified in a series of 1129 patients surgically treated with retropubic radical prostatectomy over a 12-year period.

PATIENTS AND METHODS

All specimens were reviewed. Microscopic bladder neck invasion was defined as the presence of neoplastic cells within the smooth muscle bundles of the bladder neck, with no accompanying prostatic glandular tissue on the corresponding slide. Survival was analysed for different subgroups in relation to several variables.

RESULTS

The follow-up (median 7.2 years, mean 6.68, range 0.3-14) was available for 106 patients with microscopic bladder neck invasion. Seminal vesicle invasion was present in 69.8% of the cases, lymph node involvement in 29.2%, apex infiltration in 31.8%, and positive surgical margins in 23.6%. Biochemical progression occurred in 61 (57.5%) patients, and 25 of them died from cancer. The mean (sd) biochemical progression-free survival was 0.68 (0.05), 0.59 (0.05), 0.40 (0.05) and 0.38 (0.05) at 1, 2, 5 and 10 years, respectively. Age, Gleason score and lymph node invasion were independent prognostic factors on multivariate analysis. Overall and cancer-specific survival rates were 0.75 (0.04) and 0.80 (0.04) at 5 years and 0.57 (0.04) and 0.75 (0.04) at 10 years, respectively. Univariate analysis showed that seminal vesicle invasion, lymph node involvement and surgical Gleason score > or =8 significantly increased the risk of death. On multivariate analysis only the surgical Gleason score had an independent prognostic role with regard to overall survival (P = 0.01; odds ratio 2.82, 95% confidence interval 1.2-6.4) and cancer-specific survival (P < 0.001; 8.6, 2.5-28.8).

CONCLUSIONS

In this series, overall and cancer-specific survival rates were comparable to those reported for surgically treated cT3 prostate cancers. The lack of need for external urinary diversion during the entire follow-up significantly contributed to the patients' quality of life.

Combined T2-weighted and diffusion-weighted MRI for diagnosis of urinary bladder invasion in patients with prostate carcinoma

PURPOSE

To retrospectively determine the diffusion-weighted imaging (DWI) characteristics and apparent diffusion coefficient (ADC) values of prostate carcinoma (PCa) with urinary bladder invasion, and to compare the accuracy of T2-weighted MRI alone and T2 combined with DWI for predicting urinary bladder invasion.

MATERIALS AND METHODS

Sixty-eight patients with proven PCa were diagnosed with urinary bladder invasion after conventional magnetic resonance imaging (MRI) and DWI (b value = 750 sec/mm(2)) examinations. All the 68 cases underwent cystoscopy examination. DWI appearances of all urinary bladder invasion and a normal urinary bladder wall were analyzed, and their ADC values were measured. T2 images alone and then T2 images combined with DWI were scored for the likelihood of urinary bladder invasion on the basis of radiologists' written reports. The area under the receiver operating characteristic curve (AUC) was used to assess accuracy. Statistical significance was inferred at P < 0.05.

RESULTS

After cystoscopy examination, 45 (66%) of 68 cases were pathologically proven urinary bladder invasion. The mean ADCs for urinary bladder invasion and normal urinary bladder wall were (0.963 +/- 0.155) x 10(-3)mm(2)/sec and (1.517 +/- 0.103) x 10(-3)mm(2)/sec, respectively. The ADC values of urinary bladder invasion were significantly lower than those of normal urinary bladder wall (P = 0.000). The AUC for T2-weighted imaging plus DW imaging (0.861) was significantly larger than that for T2-weighted imaging alone (0.734) or for DW imaging alone (0.703) (P < 0.001).

CONCLUSION

Urinary bladder invasion had lower ADC values compared with normal urinary bladder wall. T2 images plus DWI is significantly better than T2-weighted imaging alone in the detection of urinary bladder invasion in patients with PCa.

Prostate tumor volume measurement with combined T2-weighted imaging and diffusion-weighted MR: correlation with pathologic tumor volume

PURPOSE

To retrospectively determine the accuracy of diffusion-weighted (DW) magnetic resonance (MR) imaging for identifying cancer in the prostate peripheral zone (PZ) and to assess the accuracy of tumor volume measurements made with T2-weighted imaging and combined T2-weighted and DW MR imaging by using surgical pathologic examination as the reference standard.

MATERIALS AND METHODS

The institutional review board issued a waiver of informed consent for this HIPAA-compliant study. Forty-two patients underwent endorectal MR at 1.5 T before undergoing radical prostatectomy for prostate cancer and had at least one PZ tumor larger than 0.1 cm(3) at surgical pathologic examination. On T2-weighted images, an experienced radiologist outlined suspected PZ tumors. Two apparent diffusion coefficient (ADC) cutoff values were identified by using the Youden index and published literature. Image cluster analysis was performed on voxels within the suspected tumor regions. Associations between volume measurements from imaging and from pathologic examination were assessed by using concordance correlation coefficients (CCCs). The sensitivity and specificity of ADCs for identifying malignant PZ voxels were calculated.

RESULTS

In identifying malignant voxels, respective ADC cutoff values of 0.0014 and 0.0016 mm(2)/sec yielded sensitivity of 82% and 95% and specificity of 85% and 65%, respectively. Sixty PZ cancer lesions larger than 0.1 cm(3) were found at pathologic examination; 43 were detected by the radiologist. CCCs between imaging and pathologic tumor volume measurements were 0.36 for T2-weighted imaging, and 0.46 and 0.60 for combined T2-weighted and DW MR imaging with ADC cutoffs of 0.0014 and 0.0016 mm(2)/sec, respectively; the CCC of combined T2-weighted and DW MR imaging (ADC cutoff, 0.0016 mm(2)/sec) was significantly higher (P = .006) than that of T2-weighted imaging alone.

CONCLUSION

Adding DW MR to T2-weighted imaging can significantly improve the accuracy of prostate PZ tumor volume measurement.

SUPPLEMENTAL MATERIAL

http://radiology.rsnajnls.org/cgi/content/full/252/2/449/DC1.

[Clinical study of radical prostatectomy for prostate cancer from a single institution]

PURPOSE

To investigate the outcomes for single institution with prostate cancer treated with radical prostatectomy (RP).

MATERIALS AND METHODS

A retrospective analysis was performed on 406 patients who underwent RRP from January 1991 to December 2005 for cT1-3N0M0 prostate cancer. To evaluate the change of the patient background, we divided the 15 years into the 5 periods whose span was 3 years each and examined. Biochemical recurrence was defined as a prostate-specific antigen (PSA) of > or = 0.2 ng/ml. Clinical recurrence was defined as metastases or local recurrence. Actual probability of cancer specific mortality was estimated using the Kaplan-Meier method. The Log rank test was used to determine statistical difference between actual curves. Preoperative parameters analyzed were patient age, preoperative PSA, clinical stage, Gleason score, and Neoadjuvant hormonal therapy. Multivariate analyses (logistic regression and Cox proportional hazard model) for the dependent variables (organ-confined prostate cancer, clinical recurrence free survival and cancer specific mortality) were performed. Perioperative complications between cT1/2 with cT3 were compared.

RESULTS

The number of the operation increased every period. High recurrence risk group and cT3 were tended to decrease. Median follow-up and median patient age were 55 month and 69 year. Of the 406 men, 35 (8.6%) developed clinical recurrence, 15 men (3.7%) died from prostate cancer within the follow-up period. For pT0/2, pT3a, pT3b and pN +, the 10-yr cancer specific survival rate was 100%, 92%, 81% and 67%, respectively. Preoperative PSA (p < 0.0001), clinical stage (p = 0.004), Gleason score (p < 0.0001) and neoadjuvant hormone therapy (p = 0.0003) are predictive variables for organ confined prostate cancer. Preoperative PSA (p = 0.002) and clinical stage (p = 0.03) are prognostic variables for cancer specific mortality. There was significant difference in surgery time (p = 0.04) and blood loss (p = 0.0007) in cT1/2 cases compared with cT3 cases.

CONCLUSION

The number of the operation increased every period. High recurrence risk group and cT3 were tended to decrease. Neoadjuvant hormone therapy prior to prostatectomy was a significant improvement in the organ confined rates. However neoadjuvant hormone therapy did not improve patient prognosis. Preoperative PSA and clinical stage are prognostic variable for cancer specific mortality.

Bladder neck involvement as pT4 disease in prostate cancer: implications for prognosis and patient surveillance

Since the use of prostate-specific antigen screening has become widespread, prostate cancer at clinical T4 stage has become rare. Most bladder invasion is actually detected on radical prostatectomy specimens as a microscopic bladder neck involvement (BNI). The 2002 TNM classification system classified prostate cancer with BNI within a unified pT4 category, and rendered it equivalent to invasion into pelvic wall musculature or external sphincter. This decision is controversial. Various series have studied the clinical relevance and the impact of BNI on prognosis. Our evidence-based review provides support to the assignment of BNI within the subset of pT3 stage, and suggests that further improvement of the actual TNM staging system should be considered. However, BNI remains strongly associated with adverse pathology and should be regarded as a factor that worsens the prognosis of the underlying tumor stage.

Focal treatment or observation of prostate cancer: pretreatment accuracy of transrectal ultrasound biopsy and T2-weighted MRI

OBJECTIVES

To test the hypothesis that men with prostate cancer (PCA) and preoperative disease features considered favorable for focal treatment would be accurately characterized with transrectal biopsy and prostate magnetic resonance imaging (MRI) by performing a retrospective analysis of a selected cohort of such patients treated with radical prostatectomy (RP).

METHODS

A total of 202 patients with PCA who had preoperative MRI and low-risk biopsy criteria (no Gleason grade 4/5, 1 involved core, < 2 mm, PSA density < or = 0.10, clinical stage < or = T2a) were included in the study. Indolent RP pathology was defined as no Gleason 4/5, organ confined, tumor volume < 0.5 mL, and negative surgical margins. MRI ability to locate and determine the tumor extent was assessed.

RESULTS

After RP, 101 men (50%) had nonindolent cancer. Multifocal and bilateral tumors were present in 81% and 68% of patients, respectively. MRI indicated extensive disease in 16 (8%). MRI sensitivity to locate PCA ranged from 2% to 20%, and specificity from 91% to 95%. On univariate analysis, MRI evidence of extracapsular extension (P = .027) and extensive disease (P = .001) were associated with nonindolent cancer. On multivariate analysis, only the latter remained as significant predictor (P = .0018).

CONCLUSIONS

Transrectal biopsy identified men with indolent tumors favorable for focal treatment in 50% of cases. MRI findings of extracapsular extension and extensive tumor involving more than half of the gland are associated with unfavorable features, and may be useful in excluding patients from focal treatment. According to these data, endorectal MRI is not sufficient to localize small tumors for focal treatment.

The clinical significance and therapeutic implications of extraprostatic invasion

Invasion of the prostatic margin by cancer establishes a higher risk of disease progression and treatment failure depending upon its extent and other clinical factors. Pathological stage is the most important single prognostic indicator, but determined reliably only in patients having radical prostatectomy. Tumour beyond the prostatic margin or its invasion into the seminal vesicle defines the local stage category as T3, and when confirmed by pathological examination the extent of prostatic margin involvement has prognostic significance. Prediction of extraprostatic invasion may influence therapeutic decisions, but can be difficult to determine for the individual patient prior to treatment. In some individuals having radical prostatectomy, the finding of extraprostatic invasion is unsuspected, and fortunately for the majority of these men the treatment remains curative. On the other hand, when extraprostatic invasion is suspected prior to or at surgery, wide excision may be necessary to achieve negative surgical margins, with other factors contributing independently to the likelihood of subsequent progression. Radiotherapy is an effective alternative treatment for clinical stage T3 and high-risk clinically localized cancer. Recent technological advances and use of combination modality treatment with radiation and hormone manipulation have improved survival outcomes and reduced side-effects. Radiation also has its place as adjuvant treatment following radical prostatectomy in high-risk disease, or as salvage following PSA recurrence, with ongoing trials evaluating potential benefit and toxicity. For clinically localised stage T3 prostate cancer, treatment with surgery or radiotherapy may be highly effective, but multimodality interventions are increasingly being used for primary treatment where clinical assessment indicates that there would otherwise be a high risk for disease progression and therapeutic failure.

Microscopic bladder neck involvement by prostate carcinoma in radical prostatectomy specimens is not a significant independent prognostic factor

The independent prognostic importance of microscopic bladder neck involvement by prostate cancer in radical prostatectomy is questionable. We studied a cohort of 1845 patients to determine the significance of microscopic bladder neck involvement. Bladder neck involvement was defined as prostate cancer present within the coned bladder neck. We further categorized the cases as 'true bladder neck involvement' and 'false bladder neck involvement.' True bladder neck involvement required prostate cancer within thick smooth muscle bundles without intermixed benign prostatic glands. False bladder neck involvement was characterized by prostate cancer intermixed with benign prostatic glands. Bladder neck involvement was analyzed in relation to preoperative serum prostate-specific antigen (PSA) level, extraprostatic extension, seminal vesicle involvement, positive surgical margin, lymph node involvement, radical prostatectomy Gleason score, and tumor volume. Of the 90 patients (4.9%) with microscopic bladder neck involvement, 63 were further classified as true bladder neck involvement and 27 as false bladder neck involvement. In univariate model, both types of bladder neck involvement (P<0.001), true (P<0.001), and false (P=0.040), were significantly associated with increased PSA-recurrence risk compared to bladder neck negative cases. In multivariate model the PSA-recurrence relative risk associated with bladder neck involvement (true or false) was not a significant independent prognostic factor. Extraprostatic extension, seminal vesicle involvement, positive surgical margin, lymph node involvement, PSA, and Gleason score were significant independent predictors of PSA recurrence. The time to biochemical recurrence in patients with bladder neck involvement was similar to that of pT2 with positive surgical margin or pT3a with negative surgical margin patients (Kaplan-Meier curves). Bladder neck involvement was associated with other adverse pathologic features, but was not an independent predictor of PSA recurrence. In view of the previous and current data, the staging system for bladder neck involvement should be revised and patients may be best categorized as having pT3a disease.

Positive surgical margins in radical prostatectomy: outlining the problem and its long-term consequences

CONTEXT

This review focuses on positive surgical margins (PSM) in radical prostatectomy (RP).

OBJECTIVE

To address the etiology, incidence, and oncologic impact of PSM and discuss technical points to help surgeons minimize their positive margin rate. An evidence-based approach to assist clinicians in counseling patients with a PSM is provided.

EVIDENCE ACQUISITION

A literature search in English was performed using the National Library of Medicine database and the following key words: prostate cancer, surgical margins, and radical prostatectomy. Seven hundred sixty-eight references were scrutinized, and 73 were selected for rigorous review based on their pertinence, study size, and overall contribution to the field.

EVIDENCE SYNTHESIS

In contemporary series, PSM are reported in 11-38% of patients undergoing RP. Although variability exists in the pathologic interpretation of surgical margins, PSM are associated with an increased hazard of biochemical recurrence (BCR) and local disease recurrence as well as the need for secondary cancer treatment. A posterolateral PSM appears to confer the greatest risk of recurrence, whereas the prognostic significance of positive apical margins remains controversial. The role of preoperative imaging and intraoperative frozen section analysis are being investigated to reduce margin positivity rates. Level-1 evidence indicates that adjuvant radiotherapy (RT) in men with PSM reduces BCR rates and clinical progression and possibly improves overall survival (OS).

CONCLUSIONS

PSM in RP specimens are uniformly considered an adverse outcome. Regardless of approach (open or laparoscopic), attention to surgical detail is essential to minimize rates. For patients with a PSM destined to experience a cancer recurrence, RT is the only established treatment with curative potential. A randomized trial in patients with PSM comparing immediate postoperative RT to salvage RT is critically needed before definitive recommendations can be made.

Pretreatment endorectal magnetic resonance imaging and magnetic resonance spectroscopic imaging features of prostate cancer as predictors of response to external beam radiotherapy

PURPOSE

To evaluate whether pretreatment combined endorectal magnetic resonance imaging (MRI) and magnetic resonance spectroscopic imaging (MRSI) findings are predictive of outcome in patients who undergo external beam radiotherapy for prostate cancer.

METHODS AND MATERIALS

We retrospectively identified 67 men with biopsy-proven prostate cancer who underwent combined endorectal MRI and MRSI at our institution between January 1998 and October 2003 before whole-pelvis external beam radiotherapy. A single reader recorded tumor presence, stage, and metabolic abnormality at combined MRI and MRSI. Kaplan-Meier survival and Cox univariate and multivariate analyses explored the relationship between clinical and imaging variables and outcome, using biochemical or metastatic failure as endpoints.

RESULTS

After a mean follow-up of 44 months (range, 3-96), 6 patients developed both metastatic and biochemical failure, with an additional 13 patients developing biochemical failure alone. Multivariate Cox analysis demonstrated that the only independent predictor of biochemical failure was the volume of malignant metabolism on MRSI (hazard ratio [HR] 1.63, 95% confidence interval [CI] 1.29-2.06; p < 0.0001). The two independent predictors of metastatic failure were MRI tumor size (HR 1.34, 95% CI 1.03-1.73; p = 0.028) and the finding of seminal vesicle invasion on MRI (HR 28.05, 95% CI 3.96-198.67; p = 0.0008).

CONCLUSIONS

In multivariate analysis, MRI and MRSI findings before EBRT in patients with prostate cancer are more accurate independent predictors of outcome than clinical variables, and in particular, the findings of seminal vesicle invasion and extensive tumor predict a worse prognosis.

Prostate cancer: identification with combined diffusion-weighted MR imaging and 3D 1H MR spectroscopic imaging--correlation with pathologic findings

PURPOSE

To retrospectively measure the mean apparent diffusion coefficient (ADC) with diffusion-weighted magnetic resonance (MR) imaging and the mean metabolic ratio (MET) with three-dimensional (3D) hydrogen 1 ((1)H) MR spectroscopic imaging in regions of interest (ROIs) drawn over benign and malignant peripheral zone (PZ) prostatic tissue and to assess ADC, MET, and combined ADC and MET for identifying malignant ROIs, with whole-mount histopathologic examination as the reference standard.

MATERIALS AND METHODS

The institutional review board approved this HIPAA-compliant retrospective study and issued a waiver of informed consent. From among 61 consecutive patients with prostate cancer, 38 men (median age, 61 years; range, 42-72 years) who underwent 1.5-T endorectal MR imaging before radical prostatectomy and who fulfilled all inclusion criteria of no prior hormonal or radiation treatment and at least one PZ lesion (volume, >0.1 cm(3)) at whole-mount pathologic examination were included. ADC maps were generated from diffusion-weighted MR imaging data, and MET maps of (choline plus polyamine plus creatine)/citrate were calculated from 3D (1)H MR spectroscopic imaging data. ROIs in the PZ identified by matching pathologic slides with T2-weighted images were overlaid on MET and ADC maps. Areas under the receiver operating characteristic curves (AUCs) were used to evaluate accuracy.

RESULTS

The mean ADC +/- standard deviation, (1.39 +/- 0.23) x 10(-3) mm(2)/sec, and mean MET (0.92 +/- 0.32) for malignant ROIs differed significantly from the mean ADC, (1.69 +/- 0.24) x 10(-3) mm(2)/sec, and mean MET (0.73 +/- 0.18) for benign ROIs (P < .001 for both). In distinguishing malignant ROIs, combined ADC and MET (AUC = 0.85) performed significantly better than MET alone (AUC = 0.74; P = .005) and was also better than ADC alone (AUC = 0.81), although the difference was not statistically significant (P = .09).

CONCLUSION

The combination of ADC and MET performs significantly better than MET for differentiating between benign and malignant ROIs in the PZ.

Assessment of biologic aggressiveness of prostate cancer: correlation of MR signal intensity with Gleason grade after radical prostatectomy

PURPOSE

To retrospectively investigate whether the signal intensity (SI) of prostate cancer on T2-weighted magnetic resonance (MR) images correlates with the Gleason grade at whole-mount step-section pathologic evaluation after radical prostatectomy.

MATERIALS AND METHODS

The institutional review board approved and issued a waiver of informed consent for this HIPAA-compliant study of 74 patients (median age, 57.5 years; range, 32-72 years) who underwent endorectal MR imaging before radical prostatectomy, with subsequent whole-mount step-section pathologic evaluation, between January 2001 and July 2004. Inclusion criteria were that they had: no prior treatment; at least one lesion of uniform Gleason grade 3 or 4 or with Gleason grade 5 components, with a bidimensional diameter product of 20 mm2 or greater; no high SI on T1-weighted MR images indicative of postbiopsy changes; and an interval of more than 4 weeks between biopsy and MR imaging. SI of prostate tumors, nontumor prostatic tissue, and internal obturator muscles was measured on uncorrected and corrected T2-weighted MR images. Correlations between Gleason grades and SI ratios were assessed by using generalized estimating equations. SI ratios in peripheral zone (PZ) and transition zone (TZ) lesions of the same Gleason grade were compared with an unpaired t test.

RESULTS

Seventy-nine Gleason grade 3, eight Gleason grade 4, and four mixed Gleason grades 4 and 5 lesions identified at pathologic evaluation were analyzed. Gleason grade correlated significantly with tumor-muscle SI ratio for PZ tumors on corrected and uncorrected images (P = .006 and <.001, respectively). Higher Gleason grades were associated with lower tumor-muscle SI ratios. Nontumor-muscle SI ratios did not correlate with patients' Gleason grades. Tumor-muscle SI ratios were lower in TZ than in PZ tumors (P < .001).

