Squamous cell carcinoma of the nail bed: a clinicopathological study of 12 cases

Polydactylous Squamous Cell Carcinoma of the Nail Unit: A Structured Review of the Literature

Squamous cell carcinoma of the nail unit (SCCNU) is a rare neoplastic condition that involves multiple digits (polydactylous SCCNU) in only 3.9% of cases. Here, we report a case of polydactylous SCCNU and perform a comprehensive review of MEDLINE and Embase to collate 44 cases of polydactylous SCCNU reported to date. Polydactylous patients were younger on average (48 to 61-63 years) and had a longer diagnostic delay (44 vs 35.1 months) compared with reported monodactylous cases. Human papillomavirus (HPV) positivity was observed in 49% of cases, and the most common serotypes noted were 16 (25.8%), 73 (16.1%), 58 (9.7%), 18 (6.5%), and 33 (6.5%). Twenty percent of the cases were in immunosuppressed individuals who had a statistically significant lower age at diagnosis (39.33 years vs 51.12 years; P = .01) and diagnostic delay (2.50 months vs 132.46 months, P = .04). Patients with HPV positivity had a lower age at diagnosis (43.74 years vs 53.29 years, P = .04). Environmental exposures noted to be associated with polydactylous disease included X-rays, paint/solvents, soluble oils, and stagnant water. This comprehensive literature review serves to characterize polydactylous SCCNU and distinguish the differences in its characteristics to improve diagnosis and clinical recognition.

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.

Acral and Multicentric Pigmented Bowen's Disease in HIV-Positive Patients: Report on Two Unusual Cases

In situ squamous cell carcinoma of the skin (SCCis or Bowen's disease) is a common intraepidermal cutaneous malignancy with a low invasive potential. Acral Bowen's disease is usually solitary, but multiple acral SCCis have been reported. Pigmented Bowen's disease is typically unilesional and characterized by a hyperpigmented plaque with a velvety of keratotic surface, which can eventually simulate melanoma clinically. We describe two HIV-positive patients who presented with multiple pigmented SCCis involving the distal extremities. In patients with immunosuppression, the presence of multiple and hyperpigmented verrucae that clinically do not respond to adequate treatment should raise the differential diagnosis of SCC in situ.

Squamous Cell Carcinoma of the Nail Unit: Review of the Literature

Squamous cell carcinoma of the nail unit (SCCNU) is often misdiagnosed and improperly treated because it mimics a number of other conditions. This review details current knowledge of anatomy, pathophysiology, clinical presentation, diagnosis, and treatment of SCCNU. A heightened clinical awareness is critical to treating SCCNU and preventing development of advanced disease at which time amputation is needed and metastasis may occur. Physicians should consider SCCNU in each case of a nail abnormality unresponsive to topical treatment. For adequate diagnosis and excision of SCCNU, timely and appropriate specialist referral is necessary.

Surgical Treatment of Subungual Squamous Cell Carcinoma by Wide Excision of the Nail Unit and Skin Graft Reconstruction: An Evaluation of Treatment Efficiency and Outcomes

Importance

The best surgical treatment modalities for subungual squamous cell carcinoma (SUSCC) without bone invasion need to be determined. The limited available data on Mohs micrographic surgery do not demonstrate its use as a standard procedure. A previous study in a limited series of patients has shown that wide surgical excision of the nail unit was associated with a low rate of recurrence.

Objectives

To confirm the efficiency of wide surgical excision of the nail unit with full-thickness skin graft reconstruction on a series of patients with SUSCC with an extended follow-up and to evaluate short- and long-term postoperative morbidity and patient satisfaction.

Design, Setting, and Participants

A consecutive series of 55 patients with biopsy-proven SUSCC without bone invasion treated by wide surgical excision of the nail unit followed by full-thickness skin graft reconstruction from January 1, 2000, to August 31, 2012 were included. After a minimum follow-up of 5 years, the recurrences were collected from the referring physicians. Statistical analysis was conducted from January 1 to June 30, 2016.

