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In Reply: Re: Automated Prostate Volume Determination with Ultrasonographic Imaging
0022-5347/96/1553-1038$03.00/0
V O ~155. . 1038-1039. March 19% Printed I n U.S.A.
TliE JOURNAL. OF UROtOcY
Copyright 0 1996 by A ~ R I C A N UROIDCICAL ASSOCIATION, bc.
Letters to the Editor RE: RANDOMIZED DOUBLE-BLIND STUDY COMPARING THE EFFICACY OF TERAZOSIN VERSUS PLACEBO IN WOMEN WITH PROSTATISM-LIKE SYMPTOMS H. Lepor and C. Theune
J. Urol.. l&t:116-118, 1995 To the Editor. The authors note that while 50% of the unscreened geriatric men with symptoms of prostatism (or geriatric v o i l n g dysfunction) respond, only 17% of symptomatic geriatric women respond to a-blockers, which is the same percentage of women who respond to placebo. Therefore, they conclude t h a t a-blockers are ineffective in women. While stating t h a t there may be an unknown subset of female responders, the authors contend t h a t female and male nonresponders may have similar pathology, and t h a t they should be studied in the hope that some new medication might be beneficial. The accompanying editorial comment agreed about the need to study nonresponders. However, why not study responders as well? What is their pathophysiology? Also, how do a-blockers work? After extensive urodynamic evaluation, Gleason and Bottaccini found that terazosin may work by significantly increasing bladder capacity.' (Maybe this fact accounts for female incontinence while taking a-blockers.) Blaivas noted how little we know about symptoms, prostate obstruction and geriatric voiding dysfunction.* We must investigate symptomatic men and women with geriatric voiding dysfunction thoroughly, and determine which subsets respond to which medication and why. If a-blockers do indeed increase bladder capacity in certain populations, this could help identify subgroups of men and women amenable to appropriate therapy. Respectfully, Gerald Frankel Department of Urology Trinity Professional Plaza 4325 North Josey Lane Suite 301 Carrolton, Texas 75010
'ram hypertrophy, prostatitis or normal prostates.' Approximately 10 years ago, I calculated 5 parameters from prostatic sanograms by manually tracing the prostatic contours: prostatic volume, presumed circle area ratio, anteroposterior diametedtransverse ,diameter, asymmetry index and dissimilarity index. The weighted sum of prostatic volume, presumed circle area ratio, anteroposterior diameter/transverse diameter and asymmetry index was used to discriminate cancer and hypertrophy from prostatitis or normal prostates with an accuracy of 90%.The other value, subtracting weighted sum of prostatic volume and presumed circle area ratio from that of anteroposterior diametedtransverse diameter, asymmetry index and dissimilarity index, discriminated cancer from hypertrophy with an accuracy of 70%. With an apparatus that outlinesthe prostate automatically, calculation of these values needs no additional procedure. These values are worth being calculated and printed on a report with prostatic volume, although the accuracy is as yet insufficient for the automated diagnosis of prostatic diseases. Respectfully, Akira Kimura Department of Urology Branch Hospial Faculty of Medicine The Uniuersity of Tokyo 3-28-6 Mejirodai, Bunkyo-ku Tokyo Japan 1. Kimura, A., Nakamura, S., Niizuma, M., Hoshino, T., Niijima, T., Ohashi, Y.and Higuchi, T.: Quantitative analysis of ultrasonogram of the prostate. J. Clin. Ultrasound, 1 4 501, 1986.
