The acetic acid test in evaluation of subclinical genital papillomavirus infection: a comparative study on penoscopy, histopathology, virology and scanning electron microscopy findings

Therapeutic Approaches to Penile Cancer: Standards of Care and Recent Developments

Penile cancer is a rare malignancy, most commonly diagnosed in older men, associated with poor outcomes, dramatic decline in quality of life and sexual function. Squamous cell carcinoma is the most common histopathology of penile cancer, accounting for 95% of all cases. Localized, early-stage penile cancer can be effectively managed through penile-sparing techniques in many cases, though advanced stages of penile cancer carry a poor prognosis. Current innovative treatments are exploring the role of targeted therapy, HPV-directed therapy, immune checkpoint inhibitors and adoptive T-cell therapies in treatment and prevention of relapse of penile cancer. Clinical trials are investigating the potential of targeted therapies and immune checkpoint inhibitors in advanced penile cancer. This review examines the current management of penile cancer and highlights future directions in research and treatment.

An update on treatment of penile cancer

Penile cancer is a rare malignancy, particularly in industrialized nations. In the United States, rates are approximately less than 1 per 100,000 men per year with just over 2000 new cases per year. However, there is significantly increased prevalence in developing nations, with limited treatment expertise and reduced access to care, further driving an unmet clinical need. The most noteworthy risk factor for penile cancer is the association with human papillomavirus infection, which may be present in up to 50% of all penile carcinomas. In addition to local primary tumor approaches, multimodality treatment strategies are vital to patients with clinical regional nodal disease, locally advanced disease. Presence and degree of lymph node involvement remains the most important prognostic factor and patients may benefit from multiple treatment strategies. Interim analysis data from the first randomized clinical trial is expected to yield results in mid/late 2024–early 2025. These treatment approaches include neoadjuvant chemotherapy, adjuvant therapy, including chemotherapy and radiation. Systemic therapy for distant recurrent or metastatic disease is primarily a platinum-based chemotherapy, however with poor overall response. As poor outcomes remain high, particularly in indigent populations, there remains an unmet need for these patients, particularly for high level randomized trials and novel therapeutics. In this review, we will highlight treatment updates for penile cancer. In addition to standard of care, we will review novel lines of therapies including immunotherapies and targeted therapies as well as sequencing approaches.

Topical Therapy for non-invasive penile cancer (Tis)-updated results and toxicity

Penile cancer is a rare malignancy estimated to affect 26,000 men globally each year. The association with penile cancer, in particular non-invasive disease, and human papilloma virus (HPV) is well known. Ninety-five percent of cases of penile cancer are squamous cell carcinoma (SCC), which are staged using the TNM staging system. Terminology describing the histological appearance of non-invasive penile cancer has changed with all cases grouped under the umbrella term of penile intraepithelial neoplasia (PeIN); either undifferentiated or differentiated. This replaces previous terms such as carcinoma in situ (CIS) and eponymous names such as Bowen's disease. This change is recognised by the World Health Organisation (WHO). The topical treatments most commonly used for PeIN are 5-fluorouracil (5-FU) and imiquimod (IQ). Other treatments such as photodynamic therapy (PDT) are used but to a lesser degree. The evidence for all of these treatments is heterogenous with no randomised data available. Overall up to 57% complete response has been reported with a low number of serious adverse events. In this article, we aim to review the available evidence for the topical treatment of non-invasive penile cancer specifically regarding its efficacy and toxicity.

Treatment of condyloma acuminata in pregnant women with cryotherapy combined with proanthocyanidins: Outcome and safety

Patients with condyloma acuminata (CA) during pregnancy represent a special risk group. The outcomes of many treatment methods for such cases are not satisfactory. The purpose of the present study was to evaluate the treatment outcome and safety of cryotherapy combined with proanthocyanidins (PCs) for CA in pregnant women. In this study, 46 pregnant women with CA were treated with cryotherapy combined with PCs. The lesions were sprayed with liquid nitrogen until the color of the wart changed from flesh colored to purple. A PC-containing formulation was then sprayed onto a non-woven fabric or single-layer gauze and applied to the affected area. The PC treatment was applied for 20 min, 2 or 3 times per day. All patients were followed up at 1 and 3 months. No visible warts remained after the cryotherapy and PC treatment. At the 1-month follow-up, only 1 case of recurrence was identified. At 3 months, 5 cases of recurrence were identified, and the recurrence rate was 10.9%. The satisfaction rate of the patients was 94% at 1 month and 87% at 3 months after treatment. All pregnancies resulted in healthy live births without delivery complications. Cryotherapy combined with PCs is indicated to be a safe and effective procedure and may serve as a treatment option for pregnant women with CA.