Main Outcomes and Measures

Demographic data, pathologic characteristics of tumors, postoperative follow-up, and recurrences were collected from medical records. Patients' satisfaction with surgery, quality of life, and delayed postoperative morbidity (functional outcome and sensory disorders) were assessed from a questionnaire mailed to patients and physicians.

Results

Among the 55 patients (23 women and 32 men; mean age, 64 years), the mean follow-up was 6.6 years (range, 5.0-11.2 years), with a minimum follow-up of 5 years. Fifty-two questionnaires (95%) were returned. Two recurrences were observed. Minor early postoperative complications, such as graft infection and delayed wound healing, were seen in 6 patients; 8 patients experienced severe pain. Late postoperative complications included hypersensitivity to mechanical shocks (39 of 51 patients [76%]), mildly increased sensitivity to cold (38 of 51 patients [75%]), loss of fine touch sensation (17 of 35 patients [49%]), and epidermal inclusion cysts (9 of 51 patients [18%]). Most patients were very satisfied with cosmetic and global outcomes of the surgery.

Conclusions and Relevance

Total excision of the nail unit followed by a full-thickness skin graft is a safe and efficient treatment for SUSCC without bone involvement, with satisfying cosmetic and functional outcomes.

Squamous Cell Carcinoma of the Lateral Nail Fold

The digital nail complex is occasionally involved by squamous cell carcinoma. The published literature has either been indiscriminating of the site of origin of this tumour within the nail complex or has concentrated attention on the nail bed as the site of pathology. Tumours originating in the lateral nail fold can be clearly differentiated from those of the nail bed itself. This study identifies six cases of squamous cell carcinoma arising in the lateral nail fold. While surgical convention remains to amputate the digital tip for squamous cell carcinoma of any part of the nail complex, the dermatological literature identifies that local surgery can be curative for these tumours, when presenting early and without bone involvement, although offering no discussion of reconstruction. Reconstruction is desirable and methods of achieving this following local excision of lateral nail fold tumours are illustrated in this series.

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.

Prevalence and Associated Risk Factors of Human Papillomavirus in Healthy Skin Specimens Collected from Rural Anyang, China, 2006-2008

Skin infections with cutaneous human papillomavirus (HPV) have been linked to the development of non-melanoma skin cancer, in which mucosal HPV may also play a crucial role. However, systematic investigations of the distribution and associated factors of HPV infection in healthy skin of the general population are scarce. HPV DNA from palmar exfoliated cells of 2,087 individuals was detected by FAP6085/64 and SPF1/GP6+ primers followed by sequencing. A total of 338 papillomavirus types were detected, with HPV-3, HPV-57, and HPV-49 being the most dominant types. The overall prevalence for HPV DNA on skin was 79.92% and for alpha-, beta-, and gamma-HPV were 27.07%, 38.76%, and 29.56%, respectively. Having multiple lifetime sexual partners (adjusted odds ratio 1.60), being a migrant worker (adjusted odds ratio 2.05, reference: farmers), and frequent bathing (Ptrend = 0.001) were associated with alpha-HPV DNA presence. Advancing age increased the detection risk of beta-HPV (Ptrend = 0.001). Higher education (Ptrend = 0.017) and frequent bathing (Ptrend = 0.001) were positively related to gamma-HPV positivity. This study demonstrates that alpha-HPV commonly exists on healthy skin of the general population in rural China, and alpha- and gamma-HPV infections are related to certain behaviors, different from beta-HPV infection. These findings are crucial to better understanding the biology of HPV infection and may be suggestive of the potential transmission of these viruses.

