eMedicine Specialties > Urology > Benign Prostatic Hypertrophy
Transurethral Needle Ablation of the Prostate (TUNA): Treatment
Updated: Feb 7, 2008
Treatment
Surgical Therapy
Prior to starting the procedure, transrectal ultrasonography is performed to determine the length and width of the prostate. The periprostatic block can also be placed at this time. The length helps determine the number of lesions required to appropriately treat the gland. The width is used to determine the needle length.
Place interstitial radiofrequency (RF) needles through the urethra and into the prostatic lateral lobes to cause coagulation necrosis. Heat the tissue to approximately 110°C at an RF power of 456 kHz for approximately 3 minutes per coagulation defect, thereby creating the lesion. Specifically, the area of coagulation necrosis that is created is an ellipsoidal volume along the axis of the needle antenna.
RF energy is created and delivered to the active electrode by the RF generator. The electrode that delivers the RF energy and heats the tissue is the active electrode. It has a very small surface area, allowing the RF current to concentrate in the area immediately surrounding the small electrode.
Externally apply the indifferent electrode, which is large in size. This serves to collect the RF current delivered by the active electrode. No tissue heating occurs near this indifferent (second) electrode. Tissue heating occurs in the concentrated area surrounding the active electrode because this tissue resists the flow of RF current.
At further distances from the active electrode, the RF current rapidly decreases; thus, no further tissue heating occurs and a sphere of coagulation necrosis around the active electrode results.
The size of the lesion is related to the depth of the electrode, the size of the electrode, the power used, and the duration of treatment.
Use a 22F delivery catheter to deliver the RF via 2 needles at 40° angles to each other and at 90° angles to the catheter. The needles are located at the tip of the catheter and are advanced into the prostate by piercing the urethra.
Treat the prostate by moving the RF needle within the various prostatic zones, from the bladder neck to the verumontanum. The number of treatment planes is based on the length of the prostate. Perform approximately 1 plane per 1-1.5 cm of prostatic urethral length (ie, minimum of 2 treatment planes).
The prostatic urethra is preserved. Because the pain-sensitive region of the prostatic urothelium is preserved, general or spinal anesthesia is not needed. Urethra preservation is also thought to reduce postoperative complications of irritative voiding and hematuria.
The needles are covered by insulated sheaths, which allow for control of the length of the exposed needles. Thermosensors on the end of the catheter, in the needle sheaths, and in the rectum measure the temperature in the prostate and periprostatic areas. The shaft of the delivery catheter can be rotated 180°. The RF creates temperatures in the active electrode of 70-110°C, and treatment times are 3 minutes per lesion created.
In the early work on transurethral needle ablation (TUNA), Schulman performed pathologic examinations of the coagulation defect. This area of necrosis ranged from 1.2 cm by 0.7 cm to 1.7 cm by 1 cm.
Importantly, note that the high bladder neck probably should not be treated. Experience with this is very limited. Another drawback is that, with TUNA, no tissue is available for pathologic analysis.
Preoperative Details
Most patients are treated with oral sedation (Valium and Demerol) and urethral gel. Local anesthesia is placed with ultrasound or digital guidance. This typically is an outpatient procedure.
The patient needs to have sterile urine prior to performing TUNA. If this is not the case, he should be adequately treated with antibiotics.
Intraoperative Details
The procedure lasts approximately 30 minutes. The number of treatments is based on the length of the prostate. For lengths of less than 3 cm, use one treatment plane. For lengths of 3-4 cm, use 2 planes. For lengths greater than 4 cm, use 3 or more planes.
Postoperative Details
Postoperatively, the patient typically wears a catheter for 1-3 days. Postoperative urinary retention is reported in 13-41% of patients. Treatment is typically conservative (ie, catheter drainage), and this retention tends to resolve in less than 2 days in most patients. Secondary catheterization is reported in 12% of patients, and most patients are able to return to work in 2-3 days.
Postoperative antibiotic coverage is recommended for 3-5 days after TUNA or after the catheter is removed.
Follow-up
Determining the length of time necessary for the coagulation defect to mature is difficult. Pathologic studies performed at 1 month following TUNA continue to show areas of maturing fibrosis and necrosis. Naslund feels that patients may not see improvement in voiding symptoms for 2-6 weeks.1 Furthermore, the patient may continue to see improvement for up to 2-3 months postoperatively. Therefore, the therapy should not be considered a failure until after 2-3 months.
