Rapid ex vivo examination of Mohs specimens using optical coherence tomography

BACKGROUND

Mohs micrographic surgery (MMS) is an effective treatment for certain non-melanoma skin cancers. Optical coherence tomography (OCT) is a biomedical imaging modality that permits high-resolution imaging of the epidermis and dermis with the potential to detect both healthy tissue and tumour. OCT may also provide a means of detecting and differentiating between the various histological subtypes of basal cell carcinomas (BCC) in vivo.

OBJECTIVE

The aim of this prospective ex vivo study was to evaluate the efficacy of OCT in recognising healthy and pathological margins of excised BCC lesions and detecting different BCC subtypes.

METHODS

Seventy-three subjects with biopsy-proven BCCs on the facial region undergoing MMS were recruited. Narrow clinically healthy margins of the skin surrounding the tumour were included in the excisional biopsy. Biopsies were scanned with the OCT instrument immediately ex vivo and processed to obtain horizontal Mohs frozen sections and compared with their corresponding OCT images.

RESULTS

Histopathological analysis of 280 margins showed 232 tumour free margins and 48 tumour-involved margins. OCT showed very good sensitivity (81.2%) and specificity (94.3%) in detecting healthy from tumour-involved margins. OCT accuracy was 93.4%, and the intra- and inter-observer reliability was substantial (Kappa value ranged between 0.63-0.76).

CONCLUSION

This study shows the accuracy of ex vivo OCT in identifying the margin status of BCCs of the head and neck region. Moreover, this modality has demonstrated good capability in distinguishing different BCC subtypes and the potential for in vivo in situ diagnostics.

Expression of DNA mismatch repair proteins and MSH2 polymorphisms in nonmelanoma skin cancers of organ transplant recipients

BACKGROUND

Organ transplant recipients (OTRs) have an increased risk of skin cancer. Treatment with azathioprine, commonly used in post-transplant immunosuppressive regimens, results in incorporation of 6-thioguanine (6-TG) into DNA. Mismatch repair (MMR)-defective cells are resistant to killing by 6-TG. Azathioprine exposure confers a survival advantage on MMR-defective cells, which are hypermutable and may therefore contribute to azathioprine-related nonmelanoma skin cancer, a phenomenon we have previously demonstrated in transplant-associated sebaceous carcinomas. The MSH2 protein is an important component of DNA MMR. The -6 exon 13 T>C MSH2 polymorphism is associated with impaired MMR, drug resistance and certain cancers.

OBJECTIVES

To investigate (i) whether loss of MMR protein expression and microsatellite instability are over-represented in squamous cell carcinomas (SCCs) from OTRs on azathioprine compared with SCCs from immunocompetent patients, and (ii) whether the MSH2 -6 exon 13 polymorphism is over-represented in OTRs with skin cancer on azathioprine.

METHODS

(i) Immunohistochemical staining was used to assess expression of the MMR proteins MSH2 and MLH1 in cutaneous SCCs from OTRs on azathioprine and from immunocompetent patients. (ii) Blood samples from OTRs on azathioprine with and without skin cancer were genotyped for the -6 exon 13 MSH2 polymorphism.

RESULTS

(i) MSH2 and MLH1 protein expression was not altered in SCCs from OTRs on azathioprine and there was no difference in expression between SCCs from OTRs and immunocompetent patients. (ii) There was no association between MSH2 polymorphism genotype frequency and OTR skin cancer status.

CONCLUSIONS

Despite previous findings in transplant-associated sebaceous carcinomas, defective MMR and the -6 exon 13 MSH2 polymorphism are unlikely to play a significant role in the development of SCC in OTRs on azathioprine.

Treatment of post-transplant premalignant skin disease: a randomized intrapatient comparative study of 5-fluorouracil cream and topical photodynamic therapy

BACKGROUND

Organ transplant recipients (OTR) are at high risk of developing nonmelanoma skin cancer and premalignant epidermal dysplasia (carcinoma in situ/ Bowen's disease and actinic keratoses). Epidermal dysplasia is often widespread and there are few comparative studies of available treatments.