Diagnosis using the nail bed and hyponychium

"Nails protect the fingertips and toes. Diseases affecting the nail can cause cosmetic disfigurement and social embarrassment. Physical functioning may be impaired. Disorders of the nail bed may cause pain or create difficulty grasping fine objects. The nail bed is the area beneath the nail plate between the lunula and the hyponychium. Disorders of the nail bed can cause onycholysis, subungual hyperkeratosis, and/or onychogryphosis. Ventral pterygium is less common. Tumors of the nail bed are rare and commonly missed."

An unusual lesion of the finger presenting to the emergency department

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Digital squamous cell carcinoma commonly mimics chronic granulomatous or fungal infections.

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Chronic non-healing lesions of the digits should be viewed with suspicion.

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It usually has an indolent course but can be locally destructive.

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Excisional biopsy, providing a clear margin, where possible is usually sufficient in the absence of metastatic spread.

Introduction

Squamous cell carcinoma (SCC) of the finger, especially those arising from the nail bed matrix and lateral skin folds are common, especially after the fifth decade of life. A variety of aetiological factors and associations have been described. The appearance can be so ambiguous and appear benign that it can lead to a delay in presentation and diagnosis.

Presentation of the case

We report a case of a 66 year old retired Engineer who presented to our Emergency Department with a 2-year history of a painless swelling of his left ring finger. Examination revealed a diffuse circumferential swelling of the left ring finger involving the middle and distal phalanx. The tip was insensate. The differential diagnoses included pyogenic granuloma, soft tissue sarcoma and chronic granulomatous infection. An excisional biopsy confirmed the diagnosis of a well differentiated squamous cell carcinoma.

Discussion

This case highlights how digital squamous cell carcinoma can appear benign, mimic a wide variety of conditions leading to a delay in diagnosis and treatment. It usually runs an indolent course but can be locally destructive. Excisional biopsy, providing a clear margin where possible is usually sufficient in the absence of metastatic spread.

Conclusion

Chronic, non-healing lesions of the digits should be viewed with suspicion. Digital squamous cell carcinoma commonly mimics a variety of benign conditions and efforts should be made to rule out other possible diagnoses and to institute early treatment.

Polydactylous subungual squamous cell carcinoma caused by chemical contact

Summary:

Polydactylous squamous cell carcinoma (SCC) is rare and has been associated with human papillomavirus (HPV). Our recent case was HPV negative and provides greater evidence for chemical irritants being an alternative cause of subungual SCC. Our patient had spent a number of years with her hands in direct contact with undiluted cleaning chemicals including one containing ethanolamine. Ethanolamine has been shown to have carcinogen sensitizing role. Although HPV has a strong association with subungual SCCs, the accumulation and concentration of noxious substances around and under the nails must also be considered as a potential cause.

Cutaneous squamous cell carcinoma (SCC) arising in stump of amputated finger in a patient with resected glossal SCC

Background

Cutaneous squamous cell carcinoma (SCC) of the hands and fingers are sometimes locally aggressive; with higher rates of regional metastasis than other cutaneous SCC, although distant metastasis is rare.

Case presentation

We present the case of a 62–year-old Japanese man with double cancers: a tongue SCC and a cutaneous SCC. Swelling of the finger lesion developed gradually around the entire remaining middle finger after accidental amputation at the proximal interphalangeal joint. Histopathological examination of the tumor on the stump of the amputated finger indicated a well-differentiated SCC. The past history indicated surgery for SCC of the tongue 3 years earlier; with histopathology of moderately-differentiated SCC.

Conclusion

Since dedifferentiation is unlikely in metastatic tumors, the cutaneous SCC of the finger is unlikely to have originated from the tongue SCC. Alternatively, the double cancer may be two unrelated lesions or the tongue tumor could have originated from the cutaneous SCC.

Perils of diagnosis and detection of subungual squamous cell carcinoma

Subungual squamous cell carcinoma often presents with atypical clinical manifestations, which can lead to delays in diagnosis. The presence of a tumor can be masked by the presence of infections or other misleading pathological conditions. The authors report on techniques for adequate biopsy and excision of such tumors. A case of subungual squamous cell carcinoma with invasion into the underlying bone is presented. Clinical histopathological evidence is reviewed along with human papillomavirus typing. Accurate diagnosis requires a high index of suspicion and appropriate tissue sampling.

