What's hot?
What's hot
June 28, 2018
In this monthly column, members of the Dermatology World Editorial Advisory Workgroup identify exciting news from across the specialty.
Mallory Abate, MD
“SPF 30 or higher” is the classic, impulse response that we often give when asked about sunscreen recommendations. However, a recent study demonstrates proven benefit with higher SPF (J Am Acad Dermatol. 2018;78:902-10). A total of 199 skiers in Vail, Colorado participated in the randomized, double-blind, split-face study. Each skier wore both SPF 50+ and SPF 100+ throughout the day and was then blindly evaluated the next day for sunburn erythema. SPF 100+ was found to be significantly more effective in protecting against sunburn than SPF 50+. Why the benefit? Most consumers apply only half of the recommended amount of sunscreen and thus in actuality receive less SPF than on the label. In this way, higher SPFs likely compensate for what is lost in real-world application.
So, is higher SPF always better? The answer is not so simple. The standard set by the U.S. FDA for sunscreen labels is less stringent than that of Europe, and neither SPF (a primary measure of UVB) nor “broad-spectrum” status (achieved by meeting a critical wavelength of 370 nm) ensure adequate UVA protection for the U.S. consumer. A 2017 study found that only 55% of U.S. sunscreens met European standards for adequate UVA protection and higher SPF did not correlate with improved UVA protection (J Am Acad Dermatol 2017;77(1):42-47).
Thus, higher SPF does appear to be beneficial, particularly in terms of UVB-induced sunburn erythema. However, access to new UVA filters and better labeling standards are needed in the U.S. in order to produce the ideal sunscreen.
Rosalie Elenitsas, MD
Do you think that your pathologist can confuse lupus erythematosus and an atypical lymphoid infiltrate? It sounds crazy, but this problem may be more common than you realize. The differential diagnosis of lupus erythematosus and cutaneous lymphoma may bring to mind the problem of differentiating lupus panniculitis and subcutaneous panniculitic T cell lymphoma, or possibly tumid lupus erythematosus and cutaneous marginal zone lymphoma. These differentials have been well described in the literature, however it is little known that discoid lupus erythematosus and subacute cutaneous lupus erythematosus can also show findings that resemble cutaneous lymphoma. A recent paper by Lorenzo Cerroni’s group (Am J Dermatopathol. 2018;40:247-253) described 15 cases of cutaneous lupus erythematosus (not tumid or panniculitic types) that either mimicked lymphoma or were misdiagnosed as an atypical lymphoid process. All cases had known lupus in other lesions. In their case series, they found that the lupus could be misconstrued as marginal zone lymphoma, angiocentric lymphoma, cutaneous lymphoid hyperplasia, or mycosis fungoides. These cases could have a nodular, lichenoid, or angiocentric pattern, as well as cytological atypia of lymphocytes. Features that proved helpful in confirming the diagnosis included: interface dermatitis, clusters of CD123(+) plasmacytoid dentdritic cells, or mucin deposition. As a dermatologist, it is important to recognize this differential diagnosis. In cases where there is clinicopathologic disparity, taking multiple samples and asking your pathologist to do additional special stains or T cell gene rearrangement studies may be beneficial in confirming a diagnosis.
Simon Ritchie, MD
Although shave biopsies of suspected BCCs are intended to be diagnostic only, it is common that pathologists will comment on the margin status. This could lead to confusion, as the phrase “negative in the sections examined” could imply that the lesion was entirely excised. Prior studies have shown that only 1-2% of the margin of a biopsy specimen is assessed with standard processing, so it is possible that the margin status of these few sections are not representative of the whole. In an article in press with JAAD, Willardson, et al identified 134 biopsies diagnosed as basal cell carcinoma with negative margins and then sectioned the corresponding excision blocks at a 150 micrometer interval until either residual disease was found or until it was exhausted (doi: 10.1016/j.jaad.2017.12.071). They found that BCC biopsies with negative margins had residual disease in the excision block 24% of the time. In 91% of the cases the residual disease found was of the superficial subtype. There are two main implications of this article: margin status of BCC biopsies is not predictive of true margin status and therefore these lesions should be treated. Secondly, when presented with this pathology result a clinician could consider topical therapy or ED&C if the lesion is in a difficult anatomic location and if the entirety of the visualized lesion was biopsied initially.