OBJECTIVES

To compare topical methylaminolaevulinate (MAL) photodynamic therapy (PDT) with topical 5% fluorouracil (5-FU) cream in the treatment of post-transplant epidermal dysplasia.

METHODS

Eight OTRs with epidermal dysplasia were recruited to an open-label, single-centre, randomized, intrapatient comparative study. Treatment with two cycles of topical MAL PDT 1 week apart was randomly assigned to one area of epidermal dysplasia, and 5-FU cream was applied twice daily for 3 weeks to a clinically and histologically comparable area. Patients were reviewed at 1, 3 and 6 months after treatment. The main outcome measures were complete resolution rate (CRR), overall reduction in lesional area, treatment-associated pain and erythema, cosmetic outcome and global patient preference.

RESULTS

At all time points evaluated after completion of treatment, PDT was more effective than 5-FU in achieving complete resolution: eight of nine lesional areas cleared with PDT (CRR 89%, 95% CI: 0.52-0.99), compared with one of nine lesional areas treated with 5-FU (CRR 11%, 95% CI: 0.003-0.48) (P = 0.02). The mean lesional area reduction was also proportionately greater with PDT than with 5-FU (100% vs. 79% respectively). Cosmetic outcome and patient preference were also superior in the PDT-treated group.

CONCLUSIONS

Compared with topical 5-FU, MAL PDT was a more effective and cosmetically acceptable treatment for epidermal dysplasia in OTRs and was preferred by patients. Further studies are now required to confirm these results and to examine the effect of treating epidermal dysplasia with PDT on subsequent development of squamous cell carcinoma in this high risk population.

Vulval intraepithelial neoplasia and periungual Bowen's disease concordant for mucosal (HPV-34) and epidermodysplasia verruciformis (HPV-21) human papillomavirus types

Human papillomavirus (HPV) infection is associated with genital malignancy and specific cutaneous malignancies. We report a case of an HPV-associated concurrent vulval intraepithelial neoplasia and periungual Bowen's disease in a young immunocompetent Afro-Caribbean woman with no known risk factors for either disease. HPV genotyping studies detected multiple alpha and beta papillomaviruses with concordance for HPV-34 [a high-risk (HR) mucosal type], and HPV-21 [an epidermodyslasia verruciformis (EV) type] in both vulval and finger tissue. Although the HR-mucosal viruses detected are likely to have a pathogenic role in vulval intraepithelial neoplasia, this is the first report of concordance for EV HPV types in both genital and nongenital skin premalignancies. This case, in the context of accumulating epidemiological and experimental data in cutaneous SCC, raises the question of whether EV HPV may contribute to vulval malignancy, and further study is merited.

Primary cutaneous B-cell lymphoma associated with actinic prurigo

We describe two patients with a diagnosis of actinic prurigo who subsequently developed cutaneous B-cell lymphoma. This is the first report, to our knowledge, of this association. We propose that chronic antigenic stimulation by ultraviolet radiation, in the context of actinic prurigo, may have been causal in the development of these unusual lymphomas.

Imiquimod cream 5% for recalcitrant cutaneous warts in immunosuppressed individuals

BACKGROUND

Viral warts may cause significant morbidity in individuals unable to mount an adequate T-helper 1 cell-mediated immune response to human papillomavirus. Imiquimod is a potent inducer of antiviral cytokine activity which has shown significant efficacy in the treatment of genital warts. Similar efficacy in cutaneous warts is not yet established.

OBJECTIVES

To assess the response of persistent cutaneous warts to 5% imiquimod cream in immunosuppressed individuals.

METHODS

Fifteen immunosuppressed patients with warts on the hands and/or feet present for more than 18 months, which had failed to respond to a minimum of 12 weeks of topical salicylic acid and four cycles of cryotherapy, were recruited. Imiquimod 5% cream was applied in an open label, right vs. left comparison study for 24 weeks (three times weekly for 8 weeks, daily for 8 weeks, then daily with occlusion for 8 weeks).