Reply by Authors. These remarks about the 5 parameters calculated from prostatic sonograms may be important to distinguish benign from malignant prostates. The proposed parameters are numerical descriptions of the standard ultrasonographic examination of the prostate. The presumed circle area ratio and the anteroposte1. Gleason, D. M. and Bottaccini, M. R.: Effect of terazosin on urine nor diameter/transverse diameter reflect the amount of enlargement storage and voiding in the aging male with prostatism. Neur- of the transition zone. The asymmetry index reflects the difference in the symmetry of the left and right sides of the prostate, and the ourol. Urodynam., 1 3 1, 1994. 2. Blaivas, J. G.: Urinary symptoms and symptom scores. J. Urol., dissimilarity index stresses differences in contour shape of sequenpart 2,lM): 1714,1993. tial cross sections. The weighted sum of these parameters was then used to distinguish between benign and malignant prostates. Compared to normal clinical ultrasonographic investigation of the prostate, the method of Kimura does not use the differences in gray tones within the gland. These differences in gray tones are the RE: AUTOMATED PROSTATE VOLUME DETERMINATION leading guidelines for detection of malignant areas using ultrasound. WITH ULTRASONOGRAPHIC IMAGING Hypoechoic lesions and hyperechoic foci within a hypoechoic lesion R.G. Aarnink, A. L. Huynen, R. J. B. Giesen, J. J. M. C. H. de indicate an increased probability for neoplasm. On the other hand, la Rosette, F. M. J . Debruyne and H. Wijkstra transrectal ultrasound of the prostate has been considered operator dependent, and several studies indicate that the positive predictive J. Uroi., 153: 1549-1554, 1995 value of transrectal ultrasound is less than 10% in the case of To the Editor. I was greatly impressed by the fact that the authors negative digital rectal examination and a prostate specific antigen have been successful in outlining the prostate in the ultrasonic (PSA) level of less than 4 ngJm1.I We performed a study on the images automatically. Manual tracing of the prostatic contours has sensitivity and specificity of ultrasound in patients scheduled to been inevitable not only in the planimetric volume calculation but undergo radical prostatectomy. Of 12 patients transverse cross secalso in the ellipsoid volume calculation. In the prolate ellipse volume tions were recorded every 4 mm. and the resulting images were calculation, a n operator has had to input 6 points to measure the 3 interpreted by an experienced urologist. The results were then comdiameters. Among these volume calculation techniques, planimetry pared to the histopathology results of the removed specimens. A is the most accurate but it is extremely time-consuming. Therefore, sensitivity of 50% and specificity of 68% were found prospectively in automated volume determination using edge detection technique the transrectal ultrasound images, with poor sensitivity in ventral and planimetry will become routine. They state that the automated segments (12%).* Since Kimura uses the shape of the prostate contour instead of the method could not determine the prostate contours correctly in only 1 among 56 unselected patients because of poor image quality. This texture of internal structures to calculate the 5 parameters, the rate of miscalculation is small enough, even though it may increase method is only capable of detecting advanced prostate cancer leading to displaced contours which is also indicated by the fact that only 4 in a multicenter trial with urologists less experienced in ultrasound of the 51 patients with confirmed prostate cancer i n his study unas they stated. Making use of this system, I wish they would calculate the param. derwent radical prostatectomy, while the others had hormonal or eters that I previously reported to discriminate prostatic cancer radiation treatment (reference 1 in Letter). Prostate cancer, how1038
1039
LETTERS TO THE EDITOR ever, is best curable when detected at an early stage. Therefore, interest has been directed toward improvement of earlier diagnosis. Introduction of absolute PSA levels, PSA in proportion to the prostatic volume, predicted PSA levels, PSA velocity and age-related PSA levels all attempted to improve the early diagnosis of prostate cancer.’ Also, studies were begun to decrease the subjectivity of transrectal ultrasound of the prostate by using computerized interpretation of the texture of these images.2 Although the ideal test for prostate cancer has not been found yet, improvement in the early diagnosis of malignancy has been established. Despite the limitations for early cancer detection, we believe that quantitative analysis of the prostate shape can be useful for a more objective interpretation of prostatic ultrasound images. In combination with other tests, such as PSA, digital rectal examination and computerized interpretation of ultrasound texture of the internal structures, the early diagnosis may be improved.
1. Littrup, P. J., Kane, R. A,, Mettlin, C. J., Murphy, G. P., Lee, F., Toi, A., Badalament, R. and Babaian, R.: Cost-effective pros-
tate cancer detection. Reduction of low-yield bio sies Investigators of the American Cancer Society National bros&te Cancer Detection Project. Cancer, 7 4 3146, 1994. 2. Giesen, R. J. B., Huynen, A. L., Aarnink, R. G., de la Rosette, J. J. M. C. H., Kaa, C. v.d., Oosterhof, G. 0. N., Debruyne, F. M. J. and Wijkstra, H.: Computer analysis of transrectal ultrasound images of the prostate for the detection of carcinoma: a prospective study in radical prostatectomy specimens. J. Urol., 154: 1397,1995.