The combined influence of oral contraceptives and human papillomavirus virus on cutaneous squamous cell carcinoma

The vast majority of cutaneous squamous cell carcinoma (CSCC) will occur in those with fair complexion, tendency to burn, and high ultraviolet radiation (UVR) exposure. Organ transplant recipients also are an important population at great risk for CSCC. An association has been reported between oral contraceptive (OC) use, human papillomavirus virus (HPV) and cervical cancer, and there could be a similar association for CSCC. The cutaneous HPV β-E6 protein, a close cousin of the transformative E6 protein underlying anogenital cancers, has been shown to inhibit apoptosis in response to UVR damage and stimulate morphologic transformation in rodent fibroblast cell lines. Furthermore, OC use has been shown to enhance HPV transcription and may contribute to CSCC risk through this pathway.

Subungual squamous cell carcinoma: radiation therapy as an alternative to amputation and review of the literature

We report the outcomes of three patients who were treated with external beam radiotherapy as an alternative to distal phalanx amputation for subungual squamous cell carcinomas between December 2004 and September 2006. The patients' ages ranged from 46 to 83 years and the median follow-up time was 48 months (range: 36-52 months). As of the current date, the three patients show no signs of recurrence following a course of external beam radiotherapy. Complete function of the treated digit was obtained in all three patients. Irradiation should be considered as an alternative modality choice in the treatment of subungual squamous cell carcinoma in lieu of distal phalanx amputation.

Soft Tissue Tumors of the Hand. 2. Malignant

Soft tissue tumors of the hand arise from skin, subcutaneous tissue, tendons, nerve, and blood vessels. Many of these lesions occur on other parts of the body; however, the hand remains a unique site because these tumors have symptoms, appearances, treatments, and prognoses that may be quite different than when on other parts of the body. Their characteristics and the severity of symptoms vary markedly depending on the exact location, size, and type of tumor-and many of these tumors can have multiple forms of presentation. Two articles are intended to provide an overview of benign (previous article) and malignant tumors (this article) of the hand. The rarer and more deleterious tumors are discussed in detail while the common tumors and epidermal lesions with which practitioners are familiar are briefly overviewed. At the completion of these review articles, participants should be able to identify and diagnose various benign and malignant hand tumors as well as understand the accepted current treatment of these growths.

Squamous cell carcinoma of the nail apparatus: clinicopathological study of 35 cases

BACKGROUND

Subungual squamous cell carcinoma (SCC) is rare. Its diagnosis is often missed or delayed because the clinical presentation is often atypical and can mimic other conditions such as verruca vulgaris, onychomycosis, trauma-induced nail dystrophy or exostosis.

OBJECTIVES

To define the different clinical presentations and the main pathological features and to evaluate the most appropriate surgical management of subungual SCC.

METHODS

A retrospective review of all the cases of subungual SCC seen in our institution over a 5-year period.

RESULTS

Thirty-five cases were selected. The spectrum of the clinical features encountered was extremely large including leuconychia, subungual hyperkeratosis, trachonychia, subungual tumoral syndrome, longitudinal erythronychia and melanonychia. Most cases (31 of 35) were invasive. Relapse rate after surgical treatment was low after wide surgical excision (5%) of the nail apparatus or amputation of the digit. However, limited surgical excision led to more frequent relapses (56%).

CONCLUSIONS

Nail apparatus SCC is often misdiagnosed. Most cases are invasive at the time of diagnosis. Wide surgical excision bears a lower risk of relapse. Micrographic surgery should be considered for a better control in cases treated with limited surgical excision.

