Mohs micrographic surgery for the treatment of primary cutaneous mucinous carcinoma.

Primary cutaneous mucinous carcinoma (PCMC) is a rare adnexal tumour of the skin. Clinically, it appears as a benign cyst, but it has characteristic histopathology. It is a slow-growing tumour that rarely metastasizes but is associated with significant morbidity due to its high recurrence rate. Standard practice has been to surgically remove it with a wide local excision of 1-2-cm margin. In the last decade, increasing reports of Mohs micrographic surgery (MMS) for the treatment of PCMC have been described. MMS appears to reduce recurrence rates while allowing for more conservative margins. Given the rarity of PCMC, there are no prospective randomized control trials on treatment. This is the largest case series of PCMC treated by MMS to date.

Defining the Validity of Skin Self-Examination as a Screening Test for the Detection of Suspicious Pigmented Lesions: A Meta-Analysis of Diagnostic Test Accuracy.

BACKGROUND: Skin self-examination (SSE) is widely promoted for the detection of suspicious pigmented lesions. However, determining screening accuracy is essential to appraising the usefulness of SSE. OBJECTIVES: The aim of this work was to pool estimates from studies of SSE diagnostic accuracy in the detection of suspicious pigmented lesions. METHODS: This study was registered with PROSPERO (CRD42021246356) and conducted in accordance with PRISMA-DTA guidelines. A systematic search of Medline (PubMed) EMBASE, CINAHL, and The Cochrane Library was conducted to identify relevant studies. We included studies that examined the accuracy of SSE, either whole-body or site-specific, for detecting change in individual pigmented lesions or detecting an atypical naevus. A univariate random-effects model, based on logit-transformed data, was used to calculate a summary diagnostic odds ratio (DOR) as well as pooled sensitivity and specificity. Cochran's Q test and the I2 statistic were calculated to assess heterogeneity. A proportional hazards model was used to calculate the area under the curve (AUC) and plot the summary receiver operator characteristic curve. We used the Quality Assessment of Diagnostic Accuracy Studies-2 tool to grade study quality. RESULTS: We identified 757 studies, of which 3 met inclusion criteria for quantitative synthesis. The pooled sensitivity and specificity based on 553 included participants was 59 and 82%, respectively. The summary DOR was 5.88 and the AUC was 0.71. There were some concerns regarding risk of bias in all 3 studies. CONCLUSIONS: SSE can detect suspicious pigmented lesions with reasonable sensitivity and relatively high specificity, with the AUC suggesting acceptable discriminatory ability.

Histological Features of Methylene Blue-Induced Phototoxicity Administered in the Context of Parathyroid Surgery.

Methylene blue is a chromophore dye known for its photosensitizing properties. It is also administered intravenously as a tracer in parathyroid surgery to identify abnormal glands. We describe 2 cases of acute methylene blue-induced phototoxicity in patients who underwent parathyroidectomy. Both patients developed an acute vesiculopustular inflammatory rash on the anterior neck corresponding to the site exposed intraoperatively to overhanging surgical lights. One of the patients also developed a bulla on her finger at the site of attachment of the oxygen probe. Biopsies were taken from both patients at different time points. The histological findings included destruction of sebaceous glands and deposition of diastase-periodic acid-Schiff-positive hyaline material around dermal blood vessels. These features are similar to those seen in skin treated with photodynamic therapy and systemic photosensitivity disorders such as the porphyrias. The wavelengths of light emitted by the surgical lights and oxygen probe overlap with the absorption spectrum of methylene blue. This resulted in excitation of the systemically administered methylene blue at exposed sites, with resultant local tissue damage and a phototoxic reaction.

The development and validation of a decision aid to enhance shared decision-making for the management of actinic keratosis.

Actinic keratoses (AKs) are common pre-malignant lesions. There are numerous management options including active surveillance, multiple topical therapies, cryotherapy, curettage and cautery, and photodynamic therapy, each with their own risks, benefits and efficacy. Best practice currently involves shared decision-making between patient and clinician, particularly in the setting of multiple management options. Patient decision aids have been shown to be beneficial in the shared decision-making process. In view of this, we have developed and validated a decision aid for the management of AKs, in concordance with the International Patient Decision Aids Standards.

Associations between ultraviolet radiation, basal cell carcinoma site and histology, host characteristics, and rate of development of further tumors.

BACKGROUND: Patients with basal cell carcinoma (BCC) frequently develop further tumors during follow-up. OBJECTIVE: We sought to elucidate the relative effects of pattern of ultraviolet radiation exposure, and site and histologic type of the first tumor, on the rate of increase in BCC numbers. METHODS: We used negative binomial regression analysis to study the association of selected variables on the rate of increase in BCC numbers in 266 Caucasian patients who first presented with a tumor on the head/neck or trunk with nodular or superficial histology. RESULTS: Patients with an initial truncal BCC with superficial histology demonstrated significantly faster increases in BCC numbers than did patients with other site and histology combinations. CONCLUSIONS: These data indicate that site and histology define subsets of patients with BCC.

Nonmelanoma skin cancer.

Nonmelanoma skin cancer (NMSC) represents the most common form of cancer in Caucasians, with continuing increase in incidence worldwide. Basal cell carcinoma (BCC) accounts for 75% of cases of NMSC, and squamous cell carcinoma (SCC) accounts for the remaining majority of NMSC cases. Whilst metastasis from BCC is extremely rare, metastasis from high-risk SCC may be fatal. In this article, we review the aetiology, diagnosis and management of NMSC.

Focus on Basal cell carcinoma.

Nonmelanoma skin cancers (NMSCs), which include basal and squamous cell cancers are the most common human cancers. BCCs have a relatively low metastatic rate and slow growth and are frequently underreported. Whilst there is a definite role of sunexposure in the pathogenesis of BCC, several additional complex genotypic, phenotypic and environmental factors are contributory. The high prevalence and the frequent occurrence of multiple primary BCC in affected individuals make them an important public health problem. This has led to a substantial increase in search for newer noninvasive treatments for BCC. Surgical excision with predetermined margins remains the mainstay treatment for most BCC. Of the newer non-invasive treatments only photodynamic therapy and topical imiquimod have become established in the treatment of certain BCC subtypes, while the search for other more effective and tissue salvaging therapies continues. This paper focuses on the pathogenesis and management of BCC.

Management of high-risk squamous cell carcinoma of the skin.

Cutaneous squamous cell cancer (SCC) is the second most common skin cancer, accounting for one-fifth of all cutaneous malignancies. The majority arise on the head and neck skin, and cumulative UV exposure is thought to be the most likely etiological factor. The majority of deaths from SCC occur in a high-risk subgroup of patients. This high-risk subgroup of patients can be identified as those with tumors greater than 2 cm in diameter; tumor thickness over 4 mm; moderately/poorly differentiated or desmoplastic histological SCC subtype; ear, lip, hand, feet or genital tumor site; presence of perineural or lymphovascular invasion; nodal metastasis at presentation; recurrent SCC; SCC arising from scars or chronic skin disease, for example, chronic ulcers; and SCC arising in immunosuppressed patients. It is important to identify and aggressively treat these patients, as high-risk SCC are associated with a greater mortality and morbidity. This article reviews the diagnosis and management of such high-risk SCC.