URETERAL CALCULI Volume 155, Number 1, page 40, Table 3, Row 3:
V O ~155. . 1038-1039. March 19% Printed I n U.S.A.
TliE JOURNAL. OF UROtOcY
Copyright 0 1996 by A ~ R I C A N UROIDCICAL ASSOCIATION, bc.
Letters to the Editor RE: RANDOMIZED DOUBLE-BLIND STUDY COMPARING THE EFFICACY OF TERAZOSIN VERSUS PLACEBO IN WOMEN WITH PROSTATISM-LIKE SYMPTOMS H. Lepor and C. Theune
J. Urol.. l&t:116-118, 1995 To the Editor. The authors note that while 50% of the unscreened geriatric men with symptoms of prostatism (or geriatric v o i l n g dysfunction) respond, only 17% of symptomatic geriatric women respond to a-blockers, which is the same percentage of women who respond to placebo. Therefore, they conclude t h a t a-blockers are ineffective in women. While stating t h a t there may be an unknown subset of female responders, the authors contend t h a t female and male nonresponders may have similar pathology, and t h a t they should be studied in the hope that some new medication might be beneficial. The accompanying editorial comment agreed about the need to study nonresponders. However, why not study responders as well? What is their pathophysiology? Also, how do a-blockers work? After extensive urodynamic evaluation, Gleason and Bottaccini found that terazosin may work by significantly increasing bladder capacity.' (Maybe this fact accounts for female incontinence while taking a-blockers.) Blaivas noted how little we know about symptoms, prostate obstruction and geriatric voiding dysfunction.* We must investigate symptomatic men and women with geriatric voiding dysfunction thoroughly, and determine which subsets respond to which medication and why. If a-blockers do indeed increase bladder capacity in certain populations, this could help identify subgroups of men and women amenable to appropriate therapy. Respectfully, Gerald Frankel Department of Urology Trinity Professional Plaza 4325 North Josey Lane Suite 301 Carrolton, Texas 75010
'ram hypertrophy, prostatitis or normal prostates.' Approximately 10 years ago, I calculated 5 parameters from prostatic sanograms by manually tracing the prostatic contours: prostatic volume, presumed circle area ratio, anteroposterior diametedtransverse ,diameter, asymmetry index and dissimilarity index. The weighted sum of prostatic volume, presumed circle area ratio, anteroposterior diameter/transverse diameter and asymmetry index was used to discriminate cancer and hypertrophy from prostatitis or normal prostates with an accuracy of 90%.The other value, subtracting weighted sum of prostatic volume and presumed circle area ratio from that of anteroposterior diametedtransverse diameter, asymmetry index and dissimilarity index, discriminated cancer from hypertrophy with an accuracy of 70%. With an apparatus that outlinesthe prostate automatically, calculation of these values needs no additional procedure. These values are worth being calculated and printed on a report with prostatic volume, although the accuracy is as yet insufficient for the automated diagnosis of prostatic diseases. Respectfully, Akira Kimura Department of Urology Branch Hospial Faculty of Medicine The Uniuersity of Tokyo 3-28-6 Mejirodai, Bunkyo-ku Tokyo Japan 1. Kimura, A., Nakamura, S., Niizuma, M., Hoshino, T., Niijima, T., Ohashi, Y.and Higuchi, T.: Quantitative analysis of ultrasonogram of the prostate. J. Clin. Ultrasound, 1 4 501, 1986.
