Implications of small, peripheral hypoechoic lesions in endorectal US of the prostate

The Role of Transrectal Ultrasound for Finding Focal Lesions in Prostate Cancer Detection Compared to Systematic Sextant Biopsy

OBJECTIVES

To evaluate the difference in cancer detection rate between targeted biopsy of focal lesions detected on transrectal ultrasound (TRUS) and systematic sextant biopsy.

MATERIALS AND METHODS

This retrospective study included patients who underwent TRUS-guided prostate biopsy between April 2014 and April 2017 and classified them into three groups: (1) sextant biopsy group patients underwent systematic sextant biopsy without evaluation of focal lesions on TRUS (n = 400), (2) focal lesion group patients underwent targeted biopsy for TRUS-detected lesions (n = 496), and (3) nonfocal lesion group patients had no TRUS-detected focal lesions (n = 222). Positive biopsy rates were compared using Chi-square tests between biopsy groups in all patients and two subgroups divided by prostate-specific antigen (PSA) level of 10 ng/mL.

RESULTS

The positive biopsy rate decreased in the order of the focal lesion group, the sextant biopsy group, and the nonfocal lesion group. All prostate cancers and prostate cancers with a Gleason score ≥7 were detected more frequently among patients with PSA ≤10 ng/mL in the focal lesion group than in the sextant biopsy group ( p = 0.008 and 0.007, respectively) and less frequently among patients with PSA >10 ng/mL in the nonfocal lesion group than in the sextant biopsy group ( p = 0.007 and 0.003, respectively).

CONCLUSION

In conclusion, searching focal lesion by TRUS is useful for improving the positive biopsy rate and risk stratification of PCa compared to systematic sextant biopsy without careful TRUS examination.

Prostate cancer detection rate according to lesion visibility using ultrasound and MRI

AIM

To evaluate the difference in prostate cancer detection rates according to lesion visibility using transrectal ultrasound (TRUS) and magnetic resonance imaging (MRI) before biopsy.

MATERIALS AND METHODS

Patients who underwent TRUS-guided prostate biopsy in 2016 and 2017 (n=1,022) were divided into three groups: (1) patients who did not undergo a prebiopsy MRI (group 1, n=622); (2) patients without visible lesions on the prebiopsy MRI (group 2, n=77); and (3) patients with visible lesions on the prebiopsy MRI (group 3, n=323). Biopsy results were compared using chi-square tests or independent t-tests between patients with and without TRUS-visible lesions in each group. A logistic regression test was used to determine the variables independently associated with the detection of clinically significant cancer.

RESULTS

Focal lesions were visible on TRUS in 710 patients. Clinically significant cancers were detected in 39.4% and 13.1% of patients with and without TRUS-visible lesions, respectively (p<0.001). The cancer detection rate was significantly higher in patients with TRUS-visible lesions in groups 1 and 3 (p<0.001). Within group 1, the Gleason scores, number of positive cores, and the cancer involvement ratios were significantly greater in patients with TRUS-visible lesions than in patients without TRUS-visible lesions. MRI- and TRUS visibility were positively associated with the detection of clinically significant prostate cancer (p=0.002 and p<0.001, respectively).

CONCLUSION

TRUS- and MRI-visible focal lesions in the prostate were significantly associated with the detection of clinically significant cancer.

Focal lesion at the midline of the prostate on transrectal ultrasonography: take it or leave it?

PURPOSE

The purpose of this study was to analyze the detection rate of prostate cancers from targeted biopsy specimens of midline focal lesions and to investigate the ultrasonographic findings to reduce unnecessary additional targeted biopsies.

METHODS

Ninety-eight men with midline focal lesions detected on transrectal ultrasonography were enrolled. Additional targeted biopsies for midline focal lesions were performed after 12-core random systematic biopsies. Correlations between the ultrasonographic characteristics of midline focal lesions and the pathologic results were analyzed.

RESULTS

Twenty of 98 targeted biopsy cores (20.4%) were positive for malignancy. In a univariate analysis, midline focal lesions without bulging contours (P=0.023), with involved margins (P=0.001), without hypoechoic perilesional rims (P=0.005), and with longer diameters (P=0.005) were statistically significant for cancer detection. In a multivariate analysis, involved margin (P=0.027), having longer diameter (P=0.011) or absence of hypoechoic perilesional rim (P=0.025) made a statistically significant contribution to cancer detection.

CONCLUSION

Biopsy of midline focal lesions was not always non-significant in the detection of prostate cancer. Additional targeted biopsies should be considered in cases of midline focal lesions with involved margins but without hypoechoic perilesional rims.

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.

Role of colour Doppler imaging in detecting prostate cancer

OBJECTIVE

This prospective study was undertaken to evaluate the role of colour Doppler sonography in the assessment of prostate carcinoma.

METHODS

Forty consecutive patients who were suspected of having prostate carcinoma with either raised prostate specific antigen or abnormal digital rectal examination were included in the study. Transrectal greyscale and colour Doppler sonography of the prostate was performed using a 5-9 MHz intracavitary probe. Needle biopsies were taken from areas that showed increased flow on colour Doppler. The results were correlated with the final diagnosis established on histopathological examination.

RESULTS

Comparison of greyscale and colour Doppler sonography showed that the latter is more sensitive and specific in predicting the malignancy. The statistical parameters of colour Doppler versus grayscale sonography were: sensitivity 88.23 vs. 73.52, specificity 66.66 vs. 33.33, positive predictive value 93.75 vs. 85.18, and negative predictive value 50 vs. 22.22, respectively.

CONCLUSION

Colour Doppler and greyscale sonography should be routinely performed to improve detection of prostate carcinoma and to target the lesion.

Transrectal ultrasound in detecting prostate cancer compared with serum total prostate-specific antigen levels

We carried out a retrospective study to review the efficiency of grey-scale transrectal ultrasonography (TRUS) in detecting prostate cancer compared with the data in recent published work, including alternative imaging methods of the prostate gland. Our study group consisted of 830 patients who underwent TRUS-guided biopsy of the prostate between May 2000 and June 2004. The relation between abnormal TRUS findings and serum total prostate-specific antigen (tPSA) levels was evaluated in patients with prostate cancer who were divided into three different groups according to serum tPSA levels. Group I included patients with tPSA levels of 4-9.9 ng/mL, group II included tPSA levels of 10-19.9 ng/mL and group III included patients with tPSA levels of 20 ng/mL or more. In general, TRUS detected 185 (64%) of 291 cancers with a specificity of 89%, a PPV of 76% and an accuracy of 80%. TRUS findings enabled the correct identification of 22 (56%) of the 39 cancers in group I, 28 (30%) of the 93 cancers in group II and 135 (85%) of the 159 cancers in group III. In conclusion, TRUS alone has a limited potential to identify prostate cancer, especially in patients with tPSA levels lower than 20 ng/mL. Therefore, increased numbers of systematically placed biopsy cores must be taken or alternative imaging methods are required to direct TRUS-guided biopsy for improving prostate cancer detection.

