Detection of human papillomavirus type 56 in Bowen's disease involving the nail matrix

Update on Squamous Cell Carcinoma of the Nail Unit: An Human Papillomavirus-Associated Condition

Background

Squamous cell carcinoma (SCC) and SCC in situ (Bowen's disease) are the most common malignancies of the nail unit. They are frequently seen in men over 50 and most commonly affect the fingers. The role of high-risk human papillomavirus (HPV) infection has been identified as a key contributor to the development of nail unit SCC.

Summary

In this review, we aimed to summarize the current state of our understanding of how HPV contributes to nail unit SCC, the role of genitodigital transmission of HPV, and the clinical features of HPV-associated nail unit SCC. We also review current advances in the treatment of nail unit SCC, with a focus on the potential role of HPV vaccination in the treatment and prevention of nail unit SCC.

Key Messages

Nail unit SCC should be recognized as an HPV-associated disease. HPV vaccination may represent a non-surgical modality for the management of these challenging malignancies in the appropriate clinical setting.

Surface material analysis for human papillomavirus detection in nail Bowen's disease caused by HPV type 58

Over the past few years, cases of human papillomavirus (HPV) infection in nail Bowen's disease have been reported. This disease presents diagnostic challenges due to its similarity to nail malignant melanoma, particularly with respect to the clinical manifestation of black nail streaks. While skin biopsy is usually employed for diagnosis, it is an invasive procedure. We report the case of a 52-year-old healthy Japanese male with a pigmented streak on the nail of the fourth finger of his right hand, which had extended from the central to the lateral nail fold within 4 months. Dermoscopic examination revealed a dark-brown pigmented band with splinter microhemorrhage. Clinically, nail Bowen's disease was suspected. The lesion was excised in strips under local anesthesia. Histopathological examination revealed hyperkeratosis, parakeratosis, papillomatosis, and dyskeratotic cells with atypical nuclei irregularly arranged. Immunohistochemistry using anti-HPV L1 antibody detected HPV-positive cells in the upper epidermis and stratum corneum of the nail matrix. Mucosal high-risk HPV type 58 DNA was detected from brush cytology of the keratotic surface prior to surgery, which was confirmed in formalin-fixed, paraffin-embedded excised samples using polymerase chain reaction (PCR) and subsequent direct DNA sequencing. Our case highlights HPV type 58 as a potential causative agent of nail Bowen's disease and shows that brush cytology of the surface material prior to excision may be a useful and less invasive way for mucosal high-risk HPV detection. PCR analysis of the nail surface could serve as a supplementary diagnostic tool for nail Bowen's disease.

Skin surface material for detecting human papillomavirus infection of skin warts

Warts, caused by human papillomavirus (HPV) infection, have various clinical presentations, making them difficult to differentiate from clavus, callus, and sometimes, squamous cell carcinoma. Although skin biopsies are the gold standard, a less-invasive method of examining these lesions is desired. Ninety patients with warts and related diseases, such as clavus and callus, were recruited to explore new differentiation methods using the surface of the warts. DNA was extracted from three types of specimens in each case: surface swab, shaved hyperkeratotic scale, and post-shaved surface swab. Total DNA was successfully extracted from these three specimens and was sufficient for subsequent HPV DNA detection. We analyzed samples for the HPV type and HPV viral load using polymerase chain reaction (PCR). Fifty-five cases were PCR-positive, and HPV1a, 2a, 4, 27, 57, and 65 were detected. The amount of HPV1a DNA produced was significantly greater than that of other HPV types. Regarding the correlation between the clinical diagnosis and HPV detection, the positive agreement rate was 90.9%, the negative agreement rate was 40.0%, and the overall agreement rate was 71.1%. Ten of the 21 cases clinically diagnosed as plantar warts were PCR-negative, especially in elderly patients. This suggests that it is difficult to distinguish plantar warts from clavus and callus in clinical practice. Although the amount of HPV DNA in the removed keratinization scale was highest for all HPV types, HPV detection by swabbing before and after shaving is also useful for follow-up as well as for differential diagnosis.

Recent advances in cutaneous HPV infection

More than 200 types of human papillomavirus (HPV) have been reported to date and have been associated with various dermatological diseases. Among dermatological diseases, viral verrucae are the most commonly reported to be associated with HPV. Epidermodysplasia verruciformis (EV) consists of three types: typical EV is an autosomal recessive genetic disorder with TMC6/TMC8 gene mutations, atypical EV develops due to various gene mutations that cause immunodeficiency, and acquired EV develops due to acquired immunodeficiency. Generalized verrucosis differs from EV in that it involves numerous verrucous nodules (mainly on the limbs), histopathologically no blue cells as seen in EV, and infection with cutaneous α-HPVs as well as β-HPVs. HPV-induced skin malignancies include squamous cell carcinoma (SCC) caused by β-HPV (especially HPV types 5 and 8) in EV patients, organ transplant recipients, and healthy individuals, and SCC of the vulva and nail unit caused by mucosal high-risk HPV infection. Carcinogenesis of β-HPV is associated with sunlight. Mucosal high-risk HPV-associated carcinomas may also be sexually transmitted. We focused on Bowen's disease of the nail, which has been the subject of our research for a long time and has recently come to the fore in the field of dermatology.

