MALIGNANT PROSTATE SURGERY I PERINEAL
The radical perineal prostatectomy was ﬁrst described as a surgical cure for prostate cancer in 1905. Its popularity waned in the late 1970s as the importance of the pelvic lymph node dissection for accurate staging was elucidated. More recently, there has been renewed interest in this anatomic approach to prostate cancer as more accurate staging methods have reduced the need for staging lymph node dissection. In addition, similar to its advantages in benign prostate surgery (see Plate 4-16), the perineal approach for prostate cancer treatment offers unmatched visualization of the apical prostate and urethral dissection, is important for cancer cure, and is associated with less blood loss. Unlike with the retropubic approach, a full bowel preparation is given the day before perineal surgery. After the induction of anesthesia, the patient is placed in an exaggerated lithotomy position; severe hip ankylosis or unstable prosthetic hips may thus be a contraindication to this approach. A curved Lowsley retractor is placed transurethrally into the bladder and its wings opened. A curvilinear incision is made around the anus as described for the perineal prostatectomy for benign prostatic hyperplasia (BPH; see Plate 4-16). After bluntly developing the ischiorectal fossa on each side, the central tendon is cut and the longitudinal muscle ﬁbers of the rectum identiﬁed. With gentle traction on the rectum, dissection is carried superiorly until the rectourethralis muscle, which connects the rectum to the perineal body, is identiﬁed. The rectourethralis muscle is divided close to the prostatic apex, allowing the rectum to fall dorsally. The risk of rectal injury is highest at this point. Ideally, this dissection is between the leaves of Denon-villiers fascia. With pressure on the Lowsley retractor, the prostate is delivered into the ﬁeld, allowing blunt, digital dissection of the prostate until its base is identiﬁed at the vesicoprostatic junction.
Unlike with perineal prostatectomy for BPH, the prostatic capsule is not incised when the entire gland is to be removed. Instead, the exposed anterior layer of Denon villiers fascia is incised vertically in the midline from the base to the apex of the prostate to preserve the neurovascular bundles. Careful lateral dissection and gentle traction help to preserve the neurovascular bundles as they course between the leaves of Denonvilliers fascia. At the prostatic apex, the bundles are also dissected free of the urethra, and the posterior urethra is incised sharply over the Lowsley retractor. With traction on the retractor, the anterior urethra is then transected and the prostate freed to the bladder neck by sharp and blunt dissection. The puboprostatic ligaments are then transected. Care is needed to avoid injuring the dorsal venous complex during this dissection of the anterior prostate.
The prostate bladder neck junction is identiﬁed by palpation of the wings of the Lowsley retractor. With sharp and blunt dissection, the bladder neck is preserved. The bladder neck is ﬁrst incised anteriorly to avoid injury to the ureteral oriﬁces posteriorly. With traction on the prostate, the bladder neck incision is continued circumferentially around the prostate base, dissecting and ligating the lateral pedicles coursing toward the prostate. Ligation of these pedicles is performed close to the prostate to avoid injury to the adjacent neurovascular bundles. With further posterior dissection, the paired vasa deferentia are ligated and transected and the seminal vesicles are excised with the prostate.
After the specimen is removed, the bladder neck is easily visible. Occasionally, it may be necessary to reconstruct the bladder neck in a “tennis racket” fashion with absorbable suture. Accurate anastomotic suture placement between the bladder neck and membranous urethra is guided by better visualization of these structures with the perineal method compared to the retro- pubic approach. A Penrose drain is placed near the bladder neck anastomosis and brought out through the skin incision. The levatorani muscles and central tendon are then reapproximated, and the skin closed with interrupted vertical mattress sutures. Patients are advised to ambulate the evening of surgery, and the drain is removed and patients are advanced to a regular diet the day after surgery. Rectal stimulation and medications are prohibited. Hospital discharge is on day 1 or 2 after surgery. Unique but infrequent complications of the perineal prostatectomy are transient lower extremity sensory neurapraxia (2%), and rectal incontinence (3%). Rates of urinary incontinence and erectile dysfunction are comparable to those of retropubic methods.