Role of histological findings and pathologic diagnosis for detection of human papillomavirus infection in men

Early HPV infection in males is difficult to detect clinically and pathologically. This study assessed histopathology in diagnosing male genital HPV. External genital lesions (n = 352) were biopsied, diagnosed by a dermatopathologist, and HPV genotyped. A subset (n = 167) was diagnosed independently by a second dermatopathologist and also re-evaluated in detail, tabulating the presence of a set of histopathologic characteristics related to HPV infection. Cases that received discrepant diagnoses or HPV-related diagnoses were evaluated by a third dermatopathologist (n = 163). Across dermatopathologists, three-way concordance was fair (k = 0.30). Pairwise concordance for condyloma was fair to good (k = 0.30-0.67) and poor to moderate for penile intraepithelial neoplasia (k = -0.05 to 0.42). Diagnoses were 44-47% sensitive and 65-72% specific for HPV 6/11-containing lesions, and 20-37% sensitive and 98-99% specific for HPV 16/18. Presence of HPV 6/11 was 75-79% sensitive and 35% specific for predicting pathologic diagnosis of condyloma. For diagnosis of penile intraepithelial neoplasia, HPV 16/18 was 95-96% specific but only 40-64% sensitive. Rounded papillomatosis, hypergranulosis, and dilated vessels were significantly (P < 0.05) associated with HPV 6/11. Dysplasia was significantly (P = 0.001) associated with HPV 16/18. Dermatopathologists' diagnoses of early male genital HPV-related lesions appear discordant with low sensitivity, while genotyping may overestimate clinically significant HPV-related disease. Rounded papillomatosis, hypergranulosis, and dilated vessels may help establish diagnosis of early condyloma.

Aminolevulinic acid (ALA)-assisted photodynamic diagnosis of subclinical and latent HPV infection of external genital region

The relatively high recurrence rate of genital warts can be attributed to the unsuccessful elimination of viruses in areas of subclinical and latent infection. Therefore, the identification and treatment of the subclinical and latent infection is a key to reduce the recurrence. The goal of this study is to investigate the usefulness of 5-aminolevulinic acid (ALA)-assisted in situ fluorescence diagnosis of subclinical lesion and latent HPV infection. A total of 30 patients with histologically confirmed genital warts (condylomata acuminata) were subjected to topical application of ALA, acetic acid test, histopathologic examination and HPV DNA subtyping. Topical application of ALA was performed by applying 20% ALA cream to the lesion plus 2-cm margin for 2h followed by fluorescence examination. Correlations between histopathologic examination, aceto-whitening test, HPV DNA subtyping and fluorescence were examined. All warty lesions and subclinical lesions (n=25) showed red fluorescence and harbored HPV DNA (HPV6 or 11). Latent HPV infections at 0.5-2 cm away from the warty lesion also showed red fluorescence. Nonspecific fluorescence was associated with mucosa, inflammatory infiltration and erosive lesion. ALA-assisted photodynamic diagnosis could be employed for the detection of the lesion and subclinical lesion of genital warts. It is also useful in detecting latent HPV infection.

European course on HPV associated pathology: guidelines for primary care physicians for the diagnosis and management of anogenital warts

The European Course on HPV Associated Pathology (ECHPV) was founded in 1990 by a group of clinicians, pathologists, and virologists to teach important principles for the practice and management of human papillomavirus (HPV) disease to gynaecologists, dermatologists, and other medical disciplines. These guidelines are intended to assist the practice of primary care physicians for diagnosis and treatment of anogenital warts.

Papillomavirus-associated balanoposthitis

OBJECTIVE

To assess whether there might be an association between genital papillomavirus infection (GPVI) and balanoposthitis.