Relative contribution of digital rectal examination and transrectal ultrasonography in interpreting serum prostate-specific antigen values for screening prostate cancer in Arab men

BACKGROUND

This study was conducted to determine the utility of digital rectal examination (DRE), transrectal ultrasonography (TRUS) and serum prostate-specific antigen (PSA) in the diagnosis of prostate cancer in men in Arabia, an are of the world with a relatively low incidence of this disease.

PATIENTS AND METHODS

329 patients suspected of having prostate cancer on account of raised serum PSA level (>4 ng/ml), DRE or TRUS findings, underwent TRUS-guided prostate biopsy. Raised PSA individually as well as combined, or a lesion suspicious of carcinoma on DRE or TRUS was recorded as PSA(+), DRE(+) or TRUS(+), respectively. The contribution of DRE, TRUS and serum PSA to the diagnosis of prostate cancer was analysed.

RESULTS

Of the 329 patients who had prostate biopsies 109 cases (33.1%) had PCa. Of these 109 patients 56 (51%) had DRE(+), 77 (42%) had TRUS(+) and 49 (66%) had both DRE(+) and TRUS(+). Statistical analysis revealed that DRE(+) tripled the probability for cancer. PSA over a range of 10-50 ng/mL demonstrated an increasing cancer probability ranging from 2 to 3 fold. TRUS(+) was only significantly associated with cancer risk if PSA was elevated. The presence of all three factors increased the cancer probability by 6 to 7 fold.

CONCLUSION

TRUS findings are dependent on PSA for interpretation while DRE(+) with elevated PSA makes PCa more likely.

EUS for locoregional staging of prostate cancer--a pilot study

BACKGROUND

This was a pilot study on EUS for locoregional evaluation of prostate cancer.

OBJECTIVE

Our purpose was to evaluate radial and linear-array EUS in locoregional prostate cancer staging.

DESIGN, SETTING, PATIENTS

From April to December 2005, 23 patients were referred to the Department of Urology with a confirmed or highly suspected diagnosis of prostate cancer on the basis of cytohistologic examination of fragments obtained by transrectal US-guided biopsy or transuretheral means. After institutional review board approval, informed consent was obtained from all patients.

INTERVENTION

An endosonographer and a radiologist with expertise in prostate imaging performed radial and linear EUS examinations without knowledge of the stage of prostate cancer of the referred patients.

MAIN OUTCOME MEASUREMENTS

Systematic prostatic evaluation by EUS. All patients underwent prostatectomy, and the surgical specimens were analyzed and correlated with EUS findings.

RESULTS

Mean age was 65.91 years, and the mean prostate-specific antigen level was 27.73 ng/mL. Histopathologic study of the surgical specimen revealed adenocarcinoma in 20 of 23, atypical adenomatous hyperplasia in 2 of 23, and sclerosing adenosis in 1 of 23. Staging by EUS for T stage showed different sensitivity (S), specificity (E), and accuracy (A) according to the degree of tumor invasiveness as follows: T1 (S: 51.3%, E: 53.2%, A: 49.1%); T2 (S: 100%, E: 91.67%, A: 95%); T3 (S: 100%, E: 100%, A: 100%). In 3 (3/23) patients EUS did not find a defined lesion, but the surgical specimen showed T1 stage cancer. EUS staging for N stage showed 62.5% sensitivity, 58.33% specificity, and 60% accuracy for N0. Regarding N1, 58.3% sensitivity, 52.50% specificity, and 60% accuracy were found.

LIMITATIONS

Uncontrolled, nonrandomized study.

CONCLUSIONS

EUS presented high sensitivity, specificity, and accuracy for prostate cancer staging.

Transrectal ultrasound guided biopsy for detecting prostate cancer: can random biopsies be reduced using the 4-dimensional technique?

We present our experience with a new technique of real time 3-dimensional sonography -- "4-dimensional Transrectal ultrasound (TRUS)" guided prostate biopsy. A total of 64 patients suspected of having prostate cancer based on an elevated prostate-specific antigen (greater than 4 ng/ml) formed the study group. A voluson (General Electric Vivid 3) ultrasound machine equipped with a transrectal 5-8 MHz curvilinear transducer was used. Sonography-guided prostate biopsy was performed following prostate imaging and volume calculation using 3D and 4D imaging. Biopsies of tumor suspicious areas, if present, as well as random biopsies were done. Histopathology showed prostate cancer in 15 (23.4%) and benign prostatic conditions in 49 (76.6%). TRUS examination in the 15 detected prostatic cancers showed that 6(40%) were hypoechoic, 4 (26.7%) were of mixed hypo and hyper echogenicity, 1 (6.7%) was hyperechoic, and 4 (26.7%) were isoechoic. TRUS finding of a hypoechoic lesion was significantly associated with malignancy. Other TRUS findings such as texture, calcification, and cysts did not show any association with malignancy. Mortality was zero after ultrasound-guided prostate biopsy. TRUS is the diagnostic test of choice in detection of prostate cancer. With advances in the technique of TRUS, effort is being made to identify more subtle lesions in order to reduce random biopsies. 4-Dimensional TRUS does improve the diagnostic accuracy but there is still a group of patients with "invisible" cancers. Therefore, the policy of random biopsies has to be continued till this incidence can be eliminated.

Detection of clinical unilateral T3a prostate cancer ? by digital rectal examination or transrectal ultrasonography?

OBJECTIVE

To assess, in a retrospective study, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of digital rectal examination (DRE), transrectal ultrasonography (TRUS) and the combination of both in unilateral clinical T3a (cT3a) prostate cancer.

PATIENTS AND METHODS

The long-term outcome of surgical treatment for locally advanced prostate cancer is very good and surpasses that for radiotherapy outcomes, so it is anticipated that surgical management for cT3a disease will become more important, but staging methods for cT3a disease are not well studied. Between 1990 and 2004, 2240 patients had a radical prostatectomy at our institution; 267 were diagnosed as having clinical cT3a prostate cancer either by DRE or TRUS. The final histopathology was compared with the findings of DRE and TRUS. The sensitivity, specificity, PPV and NPV for DRE, TRUS and the combination of both were calculated.