Some patients fail to resume voiding or fail to see significant improvement in symptoms following TUNA. These patients are typically treated with a formal TURP. Rosario et al reported that 22 out of 71 (31%) men treated with TUNA for symptomatic benign prostatic hypertrophy (BPH) proceeded to a TURP during a 1-year follow-up study.4 Kahn et al, Rodrigo Aliaga et al, Millard et al, and Zlotta et al report performing a TURP following initial treatment with TUNA in 2 of 45 patients (4%), 7 of 42 patients (14%), 5 of 20 patients (25%), and 8 of 38 patients (21%), respectively.5,6,7,8 Thus, a total of 44 patients out of 216 (20%) went on to undergo TURP. Long-term follow-up examinations over a period of months to years are needed to reevaluate symptom improvement.
For excellent patient education resources, visit eMedicine's Prostate Health Center. Also, see eMedicine's patient education article Enlarged Prostate.
Complications
Minimally invasive therapy is generally the next step after failed medical management, and it is the primary therapy for a patient who is not interested in medical therapy but is unwilling to undergo TURP. No mortality is reported, and morbidity is low.
Reported rates of urinary retention are 13-42%. Retention appears transient, lasting from 12-48 hours. Postoperative catheter usage alleviates this problem.
Urinary incontinence is not reported.
Macroscopic hematuria is noted in most patients for up to 24-48 hours. This is usually self-limiting and requires no treatment. Ensure that patients with coagulopathies have them corrected prior to transurethral needle ablation (TUNA).
Irritative voiding symptoms occur in up to 40% of the patients; however, these are typically self-limiting and resolve within 7 days. These complaints rarely last beyond 4 weeks.
A urinary tract infection and epididymitis are essentially nonexistent in the face of sterile urine preoperatively and appropriate antibiotic coverage postoperatively. Coverage is recommended for 3-5 days after TUNA or after the catheter is taken out.
Urethral strictures may occur from instrumentation of the urethra. Reported rates are less than 2%; however, reported rates with a standard TURP are as high as 7.3%.
Little evidence suggests that retrograde ejaculation occurs. Marginal decreases in ejaculatory fluid are reported. Reported rates after TURP are 50-95%.
The incidence of erectile dysfunction is rare, less than 2%.
Impotence is reported in approximately 3% of the patients, and deterioration in function is reported slightly more often. Improvement in erectile function is reported by 14-21% of men.
Postoperative hematology and electrolyte changes are not noted in these patients.
More on Transurethral Needle Ablation of the Prostate (TUNA) |
| Overview: Transurethral Needle Ablation of the Prostate (TUNA) |
| Workup: Transurethral Needle Ablation of the Prostate (TUNA) |
 Treatment: Transurethral Needle Ablation of the Prostate (TUNA) |
| Follow-up: Transurethral Needle Ablation of the Prostate (TUNA) |
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References
Naslund MJ, Stitcher MF. A cost comparison of TUNA vs TURP. J Urol. 1997;157 (supplement):155A.
Chapple CR, Issa MM, Woo H. Transurethral needle ablation (TUNA). A critical review of radiofrequency thermal therapy in the management of benign prostatic hyperplasia. Eur Urol. Feb 1999;35(2):119-28. [Medline].
Naslund MJ, Carlson AM, Williams MJ. A cost comparison of medical management and transurethral needle ablation for treatment of benign prostatic hyperplasia during a 5-year period. J Urol. Jun 2005;173(6):2090-3; discussion 2093. [Medline].
Rosario DJ, Woo H, Potts KL, Cutinha PE, Hastie KJ, Chapple CR. Safety and efficacy of transurethral needle ablation of the prostate for symptomatic outlet obstruction. Br J Urol. Oct 1997;80(4):579-86. [Medline].
Kahn SA, Alphonse P, Tewari A, Narayan P. An open study on the efficacy and safety of transurethral needle ablation of the prostate in treating symptomatic benign prostatic hyperplasia: the University of Florida experience. J Urol. Nov 1998;160(5):1695-700. [Medline].
Rodrígo Aliaga M, López Alcina E, Monserrat Monfort JJ, Pontones Moreno JL, Valls Blasco F, Boronat Tormo F, et al. [Treatment of benign hyperplasia of the prostate using thermal transurethral needle ablation (TUNA)]. Actas Urol Esp. Jul-Aug 1997;21(7):649-54. [Medline].
Millard RJ, Harewood LM, Tamaddon K. A study of the efficacy and safety of transurethral needle ablation (TUNA) treatment for benign prostatic hyperplasia. Neurourol Urodyn. 1996;15(6):619-28; discussion 628-9. [Medline].
Zlotta AR, Peny MO, Matos C, Schulman CC. Transurethral needle ablation of the prostate: clinical experience in patients in urinary acute retention. Br J Urol. Mar 1996;77(3):391-7. [Medline].
Schulman CC, Zlotta AR. Transurethral needle ablation of the prostate for treatment of benign prostatic hyperplasia: early clinical experience. Urology. Jan 1995;45(1):28-33. [Medline].