Viruses and Skin Cancer

Advances in virology and skin cancer over recent decades have produced achievements that have been recognized not only in the field of dermatology, but also in other areas of medicine. They have modified the therapeutic and preventive solutions that can be offered to some patients and represent a significant step forward in our knowledge of the biology of skin cancer. In this paper, we review the viral agents responsible for different types of skin cancer, especially for solid skin tumors. We focus on human papillomavirus and squamous cell cancers, Merkel cell polyomavirus and Merkel cell carcinoma, and human herpesvirus 8 and Kaposi’s sarcoma.

Nail squamous cell carcinoma: A hidden high-risk human papillomavirus reservoir for sexually transmitted infections

Human papillomavirus (HPV) causes cervical cancer, anal cancer, vulvar cancer, vaginal cancer, penile cancer, and oropharyngeal cancer. Squamous cell carcinoma (SCC) in the genital region in particular is recognized to be caused by HPV infection, and intraepithelial lesions of the penis and vulva are termed penile intraepithelial neoplasia and vulvar intraepithelial neoplasia, respectively. Although SCC of the nail apparatus is recognized as being associated with high-risk HPVs, it is not well-known in general medicine, and its analysis has been insufficient. In this article, we reviewed 136 cases of HPV-associated nail SCC and SCC in situ and delineated their clinical characteristics. We found that half of the cases were high-risk HPV-associated. Almost all of the types were high-risk α-HPVs. This disease had a male dominance and left hand digit 3 and right hand digits 1-3 were typically affected. In this review, 24% of the cases of nail SCC had a history of other HPV-associated diseases, suggesting the possibility of genitodigital transmission. We propose that nail SCC is a hidden high-risk HPV-associated reservoir and should be recognized as a sexually transmitted infection.

Nail neoplasms

Nail neoplasms include all tumors occurring in the nail or periungual apparatus tissue. While some nail tumors can be similar to tumors located on the skin, others are unique. Both benign and malignant lesions can affect the nail apparatus. In particular, early malignant tumors like melanoma and squamous cell carcinoma can present similarly to onychomycosis or benign melanonychia and frequently missed by clinicians. Therefore, physicians should be aware of nail structures and the characteristics of nail tumors. Our review covers the normal nail structure and the most common nail tumors from benign to malignant.

A Retrospective Study of Nail Squamous Cell Carcinoma at 2 Institutions

BACKGROUND

Squamous cell carcinoma (SCC) of the nail is infrequently reported in the medical literature and its causes are poorly understood. Studies have shown strong associations with immunosuppression, tobacco use, toxin/radiation exposure, and trauma. Common treatments include Mohs surgery and digital amputation.

OBJECTIVE

Review a series of nail SCCs treated at 2 institutions. Outcomes evaluated included rates of recurrence and disease progression/metastasis after treatment.

MATERIALS AND METHODS

A retrospective review of patients treated between 2005 and 2008. Medical record review and phone call follow-up using a standardized questionnaire were used.

RESULTS

Forty-two tumors were identified in 34 patients. Twenty-seven patients were male (79% CI, 62%-91%) and most tumors were located on the fingernails (39/42; 91% CI, 81%-99%). Twenty-four of 39 tumors (62% CI, 45%-77%) were on the nondominant hand. The middle third finger was the most frequent digit affected (16/42). Common symptoms reported were nail dystrophy (31/42; 74% CI, 58%-86%), followed by onycholysis (22/42; 52% CI, 36%-68%). Most tumors (35/42; 83% CI, 69%-93%) were treated with Mohs surgery.

CONCLUSION

Nail SCC is found nearly exclusively in adults and predominantly in men. There are multiple effective treatment possibilities including Mohs surgery, distal digital amputation, and early evidence suggesting radiotherapy.

Bowen's disease of the nail apparatus: a series of 8 patients and a literature review

Bowen's disease of the nail apparatus is uncommon. Since often characteristic clinical features are missing, diagnosis and treatment are delayed. We have analyzed our patients' files from January 2001 to July 2015 for this disorder. We identified eight patients with Bowen's disease of the nail apparatus, six male and two female individuals. Fingers were more often affected than toes. The disease does not respect the anatomical borders of the nail apparatus. Therefore, we performed delayed Mohs surgery with skin grafts in seven patients and with second intention healing in one patient. Two relapses were noted but only one ate the same digit. Since relapses occurred after 2-3 years, a follow-up of such patients seems justified.

Bowenoid papulosis successfully treated with imiquimod 5% cream

A 24-year-old healthy Japanese female was diagnosed as having bowenoid papulosis in the genital area. The histopathological findings revealed acanthosis, papillomatosis, dyskeratotic cells and clumping cells with mild atypical nuclei. Human papillomavirus type 16 was detected in the lesion. The lesion was successfully treated with topical imiquimod 5% cream after 2 months. Imiquimod 5% cream is a potentially effective treatment modality for lesions that are difficult to treat with surgical excision.

Successful treatment of genital Bowen’s disease with imiquimod 5% cream

A 64-year-old Japanese woman was diagnosed as having Bowen’s disease on the vulva. The histopathological findings revealed papillomatosis, koilocytosis and clumping cells with atypical nuclei. Human papillomavirus DNA was not detected on polymerase chain reaction using consensus primers. The lesion was successfully treated with topical imiquimod 5% cream after two months. Histopathologically, no atypical cells were observed after treatment. Imiquimod can be a potential treatment modality for lesions that are difficult to treat with surgical excision.