RESULTS

The sensitivity, specificity, PPV and NPV by DRE only was 90.9%, 15.8%, 47.2% and 67.7%, by TRUS only was 80.2%, 25.3%, 47.1% and 60.7%, and by both DRE and TRUS was 71.1%, 41.1%, 50.0% and 63.2%. Although the sensitivity was lower in the combined group, it had the highest specificity (41.1%) and PPV (50.0%). The combination of DRE and TRUS can detect T3a prostate cancer more accurately than either method alone.

CONCLUSION

Until data on staging methods like magnetic resonance imaging become available, the combination of DRE and TRUS is advisable in selecting cT3a patients for primary radical prostatectomy.

O papel atual da ultra-sonografia transretal da próstata na detecção precoce do câncer prostático

OBJETIVO: Determinar o papel real que a ultra-sonografia da próstata, notadamente com a associação do Doppler colorido, desempenha no diagnóstico de lesões malignas na próstata. MATERIAIS E MÉTODOS: Foram estudados, prospectivamente, 84 pacientes submetidos a biópsia guiada por ultra-sonografia transretal. Em todos os pacientes foram feitos estudo com Doppler colorido, à procura de focos de hipervascularização, e o exame ultra-sonográfico habitual. Os resultados foram comparados com os diagnósticos histopatológicos obtidos. RESULTADOS: A ultra-sonografia transretal habitual (escala de cinza) apresentou sensibilidade de 67,7%, especificidade de 52,8%, valor preditivo positivo de 45,6% e valor preditivo negativo de 73,6%. A adição do estudo com Doppler colorido ocasionou aumento importante da especificidade (de 52,8% para 79,2%) e do valor preditivo positivo (de 45,6% para 62,0%), porém causou queda na sensibilidade (de 67,7% para 58,0%). Além disso, houve perda de 32,2% dos cânceres, que não foram diagnosticados por nenhum dos dois métodos, e esses pacientes, apesar de possuírem cânceres menos extensos, eram todos clinicamente significativos (Gleason 6 ou mais). CONCLUSÃO: Mesmo com a associação do Doppler colorido, a ultra-sonografia transretal não possui capacidade suficiente para definir, através dos seus achados, quais pacientes devem ou não realizar biópsia.

The value of contrast enhanced power Doppler ultrasonography in differentiating hypoehoic lesions in the peripheral zone of prostate

OBJECTIVE

To characterize the hypoechoic prostate nodules in the peripheral zone by means of power Doppler ultrasonography (PDUS) and contrast enhanced PDUS (CE-PDUS).

MATERIALS AND METHODS

Thirty-two patients with dijital rectal examination findings suspicious for malignancy and/or a serum PSA level higher than 4 ng/dl, and who had hypoechoic nodules on transrectal ultrasonography were enrolled in this prospective study. Power Doppler ultrasonography (PDUS) images before and after sonocontrast (Levovist) injection were photographed for further evaluation. All patients were also evaluated by a systematic and nodule targeted biopsy approach. The photographs were re-evaluated by two radiologists for the presence and type of vascularity. The type of vascularity was categorized as peripheral, central, mixed and penetrating. The latter two were accepted as representatives of malignancy. The results of PDUS and CE-PDUS were compared to each other and to the pathological results.

RESULTS

There was a high level of interobserver agreement (Kappa: 0.80-0.95). Nineteen patients, but only 14 nodules were malignant on pathological examination. Sensitivity, specificity positive and negative predictive values for PDUS were 57, 50, 47, and 60%, respectively. On CE-PDUS, the sensitivity increased (93%) in expense of specifity (17%). The positive and negative predictive values were 46 and 75%, respectively. There was no significant difference between PDUS and CE-PDUS.

CONCLUSION

This study revealed that both benign and malignant nodules might be hypervascular and show malignant type of vascularity on PDUS. Contrary to some recent reports, we can conclude that the CE-PDUS does not provide a considerable aid to the diagnosis of prostate carcinoma on morphological basis due to its very low specificity despite its relatively higher sensitivity.

Transrectal sonographic features of prostatic intraepithelial neoplasia: correlation with pathologic findings

PURPOSE

This study was conducted to evaluate the transrectal sonographic (TRUS) features of prostatic intraepithelial neoplasia (PIN) by comparing the histopathologic results with TRUS findings in patients who had undergone TRUS-guided prostate biopsy.

METHODS

From an initial set of 307 patients who underwent TRUS-guided prostate biopsy, TRUS findings for 44 patients whose pathologic results were consistent with PIN were reviewed retrospectively. Among these 44 patients, 12 had only PIN, 20 PIN associated with prostatitis, and 12 PIN associated with prostate cancer foci. After exclusion of the foci that included PIN associated with prostatitis and PIN associated with prostate cancer at the same site, the pathologic results for the core specimens from the 100 PIN foci were correlated with TRUS findings according to their location. The sonographic features sought were hypoechoic areas and regions of heterogeneous echogenicity.

RESULTS

Positive TRUS findings were detected in 43% of PIN and 36% of high-grade PIN (HGPIN) focise. For the HGPIN foci with positive TRUS findings, the detected sonographic features were clusters of millimetric hypoechoic foci (CMHF) (53%), hypoechoic areas with well-defined borders (27%), and heterogeneous echogenicity (20%) (not significant). The sensitivity of the presence of CMHF for the diagnosis of HGPIN was only 19%.

CONCLUSIONS

TRUS-detected CMHF may indicate HGPIN. Because of the limited sensitivity of this finding, TRUS detection of CMHF does not warrant biopsy, although these lesions warrant close monitoring.

Contemporary impact of transrectal ultrasound lesions for prostate cancer detection

PURPOSE

Transrectal ultrasound (TRUS) guided systematic biopsy of the prostate is the gold standard diagnostic modality for prostate cancer. Consequently, the value of discrete hypoechoic lesions on TRUS lesions considered suspicious for cancer deserves meticulous reevaluation, specifically in the prostate specific antigen era when the majority of tumors diagnosed are nonpalpable. We studied whether the predictability of a biopsy core changes if the tissue comes from an isoechoic vs hypoechoic lesion.

MATERIALS AND METHODS

Prospective data were collected on 3,912 consecutive patients referred to our medical center between 1993 and 1999 for biopsy of the prostate. A sextant technique (apex, mid gland and base) with an additional core biopsy from the transitional zone was used. If a hypoechoic lesion was identified, the biopsy was taken from the lesion. Correlation between hypoechoic lesions, isoechoic areas and cancer detection for each core was performed.