Hill B, Belville W, Bruskewitz R, Issa M, Perez-Marrero R, Roehrborn C, et al. Transurethral needle ablation versus transurethral resection of the prostate for the treatment of symptomatic benign prostatic hyperplasia: 5-year results of a prospective, randomized, multicenter clinical trial. J Urol. Jun 2004;171(6 Pt 1):2336-40. [Medline].
Beduschi MC, Oesterling JE. Transurethral needle ablation of the prostate: a minimally invasive treatment for symptomatic benign prostatic hyperplasia. Mayo Clin Proc. Jul 1998;73(7):696-701. [Medline].
Berry SJ, Coffey DS, Walsh PC, Ewing LL. The development of human benign prostatic hyperplasia with age. J Urol. Sep 1984;132(3):474-9. [Medline].
Bouza C, Lopez T, Magro A, Navalpotro L, Amate JM. Systematic review and meta-analysis of Transurethral Needle Ablation in symptomatic Benign Prostatic Hyperplasia. BMC Urol. 2006;6:14. [Medline].
Boyle P, Robertson C, Vaughan ED, Fitzpatrick JM. A meta-analysis of trials of transurethral needle ablation for treating symptomatic benign prostatic hyperplasia. BJU Int. Jul 2004;94(1):83-8. [Medline].
Bruskewitz R, Issa MM, Roehrborn CG, Naslund MJ, Perez-Marrero R, Shumaker BP, et al. A prospective, randomized 1-year clinical trial comparing transurethral needle ablation to transurethral resection of the prostate for the treatment of symptomatic benign prostatic hyperplasia. J Urol. May 1998;159(5):1588-93; discussion 1593-4. [Medline].
Guess HA, Arrighi HM, Metter EJ, Fozard JL. Cumulative prevalence of prostatism matches the autopsy prevalence of benign prostatic hyperplasia. Prostate. 1990;17(3):241-6. [Medline].
Lepor H. Natural History, Evaluation, and Nonsurgical Management of Benign Prostatic Hyperplasia. In: Walsh PC,Retik AB, Vaughan ED Jr, Wein AJ. Campbell's Urology. 7th ed. Philadelphia, Pa: WB Saunders; 1998:1453-60.
McConnell JD. Epidemiology, Etiology, Pathophysiology, and Diagnosis of Benign Prostatic Hyperplasia. In: Walsh PC, Retik AB, Vaughan ED Jr, Wein AJ. Campbell's Urology. 7th ed. Philadelphia, Pa: WB Saunders; 1998:1429-52.
McCullogh DL. Minimally Invasive Treatment of Benign Prostatic Hyperplasia. In: Walsh PC, Retik AB, Vaughan ED Jr, Wein AJ. Campbell's Urology. 7th ed. Philadelphia, Pa: WB Saunders; 1998:1503-5.
Mebust WK. Transurethral Surgery. In: Walsh PC, Retik AB, Vaughan ED Jr, Wein AJ. Campbell's Urology. 7th ed. Philadelphia, Pa: WB Saunders; 1998:1511-28.
Perlmutter AP. New Uses of Energy for the Treatment of BPH. AUA Update Series. 1997;XVI:250-5.
Roehrborn CG, Issa MM, Bruskewitz RC, Naslund MJ, Oesterling JE, Perez-Marrero R, et al. Transurethral needle ablation for benign prostatic hyperplasia: 12-month results of a prospective, multicenter U.S. study. Urology. Mar 1998;51(3):415-21. [Medline].
Schulman CC, Zlotta AR. Transurethral needle ablation (TUNA) of the prostate: clinical experience with two years follow-up in patients with benign prostatic hyperplasia (BPH). Eur Urol. 1996;30(Suppl 2):263.
Schulman CC, Zlotta AR, Rasor JS, Hourriez L, Noel JC, Edwards SD. Transurethral needle ablation (TUNA): safety, feasibility, and tolerance of a new office procedure for treatment of benign prostatic hyperplasia. Eur Urol. 1993;24(3):415-23. [Medline].
Keywords
transurethral needle ablation, transurethral needle ablation of the prostate, TUNA, transurethral destruction of prostate tissue by radiofrequency thermotherapy, TUMP, prostate cancer, prostate surgery, prostate-specific antigen, prostate specific antigen, PSA, prostate needle ablation, benign prostatic hypertrophy, benign prostatic hyperplasia, BPH, prostatism, American Urologic Association Symptom Score, AUA Symptom Score, International Prostate Symptom Score, IPSS, prostatic enlargement, enlarged prostate, digital rectal examination, DRE, interstitial radiofrequency needles, interstitial RF needles, heat-induced coagulation necrosis, transurethral resection of the prostate, TURP, TUNA of the prostate, diminished uroflow, urodynamic obstruction