Common nail tumors

Nail abnormalities are varied and numerous. They include warts, keratoacanthomas, onychomatricomas, fibrokeratomas, osteochondromas, tumors (ie, glomus, giant cell, Koenen's, and others), and Bowen's disease. Although the gravity of these conditions may vary, prompt diagnosis and treatment is of the utmost importance. This article discusses the most common defects associated with the nail unit and its surrounding tissue, as well as the differential diagnosis and treatment of these conditions.

Onycholemmal carcinoma

A 70-year-old Japanese man presented with a 5-year history of refractory indolent onycholysis of the little finger of the right hand. Roentgenograms did not show involvement of the bone. Histological examination revealed an epithelial tumor consisting of lobular masses varying in size. The tumor was composed of keratinocytes varying in atypicality and showed infiltrative growth into the dermis but not into the phalangeal bone. The tumor had cystic structures composed of eosinophilic amorphous keratin and a surrounding thin layer of keratinocytes. Characteristically, the epithelium in the center of the tumor abruptly changed into amorphous keratin without the formation of intervening keratohyaline granules. From these findings, the mass was diagnosed as onycholemmal carcinoma. Immunohistochemically, the tumor showed a keratin profile comparable to that of the nail bed epithelium and a smaller number of Ki-67-positive proliferating tumor cells compared with those of a previous case of onycholemmal carcinoma.

Squamous cell carcinoma of the hand masquerading as a cutaneous infection

SUMMARY A 33-year-old male concreter presented with a small abscess on his right index finger following an injury at work. Histological examination of the lesion was consistent with chronic inflammation and Staphylococcus aureus, Streptococcus anginosus and Escherichia coli were isolated on cultures. The lesion was treated as a chronic fungal infection with bacterial superinfection. Seventeen months later, a bone scan showed periarticular involvement, and a diagnostic biopsy identified a well-differentiated squamous cell carcinoma. He underwent amputation of his index and middle fingers. After 4 years of follow up, there has been no evidence of recurrence at the primary site, but he has since developed two further primary squamous cell carcinomas. This case emphasizes the importance of considering malignancy when dealing with chronic infections of the hand.

Subungual Bowen's disease treated by topical aminolevulinic acid—photodynamic therapy

A 66-year-old man presented with an 18-month history of progressive nail dystrophy involving his left index finger. A diagnostic biopsy specimen confirmed the clinical suggestion of subungual Bowen's disease (carcinoma in situ). Various treatment options were considered, and the decision was made to treat with photodynamic therapy using topical 5-aminolevulunic acid administered as two treatments 4 weeks apart. The patient was reviewed 3 months after treatment and then regularly at 6-month intervals. Thirty months after treatment there remained no clinical evidence of recurrence of the condition with preservation of a normal nail unit. Although the successful treatment of cutaneous Bowen's disease with photodynamic therapy is well documented, this is the first report of the successful treatment of subungual Bowen's disease using topical aminolevulunic acid-photodynamic therapy.

Premalignant and early squamous cell carcinoma

Actinic keratosis (AK) is a common sun-induced precancerous neoplasm confined to the epidermis. The AK is the initial manifestation of a continuum of clinical and histologic abnormalities that progresses to invasive squamous cell carcinoma (SCC). Bowen's disease, also known as squamous cell carcinoma in situ, represents early SCC confined to the epidermis. More than half of all SCCs contain p53 tumor suppressor gene mutations. Like SCCs, the vast majority of AKs and Bowen's disease lesions are asymptomatic. Each AK and suspicious lesion should be treated before it progresses to invasive SCC. Destructive modalities, such as cryosurgery using liquid nitrogen and electrodesiccation and curettage, usually performed by a dermatologist, are the mainstays of therapy.

