Prostate Volume Measurement by TRUS Using Heights Obtained by Transaxial and Midsagittal Scanning: Comparison with Specimen Volume Following Radical Prostatectomy

Objective

The purpose of this study was to determine, when measuring prostate volume by TRUS, whether height is more accurately determined by transaxial or midsagittal scanning.

Materials and Methods

Sixteen patients who between March 1995 and March 1998 underwent both preoperative TRUS and radical prostatectomy for prostate cancer were included in this study. Using prolate ellipse volume calculation (height × length × width × π/6), TRUS prostate volume was determined, and was compared with the measured volume of the specimen .

Results

Prostate volume measured by TRUS, regardless of whether height was determined transaxially or midsagittally, correlated closely with real specimen volume. When height was measured in one of these planes, a paired t test revealed no significant difference between TRUS prostate volume and real specimen volume (p = .411 and p = .740, respectively), nor were there significant differences between the findings of transaxial and midsagittal scanning (p = .570). A paired sample test, however, indicated that TRUS prostate volumes determined transaxially showed a higher correlation coefficient (0.833) and a lower standard deviation (9.04) than those determined midsagittally (0.714 and 11.48, respectively).

Conclusion

Prostate volume measured by TRUS closely correlates with real prostate volume. Furthermore, we suggest that when measuring prostate volume in this way, height is more accurately determined by transaxial than by midsagittal scanning.     

Classification of Focal Prostatic Lesions on Transrectal Ultrasound (TRUS) and the Accuracy of TRUS to Diagnose Prostate Cancer

Objective

To improve the diagnostic efficacy of transrectal ultrasound (TRUS)-guided targeted prostatic biopsies, we have suggested the use of a new scoring system for the prediction of malignancies regarding the characteristics of focal suspicious lesions as depicted on TRUS.

Materials and Methods

A total of 350 consecutive patients with or without prostate cancer who underwent targeted biopsies for 358 lesions were included in the study. The data obtained from participants were randomized into two groups; the training set (n = 240) and the test set (n = 118). The characteristics of focal suspicious lesions were evaluated for the training set and the correlation between TRUS findings and the presence of a malignancy was analyzed. Multiple logistic regression analysis was used to identify variables capable of predicting prostatic cancer. A scoring system that used a 5-point scale for better malignancy prediction was determined from the training set. Positive predictive values for malignancy prediction and the diagnostic accuracy of the scored components with the use of receiver operating characteristic curve analysis were evaluated by test set analyses.

Results

Subsequent multiple logistic regression analysis determined that shape, margin irregularity, and vascularity were factors significantly and independently associated with the presence of a malignancy. Based on the use of the scoring system for malignancy prediction derived from the significant TRUS findings and the interactions of characteristics, a positive predictive value of 80% was achieved for a score of 4 when applied to the test set. The area under the receiver operating characteristic curve (AUC) for the overall lesion score was 0.81.

Conclusion

We have demonstrated that a scoring system for malignancy prediction developed for the characteristics of focal suspicious lesions as depicted on TRUS can help predict the outcome of TRUS-guided biopsies.     

Granulomatous prostatitis: A hypoechoic lesion of the prostate

Numerous benign and malignant entities can disrupt the normal prostatic parenchymal architecture producing hypoechoic lesions in the peripheral zone. We report two cases of granulomatous prostatitis mimicking carcinoma. The differential diagnosis of hypoechoic lesions and the etiologies of granulomatous prostatitis are discussed. All hypoechoic lesions in the peripheral zones of the prostate require biopsy for histologic diagnosis.     

