Steenkamp: Internal Urethrotomy Versus Dilation for Male Urethral Stricture
The Steenkamp trial was a single-center randomized comparison of optical internal urethrotomy (104 men) and filiform dilation (106 men) as outpatient treatment under local anesthesia for male urethral stricture. Recurrence-free survival did not differ significantly between the two procedures, and the hazard of recurrence rose by a factor of 1.22 for each centimeter of stricture length (95% CI 1.05 to 1.43).[1]
- Design and population
- Single-center randomized comparison of two outpatient endoscopic treatments. 210 men with proven urethral stricture treated as outpatients under local anesthesia in Stellenbosch, South Africa, enrolled January 1991 to January 1994.
- Arms
- Optical internal urethrotomy versus filiform dilation
- Report and follow-up
- 1997 · Life-table analysis to 48 months
| Endpoint | Results | Effect | Finding |
|---|---|---|---|
| Stricture recurrence by life-table survival analysis, urethrotomy versus dilation | No significant difference between the two treatments; arm-specific rates are not reported in the abstract. | P not significant | |
| Hazard function of recurrence over time (both treatments) | Risk of recurrence was greatest at 6 months; risk of failure after 12 months was slight. | — | Descriptive |
| Recurrence at 12 months, strictures shorter than 2 cm (both treatments) | Approximately 40%. | — | Descriptive |
| Recurrence at 12 and 48 months, strictures 2 to 4 cm (both treatments) | Approximately 50% at 12 months, rising to approximately 75% at 48 months. | — | Descriptive |
| Recurrence at 12 months, strictures longer than 4 cm (both treatments) | Approximately 80%. | — | Descriptive |
Registry not recorded · Report DOI
Design
The 210 men had proven urethral strictures and were randomized between January 1991 and January 1994 in the urology department of Stellenbosch University at Tygerberg Hospital.[2] Follow-up visits were scheduled at 3, 6, 9, 12, 24, 36 and 48 months, and either procedure was repeated at the first and second stricture recurrence.[2] The EAU guideline describes the enrolled strictures as non-obliterative and at all levels of the urethra, with retrograde urethrography at the follow-up visits.[3]
The initial report compared stricture recurrence between the two procedures with life-table survival analysis and examined the timing of failure with a hazard function. A Cox regression tested stricture length as a predictor of recurrence.[1] The 1998 report of the same cohort estimated time to first recurrence with the Kaplan-Meier method and compared groups with the log-rank test.[2]
Results
Life-table analysis showed no significant difference between urethrotomy and dilation in stricture recurrence. The hazard of recurrence was greatest at 6 months and slight after 12 months.[1]
Stricture length predicted failure in both arms. Recurrence at 12 months was approximately 40% for strictures shorter than 2 cm and approximately 80% for strictures longer than 4 cm; for strictures of 2 to 4 cm it rose from approximately 50% at 12 months to approximately 75% at 48 months. Each additional centimeter of stricture length raised the hazard of recurrence by a factor of 1.22 (95% CI 1.05 to 1.43). The authors recommended dilation or urethrotomy for strictures shorter than 2 cm, primary urethroplasty for strictures longer than 4 cm, and a trial of dilation or urethrotomy for strictures of 2 to 4 cm.[1]
The 1998 analysis followed 163 of the 210 men (78%) for a mean of 24 months (range 2 to 63) and examined repeated treatment, reporting dilation and urethrotomy together. Among 73 of 107 men at risk (68%) who were stricture-free at 3 months after one study procedure, estimated stricture-free survival was about 60% at 24 and 48 months in the analysis including men with and without previous treatment; alternate analyses yielded 55 to 60% at 24 months and 50 to 60% at 48 months. After a second study procedure for recurrence at 3 months, estimated stricture-free survival was about 30% at 24 months and 0% at 48 months in the analysis including men with and without previous treatment, or about 40% and 0% among men without previous treatment; when pre-study treatment is counted as the first treatment, the estimates after a second treatment were about 50% at 24 months and 40% at 48 months, and 0% at both time points after a third. After a third procedure for recurrence at 3 and 6 months, estimated stricture-free survival was 0% at 24 months; the comparison across one, two and three procedures gave p < 0.0001.[2]
Surgery and treatment delivery
Both procedures were done as outpatient procedures under local anesthesia: dilation with filiforms and optical internal urethrotomy.[1] A report on how the procedures performed in the same 210 men found cumulative recurrence did not differ between the arms at a mean follow-up of 15 months.[4] For the performance of the procedure itself, the authors judged multiple, longer (more than 2 cm), post-traumatic and previously untreated strictures better managed with dilation, and men presenting with complications or retention better managed with urethrotomy.[4]
Adverse events
Complications or failure during the procedure did not differ significantly between dilation and urethrotomy. A positive urine culture was associated with more complications or failure in both procedures. Dilation complications or failure were also more frequent in men presenting with retention or complications than with symptoms only. Urethrotomy complications or failure were more frequent with strictures longer than 2 cm than with shorter strictures (multiple strictures, P = 0.06), and failure of urethrotomy alone was more frequent in post-traumatic than post-urethritic strictures and in men without previous stricture treatment.[4]
Limitations
The trial took place at one academic department between 1991 and 1994. The 1998 analysis had follow-up for 163 of 210 men (78%), and its second- and third-procedure estimates describe men who recurred at 3 or 6 months and were retreated, not the randomized groups.[2]
In conversation
Later randomized stricture trials used endoscopic treatment as the comparator in recurrent disease. OPEN compared urethroplasty with urethrotomy in recurrent bulbar strictures, and ROBUST III compared a paclitaxel-coated balloon with standard dilation or urethrotomy after at least two endoscopic treatments.
