Condyloma acuminata: Genital Warts caused by Human Papillomavirus
References: (CDC Guidelines, 2006) (Höpfl et al, 2001 ) (Micali et al, 2004).
Condylomata acuminata are papillomatous proliferations of the squamous epithelium of the external genitals, caused by human papillomavirus (HPV).
Epidemiology of Genital Warts
Very common disease, the exact prevalence is unknown. The viral prevalence is 40–60% in sexually active women and 5–20% in married men. The manifestation of condyloma acuminata is seldom before sexual activity, but the occurrence of genital warts in children is not an evidence of child abuse.
Risk factors for genital warts are similar to other sexually transmitted diseases: sexually active young people with multiple partners, lack of circumcision, lack of condom use, homosexuals.
Etiology of Condyloma Acuminata
Human papillomavirus (HPV):
HPV is a DNA virus from the group of polyomaviruses. More than 100 types of papillomavirus are known so far. Sexual transmission causes the typical papillomatous lesions, especially HPV type 6, 11, 42–44. HPV is very resilient and can be transmitted using fingers or inanimate vectors.
HPV is of icosahedral shape, size 60 nm. HPV contains double-stranded DNA; the genome is 8000 base pairs in size.
The persistence of viral DNA in adjacent epithelial cells is responsible for the high recurrence rate. The cellular immune system is responsible for the eradication of the infection, diseases affecting the cellular immune system (HIV, tumors...) lead to insufficient eradication, relapse and disease progression.
Human papillomavirus are important tumor inductor for penile cancer and cervical cancer. DNA of HPV is detectable in nearly 100% of precancerous lesions and in 50% of invasive penile carcinomas. The typical clinical lesions with high-risk papillomaviruses are flat warts, Condyloma plana; they are mainly caused by the HPV 16, 18, 31 and 33. The transmission of HPV between women and men and vice versa leads also to the transmission of cancer risks.
Molecular mechanisms of tumor induction:
HPV 16 infection is an important risk factor for invasive carcinomas, also HPV 18, 31 and 33. The first step of tumor induction by HPV infection is the expression of viral oncogenes (E6 and E7), this leads to rapid degradation of p53 or pRB tumor suppressor gene proteins and immortalized cells. The second step of the carcinogenesis (e.g. a spontaneous mutation) transforms the immortalized cell into a cancer cell.
Pathology of Condyloma Acuminata
Soft, reddish brown papillomatous tumors of the genital skin.
Hyperkeratosis (thickening of the stratum corneum), acanthosis (diffuse epidermal hyperplasia), koilocytosis (cells with halo nuclei).
Signs and Symptoms
Soft, reddish brown papillomatous or flat tumors of the genital skin. They typically grow in clusters [fig. condyloma acuminata of the penis].
Typical manifestations are the external genitals, inguinal region, perineal region, urethra, mouth, anus and rectum.
HPV-infection can result in giant condyloma acuminata of the penis with aggressive growth (Buschke-Löwenstein tumor, verrucous penile cancer).
There is an increased risk of premalignant lesions or cancer: CIN (cervical), VIN (vulvar), PIN (penile), PAIN (perianal), VAIN (vaginal), Bowen's disease or Erythroplasia Queyrat, penile cancer, vulvar or cervical cancer.
Diagnosis of Condyloma Acuminata
Careful inspection of the external genitalia, the inguinal region and the perianal region. The incubation with 5% acetic acid improves the identification of subclinical lesions (whitish-gray discoloration).
Necessary with involvement of the meatus. The cystoscopy should be performed only after the therapy of visible condylomatat acuminata of the external genitalia.
Necessary with lesions of the anus.
A skin biopsy should be done when there are doubts about the clinical diagnosis or before operative treatment.
Molecular typing has no place in diagnostic routine. It uses PCR, Southern blot or hybrid capture technique (Antibody detects DNA) and can identify the relevant HPV subtypes.
The examination (and therapy) of all sexual partners is necessary.
Treatment of Condyloma Acuminata
Eradication of the virus is often not possible. Therapy aims at the elimination of exophytic lesions and the prevention of further spread.
One cycle of therapy is seven days long, initial treatment should be 4 cycles. 0.3–0.5% podophyllotoxin solution 2× daily for 3 days, then four days off therapy.
5% cream 3× per week for 6–7 month. The immunomodulatory effect causes the release of interferon and tumor necrosis factor. This leads to a cure of 35–50%, as shown in several randomized trials. The treatment is very expensive.
80% trichloroacetic acid 1–2× per week for six weeks, suitable for smaller lesions.
If the lesions involve the prepuce, a circumcision is necessary.
Before laser treatment, the diagnosis is confirmed by biopsy. The laser therapy leads to a heat necrosis of the lesions.
Endoscopic laser coagulation of urethral lesions or therapy with 5% 5-fluorouracil ointment.
- Use of condoms
- Avoidance of the above mentioned risk factors
- Tetravalent HPV vaccine against HPV 6, 11, 16 and 18 (Gardasil) before reaching sexual maturity.
Prognosis of Condyloma Acuminata
Most of the HPV infection goes unnoticed, the virus infection either heals spontaneously or persists. The virus persistence in epithelial cells around the lesion is responsible for the high relapse rate. At present, a curative therapy does not exist.
Index: 1–9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Center for Disease Control and Prevention.:
- Sexually transmitted diseases treatment guidelines 2006.
2006; 55 (No. RR-11): 1–93.
Höpfl u.a. 2001 HÖPFL, R. ; GUGER, M. ;
- Humane Papillomviren und ihre Bedeutung in der Karzinogenese.
52 (2001), S. 834–846
Micali u.a. 2004 MICALI, G. ; DALL'OGLIO, F. ;
NASCA, M. R. ; TEDESCHI, A.:
- Management of cutaneous warts: an evidence-based approach.
In: Am J Clin Dermatol
5 (2004), Nr. 5, S. 311–7