Squamous cell carcinoma of the nail bed: three case reports

Squamous cell carcinoma of the nail bed is rare, and the disease is often misdiagnosed as a benign condition. Digital amputation is often performed because of the delay in diagnosis and the involvement of the distal phalanx. Between March 1999 and March 2002, 3 patients presented to the Pamela Youde Nethersole Eastern Hospital, Hong Kong, with squamous cell carcinoma of the nail bed. Two of the patients underwent a digit-salvaging procedure-namely, wide local excision and flap coverage-and their functional outcome was satisfactory. The remaining patient received partial amputation of the thumb without significant functional loss. A high degree of suspicion is thus needed to detect squamous cell carcinoma of the nail bed; a biopsy of chronic recurrent nail bed lesions should be performed.

Onycholemmal Carcinoma

We report on a slowly growing malignant tumor of the nail bed epithelium in a 69-year-old male. On light microscopic examination, the tumor was composed of: (1) some small cysts filled with eosinophilic, amorphous keratin and lined by an atypical squamous epithelium devoid of a granular layer and (2) solid nests and strands of atypical keratinocytes filling the dermis and penetrating the phalangeal bone. Because the nail bed epithelium is comparable to the outer root sheath, or trichilemma of the hair follicle, and since the reported tumor showed some analogies with trichilemmal carcinoma, we suggest that this entity be designated 'onycholemmal carcinoma'. Disarticulation of the involved phalanx was performed and neither local recurrence nor distant metastasis was observed during 4 years of follow up.

Dermatitis-like squamous cell carcinoma

A 78-year-old man with a 2-year history of a large dermatitis-like plaque of his thigh is described. It had a raised elevated border, resembling persistent fungal dermatitis (tinea corporis). However, it proved to be a squamous cell carcinoma, prompting this description and a reminder that skin cancer may mimic dermatitis.

Subungual Squamous Cell Carcinoma of the Toe: Report on Three Cases

BACKGROUND

Primary subungual squamous cell carcinoma (SCC) of the toe is seldom reported in the literature, with most described cases occurring on the fingernails.

OBJECTIVE

To describe the clinical, histopathologic, and laboratory findings of cases of invasive subungual SCC of the toe.

METHODS

All cases of SCC of the toes retrieved from our database in the last 3 years were reviewed. A search for human papillomavirus (HPV) DNA from paraffin-embedded sections was performed with polymerase chain reaction.

RESULTS

Three patients, all male, with a subungual SCC (two well differentiated and one poorly differentiated) of the toe were identified. Treatment consisted of surgical amputation in all cases. One patient with poorly differentiated SCC and lymph node metastases also underwent inguinal lymphadenectomy. Polymerase chain reaction search for HPV DNA was negative in all samples.

CONCLUSIONS

Unlike Bowen's disease and SCC of the fingernails, a causative role of HPV infection in the development of in situ and invasive subungual SCC of the toe seems unlikely.

Human papillomavirus-associated digital squamous cell carcinoma: literature review and report of 21 new cases

OBJECTIVE

Our aim was to review the clinical behavior of human papillomavirus (HPV)-associated digital squamous cell carcinoma (SCC). Specifically, we examined evidence for the tumor's (1) infectious origin and spread, (2) response to therapy, and (3) prognosis and metastatic risk.

DESIGN

We reviewed and performed data tabulation of all 51 reported cases in the English-language literature and a case series of 23 cases (21 of them not previously reported). We present 2 of the cases in depth.

SETTING

We used previously reported cases from MEDLINE and a case series from a single dermatologic operation practice from 1985 to 1999.

RESULTS

(1) Of all cases, 10% (7/72) had an antecedent genital dysplasia or carcinoma containing the same HPV subtype as the digital SCC. (2) The rate of recurrence after general surgical therapy was 43% (6/14). After Mohs micrographic surgery the recurrence rate was 13% (2/16) for the cases in the literature, and 26% (6/23) for our case series. (3) Of tumors, 3% (2/72) have been observed to metastasize.