Kenneth A. Katz, MD, MSc, MSCE
An ounce of prevention is worth a pound of cure. Who’s measuring? For clinical preventive services in the United States, that task largely falls to the U.S. Preventive Services Task Force (USPSTF), a volunteer panel of national experts in prevention and evidence-based medicine. Importantly, USPSTF recommendations bearing Grade “A” or “B” must be covered by insurance without co-payments.
In March 2018 USPSTF released updated recommendations, for persons without a skin cancer history, on behavioral counseling for skin cancer prevention and screening for skin cancer with skin self-examination, as follows:
- Young adults (through age 24), adolescents, children, and parents of young children with fair skin type: Counsel about minimizing UV radiation exposure (Grade “B”: provide this service).
- Adults older than 24 years with fair skin type: Selectively offer counseling about minimizing exposure to UV radiation (Grade “C”: selectively counsel based on professional judgment and patient preferences).
- Self-skin examination in adults: No recommendation (Grade “I”; evidence insufficient to assess balance of benefits and harms).
This updated recommendation expands the age range for behavioral counseling and maintains the Grade “I” recommendation, from 2009, for skin self-examination.
CDR Josephine Nguyen, MD, HCDS
There is accumulating evidence of the significant associations between rosacea and systemic comorbidities. Haber et al (J Am Acad Dermatol. 2018 Apr;78(4):786-792.e8) conducted a systematic literature review of 29 studies and found a statistically significant relationship between rosacea and depression, hypertension, cardiovascular disease, anxiety disorder, diabetes mellitus, migraine, rheumatoid arthritis, Helicobacter pylori infection, ulcerative colitis, and dementia. The review suggests a possible correlation between the severity of rosacea and the incidence of comorbidities and that the chronic inflammation seen in rosacea can be systemic.
How does that impact your patient care? Optimal care would include assessing patients for cardiovascular risk factors as well as GI and psychiatric morbidity, especially in patients with more severe disease. Recent data showed a decreased risk of vascular events in rosacea patients treated with tetracycline. It is thought the anti-inflammatory properties of tetracyclines led to beneficial effects on the cardiovascular system. Examples of CVD screening questions would include screening for personal and family history of CVD, calculating BMI, checking blood pressure, running a fasting lipid panel and fasting glucose of HbA1C; and suggesting aspirin or low-dose doxycycline in patients with several risk factors.
Sylvia Hsu, MD
Lab monitoring and ophthalmologic exams during hydroxychloroquine therapy: too much, too often? According to American College of Rheumatology guidelines (Arthritis Rheumatol. 2016;68(1):1-26), no laboratory monitoring is recommended for patients taking hydroxychloroquine after baseline labs. An American Academy of Ophthalmology statement (Ophthalmology. 2016;123:1386-1394) recommends a baseline fundus examination in the first year of therapy. If the baseline exam is normal, no ophthalmologic exam is needed for the next 5 years for patients on acceptable doses without risk factors (liver disease, age > 60 years). Daily dosage should be <5 mg/kg actual weight; previous recommendations to use ideal body weight for dose calculation resulted in over-dosage in thin individuals.
There are no comparable data for chloroquine toxicity. The mechanisms of action are presumed to be similar for both drugs, and older literature equated 3 mg of chloroquine with 6.5 mg of hydroxychloroquine. With this estimation, the equivalent of 5 mg/kg hydroxychloroqine would be 2.3 mg/kg chloroquine. Many reports suggest that chloroquine is somewhat more toxic than hydroxychloroquine, but there are no good data on pharmacologic equivalence. The higher toxicity of chloroquine may be an artifact of prescription practices, which have been biased by the tablet size (250 mg). Almost any patient taking 1 tablet of chloroquine will receive more than 2.3 mg/kg.
Because hydroxychloroquine is available in 200 mg tablets and chloroquine is available in 250 mg tablets, it may seem difficult to prescribe intermediate doses. However, blood levels of these drugs stabilize over many weeks, so variable dosing will average out over time. Intermediate doses can be obtained by splitting tablets or by skipping a tablet on certain days of the week.
