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.
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.
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.
The symptoms and clinical appearances of allergic contact dermatitis and irritant contact dermatitis are similar in the occluded peristomal environment and are therefore difficult to distinguish on clinical grounds alone. Allergy is a relatively infrequent cause of peristomal dermatitis despite the continual exposure of skin to the components of cleansers, medicaments, other accessories and the stoma bag systems themselves.
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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.