- Email: [email protected]
Prostatic Needle Biopsy: A Simple Technique for Increasing Accuracy
0022-534 7 /89/1424-1023$02.00/0 THE JOURNAL OF UROLOG'!
Vol. 14?,, October
Copyright© 1989 by AMERICAN UROLOGICAL ASSOCIATION, INC.
Printed in U.S.A.
PROSTATIC NEEDLE BIOPSY: A SIMPLE TECHNIQUE FOR INCREASING ACCURACY SUMNER MARSHALL* From the Department of Urology, University of California School of Medicine, San Francisco, California
Prostatic needle biopsies have a critical role in the management of suspicious prostatic irregularities. It is imperative that satisfactory cores of tissue for diagnosis be available for histological examination. The Bioptyt gun, with its spring trigger mechanism, has increased our ability to obtain consistently good cores of tissue relatively painlessly without adjunctive anesthesia in an office setting. Usually, the procedure is done transrectally, permitting direct palpation of the nodule in question. Transrectal ultrasonographic guidance in conjunction with digital palpation of the lesion might increase the accuracy of site localization. However, since the ultrasonic characteristics of carcinoma and benign disease overlap, depending on ultrasonography alone to find an underlying carcinoma has resulted in many conflicting results (that is the suspicious lesion on ultrasonography proves to be benign). The yield of true positive biopsy results (that is underlying carcinoma in a palpable nodule) is much higher when a definite nodule is palpable. 1 When ultrasonographic equipment is unavailable or logistically inconvenient, or the surgeon would prefer to avoid its use care must be taken to maximize the chances for accurate localization of the biopsy needle on the suspicious lesion. Generally, the surgeon "double-gloves", passing the biopsy needle along the index finger inside the outer glove and placing the needle at the site of sampling. Unfortunately, this technique may result not only in inadvertent scraping of the rectal mucosa but also in periodic scraping or perforation of the surgeon's finger, as has been my experience and that of 1 of my colleagues. To minimize these occurrences we now use a portion of the plastic sheath that protects the needle in its packaging as a guide to place the needle transrectally to the point of the desired biopsy. This sheath is cut to a size equal to the length of the
Plastic sheath
Trigger B\opty gun in cocked position with protective sheath in place. When gun 1s fired needle shoots forward to procure core of tissue.
Biopty gun to the end of the needle in the cocked position (see figure). When the gun is fired the end of the needle shoots forward beyond the end of the sheath to obtain the specimen. With this approach, which we have used in approximately 50 cases, we have not encountered any injury to the rectal mucosa or the surgeon's finger. We keep a supply of these sheaths cut to the proper length readily available in a sterile state. Double-gloving is not as necessary with this technique, although its use certainly will lessen the chance of fecal contamination of the prostate. For further assurance of accurate placement we hold the needle firmly in place, enclosed in the protective sheath, with its tip on the suspected area while the nurse releases the locking mechanism and activates the trigger. These modifications have proved most helpful to assure that the biopsy samples are taken from the suspicious areas and to decrease the risk to the rectum and surgeon's finger. REFERENCE
Accepted for publication April 21, 1989. *Requests for reprints: Department of Urology, U-518, University of California, San Francisco, California 94143-0738. t C. R. Bard, Covington, Georgia.
1023
1. Resnick, M. I.: Transrectal ultrasound guided versus digitally di-
rected prostatic biopsy: a comparative study. J. Urol., 139: 754, 1988.
Vol. 14?,, October
Copyright© 1989 by AMERICAN UROLOGICAL ASSOCIATION, INC.
Printed in U.S.A.
PROSTATIC NEEDLE BIOPSY: A SIMPLE TECHNIQUE FOR INCREASING ACCURACY SUMNER MARSHALL* From the Department of Urology, University of California School of Medicine, San Francisco, California
Prostatic needle biopsies have a critical role in the management of suspicious prostatic irregularities. It is imperative that satisfactory cores of tissue for diagnosis be available for histological examination. The Bioptyt gun, with its spring trigger mechanism, has increased our ability to obtain consistently good cores of tissue relatively painlessly without adjunctive anesthesia in an office setting. Usually, the procedure is done transrectally, permitting direct palpation of the nodule in question. Transrectal ultrasonographic guidance in conjunction with digital palpation of the lesion might increase the accuracy of site localization. However, since the ultrasonic characteristics of carcinoma and benign disease overlap, depending on ultrasonography alone to find an underlying carcinoma has resulted in many conflicting results (that is the suspicious lesion on ultrasonography proves to be benign). The yield of true positive biopsy results (that is underlying carcinoma in a palpable nodule) is much higher when a definite nodule is palpable. 1 When ultrasonographic equipment is unavailable or logistically inconvenient, or the surgeon would prefer to avoid its use care must be taken to maximize the chances for accurate localization of the biopsy needle on the suspicious lesion. Generally, the surgeon "double-gloves", passing the biopsy needle along the index finger inside the outer glove and placing the needle at the site of sampling. Unfortunately, this technique may result not only in inadvertent scraping of the rectal mucosa but also in periodic scraping or perforation of the surgeon's finger, as has been my experience and that of 1 of my colleagues. To minimize these occurrences we now use a portion of the plastic sheath that protects the needle in its packaging as a guide to place the needle transrectally to the point of the desired biopsy. This sheath is cut to a size equal to the length of the
Plastic sheath
Trigger B\opty gun in cocked position with protective sheath in place. When gun 1s fired needle shoots forward to procure core of tissue.
Biopty gun to the end of the needle in the cocked position (see figure). When the gun is fired the end of the needle shoots forward beyond the end of the sheath to obtain the specimen. With this approach, which we have used in approximately 50 cases, we have not encountered any injury to the rectal mucosa or the surgeon's finger. We keep a supply of these sheaths cut to the proper length readily available in a sterile state. Double-gloving is not as necessary with this technique, although its use certainly will lessen the chance of fecal contamination of the prostate. For further assurance of accurate placement we hold the needle firmly in place, enclosed in the protective sheath, with its tip on the suspected area while the nurse releases the locking mechanism and activates the trigger. These modifications have proved most helpful to assure that the biopsy samples are taken from the suspicious areas and to decrease the risk to the rectum and surgeon's finger. REFERENCE
Accepted for publication April 21, 1989. *Requests for reprints: Department of Urology, U-518, University of California, San Francisco, California 94143-0738. t C. R. Bard, Covington, Georgia.
1023
1. Resnick, M. I.: Transrectal ultrasound guided versus digitally di-
rected prostatic biopsy: a comparative study. J. Urol., 139: 754, 1988.