MRS鉴别外周带前列腺炎与前列腺癌的初步研究

目的 探讨磁共振波谱(MRS)在外周带前列腺炎与前列腺癌中的鉴别诊断价值.方法 回顾性分析25例外周带前列腺炎及25例前列腺癌患者的MRI及MRS资料,计算T2WI低信号区(胆碱+肌酸)/枸橼酸盐(CC/C)比值,比较前列腺炎与前列腺癌CC/C比值差异;同时以对侧正常区的波谱曲线作为参照标准,比较前列腺炎与前列腺癌波谱曲线的异同.结果 前列腺癌CC/C比值为3.0±2.48,前列腺炎CC/C比值为5.2±7.08,两者间差异无统计学意义(P =0.306).前列腺炎与前列腺癌MRS曲线均表现为枸橼酸盐(Cit)峰明显下降,但前列腺癌胆碱(Cho)峰明显升高,而前列腺炎Cho峰无明显变化.结论 CC/C比值在鉴别外周带前列腺炎与前列腺癌中的价值不大,而Cho峰的变化具有重要价值,Cho峰越高,前列腺癌可能性越大.     

磁敏感成像技术与磁共振动态增强扫描对前列腺癌和前列腺炎鉴别诊断价值的对比分析

目的 探讨病变内磁敏感性效应(SusE)与磁共振动态增强扫描(DCE-MRI)定量参数在外周带前列腺癌和前列腺炎鉴别诊断中的价值.方法 回顾性分析65例行3.0 TMR磁敏感成像(SwI)和DCE扫描并经穿刺活检病理证实的前列腺外周带T2信号减低的初诊患者,其中前列腺癌32例,前列腺炎33例.以4分制评估外周带T2低信号灶及邻近外周带SusE,并测量相应层面病灶区及正常前列腺外周带DCE-MRI定量参数转运常数(Ktrans)、血管外细胞外间隙体积百分数(Ve)及速率常数(Kep).通过Spearman分析比较SusE与Ktrans、Kep、Ve的相关性.通过Mann-Whitney test检验比较前列腺癌和前列腺炎病灶SusE差异.单因素方差分析比较Ktrans、Ke.、Ve在前列腺癌、前列腺炎和正常前列腺外周带间的差异.ROC曲线比较SWI和DCE的诊断准确性.结果 SusE与Ktra、Kep呈正线性相关(r值分别为0.419、0.219,P值分别为＜0.001、0.034),与Ve无相关性(r=0.088,P=0.402).在外周带前列腺癌和前列腺炎中SusE、Ktrans、Ke.差异均有统计学意义(P＜0.05),Ve差异无统计学意义(P＞0.05).以0分作为界值点,SusE鉴别前列腺癌和前列腺炎的敏感性、特异性、ROC曲线下面积分别为73.68％、65.62％、0.767;以0.103 min-1作为界值,Ktrans鉴别前列腺癌和前列腺炎的敏感性、特异性、ROC曲线下面积分别为78.12％、84.21％、0.753.以0.431 min-1作为界值,Ken鉴别前列腺癌和前列腺炎的敏感性、特异性、ROC曲线下面积分别为78.95％、59.38％、0.767.结论SWI半定量参数SusE与动态增强定量参数具有一定的相关性,可作为DCE-MRI的一种补充方法.病灶内微出血灶可以作为辅助鉴别诊断前列腺癌与前列腺炎的证据.     

Diffusion-Weighted Imaging of a Prostate Cancer Xenograft Model Seen on a 7 Tesla Animal MR Scanner: Comparison of ADC Values and Pathologic Findings

Objective

To assess the relationship between apparent diffusion coefficient (ADC) values on diffusion-weighted magnetic resonance (MR) imaging and pathologic measures of a tumor using a prostate cancer xenograft model.

Materials and Methods

Eighteen athymic nude mice with 36 PC-3-induced tumors were sacrificed to obtain specimens immediately after MR imaging in order to compare the findings on MR images with those seen on pathological specimens. Using a high-field small-animal MR scanner, T1- and T2-weighted imaging and DW MR imaging was performed. Tumors were then processed for Hematoxylin and Eosin staining to evaluate tumor cellularity, intratumoral necrosis and immunostaining using antibodies directed against CD31 and vascular endothelial growth factor (VEGF) to determine the levels of microvessel density (MVD). Mean ADC values that were measured on the solid portion within each tumor were compared with tumor volume, cellularity, degree of necrosis, VEGF expression, and MVD in the corresponding section of the pathological specimen.

Results

Mean ADC values of the solid portion within the PC-3-induced high-grade tumors were significantly correlated with the degree of intratumoral necrosis (r = 0.63, p < 0.0001) and MVD (r = -0.44, p = 0.008) on pathologic slides. The ADC values were not significantly correlated with tumor cellularity, VEGF expression, or tumor volume in high-grade prostate cancer tissues.

Conclusion

In the xenografted prostate cancer model, the ADC values of the solid portion of the tumors are significantly correlated with tumor necrosis and MVD of the pathologic specimens. The ADC values may be utilized as surrogate markers for the noninvasive assessment of tumor necrosis and MVD in high-grade prostate cancer.     

前列腺横纹肌肉瘤的影像学表现分析(附3例报道并文献复习)

目的 探讨前列腺横纹肌肉瘤的影像学表现.资料与方法 回顾性分析3例前列腺横纹肌肉瘤患者的临床及影像学资料并作文献复习.结果 3例表现为前列腺明显增大,伴软组织肿块形成,CT和MR增强后均有明显强化,肿瘤内部有不规则坏死区.DSA造影可见新生肿瘤血管和明显的肿瘤染色征.对盆腔邻近组织、结构仅1例主要表现为膀胱受压,其余均表现为不同程度侵犯,膀胱和精囊腺是极易受侵犯的器官.1例发生肺和盆腔转移.结论 前列腺横纹肌肉瘤常见于青少年,CT和MR能显示前列腺肉瘤的表现以及对邻近结构的侵犯情况.     

Correlations between the various methods of estimating prostate volume: transabdominal, transrectal, and three-dimensional US.

OBJECTIVE: To evaluate the correlations between prostate volumes estimated by transabdominal, transrectal, and three-dimensional US and the factors affecting the differences. MATERIALS AND METHODS: The prostate volumes of 94 consecutive patients were measured by both transabdominal and transrectal US. Next, the prostate volumes of 58 other patients was measured by both transrectal and three-dimensional US. We evaluated the degree of correlation and mean difference in each comparison. We also analyzed possible factors affecting the differences, such as the experiences of examiners in transrectal US, bladder volume, and prostate volume. RESULTS: In the comparison of transabdominal and transrectal US methods, the mean difference was 8.4 +/- 10.5 mL and correlation coefficient (r) was 0.775 (p < 0.01). The experienced examiner for the transrectal US method had the highest correlation (r = 0.967) and the significantly smallest difference (5.4 +/- 3.9 mL) compared to the other examiners (the beginner and the trained; p < 0.05). Prostate volume measured by transrectal US showed a weak correlation with the difference (r = 0.360, p < 0.05). Bladder volume did not show significant correlation with the difference (r = -0.043, p > 0.05). The comparison between the transrectal and three-dimensional US methods revealed a mean difference of 3.7 +/- 3.4 mL and the correlation coefficient was 0.924 for the experienced examiner. Furthermore, no significant difference existed between examiners (p > 0.05). Prostate volume measured by transrectal US showed a positive correlation with the difference for the beginner only (r = 0.405, p < 0.05). CONCLUSION: In the prostate volume estimation by US, experience in transrectal US is important in the correlation with transabdominal US, but not with three-dimensional US. Also, less experienced examiners' assessment of the prostate volume can be affected by prostate volume itself.     

Imaging Findings of Castleman's Disease Localized in the Axilla: A Case Report

Castleman''s disease is a rare benign lymphoproliferative disorder of uncertain origin which most commonly involves the mediastinum but rarely affects the axilla. We report a case of localized Castleman''s disease involving the axillary lymph node. Mammography revealed a well-defined, homogeneously dense ovoid mass, 3 cm in size, in the left axilla, while gray-scale ultrasonography (US) demonstrated a well-defined, uniformly hypoechoic ovoid mass with good through transmission. Peripheral hypervascularity was observed at power Dopper US, and early rapid homogeneous enhancement at contrast-enhanced dynamic CT.     

