A urethral caruncle is a benign granulomatous lesion of the distal urethra (usually posterior wall) covered by transitional epithelium.¹

Epidemiology^1,2

It is uncommon but most often found in postmenopausal women. It can sometimes occur before the menopause and has been known to enlarge in pregnancy. A single case has been reported in a man.³

Presentation

History

Usually there are no symptoms but sometimes they are painful. There may be dysuria and occasionally they may bleed.⁴ It is an unusual cause of postmenopausal bleeding, in one series accounting for 2.5%.⁵

Examination¹

There is a soft smooth red fleshy lesion² or red ring of urethral mucosa protruding through the urethral orifice.⁶ It may appear to be polypoid (sessile or pedunculated). Rarely, they may thrombose and turn purple or black. Urethral caruncles tend to be soft and may be tender whilst malignancy is usually firm and not tender.²

Differential diagnosis^1,2

The main differential diagnosis is with urethral prolapse (occurs in younger women). This is more likely if the woman is around the menopause rather than elderly and almost invariably the case if the lesion is seen before the menarche. Rarities such as non-Hodgkin's lymphoma⁷, intestinal polyp-like lesions⁸, melanoma and tuberculosis have been described. If they are large, necrotic and bleed they may look like urethral carcinoma. Carcinoma can also look like a caruncle.⁹

Investigations

If the diagnosis is clear there is no need for further investigation. If dysuria is present, a mid-stream specimen of urine (MSU) should be sent for microscopy and culture to exclude urinary tract infection. Only if there is uncertainty about diagnosis is cystoscopy and biopsy indicated.

Management⁴

• If the diagnosis is clear and the lesion is asymptomatic then no further action is required.
• In the elderly patient with oestrogen deficiency and symptoms, oestrogen cream may be useful.
• Warm salt baths and anti-inflammatory creams have been recommended.
• If symptoms persist, caruncles can be removed using cauterisation, laser vaporisation or excision. Cryotherapy or surgical excision may also be used.
• Surgical intervention is indicated only if the lesions are large or the diagnosis is uncertain. Primary carcinomas arising from a urethral caruncle are rare but are known to occur.¹⁰ Of these about 2% will show malignancy.¹ If the epithelium is not adequately everted during surgery, meatal stenosis may result.¹

Prognosis¹

If the diagnosis is correct, there is no associated mortality and symptoms, if any, should subside with treatment.

Document references

1. Sajadi KP; Urethral Caruncle, eMedicine, Oct 2009
2. Gomella L; The 5-Minute Urology Consult 2000
3. Karthikeyan K, Kaviarasan PK, Thappa DM; Urethral caruncle in a male: a case report. J Eur Acad Dermatol Venereol. 2002 Jan;16(1):72-3. [abstract]
4. Urethral Caruncle; Merck Manual Chapter 118 Female Genital Disorders 2008
5. Lee WH, Tan KH, Lee YW; The aetiology of postmenopausal bleeding--a study of 163 consecutive cases in Singapore. Singapore Med J. 1995 Apr;36(2):164-8. [abstract]
6. Picture of Urethral Caruncle; iMDimages.MD 2008
7. Khatib RA, Khalil AM, Tawil AN, et al; Non-Hodgkin's lymphoma presenting as a urethral caruncle. Gynecol Oncol. 1993 Sep;50(3):389-93. [abstract]
8. Willett GD, Lack EE; Periurethral colonic-type polyp simulating urethral caruncle. A case report. J Reprod Med. 1990 Nov;35(11):1017-8. [abstract]
9. Cimentepe E, Bayrak O, Unsal A, et al; Urethral adenocarcinoma mimicking urethral caruncle. Int Urogynecol J Pelvic Floor Dysfunct. 2006 Jan;17(1):96-8. Epub 2005 Apr 15. [abstract]
10. Omar A, Thomas A, Thompson I; Primary urethral transitional cell carcinoma presenting as a urethral caruncle. Int Urogynecol J Pelvic Floor Dysfunct. 2007 Oct;18(10):1227-8. Epub 2007 Mar 1. [abstract]

Acknowledgements