CONCLUSION

Higher Gleason grades were associated with lower tumor-muscle SI ratios on T2-weighted MR images. SI evaluation on T2-weighted MR images may facilitate noninvasive assessment of prostate cancer aggressiveness.

Anatomy of the anterior prostate and extraprostatic space: a contemporary surgical pathology analysis

Over 25 years ago, McNeal described a model of prostatic zonal anatomy based on autopsy dissections in various planes. As opposed to the cone-shaped organ seen in vivo, radical prostatectomy specimens are typically spherical, owing to tissue contraction at surgical removal and subsequent processing. Sectioning from apex to base yields topography at the Surgical Pathology "sign-out" that may vary from McNeal's descriptions. There are no in depth studies of anterior prostatic anatomic variability, including the periurethral region, peripheral (PZ) and transition (TZ) zones, anterior fibromuscular stroma (AFMS), and anterior extraprostatic space (EPS) using modern prosecting techniques. Detailed analysis of 197 entirely submitted, whole-mounted radical prostatectomy specimens focused on differences in zonal anatomy from apex through base, the relationship of AFMS to PZ and TZ, and the nature of the anterior EPS revealed features that may have significant impact on determination of zonal origin and pathologic staging of anteriorly situated prostate cancer. Among these observations are the predominant nature of the anterior PZ at the apex and the potential for its broad contact with the AFMS at this location, the differing volumes and location of the TZ in prostates with and without benign prostatic hyperplasia, and the composition of the anterior EPS, including adipose tissue, blood vessels, and skeletal muscle at the apex varying to include medium to large smooth muscle bundles at the base.

Invasion of bladder neck after radical prostatectomy: one definition for different outcomes

The aim of the study was to evaluate factors of progression after radical prostatectomy in patients with bladder neck invasion (BNI). From 1988 to 2006, 1395 patients underwent radical prostatectomy, 120 (8.6%) had microscopic BNI (pT4 N0, TNM 2002). Group 1 was defined as BNI alone, group 2 as BNI plus extracapsular extension and group 3 as BNI plus seminal vesicle invasion (SVI). Postoperative follow-up data were obtained through routine serum prostate-specific antigen (PSA) and digital rectal examination. Biochemical progression was defined as a single detectable PSA level postoperatively (>0.2 ng ml(-1)). Groups 1, 2 and 3 included 38 (31%), 35 (30%) and 47 (39%) patients, respectively. Preoperative PSA (11.1 vs 24.7 and 23.3 ng ml(-1), P=0.01), biopsy Gleason score (5 vs 6 and 6, P=0.003) and specimen Gleason score (6 vs 7 and 7, P=0.02) were statistically different between three groups. None of the patients had a specimen Gleason score >or=8 in group 1. After a mean follow-up of 27 months, 51 (42.5%) patients had biochemical progression. The 5-year progression-free survival was 87, 53 and 17% for groups 1, 2 and 3, respectively (P<0.001). Within pT4 prostate cancer, those tumors with isolated microscopic BNI appear to have better prognosis than those with associated extracapsular extension and/or seminal vesicle invasion, and should be distinguished in TNM classification.

The clinical features of anterior prostate cancers

OBJECTIVE

To identify the clinical characteristics of anterior prostate cancers (APCs) and to compare these with posterior prostate cancers (PPCs).

PATIENTS AND METHODS

We reviewed 1290 consecutive open and laparoscopic radical prostatectomies (RPs) at the authors' institution from January 2000 to March 2004. Prostates were processed using a whole-mount technique. Each surgical specimen was reviewed by one pathologist, and tumour areas were marked, measured and mapped. Positive surgical margins (PSMs) were defined as the presence of cancer cells at the inked surface of the specimen. Specimens were then categorized by the location of their dominant tumour, i.e. pure anterior, anterior > posterior, posterior > anterior, or pure posterior. We compared the clinical and pathological characteristics of 259 patients in the pure-anterior group with the 594 in the pure-posterior group.