RESULTS

A total of 31,296 cores were obtained from the cohort. Overall 2,642 (68%) cores had at least 1 hypoechoic lesion ultrasonographically. Cancer was detected in 675 (25.5%) and 323 (25.4%) patients with or without hypoechoic lesions (p = 0.97). The per core cancer detection was fairly uniform and averaged 9.3% and 10.4% for hypoechoic and isoechoic areas, respectively. The difference was not statistically significant (p = 0.3). Gleason scores were less than 7, 7 and greater than 7 in 46%, 34% and 20% of cases, respectively.

CONCLUSIONS

Despite the higher prevalence of cancers discovered in prostates with hypoechoic areas, the hypoechoic lesion itself was not associated with increased cancer prevalence compared with biopsy cores from isoechoic areas. For impalpable tumors TRUS findings are not contributory for staging.

Color and power Doppler sonography in the diagnosis of prostate cancer: comparison between vascular density and total vascularity

OBJECTIVE

Advances in color flow Doppler (CFD) and power Doppler imaging (PDI) have potential for prostate cancer diagnosis. Previous reports based on qualitative assessment suggest that hypervascularity increases likelihood of prostate cancer. Our objective was to compare 2 methods of vascularity assessment using PDI: total vascularity (TV) and vascular density (VD). The goal was to determine whether quantitative Doppler vascularity correlates with the likelihood of prostate cancer. Quantitative measurements were compared with subjective visual analysis of images.

METHODS

Ninety patients before biopsy had gray scale sonography, CFD, and PDI. Histologic analysis showed adenocarcinoma, prostate intraepithelial neoplasia, benign prostatic hypertrophy/prostatitis, and benign findings. The CFD and PDI images were analyzed for vascularity by (1) integrating the number of blood vessels over an imaged area (TV) and (2) integrating the number of vessels over a unit area of tissue (VD). Images were also assessed visually. VD, TV, and visual assessment were compared with one another and histologic findings.

RESULTS

Mean volume was not different. In each pathologic group, vascularity extent measured by TV and VD ranged from low to high. Disease groups did not exhibit a substantial difference in vascularity by either quantitative or qualitative analyses. Regionally, central gland TV was not significantly more vascular than peripheral gland TV except in benign prostatic hypertrophy. However, peripheral gland VD was 2.5 times greater than central gland VD. Seventy-one percent of the 31 focal hypoechoic lesions were hypervascular. Only 23% were carcinoma.

CONCLUSIONS

Pathologic categories were not separable by apparent vascular measurement. All pathologic categories showed low, moderate, or high vascularity; thus vascular areas by themselves did not distinguish cancer types, nor did focal hypervascular hypoechoic areas increase the likelihood of cancer. These imaging techniques provided no further resolution of tumor discrimination over multiple biopsies of the prostate.

Contrast-enhanced transrectal ultrasonography of a novel canine prostate cancer model

OBJECTIVE

This study evaluated the utility of a new animal model for prostate cancer imaging using a new ultrasonographic contrast agent (Sonazoid [NC100100]; Amersham Health, Oslo, Norway), for prostate cancer detection.

METHODS

Twenty-four dogs had a canine transmissible venereal sarcoma cell line injected (50 million cells/mL) directly into the prostate, producing a neoplasm in 15 to 40 days. Transrectal ultrasonography was performed in power Doppler mode on 8 dogs (phase I) and in gray scale phase inversion harmonic imaging mode on 16 animals (including control animals without tumors; phase II). Evaluations were repeated after intravenous injections of the contrast agent (dose, 0.00625-0.20 microL/kg). Histopathologic examination was performed after each study. For the phase II experiments, sensitivity, specificity, and accuracy were calculated.

RESULTS

The contrast agent improved visualization of the prostate cancer vascularity and delineation of tumor size and shape in both power Doppler and phase inversion harmonic imaging modes. Canine transmissible venereal sarcoma tumors ranging from 3 x 5 to 40 x 50 mm were detected. The accuracy for detecting the number of prostate tumors increased (in phase II) from 67% to 87% with the addition of the contrast agent. Histopathologic examination confirmed the ultrasonographic findings and revealed typical canine transmissible venereal sarcoma cells infiltrating the prostate with moderate neovascularity.

CONCLUSIONS

The novel canine tumor model was useful for evaluating ultrasonographic prostate imaging techniques. Improved detection of prostate tumors in dogs was possible with gray scale phase inversion harmonic imaging of the contrast agent. The accuracy of lesion detection increased from 67% to 87%.

Should ultrasound criteria of the prostate be redefined to better evaluate when and where to biopsy

During the past 10 years, it has been suggested, and accepted by some, that transrectal ultrasound (TRUS) of the prostate should be used to identify a hypoechoic lesion or, if needed, guide biopsy into nonspecific areas. Retrospectively, the authors attempted to evaluate the need to identify areas that were on pathologic analysis, prostate cancer, but were not hypoechoic, but would require random/systematic biopsy to exclude prostate cancer. Six-hundred fifteen consecutive men were referred to the authors because of a concern found on digital rectal examination or because of increase in prostate-specific antigen. All patients underwent TRUS-guided biopsy of the prostate using either the four-quadrant or sextant biopsy technique. Each area undergoing biopsy was characterized as: 1) normal-appearing; 2) hypoechoic; 3) mixed echogenic (containing both hypoechoic and hyperechoic elements); 4) subtly hyperechoic (containing no calculi); or 5) isoechoic (lesion was seen because of distortion of the normal architecture). A diagnosis of carcinoma was made in 197 patients (32%). Of these, 99 (50.2%) patients had a hypoechoic lesion as the primary site, corresponding to their highest Gleason grade. Twenty-five (12.7%) had mixed echogenicity, nine (4.6%) had hyperechoic foci, and 23 (11.7%) had isoechoic biopsy-proven foci of prostate cancer. Forty-one (20.8%) patients with adenocarcinoma had normal ultrasound findings. The median Gleason grade for cancer in visible mixed echogenic and hyperechoic areas were generally higher than that for cancer in hypoechoic sites. Hypoechoic cancer sites had a Gleason grade range of 2 to 10 (median 5); mixed echogenic foci had a Gleason range of 2 to 10 (median 6); hyperechogenic cancers had a Gleason range of 2 to 8 (median 6); isoechoic cancers had a Gleason range of 2 to 7 (median 5); normal foci had a Gleason range of 2 to 8 (median 5). Results of this study suggest that 50% of clinically significant prostate cancers are not purely hypoechoic, and 37% of all diagnosed cancers contain no hypoechoic elements.

