Zoon plasma cell balanitis is a benign idiopathic inflammatory skin disease of the glans penis, the coronal sulcus, and the inner aspect of the prepuce. Clinically, reddish-brown sharply demarcated patches are observed, but the presentation may be equivocal, and biopsy is often necessary to exclude a malignant diagnosis. In this observer-blinded study, Arzberger et al demonstrate that reflectance confocal microscopy allowed differentiation between balanitis and carcinoma in situ. This technology may help to avoid biopsies at this sensitive site.
As smartphone use increases, these devices are applied to functions beyond communication and entertainment and often become tools that are involved intimately in many aspects of daily life through the use of specialized applications. In this case-control diagnostic accuracy study, Wolf et al demonstrate that the performance of smartphone applications in assessing melanoma risk is highly variable, and that 3 of 4 smartphone applications incorrectly classified 30% or more of melanomas as unconcerning. Reliance on these applications, which are not subject to regulatory oversight, in lieu of medical consultation can dangerously delay the diagnosis of melanoma.
Desmoplastic melanoma (DM) is a rare variant of melanoma, making up less than 4% of all melanomas. It is not uncommon for the definitive diagnosis of DM to be delayed because of a relatively benign appearance and difficulties in its initial clinical recognition. Although dermoscopy has been shown to increase diagnostic accuracy for most melanoma subtypes, there are limited data regarding its role in the diagnosis of DM. In this retrospective case series of 37 DM cases, Jaimes et al describe the dermoscopic clues observed in DM, including atypical vascular structures, peppering, and occasionally other melanoma-specific structures.
While the overall prognosis of cutaneous squamous cell carcinoma (CSCC) is excellent, a subset of tumors do recur, metastasize, and cause death. Tumor characteristics associated with poor outcomes have been reported in a few case series. In this retrospective cohort study, Jambusaria-Pahlajani et al demonstrate that the bulk of poor outcomes occurred in AJCC stage T2 cases. Four risk factors were found to be statistically independent prognostic factors: poor differentiation, perineural invasion, tumor diameter greater than 2 cm, and invasion beyond subcutaneous fat. These factors were incorporated into an alternative staging system that may offer improved prognostic discrimination among stage T2 tumors.
The most common cause of skin and soft-tissue infections in the United States is Staphylococcus aureus. Methicillin-resistant S aureus (MRSA) accounts for more than 50% of community acquired S aureus infections in many US centers. In this retrospective observation, Zabielinski et al demonstrate that the relative proportion of MRSA rose by 17% over a 3-year period, with an overall proportion of 35.7%. In addition, an increasing sensitivity to ciprofloxacin was noted, emphasizing the importance of obtaining cultures of infected sites before administering an antibiotic and of tailoring therapy to antibiogram results as soon as possible.
In This Issue of JAMA Dermatology. JAMA Dermatol. 2013;149(4):395. doi:10.1001/jamadermatol.2013.10