TRUS, CT and MRI findings of hydatid disease of seminal vesicles

Hydatid disease of the urogenital system, especially seminal vesicles and prostate, or retroperitoneum is a very rare condition. Secondary dissemination of seminal vesicles has not been described before. We describe the transrectal ultrasonography (TRUS), CT and MRI findings of a secondary solitary hydatid cyst of the left seminal vesicle, in a patient with disseminated hydatid disease involving all abdominal organs except for right kidney. We obtained typical findings of hydatid cyst at all modalities. Received 13 June 1997; Revision received 23 September 1997; Accepted 14 November 1997     

Prostate biopsy after ano-rectal resection: value of CT-guided trans-gluteal biopsy

We describe our single-institutional experience with computed tomography (CT)-guided percutaneous transgluteal biopsy of the prostate in patients in whom transrectal ultrasound-guided biopsy is precluded by prior ano-rectal resection. Between March 1995 and April 2007, 22 patients had 34 prostate biopsies (mean age 68; mean PSA 29 ng/ml; mean follow-up 6.1 years). The charts of patients who had transgluteal biopsy were reviewed for demographic, complications and pathology. Ninety-five percent (21/22) of primary biopsies were diagnostic. Of the 21 diagnostic biopsies, 11 were positive for prostate cancer and ten were definitive benign samples. Seventy-three percent (8/11) of the patients had progressive PSA elevation that mandated 11 further prostate biopsies. Six patients had a second biopsy, one patient had a third and one patient had a fourth biopsy. Among patients who had serial biopsies, 38% (3/8) had prostate cancer. No complications or death occurred. A malignant biopsy was not significantly associated with core number (P = 0.58) or a high PSA level (P = 0.15). CT-guided transgluteal biopsy of the prostate is safe and effective.     

Fibroepithelial Polyp of the Bronchus: CT and Histopathologic Findings

A fibroepithelial polyp of the bronchus is a rare, benign, and endobronchial tumor, histologically consisting of fibrovascular stroma covered by normal respiratory epithelium. We report a case of a fibroepithelial polyp arising from the left main bronchus. On CT, a characteristic lobulating contour of the endobronchial nodule was well visualized, which histopathologically represented a typical papillary growth pattern of the nodule. Such a lobulating contour of the nodule might help make a correct diagnosis of this rare disease among other various endobronchial neoplasms.     

Granulomatous prostatitis: a pitfall in MR imaging of prostatic carcinoma

Granulomatous prostatitis is an uncommon disease that can prostatic carcinoma on both digital rectal examination and transrectal ultrasound. Four patients who underwent magnetic resonance imaging of the prostate had a histological diagnosis of graanulomatous prostatitis; three of them had recent urinary tract infections. The other patient had an associated midline prostatic cyst and a focus of malignancy. T1-and T2-weighted spin-echo images were obtained in all cases. Peripheral zone lesions of decreased signal intensity, suggestive of carcinoma,were found in all four patients on T2-weighted images. Granulomatous prostatitis should be considered in the differential diagnosis of low signal intensity areas with prostatic magnetic resonance imaging. Correspondence to; P.A. Gevenois     

Update on ultrasound elastography: Miscellanea. Prostate,testicle, musculo-skeletal

Nowadays ultrasound elastosonography is an established technique, although with limited clinical application, used to assess tissue stiffness, which is a parameter that in most cases is associated with malignancy.     

Fetal Musculoskeletal Malformations with a Poor Outcome: Ultrasonographic, Pathologic, and Radiographic Findings

The early and accurate antenatal diagnosis of fetal musculoskeletal malfomations with a poor outcome has important implications for the management of a pregnancy. Careful ultrasonographic examination of a fetus helps detect such anomalies, and a number of characteristic features may suggest possible differential diagnoses. During the last five years, we have encountered 39 cases of such anomalies, and the typical prenatal ultrasonographic and pathologic findings of a number of those are described in this article.     