Transrectal ultrasound and biopsy in the early diagnosis of prostate cancer

BACKGROUND

Historically, the prostate was evaluated for cancer by simple digital rectal examination, and biopsy to obtain a tissue diagnosis of cancer was performed blindly. The advent of ultrasound technology offered a new way to evaluate the prostate, and biopsy techniques were soon developed to incorporate ultrasound guidance.

METHODS

The authors review the role of transrectal ultrasound (TRUS) of the prostate and ultrasound-guided biopsy of the prostate in the diagnosis of prostate cancer. These techniques are traced from their origins to the current standards of care, with attention paid to developments and controversies in recent literature.

RESULTS

Early experience with TRUS led to the description of "classic" sonographic findings of prostate cancer. To obtain a tissue diagnosis of cancer, these regions were initially targeted in ultrasound-guided biopsies. Concomitant with the development of TRUS, though, was the development of the prostate-specific antigen (PSA) assay. Over the past decade, there has been a profound stage migration due to earlier detection of prostate cancer. Most patients now diagnosed with prostate cancer have no palpable abnormality or specific sonographic findings. In response, ultrasound-guided biopsies have become more systematic, rather than lesion-specific, in nature.

CONCLUSIONS

TRUS continues to play an important role in the evaluation of the prostate when malignancy is suspected. Although the optimal method of prostate biopsy is controversial, ultrasound is critical in ensuring accurate sampling of the gland.

Correlations among prostatic biopsy results, transrectal ultrasound findings and PSA levels in diagnosing prostate adenocarcinoma

OBJECTIVE

The objective of this study was to evaluate transrectal ultrasound (TRUS) findings and prostate-specific antigen (PSA) levels in relation to prostatic biopsy results and to analyze their individual and combined performances in diagnosing prostate adenocarcinoma (PAC).

METHODS

Men (n=143) with PSA levels above 4 ng/ml underwent TRUS and randomized ultrasound-guided prostatic biopsy through the peripheral zone, including additional hypoechoic nodules biopsies, if they were noted on TRUS. Data related to TRUS, biopsy, and PSA level results were then correlated.

RESULTS

A significant correlation between TRUS images suspicious for PAC and a biopsy-confirmed diagnosis of PAC, or between the lack of such images and a negative biopsy result, was not found. However, a significant correlation was found between positive biopsy results and PSA levels greater or equal to 10 ng/ml. The sensitivity of transrectal ultrasound in making a diagnosis of PAC was 63%, whereas its specificity was 73%.

CONCLUSION

We conclude that while the separate performances of these examinations were not effective in diagnosing PAC, the integrated use of these methods was more adequate for making the diagnosis.

Contrast-enhanced three-dimensional power Doppler angiography of the human prostate: correlation with biopsy outcome

OBJECTIVES

To determine the feasibility of contrast-enhanced three-dimensional (3D) imaging of the prostatic vasculature using power Doppler imaging and to analyze whether semiquantitative judgments of 3D images with respect to symmetry and distribution of vascular structures correlated with biopsy outcome.

METHODS

3D power Doppler images were obtained before and after intravenous administration of 2.5 g Levovist. Subsequently, random and/or directed transrectal ultrasound (TRUS)-guided biopsies were performed. Vascular images were analyzed by two experts. Prostate vasculature was judged with respect to symmetry and vessel distribution using a (scale) grading system.

RESULTS

Eighteen patients with a suspicion of prostate cancer either because of an elevated prostate-specific antigen (greater than 4.0 ng/mL; Tandem-R-assay) or an abnormal digital rectal examination were included in the study. Prostate cancer was detected in 13 patients. Vascular anatomy was judged abnormal in unenhanced images in 6 cases, of which 5 proved malignant. Enhanced images were considered suspicious for malignancy in 12 cases, including 1 benign and 11 malignant biopsy results. Sensitivity of enhanced images was 85% (specificity 80%) compared with 38% for unenhanced images (specificity 80%) and 77% for conventional gray-scale TRUS (specificity 60%). Of 6 patients who showed no B-mode abnormalities, vascular patterns were judged abnormal in 4 cases, of which 3 were malignant.

CONCLUSIONS

Contrast-enhanced 3D power Doppler angiography is feasible in patients with suspicion of prostate cancer who are scheduled for prostate biopsies. The sensitivity of power Doppler 3D imaging for the detection of prostate malignancy increased from 38% (5 of 13) to 85% (11 of 13) after administration of intravascular microbubble contrast (Levovist), and specificity was found to be 80% (4 of 5) for both imaging modalities. Thus, the use of Levovist when combined with the power Doppler display mode and 3D image reconstruction offers a promising new research area that might prove useful in prostate cancer detection in the future.

Prostatic cancer: role of color Doppler imaging in transrectal sonography

OBJECTIVE

The aim of this study was to assess the roles of transrectal color Doppler and gray-scale sonography in revealing prostatic cancer, using biopsy as the reference standard.

SUBJECTS AND METHODS

Two hundred fifty-six patients referred for urologic studies underwent transrectal sonography using gray-scale and color Doppler scanning. All abnormal areas shown on gray-scale or color Doppler sonography or both were targeted and biopsies were performed. The patients also underwent random sextant biopsies. All biopsies were individually correlated with histopathologic findings and all results were analyzed.

RESULTS

Cancer was found on biopsy in 100 patients (39%), and equivocal sonographic results or prostatic intraepithelial neoplasia was found in 22 other patients (9%). In 16 of the patients in whom cancer was detected, the tumors were correctly revealed only with color Doppler sonography. These 16 patients had a mean Gleason score of 6.4 (range, 5-8). Biopsy findings in these 16 patients showed eight patients with extensive lesions, three with moderate lesions, and five with minimal lesions. However, in nine other patients with cancer (9% of cancers detected), both gray-scale and color Doppler sonography failed to reveal lesions that were found on sextant biopsy. An analysis showed that, although highly sensitive, color Doppler sonography was somewhat less specific than gray-scale sonography.

CONCLUSION

Color Doppler sonography should become a routine part of transrectal sonography of the prostate gland to improve detection and targeting of lesions. The practice of performing random sextant biopsies should also continue.