DESIGN

Retrospective HPV DNA examination of biopsy specimens from 23 men suffering from balanoposthitis and exhibiting acetowhite lesions that were penoscopically and histologically concurrent with HPV infection.

SETTING

The STD clinics at Karolinska Hospital and South Hospital, Stockholm, Sweden.

PARTICIPANTS

Randomly selected men attending with long-lasting and/or recurrent penile symptoms and exhibiting a clinical picture of balanoposthitis, who revealed a penoscopical and histopathological picture of epidermal lesions that were concordant with accepted criteria for typical or conspicuous GPVI. Asymptomatic controls were selected retrospectively on the basis of identical penoscopy and histology criteria.

RESULTS

A history of previous condylomata was obtained in eight (35%) of 23 men. At penoscopic evaluation tiny condylomatous lesions were observed in five (22%) patients. The in situ hybridisation (ISH) assay using specific probes for the HPV types 6/11, 16/18, 31/33 and 42 was positive in 13/23 (56%) of the patient samples, but in only 26% of the 19 control samples. In patient biopsies the oncogenic HPV types 16/18 and/or 31/33 were found in 7/13 samples, whereas HPV 6/11 and/or 42 were present in another six cases. PCR performed on the ten ISH negative patient biopsies, were negative in all cases.

CONCLUSION

Symptoms included redness, itching, burning, tenderness, dyspareunia, fissuring and in two cases penile oedema and inguinal adenopathy. All patients fulfilled penoscopical and histopathological criteria for HPV infection. We demonstrate some tentative evidence that HPV might be associated with long-lasting balanoposthitis, although our data still are circumstantial for a causative association. The results also elucidate the diversity in clinical presentation of GPVI.

Genital human papillomavirus infection among patients attending an STD clinic

OBJECTIVES--To determine the prevalence of human papillomavirus (HPV) infection in patients, male and female, attending a clinic for sexually transmitted diseases (STDs). DESIGN--A randomly selected group of patients representative of the population studied and first-time visitors to the STD clinic, were asked to participate in the study. Samples from the skin and mucous membranes of the lower genital region were taken for cytological analysis by the polymerase chain reaction (PCR) method for HPV DNA. The patients then underwent colposcopy or peniscopy after acetic acid application. SETTING--Department of Dermatology and Venereology, University Hospital, Uppsala, Sweden. SUBJECTS--A total of 131 patients, 66 women and 65 men, attending the clinic for various reasons. RESULTS--At colposcopy/peniscopy, 18 patients (10 men and 8 women) had lesions typical of, and 24 (12 men and 12 women) suspicious of HPV infection. With the PCR technique HPV DNA was detected in 72% of the patients with typical lesions and in 54% of those with suspicious lesions. CONCLUSION--Nearly one-third or 30.5% of these randomly selected patients in a Swedish STD clinic were infected by HPV. The diagnosis was made by clinical inspection and/or by HPV DNA analysis with PCR.

Human papillomavirus DNA in the urogenital tracts of men with gonorrhoea, penile warts or genital dermatoses

OBJECTIVE

To assess the presence of human papillomavirus (HPV) DNA in urethral and urine specimens from men with and without sexually transmitted diseases.

DESIGN

Prospective study.

SETTING

Two London departments of genitourinary medicine

PATIENTS

100 men with urethral gonorrhoea, 31 men with penile warts and 37 men with genital dermatoses.

METHODS

Urethral and urine specimens were taken, HPV DNA extracted and then amplified using the polymerase chain reaction. HPV types 6, 11, 16, 18, 31 and 33 were identified using Southern blotting followed by hybridisation.

RESULTS

HPV DNA was detected in 18-31% of urethral swab specimens and in 0-14% of urine specimens. Men with penile warts had HPV detected in urethral swabs more often than did men in the other two clinical groups. "High risk" HPV types were found in 71-83% of swab specimens and in 73-80% of urine specimens containing HPV DNA.

CONCLUSIONS

HPV is present in the urogenital tracts of men with gonorrhoea, penile warts and with genital dermatoses. In men with urethral gonorrhoea, detection of HPV in urethral specimens is not related to the number of sexual partners, condom usage, racial origin or past history of genital warts. HPV DNA in the urethral swab and urine specimens may represent different aspects of the epidemiology of HPV in the male genital tract. The preponderance of HPV types 16 and 18 in all three groups of men may be relevant to the concept of the "high risk male".