Cystic Lung Disease: a Comparison of Cystic Size, as Seen on Expiratory and Inspiratory HRCT Scans

Objective

To determine the effects of respiration on the size of lung cysts by comparing inspiratory and expiratory high-resolution CT (HRCT) scans.

Materials and Methods

The authors evaluated the size of cystic lesions, as seen on paired inspiratory and expiratory HRCT scans, in 54 patients with Langerhans cell histiocytosis (n = 3), pulmonary lymphangiomyomatosis (n = 4), confluent centrilobular emphysema (n = 9), paraseptal emphysema and bullae (n = 16), cystic bronchiectasis (n = 13), and honeycombing (n = 9). Using paired inspiratory and expiratory HRCT scans obtained at the corresponding anatomic level, a total of 270 cystic lesions were selected simultaneously on the basis of five lesions per lung disease. Changes in lung cyst size observed during respiration were assessed by two radiologists. In a limited number of cases (n = 11), pathologic specimens were obtained by open lung biopsy or lobectomy.

Results

All cystic lesions in patients with Langerhans cell histiocytosis, lymphangiomyomatosis, cystic bronchiectasis, honeycombing, and confluent centrilobular emphysema became smaller on expiration, but in two cases of paraseptal emphysema and bullae there was no change.

Conclusion

In cases in which expiratory CT scans indicate that cysts have become smaller, cystic lesions may communicate with the airways. To determine whether, for cysts and cystic lesions, this connection does in fact exist, paired inspiratory and expiratory HRCT scans are necessary.     

Biexponential Apparent Diffusion Coefficients Values in the Prostate: Comparison among Normal Tissue,Prostate Cancer,Benign Prostatic Hyperplasia and Prostatitis

Objective

To investigate the biexponential apparent diffusion parameters of diverse prostate tissues and compare them with monoexponential apparent diffusion coefficient (ADC) value in the efficacy to discriminate prostate cancer from benign lesions.

Materials and Methods

Eleven healthy volunteers and 61 patients underwent a conventional (b-factors 0, 1000 s/mm²) and a 10 b-factor (0 to 3000 s/mm²) diffusion-weighted imaging (DWI). The monoexponential ADC value and biexponential parameters of fast ADC (ADCf), fraction of ADCf (f), slow ADC (ADCs) value for 29 prostate cancer, 28 benign prostatic hyperplasia (BPH), 24 prostatitis lesions and normal tissue were calculated and compared. Receiver operating characteristic analysis was performed to determine the sensitivity, specificity and optimal cut-off points.

Results

Prostate cancer had lower ADC, ADCf, f, and ADCs than all other tissues (p < 0.01). Prostatitis exhibited a lower ADC, ADCf, ADCs and f than the peripheral zone tissue (p < 0.01), and BPH showed a lower ADC and ADCf than the central gland tissue (p < 0.01). The ADCf demonstrated a comparable accuracy with ADC in differentiating cancer from BPH [area under the curve (AUC) 0.93 vs. 0.92] and prostatitis AUC 0.98 vs. 0.99) (both p > 0.05), but the AUC of f and ADCs in differentiating cancer from BPH (0.73 and 0.81) and prostatitis (0.88 and 0.91) were significantly lower than ADC (all p < 0.05).

Conclusion

The biexponential DWI appears to provide additional parameters for tissue characterization in prostate, and ADCf helps to yield comparable accuracy with ADC in differentiating cancer from benign lesions.     

Radiologic Findings of Renal Inflammatory Pseudotumor: A Case Report

Renal inflammatory pseudotumor is a very rare benign condition of unknown etiology characterized by proliferative myofibroblasts, fibroblasts, histiocytes, and plasma cells. In the case we report, the lesion appeared on contrast-enhanced power Doppler US images as a well-defined hypoechoic mass with intratumoral vascularity, and on CT as a low-attenuated mass. Differentiation from malignant renal neoplasms was not possible.