Prostate imaging may not be necessary in nonpalpable carcinoma of the prostate

OBJECTIVES

Stage T1c carcinoma of the prostate is defined as a nonpalpable carcinoma (NPC-P) that is not visible by imaging and is identified by needle biopsy performed because of elevated prostate-specific antigen (PSA) concentrations. The purpose of this study was to define the incidence of normal findings on transrectal ultrasound (TRUS) and/or endorectal coil magnetic resonance imaging (EMRI) among patients with NPC-P, as well as to investigate the value of differentiating patients with Stage T1c disease from all other patients with NPC-P.

METHODS

The records of 2211 patients diagnosed with prostate carcinoma between 1988 and 1995 were reviewed to identify 291 men with NPC-P. TRUS and EMRI reports were analyzed with regard to the presence and laterality of hypoechoic nodules or low-signal areas reported on T2-weighted images, respectively. Ninety percent of patients (n = 262) had at least six prostate biopsies, 185 patients (64%) underwent both TRUS and EMRI, 224 (77%) had TRUS, and 251 (86%) had an EMRI study.

RESULTS

Results were considered normal in 101 (47%) of 214 patients undergoing TRUS, in 58 (23%) of 249 undergoing EMRI, and in 22 (12%) of 185 undergoing both TRUS and EMRI. For the side of the prostate with positive biopsy results, correlation with imaging abnormalities was better for EMRI than for TRUS (39% versus 24%). There was no significant difference in mean PSA value, distribution of Gleason score, or unilateral versus bilateral positive biopsy results among patients with normal versus abnormal findings on both TRUS and EMRI.

CONCLUSIONS

(1) Only 12% of men with NPC-P have no TRUS or EMRI abnormalities, fulfilling the criteria for Stage T1c prostate carcinoma. (2) Those patients with Stage T1c disease do not differ from patients with NPC-P up-staged by TRUS or EMRI, with regard to pretreatment PSA levels, Gleason scores, and the probability of having bilateral rather than unilateral positive biopsy results. (3) The value of classifying patients with NPC-P into Stage T1c versus higher stages of prostate carcinoma on the basis of imaging should be questioned.

Transrectal ultrasound microbubble contrast angiography of the prostate

BACKGROUND

Prostate cancer, suspected by serum prostate-specific antigen (PSA) elevation and/or digital abnormalities, is not always evident on gray-scale or color Doppler transrectal ultrasound (TRUS). EchoGen (Sonus Pharmaceuticals, Inc., Bothell, WA), a blood vessel image enhancer able to visualize smaller, low-flow vessels and thus possibly the microvascular angiogenesis often associated with cancer, was employed to see if it would improve prostate cancer detection, particularly in patients with a rising serum PSA and prior negative biopsies.

METHODS

Color Doppler TRUS was performed before and after intravenous injection of 0.05 ml/kg of EchoGen. Random and/or specifically directed sextant TRUS biopsies were performed.

RESULTS

Fifteen patients with serum PSA elevations were included in the study. Fourteen had a negative prior biopsy (1-3 x). Prostate cancer was detected in 5 patients. Microvascular patterns were judged abnormal in 8 patients, 2 of which proved malignant, 2 of which were benign, and 1 of which was diagnosed with prostatis. False-negative results were observed in 3 patients, whose positive biopsy sites were from the prostate apex.

CONCLUSIONS

Following EchoGen administration, prostate blood vessel image enhancement was noted in all patients, and there were no adverse reactions during or after EchoGen administration with the dose employed.

Transrectal ultrasound-guided biopsy of the prostate: what you see is not what you get

A prospective trial involving 282 patients, beginning in December 1993, was undertaken to assess the correlation between our sonographic impression of prostatic malignancy and the histological findings of a random six quadrant biopsy in addition to histology of any sonographically evident focal peripheral zone (PZ) abnormality. The sonographic criteria used to suggest malignancy were: (i) presence of hypo-echoic PZ nodule; (ii) inhomogeneity of PZ; and (iii) loss of zonal architecture (ZA). The sonographic appearance was graded as either definitely benign, indeterminate, or definitely malignant. These impressions were then compared with the histology results. Eighty-two patients had histologically proven malignancy. Ultrasound showed the correct extent and site of malignancy in 42 patients. A further 26 patients had the extent of their malignancy either over- or under-estimated or had the malignancy placed in an incorrect site. Fourteen patients with histologically proven carcinoma had sonographically normal PZs. These findings highlight the shortcomings of ultrasound as a diagnostic tool in prostate cancer and show that six quadrant random biopsy of the prostate is far superior to unifocal biopsy of sonographically evident masses in the detection of prostate cancer.

Usefulness of aspiration cytology in prostate cancer detection

Aspiration cytology and core needle biopsy were performed in 79 patients who were suspected of having prostate cancer. Aspiration cytology and TURP were done in 77 cases not suspected of the disease. In the former group, they were both positive in 13 cases, aspiration cytology was negative and core needle biopsy positive in 4, and the reverse in 3 cases in whom cancer was confirmed by repeat core biopsy. All of the latter group were judged by aspiration cytology as being benign. Three cancers were detected by TURP. Aspiration cytology is a recommendable method in subjects with suspected prostate cancer.

The diagnostic value of colour Doppler flow in the peripheral zone of the prostate, with histological correlation

OBJECTIVE

To study the discriminative value of the amount of colour flow on Doppler ultrasound within the peripheral zone of the prostate.

PATIENTS AND METHODS

One-hundred and twenty three men were studied using a 7 MHz transrectal probe, and 274 guided biopsies were undertaken. With each biopsy histological outcome was correlated with the grade of colour flow on ultrasound hard copy images. Biopsies with inflammatory cell infiltration, but without carcinoma, were subgraded according to the degree of inflammatory cell infiltration; and these grades were correlated with the corresponding colour flow grade.

RESULTS

Normal colour flow was seen with both normal and abnormal prostate biopsy. With increased colour flow the likelihood of abnormal tissue increases; the highest grade of colour flow was seen with either carcinoma or prostatitis (grade 0, 1, 2 and 3 colour flow = 23%, 65%, 74% and 100% respectively of biopsies that were abnormal). In biopsies with inflammatory cell infiltration there was no linear relationship between the grades of colour flow and cellular infiltration (r = 0.52, P > or = 0.05, Kendall rank correlation). The mean grade of cellular infiltration was significantly greater in samples with grade 3 colour flow compared with grades 0-2.

CONCLUSION

Grading of the amount of colour flow with Doppler ultrasound is of limited diagnostic discrimination, although with the greatest colour flow specificity for the diagnosis of abnormal prostate (either cancer or prostatitis) is very high. With prostatitis, markedly increased colour flow reflects the severity of inflammatory cellular reaction.

A comparison between digitally-guided fine needle aspiration and ultrasound-guided transperineal core needle biopsy of the prostate for the detection of prostate cancer

OBJECTIVE

To prospectively examine the accuracy of fine needle aspiration (FNA) for the detection of prostate cancer. Ultrasound-guided core needle biopsy of the prostate was used as the standard to which the FNA results were compared.

PATIENTS AND METHODS

One-hundred patients who had been referred for urological evaluation were suspected of having prostate cancer on the basis of digital rectal examination (DRE) and/or transrectal ultrasound (TRUS). All were further evaluated by digitally guided transrectal FNA and by TRUS-guided transperineal core needle biopsy.

RESULTS

Prostate cancer was identified in 54 patients by core needle biopsy and in 45 by FNA. The sensitivity of FNA was 81% and both specificity and positive predictive value were 98%.

CONCLUSION

FNA is easily performed, has negligible morbidity and offers prompt results. These data suggest that FNA is a reasonable initial diagnostic procedure for the detection of prostate cancer. Core needle biopsy may be reserved for patients with negative cytology who are clinically suspected of having prostate cancer. In selected patients, FNA may be used as an alternative to core needle biopsy for diagnosis, treatment planning and follow-up.

Screening for carcinoma of the prostate: a GP based study

OBJECTIVE

To examine the feasibility and acceptability of screening for cancer of the prostate by digital rectal examination (DRE), prostate specific antigen (PSA) determination and subsequent transrectal ultrasound (TRUS) in selected patients in a single general practice in Hertfordshire.

SUBJECTS AND METHODS

A total of 568 of 856 men aged 55 to 70 accepted an invitation for a health check which included screening for prostate cancer. Of these, 80 individuals with either a raised PSA level or an abnormal DRE underwent TRUS. In 29 individuals biopsies were taken, 11 of which confirmed the presence of adenocarcinoma of the prostate giving an overall detected prevalence of 2%. Of the 11 tumours identified by screening, two were T1M0, four were T2M0, two were T3M0 and three were T3M1.

RESULTS

To assess the acceptability of the screening exercise a postal questionnaire was sent to all 568 participants: 83% replied and 69% reported no concern. Of the 67 individuals who had undergone TRUS, 69% reported discomfort. A total of 448 (95%) of respondents declared that they would be prepared to undergo the screening exercise again.

CONCLUSION

Screening for prostate cancer would seem to be technically feasible and generally acceptable. However, there is a considerable false positive rate in the PSA range 4 ng/ml to 10 ng/ml, particularly among men with clinical evidence of benign prostatic hyperplasia. To establish the true benefit of screening a large-scale prospective controlled study will be necessary.

The clinical utility of transrectal ultrasound and digital rectal examination in the diagnosis of prostate cancer

The development of high definition transrectal ultrasound probes has led to an increased interest in the ability of transrectal ultrasound of the prostate (TRUS) to assist in the diagnosis and management of prostate cancer. The present study was designed to examine the correlation of TRUS with digital rectal examination (DRE). The study group comprised 471 patients in whom the results of (a) DRE, (b) TRUS, and (c) histology of tissue obtained by transrectal biopsy of the prostate (TB), were all available. In those patients where both TRUS and DRE were negative, but prostate specific antigen (PSA) was greater than 10 micrograms ml-1, six random biopsies were performed. In all other cases the biopsies were TRUS directed to the suspicious lesion. There were 142 cases in whom both DRE and TRUS were negative or only mildly suspicious of malignancy. TB in these cases was positive for cancer in 17 cases (12%). In a further 126 cases, TRUS was positive for cancer, while DRE demonstrated no suspicious nodule. TB was positive in only 17 of these cases (13.5%). Similarly, in the 31 cases in which DRE was positive but TRUS was negative, TB was positive in only three cases (10%). In the 172 cases in whom both DRE and TRUS were positive, 99 biopsies were positive (57.5%). It was concluded from this study that DRE remains the most valuable single examination in the diagnosis of prostate cancer. TRUS increases the sensitivity of DRE if both are positive. When there is a discrepancy between the two examinations, the biopsy yield is low. When both are positive, a high cancer yield is obtained, TRUS having added value in directing the biopsy needle to the suspicious site. TRUS is thus a valuable adjunct to DRE in the diagnosis of prostate cancer.

Value of transrectal prostate ultrasonography pre-transurethral prostatectomy in screening for occult prostate carcinoma

A total of 311 patients who underwent consecutive transurethral resection of prostate (TURP) for obstructive voiding symptoms were reviewed. All patients had benign prostate glands by digital rectal examination. Results of preoperative ultrasound screening of the prostate in 65 of 311 patients showed 41 with nonmalignant prostate, but pathologic examination showed cancer in 11 and benign hyperplasia in 30. Of seven ultrasounds interpreted as suspicious for cancer, pathologic examination revealed benign hyperplasia in all seven. Of 17 patients with ultrasound interpretations consistent with prostate cancer, 14 had transrectal ultrasound-guided prostate biopsies prior to TURP. Biopsy specimens revealed benign hyperplasia without carcinoma in all 14 patients. Two of 17 patients refused biopsies, and 1 underwent TURP without biopsy for urinary retention and did have cancer. Sensitivity of prostate ultrasound in evaluation of occult prostate carcinoma in this group of patients was 8.3 percent and specificity was 56.6 percent. Our results indicate that transrectal prostate ultrasound performed on men with obstructive voiding symptoms and benign glands as evidenced by digital rectal palpation has little value in predicting the presence or absence of occult prostate cancer.

Transrectal ultrasound screening for prostatic adenocarcinoma with histopathological correlation. Factors affecting specificity

BACKGROUND

Ultrasound (US) is increasingly used for the detection of prostatic cancer, yet its specificity is low when used alone. A study was undertaken to examine the factors affecting the specificity of prostatic US.

METHODS

Thirty-five intact prostates obtained at autopsy were studied in vitro by US, and the findings were correlated with those in histologic sections.

RESULTS

US abnormalities were noted in 24 cases, but prostatic adenocarcinoma was diagnosed by US in only 5 of 12 proven cases. It appears that the US diagnosis of tumor is determined more by location than by size. Anterior and central tumors often are missed by US. Benign prostatic hyperplasia, which affects the transition zone, contributed to a false-positive or false-negative diagnosis of tumor in 10 of 35 cases. Other findings associated with abnormal US include abscesses, infarcts, and seminal vesicles embedded in the prostate.

CONCLUSION

The specificity of prostatic US is low; it should not be used as an isolated test in screening the prostate for tumors.

Predicted prostate specific antigen results using transrectal ultrasound gland volume. Differentiation of benign prostatic hyperplasia and prostate cancer

METHODS

The diagnostic performance of transrectal ultrasound (TRUS) gland volume and prostate specific antigen (PSA) results were evaluated in 204 men consecutively scheduled to undergo transurethral prostatic resection (TUR).

RESULTS

Nonpalpable prostate cancer was detected by TRUS alone in 18% (29 of 161) and by TUR alone in 9% (14/161), for an overall cancer incidence of 27%. A predicted PSA value (TRUS gland volume x 0.20 ng/ml/g = polyclonal PSA) was used for comparison with serum PSA for each patient. TRUS positive predictive value improved from 52% to 86% when serum PSA exceeded the predicted value. The specificity and positive predictive value of PSA at 2.5 ng/ml were 23% and 37%, respectively, which increased to 88% and 72%, respectively, when serum PSA exceeded the predicted value.

CONCLUSIONS

Predicted PSA values produce decision levels near the 95th percentile for each patient and assist individual biopsy decisions better than grouped gland volume ranges. Wider application of TRUS and PSA in any clinical setting or early detection program is now possible.

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.

Applications of prostate ultrasonography

Transrectal ultrasonography of the prostate is a relatively new diagnostic modality being used with increasing frequency in the assessment of prostatic disease. Applications include tumour staging, assisted biopsy and assessment of prostate size. The role of this study for the early detection of carcinoma of the prostate remains controversial and its role in this regard remains to be determined.

Screening for prostatic carcinoma

Routine testing for prostatic carcinoma by digital rectal examination, transrectal ultrasonography and prostate specific antigen determination has been proposed to reduce deaths by earlier diagnosis. The questionable reliability of results, cost of screening, and inability to establish a balance between the benefits of treatment and the adverse effects on the quality of life of the men screened make screening experimental until controlled studies prove its value.

Applications of prostate ultrasonography

Transrectal ultrasonography is a relatively new imaging modality that may be useful in the evaluation and management of patients with prostate cancer. Although cancer may have a characteristic appearance, it cannot always be reliably differentiated from benign conditions. While this technique has clinical applications in staging, monitoring tumor response to therapy, and assisting in biopsy, it is unclear as to whether useful information is obtained in the evaluation of patients with palpable disease. The role of transrectal ultrasonography in patients with nonpalpable disease or as a screening tool has yet to be determined. Other diagnostic tests in conjunction with ultrasound may in the future prove to be useful. Carefully performed prospective investigations with state-of-the-art equipment are still needed to further define the role of this diagnostic modality.

The significance of the prostatic hypoechoic area: results in 226 ultrasonically guided prostatic biopsies

A total of 666 patients with symptoms of urinary outflow obstruction underwent assessment of the patients 64 had a palpable abnormality suggestive of cancer (stages T1 to T4, or B to C). In the remainder the prostate was either palpably normal, firm or enlarged by benign prostatic hypertrophy. All 64 patients with a palpable abnormality and 162 of 602 with normal rectal examination findings had a hypoechoic area on transrectal ultrasound. Biopsy of the ultrasonic abnormality was done in 148 men by the transperineal route with linear array ultrasound guidance and in 78 by the transrectal route with a mechanical sector scanner in the sagittal plane. Of the 64 patients with a nodular prostate 34 (53%) had cancer (31% of those with stages T1 and 2, 83% with stage T3 and 100% with stage T4 disease). In 14% of the patients with stages T1 and T2 cancer the biopsy showed prostatic intraepithelial neoplasia grade 3. Of the 162 patients with a palpably normal prostate who underwent ultrasound-guided biopsy 11 (6.7%) had cancer and 6 (3.7%) had grade 3 prostatic intraepithelial neoplasia detected in the biopsy material. Patients with stages T1 to T2 cancer and those with ultrasound-diagnosed impalpable cancer were not significantly different with respect to patient age (67 versus 70 years), cancer size (3.0 +/- 1.6 versus 3.9 +/- 2.5 cm.2) or Gleason score (5.4 +/- 1.2 versus 6.5 +/- 0.9). The results demonstrate that ultrasound guidance improves the yield of prostate needle biopsy. Furthermore, it is suggested that prostate cancer found by ultrasound alone is not different from early palpable disease and should be treated in the same manner.

Fine needle aspiration biopsy of the prostate gland: our experience concerning 101 cases with histological follow-up

Our experience concerning 605 fine needle aspiration (FNA) biopsies performed between 1985 and 1988 is reported. FNA specimens of the prostate gland were compared to histological material in 101 cases: 37 patients underwent suprapubic prostatectomy, 15 radical prostatectomy, 28 transurethral resection, and 21 core needle biopsies. Adenocarcinoma was correctly diagnosed by using cytology in 39 out of 40 cases; benign prostatic hypertrophy was confirmed by histology in 54 out of 57 cytologically benign cases. The absolute sensitivity of the FNA biopsy was 98.2%; specificity was 98.1%; efficiency was 96%; and false negative rate was 6.6%. Our data support the value of transrectal aspiration biopsy as a precise and easy method for diagnosing prostatic cancer; the low false negative rate and the high number of correct diagnoses underline the great accuracy of the method.

Evaluation of transrectal ultrasound in the early detection of prostate cancer

To determine the ability of transrectal ultrasound to detect early localized prostate cancer, unsuspected (nonpalpable) cancer in the contralateral lobe of patients undergoing radical prostatectomy for clinically localized disease was evaluated. A total of 59 patients with palpable prostate cancer clinically confined to 1 lobe underwent transrectal ultrasound before radical prostatectomy and step-sectioning of the radical prostatectomy specimen. Transrectal ultrasound was performed with 5 or 7 MHz. real-time transrectal units. Pathological findings in these 59 cases revealed no tumor in the contralateral lobe in 34 (58%) and the presence of unsuspected tumor in 25 (42%). Transrectal ultrasound detected 13 of 25 unsuspected cancers for a sensitivity of 52%. Of 34 patients with no contralateral lobe lesion transrectal ultrasound was correct in 23 for a specificity of 68%. The positive and negative predictive values for transrectal ultrasound in this study group were 54 and 66%, respectively. There was no significant difference in the pathological size of the clinically suspected and clinically unsuspected cancers as measured by average largest dimension, and transrectal ultrasound sensitivity did not correlate with the size of the cancer. Based on careful sonopathological analysis, transrectal ultrasound may not be a good method to detect clinically unsuspected prostate cancer and the false positive rate would appear to be high.