RESULTS

Before RP, APCs had a significantly lower biopsy Gleason score (78% vs 68% with Gleason 4-6), fewer mean biopsy cores positive (2.0 vs 2.6), a smaller median percentage of positive cores (17% vs 26%), lower clinical stage (T1 in 79% vs 62%), and higher progression-free probability estimated by preoperative nomogram (86% vs 84%) than PPCs. Patients with APCs also had more previous negative biopsy sessions. The pathological analysis of RP specimens showed that those with APCs had higher tumour volume (1.6 vs 0.83 mL) and had a higher PSM rate (12% vs 7%) than those with PPCs, despite specimens with PPCs having higher rates of extraprostatic extension (10% vs 19%).

CONCLUSIONS

APCs have lower Gleason grade and lower rates of extraprostatic extension, yet patients with anterior tumours have higher overall tumour volumes and higher PSM rates. Because current tools for detecting and staging prostate cancer can underestimate the extent of anterior prostate disease, improved methods are needed for localizing and characterizing anterior cancers.

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 </= .02) to the nomograms in the overall study population. The contribution of MR findings was significant in all risk groups but was greatest in the intermediate- and high-risk groups (P < .01 for both). Accuracy in the prediction of OCPC with MR was higher when MR spectroscopic imaging was used, but the difference was not significant.

CONCLUSION

Endorectal MR imaging and combined endorectal MR imaging-MR spectroscopic imaging contribute significant incremental value to the staging nomograms in predicting OCPC.

Prognostic factors and reporting of prostate carcinoma in radical prostatectomy and pelvic lymphadenectomy specimens

This paper, based on the activity of the Morphology-Based Prognostic Factors Committee of the 2004 World Health Organization-sponsored International Consultation, describes various methods of handling radical prostatectomy specimens for both routine clinical use and research purposes. The correlation between radical prostatectomy findings and postoperative failure is discussed in detail. This includes issues relating to pelvic lymph node involvement, detected both at the time of frozen section and in permanent sections. Issues of seminal vesicle invasion, including its definition, routes of invasion and relationship to prognosis, are covered in detail. The definition, terminology and incidence of extra-prostatic extension are elucidated, along with its prognostic significance relating to location and extent. Margins of resection are covered in terms of their definition, the etiology, incidence and sites of positive margins, the use of frozen sections to assess the margins and the relationship between margin positivity and prognosis. Issues relating to grade within the radical prostatectomy specimen are covered in depth, including novel ways of reporting Gleason grade and the concept of tertiary Gleason patterns. Tumor volume, tumor location, vascular invasion and perineural invasion are the final variables discussed relating to the prognosis of radical prostatectomy specimens. The use of multivariate analysis to predict progression is discussed, together with proposed modifications to the TNM system. Finally, biomarkers to predict progression following radical prostatectomy are described, including DNA ploidy, microvessel density, Ki-67, neuroendocrine differentiation, p53, p21, p27, Bcl-2, Her-2/neu, E-cadherin, CD44, retinoblastoma proteins, apoptotic index, androgen receptor status, expression of prostate-specific antigen and prostatic-specific acid phosphatase and nuclear morphometry.

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).

Positive proximal (bladder neck) margin at radical prostatectomy confers greater risk of biochemical progression

OBJECTIVES

To identify the prognostic significance of positive bladder neck margin as the sole positive margin after radical retropubic prostatectomy for treatment of prostate cancer.

METHODS

We retrospectively analyzed the data from patients who underwent radical retropubic prostatectomy at Johns Hopkins Hospital between 1984 and 2001. Of 164 patients with positive margins, 38 had a positive margin only at the bladder neck margin and 126 had a positive margin at one or more locations separate from the bladder neck margin.

RESULTS

Kaplan-Meier analyses showed that patients with a positive bladder neck margin had a greater biochemical progression risk than patients with positive margins at one or more locations other than the bladder neck margin. The 5-year actuarial risk of progression in men with positive and negative bladder neck margins was 69.8% and 33.0%, respectively. A positive bladder neck margin was statistically an independently significant predictor of progression (P = 0.001), along with the prostatectomy Gleason score (P = 0.0001) in the multivariate analysis. The hazard ratio for predicting progression for postoperative Gleason score and bladder neck positivity was 2.1 and 2.5, respectively. Serum prostate-specific antigen values, clinical stage, age, and the percentage of tumor at the bladder neck margin were not predictors of progression in either univariate or multivariate analysis.

CONCLUSIONS

Patients with a positive bladder neck margin as the sole positive margin at radical retropubic prostatectomy have a greater risk of biochemical progression than patients with one or more positive margins at other locations, although not as adverse as the risk reported for those with Stage T4 disease.

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.