Guidelines and approvals
- AUA Urethral Stricture Disease guideline (2023 amendment). Surgeons may offer urethral dilation, direct visual internal urethrotomy or urethroplasty for the initial treatment of a short (<2 cm) bulbar urethral stricture . The discussion cites this trial among its sources for similar long-term outcomes of dilation and direct visual internal urethrotomy in short strictures. Surgeons may perform either dilation or direct visual internal urethrotomy when treating a stricture endoscopically .[5]
- EAU Urethral Strictures guideline (limited update 2026). The guideline calls this the only high-level evidence study comparing dilatation with direct vision internal urethrotomy (DVIU) and states that the two are equally effective but lose effectiveness with increasing stricture length (section 6.2.1.a.1). It finds no evidence that dilatation is superior to DVIU or the reverse, so single dilatation has the same indications as DVIU (section 6.2.2.b). It recommends DVIU or dilatation for a primary, single, short (<2 cm), non-obliterative bulbar stricture and advises against DVIU or dilatation as solitary treatment for long (>2 cm) strictures .[3]
Report history
| Published | Report | Cutoff | Headline results | Citation |
|---|---|---|---|---|
| 1997 | Initial report · primary | — | Stricture recurrence by life-table survival analysis, urethrotomy versus dilation: No significant difference between the two treatments; arm-specific rates are not reported in the abstract.; P not significant Hazard function of recurrence over time (both treatments): Risk of recurrence was greatest at 6 months; risk of failure after 12 months was slight.; — Descriptive Recurrence at 12 months, strictures shorter than 2 cm (both treatments): Approximately 40%.; — Descriptive Recurrence at 12 and 48 months, strictures 2 to 4 cm (both treatments): Approximately 50% at 12 months, rising to approximately 75% at 48 months.; — Descriptive Recurrence at 12 months, strictures longer than 4 cm (both treatments): Approximately 80%.; — Descriptive Hazard of recurrence per 1 cm increase in stricture length, Cox regression: —; HR 1.22; CI 1.05–1.43 | Steenkamp JW, Heyns CF, de Kock ML. Internal urethrotomy versus dilation as treatment for male urethral strictures: a prospective, randomized comparison. *J Urol.* 1997;157(1):98-101. DOI |
| 1997 | Procedure complications and failure · secondary | — | Cumulative percentage of recurrent strictures, urethrotomy versus dilation: No significant difference between the two treatments at mean follow-up of 15 months.; P not significant | Steenkamp JW, Heyns CF, de Kock ML. Outpatient treatment for male urethral strictures: dilatation versus internal urethrotomy. *S Afr J Surg.* 1997;35(3):125-130. |
| 1998 | Repeated-treatment analysis · secondary | — | Stricture-free rate at 24 and 48 months after one dilation or urethrotomy with no recurrence at 3 months: Among 73 of 107 men at risk (68%) who were stricture-free at 3 months after one study procedure, estimated stricture-free survival was about 60% at 24 and 48 months in the analysis including men with and without previous treatment (Fig. 2); alternate analyses yielded 55 to 60% at 24 months and 50 to 60% at 48 months (Figs. 3–4).; — Stricture-free rate at 24 and 48 months after a second dilation or urethrotomy for recurrence at 3 months: After a second study procedure for recurrence at 3 months, estimated stricture-free survival was about 30% at 24 months and 0% at 48 months in the analysis including men with and without previous treatment (Fig. 2), and about 40% and 0% among men without previous treatment (Fig. 3); in Fig. 4, which counts pre-study treatment as the first treatment, the estimates after a second treatment were about 50% at 24 months and 40% at 48 months, and 0% at both time points after a third.; — Stricture-free rate at 24 months after a third dilation or urethrotomy for recurrence at 3 and 6 months: 0% at 24 months; p < 0.0001 compares the one-, two-, and three-procedure strata, with survival measured from the last treatment.; — | Heyns CF, Steenkamp JW, De Kock ML, Whitaker P. Treatment of male urethral strictures: is repeated dilation or internal urethrotomy useful? *J Urol.* 1998;160(2):356-358. DOI |
References
1. Steenkamp JW, Heyns CF, de Kock ML. "Internal Urethrotomy Versus Dilation as Treatment for Male Urethral Strictures: A Prospective, Randomized Comparison." J Urol. 1997;157(1):98-101. doi:10.1016/S0022-5347(01)65296-0
2. Heyns CF, Steenkamp JW, De Kock ML, Whitaker P. "Treatment of Male Urethral Strictures: Is Repeated Dilation or Internal Urethrotomy Useful?" J Urol. 1998;160(2):356-358. doi:10.1016/S0022-5347(01)62894-5
3. Lumen N, Campos-Juanatey F, Dimitropoulos K, et al. EAU Guidelines on Urethral Strictures. Limited update 2026. Arnhem: EAU Guidelines Office; 2026. Sections 6.2.1.a.1 and 6.2.2.b.
4. Steenkamp JW, Heyns CF, de Kock ML. "Outpatient Treatment for Male Urethral Strictures: Dilatation Versus Internal Urethrotomy." S Afr J Surg. 1997;35(3):125-130. PMID: 9429329
5. Wessells H, Morey A, Souter L, Rahimi L, Vanni A. "Urethral Stricture Disease Guideline Amendment." J Urol. 2023;210(1):64-71. doi:10.1097/JU.0000000000003482