Reply by Authors. These remarks about the 5 parameters calculated from prostatic sonograms may be important to distinguish benign from malignant prostates. The proposed parameters are numerical descriptions of the standard ultrasonographic examination of the prostate. The presumed circle area ratio and the anteroposte1. Gleason, D. M. and Bottaccini, M. R.: Effect of terazosin on urine nor diameter/transverse diameter reflect the amount of enlargement storage and voiding in the aging male with prostatism. Neur- of the transition zone. The asymmetry index reflects the difference in the symmetry of the left and right sides of the prostate, and the ourol. Urodynam., 1 3 1, 1994. 2. Blaivas, J. G.: Urinary symptoms and symptom scores. J. Urol., dissimilarity index stresses differences in contour shape of sequenpart 2,lM): 1714,1993. tial cross sections. The weighted sum of these parameters was then used to distinguish between benign and malignant prostates. Compared to normal clinical ultrasonographic investigation of the prostate, the method of Kimura does not use the differences in gray tones within the gland. These differences in gray tones are the RE: AUTOMATED PROSTATE VOLUME DETERMINATION leading guidelines for detection of malignant areas using ultrasound. WITH ULTRASONOGRAPHIC IMAGING Hypoechoic lesions and hyperechoic foci within a hypoechoic lesion R.G. Aarnink, A. L. Huynen, R. J. B. Giesen, J. J. M. C. H. de indicate an increased probability for neoplasm. On the other hand, la Rosette, F. M. J . Debruyne and H. Wijkstra transrectal ultrasound of the prostate has been considered operator dependent, and several studies indicate that the positive predictive J. Uroi., 153: 1549-1554, 1995 value of transrectal ultrasound is less than 10% in the case of To the Editor. I was greatly impressed by the fact that the authors negative digital rectal examination and a prostate specific antigen have been successful in outlining the prostate in the ultrasonic (PSA) level of less than 4 ngJm1.I We performed a study on the images automatically. Manual tracing of the prostatic contours has sensitivity and specificity of ultrasound in patients scheduled to been inevitable not only in the planimetric volume calculation but undergo radical prostatectomy. Of 12 patients transverse cross secalso in the ellipsoid volume calculation. In the prolate ellipse volume tions were recorded every 4 mm. and the resulting images were calculation, a n operator has had to input 6 points to measure the 3 interpreted by an experienced urologist. The results were then comdiameters. Among these volume calculation techniques, planimetry pared to the histopathology results of the removed specimens. A is the most accurate but it is extremely time-consuming. Therefore, sensitivity of 50% and specificity of 68% were found prospectively in automated volume determination using edge detection technique the transrectal ultrasound images, with poor sensitivity in ventral and planimetry will become routine. They state that the automated segments (12%).* Since Kimura uses the shape of the prostate contour instead of the method could not determine the prostate contours correctly in only 1 among 56 unselected patients because of poor image quality. This texture of internal structures to calculate the 5 parameters, the rate of miscalculation is small enough, even though it may increase method is only capable of detecting advanced prostate cancer leading to displaced contours which is also indicated by the fact that only 4 in a multicenter trial with urologists less experienced in ultrasound of the 51 patients with confirmed prostate cancer i n his study unas they stated. Making use of this system, I wish they would calculate the param. derwent radical prostatectomy, while the others had hormonal or eters that I previously reported to discriminate prostatic cancer radiation treatment (reference 1 in Letter). Prostate cancer, how1038
1039
LETTERS TO THE EDITOR ever, is best curable when detected at an early stage. Therefore, interest has been directed toward improvement of earlier diagnosis. Introduction of absolute PSA levels, PSA in proportion to the prostatic volume, predicted PSA levels, PSA velocity and age-related PSA levels all attempted to improve the early diagnosis of prostate cancer.’ Also, studies were begun to decrease the subjectivity of transrectal ultrasound of the prostate by using computerized interpretation of the texture of these images.2 Although the ideal test for prostate cancer has not been found yet, improvement in the early diagnosis of malignancy has been established. Despite the limitations for early cancer detection, we believe that quantitative analysis of the prostate shape can be useful for a more objective interpretation of prostatic ultrasound images. In combination with other tests, such as PSA, digital rectal examination and computerized interpretation of ultrasound texture of the internal structures, the early diagnosis may be improved.
1. Littrup, P. J., Kane, R. A,, Mettlin, C. J., Murphy, G. P., Lee, F., Toi, A., Badalament, R. and Babaian, R.: Cost-effective pros-
tate cancer detection. Reduction of low-yield bio sies Investigators of the American Cancer Society National bros&te Cancer Detection Project. Cancer, 7 4 3146, 1994. 2. Giesen, R. J. B., Huynen, A. L., Aarnink, R. G., de la Rosette, J. J. M. C. H., Kaa, C. v.d., Oosterhof, G. 0. N., Debruyne, F. M. J. and Wijkstra, H.: Computer analysis of transrectal ultrasound images of the prostate for the detection of carcinoma: a prospective study in radical prostatectomy specimens. J. Urol., 154: 1397,1995.
URETERAL CALCULI Volume 155, Number 1, page 40, Table 3, Row 3: