Up to 60% of squamous cell carcinomas (SCCs) are thought to arise from preexisting actinic keratoses (AKs); and destruction of AKs has become one of the most common dermatologic office procedures. The current standard of care for AKs involves routine skin surveillance and destruction of lesions with liquid nitrogen cryotherapy, often in combination with prescribed topical agents to augment the response. Hantash et al demonstrate that facial skin resurfacing regimens worked as well as conventional 5% fluorouracil topical therapy in preventing or delaying the occurrence of AKs and nonmelanoma skin cancers in patients with substantial actinic damage. These data suggest that 1-time facial resurfacing provides sufficient cutaneous malignancy prophylaxis to reduce the need for frequent and multiple destructive procedures.
Topical anesthetics can be applied painlessly and can provide sufficient pain control to maintain patient comfort throughout a variety of laser procedures. Although the use of topical lidocaine is considered relatively safe, instances of cardiotoxic and neurotoxic adverse events have been reported. Marra et al describe a 52-year-old woman undergoing fractional photothermolysis with prolonged exposure to 30% lidocaine gel who developed symptomatic lidocaine toxicity. Laser surgeons should be aware of this phenomenon, particularly in patients with underlying hepatic, endocrine, cardiac, or central nervous system dysfunction, or in those who take drugs that interfere with hepatic lidocaine metabolism.
Distinguishing benign melanocytic nevi from malignant melanomas can present a diagnostic challenge to the dermatologist. The precise origins of melanomas remain unclear. Although atypical nevi are thought to be precursor lesions in some cases, the transition point of a nevus to a melanoma is not well characterized. Perry et al compared 2 human melanoma cell lines derived from radial growth phase and vertical growth phase melanomas. Among the factors differentially expressed in a protein array, Wilms Tumor 1 (WT1) was much more highly expressed in the vertical growth melanoma cells. In addition, WT1 staining of paraffin-embedded samples demonstrated far more frequent WT1 staining in melanomas than in nevi. These data suggest that immunohistochemical analysis for WT1 may be a useful and readily available application for differentiating dysplastic nevi from malignant melanomas.
Muir-Torre syndrome (MTS) is an autosomal dominant genodermatosis characterized by the association of sebaceous skin tumors and internal malignancy, most commonly colon cancer. Early identification of the skin lesions of MTS allows improved surveillance of these patients because the skin lesions often precede the internal neoplasms. In this case report, Marazza et al describe a 54-year-old man with sebaceous adenomas. A workup revealed sessile polyps in the sigmoid colon with low- to high-grade zones of dysplasia. Immunohistochemical testing for MSH-2, MSH-6, and MLH-1 allowed rapid identification of an underlying mismatch repair defect and early diagnosis of MTS.
In this clinical presentation of sebaceous adenomas, several erythematous papules show an irregular and ulcerated surface. The central lesion presents a rolled and pearly margin resembling a keratoacanthoma and a basal cell carcinoma in the differential diagnosis.
Acitretin is the only oral retinoid approved for the treatment of psoriasis. Skeletal hyperostosis represents a rare potential adverse effect with long-term use, and acitretin is teratogenic. However, this agent carries none of the cumulative toxic effects seen with other systemic psoriasis agents. In this retrospective trial, Pearce et al demonstrate the effectiveness of low-dose (25-mg/d) acitretin for use in some patients with psoriasis as a means of reducing the risk of common clinical and laboratory adverse events without sacrificing long-term effectiveness.
This Month in Archives of Dermatology. Arch Dermatol. 2006;142(8):969. doi:10.1001/archderm.142.8.969