RESULTS

Twelve (80%) patients completed the study protocol. Benefit was seen in five patients [36% in the intent-to-treat analysis (14 patients)], including more than 30% clearance of warts in three patients and reduction in overall size of warts in two further cases. Local skin reactions occurred in four (29%) patients and were usually mild. A transient rise in creatinine (11-29% above baseline) was measured in three renal transplant recipients, but we did not consider that this was related to imiquimod exposure.

CONCLUSIONS

This is the first controlled study to assess therapeutic efficacy of topical 5% imiquimod cream in persistent warts associated with immunosuppression. It provides preliminary evidence that topical imiquimod may benefit a subgroup of immunosuppressed patients with recalcitrant cutaneous warts.

Etanercept-induced systemic lupus erythematosus

Tumour necrosis factor (TNF) is a pro-inflammatory cytokine with a role in the pathogenesis of a number of conditions including rheumatoid arthritis, psoriasis, psoriatic arthritis, ankylosing spondylitis and Crohn's disease. Etanercept (Enbrel; Immunex Corp., Seattle, WA, USA) is a recombinant soluble fusion protein of TNF-alpha type II receptor and IgG which acts by blocking the action of TNF-alpha. It is licensed for use in rheumatoid arthritis and juvenile chronic arthritis. A number of studies report the development of antinuclear and anti-double-stranded DNA antibodies in patients treated with TNF antagonists for rheumatoid arthritis. There are few reports of the development of clinical features of discoid, subacute or systemic lupus erythematosus. We present one of the first reported cases of etenercept-induced systemic lupus erythematosus and review the literature of lupus and TNF antagonists.

Cyclosporin in childhood psoriasis

BACKGROUND

Cyclosporin is known to be highly effective in the treatment of psoriasis in adults. It has also proved effective and well tolerated in the treatment of severe childhood atopic dermatitis. Psoriasis in childhood is relatively unusual but by no means rare and on occasions the disease can be very difficult to control in this age group. The use of cyclosporin for psoriasis in childhood has received scarcely any attention and in the few cases that have been reported the results have been inconsistent. Three children aged from 7 to 11 years with severe psoriasis resistant to topical agents were treated with cyclosporin. The highest dose required was 3.5 mg/kg per day. The duration of treatment ranged from 6 weeks to 4 months. Cyclosporin was effective and generally well tolerated. Treatment was interrupted in one case due to nausea and diarrhoea. None of the patients developed hypertension or renal impairment. The potential role of cyclosporin in severe childhood psoriasis is discussed.

Cyclosporin in childhood psoriasis

BACKGROUND

Cyclosporin is known to be highly effective in the treatment of psoriasis in adults. It has also proved effective and well tolerated in the treatment of severe childhood atopic dermatitis. Psoriasis in childhood is relatively unusual but by no means rare and on occasions the disease can be very difficult to control in this age group. The use of cyclosporin for psoriasis in childhood has received scarcely any attention and in the few cases that have been reported the results have been inconsistent. Three children aged from 7 to 11 years with severe psoriasis resistant to topical agents were treated with cyclosporin. The highest dose required was 3.5 mg/kg per day. The duration of treatment ranged from 6 weeks to 4 months. Cyclosporin was effective and generally well tolerated. Treatment was interrupted in one case due to nausea and diarrhoea. None of the patients developed hypertension or renal impairment. The potential role of cyclosporin in severe childhood psoriasis is discussed.

Tea tree oil dermatitis associated with linear IgA disease

Tea tree oil dermatitis is an increasingly common finding, reflecting the strong demand for natural remedies and aromatic substances. Linear immunoglobulin A (IgA) disease is a rare acquired subepidermal blistering disorder, characterized by basement membrane zone IgA deposition. We describe a patient in whom linear IgA disease appears to have been precipitated by a contact reaction to tea tree oil.