Use of Probemix and OmniProbe biotinylated cDNA probes for detecting HPV infection in biopsy specimens from the genital tract

AIMS

To compare two commercially available pan probes for the identification of human papillomavirus (HPV) DNA expression in histological sections and to type the HPV positive cases.

METHODS

97 formalin fixed, paraffin wax embedded biopsy specimens from the genital tract were tested for HPV positivity with in situ hybridisation using biotinylated cDNA pan probes--Probemix (Enzo) and OmniProbe (Digene). The HPV positive cases were further tested with HPV types 6/11, 16/18, and 31/33/35/51, and the HPV type was related to the histological diagnosis. Formalin fixed, HeLa cells (10-50 HPV 18 copies per cell) and SiHa cells (1-2 HPV 16 copies per cell) were used as reference cell lines.

RESULTS

32% of the specimens gave positive nucleic signals with both Probemix and OmniProbe. Of these, 84% could be further characterised with regard to HPV types 6/11, 16/18, and 31/33/35/51; 4% of all cases were positive with either Probemix or OmniProbe. The concordance of these probes was high, 96% altogether. HeLa cells stained positive but SiHa cells did not.

CONCLUSION

There is no difference between Probemix and OmniProbe for the general detection of HPV. The mean detection limit of these probes is about 20 copies a cell.

Genital HPV infection not a local but a regional infection: experience from a female teenage group

OBJECTIVES

To investigate the prevalence of human papillomavirus (HPV) infections in a group of female teenagers, and to analyse to what extent HPV DNA was also detectable, in urethra and cervix samples among the patients with macroscopic genital warts compared with those without.

DESIGN

The patients were interviewed about their sexual habits and history of venereal diseases. They underwent a gynaecological health control examination, including macroscopic inspection for genital warts and collection of a cytological vaginal smear (Pap smear). Cell samples were also taken from endocervix and urethra and from vulva lesions, when found. These samples were tested for HPV DNA of the types 6, 11, 16, 18 and 33 using the polymerase chain reaction (PCR) technique.

SETTING

An adolescence out-patient clinic in Malmö, Sweden.

SUBJECTS

Forty-nine female teenagers consulting for gynaecological complaints, some of them for genital warts.

RESULTS

Twenty patients had present and four had a history of genital warts (group A). The other 25 patients had no visible lesions (group B). In the first group (A) 18 of the 24 patients were positive for HPV DNA in one or more of the three locations studied. More patients were positive in urethra (17) than in cervix (15). In group B four of the 25 patients were positive for HPV DNA in urethra, three of these also in cervix. In the two groups 11 and four patients, respectively, showed pathological Pap smears.

CONCLUSIONS

The finding of HPV DNA in urethra, both from women with and without visible genital warts, indicates that there is a high probability that the infection is also present in cervix, suggesting that the genital HPV infections are multifocal. Thus, patients with genital warts are most likely to have cervical HPV infections and will more often have pathological Pap smears than patients without warts.

Dual genitotropic human papillomavirus infections in genital warts

BACKGROUND AND METHODS

We have carried out a prospective study of dual genitotropic human papillomavirus (HPV) infections by means of two different DNA detection methods in biopsy specimens obtained from patients who were examined for genital warts at the STD clinic of the School of Medicine in Seville, between January 1990 and December 1991.

RESULTS

100 patients with a clinical diagnosis of condilomata acuminata were seen during the study period. DNA of the genitotropic HPV 6/11, 16/18 and 31/33/35 was detected by an in situ hybridisation method in 75 (77%) of the 98 evaluable samples; one of the genotypes tested in 59 (61%) samples, and two or more genotypes tested in the remaining 16 (15%) samples. In 21 (98%) of the 23 negative samples by in situ hybridisation, we were able to detect DNA of genital HPV using a polymerase chain reaction amplification method (PCR). Among the 34 samples where PCR was applied we confirmed the presence of two different HPV genotypes in eight samples.

CONCLUSIONS

The frequency of dual infections with human genitotropic papillomavirus in genital warts was 8%, although we believe that this rate should be higher as we have not used the PCR method in all of the samples.