CONCLUSIONS

(1) This suggests the possibility of genital-digital spread as a mechanism of tumor genesis. (2) HPV-associated digital SCC is more likely to recur after surgical treatment than previously reported. This rate of recurrence greatly exceeds that for cutaneous SCCs in general and may be caused by residual postsurgical HPV. (3) The rate of metastasis, however, appears to be low.

Radiation therapy for the salvage of unresectable subungual squamous cell carcinoma

BACKGROUND

A case of subungual squamous cell carcinoma, which is a rare malignancy and has an elusive etiology, is reported.

OBJECTIVE

To present radiation therapy as a viable treatment option to amputation for surgically unresectable subungual squamous cell cancer.

METHODS

A 69-year-old man with a 16-year-old history of subungual squamous cell carcinoma of the left thumb was treated by external beam radiation therapy. In this case, bone invasion precluded the patient from successfully completing Moh's micrographic surgery.

RESULTS

The treated thumb at 17 months after radiation therapy remained tumor free.

CONCLUSION

Radiation therapy should be considered a treatment option for nail bed squamous cell carcinoma before considering amputation and perhaps as salvage for all unresectable lesions.

Gouty tophi: a squamous cell carcinoma mimicker?

BACKGROUND

Digital lesions can have a broad differential diagnosis. Squamous cell carcinoma (SCC), the most common digital malignant neoplasm, must be excluded as the cause of persistent digital lesions causing nail dystrophy.

OBJECTIVE

To describe a patient with a periungual hyperkeratotic lesion on the left fifth digit which, upon initial dermatopathologic examination, appeared to be a malignancy. However, on further biopsy, the lesion proved to be a gouty tophus.

METHODS

Case report and literature review.

RESULTS

An 84-year-old white man presented with a hyperkeratotic papule on the lateral proximal nail fold of the left fifth digit, which resulted in nail dystrophy for 1 year. Similar lesions were present on several other digits which did not affect the nail plate. Initial biopsy was consistent with actinic keratosis and was treated with cryotherapy. When the lesion persisted, repeat biopsy was performed, demonstrating fragments of squamous epithelium with focal atypia and an infiltrative growth pattern. SCC could not be excluded and the patient was referred for Mohs micrographic surgery (MMS) consultation. An excisional biopsy was performed and a white chalky material was observed at the base of the defect. Histopathology confirmed a gouty tophus. The patient was referred to his primary care physician and was treated with allopurinol.

CONCLUSION

This is the first report of gouty tophus of the periungual region presenting as a hyperkeratotic lesion. Initial clinical diagnosis favored SCC and histologic evidence suggested a possible early SCC. This lesion can be confused with digital squamous cell carcinoma. The presence of pseu- docarcinomatous hyperplasia may complicate accurate diagnosis.

Mucosal human papillomavirus types in squamous cell carcinomas of the uterine cervix and subsequently on fingers

Human papillomavirus (HPV), especially type 16, is causally involved in the pathogenesis of anogenital cancer. There is an increasing number of reports of HPV infections in squamous cell carcinoma (SCC) of the fingers. A search of the Swedish cancer register covering the period 1958-94 inclusive for women with a history of genital and upper extremity SCC revealed 63 cases. Archival material from both cervical and cutaneous lesions was traced and analysed for the presence of HPV DNA in 32 of these patients. A newly developed 'neighbour primer' polymerase chain reaction (PCR) for HPV 16 DNA, aimed at overcoming the obstacle of cross-linked target DNA, was shown to be superior to conventional general and type-specific HPV PCR tests. HPV DNA was significantly more frequently found in digital tumours than in tumours at other cutaneous sites of the upper extremities [67% (10 of 15) vs. 7% (three of 43); P < 0.001]. Among 13 patients with a history of both cervical and finger SCC, HPV 16 was found in cervical samples from seven patients. From five of these seven patients, HPV 16 was also present in the corresponding finger lesions. The results support the hypothesis of a possible transmission of patients' genital HPV infections to fingers.