Lucy L. Chen

Clinical and Dermoscopic Characteristics of Desmoplastic Melanomas

OBJECTIVE To describe and analyze the clinical and dermoscopic characteristics of desmoplastic melanoma (DM) as a function of pathologic subtype and phenotypic traits. DESIGN Retrospective case series. SETTING Eight high-risk dermatology clinics. PATIENTS Patients with DM confirmed by histopathologic analysis whose records included a high-quality dermoscopic image. MAIN OUTCOME MEASURES Clinical, dermoscopic, and histopathologic features of DM. RESULTS A total of 37 DM cases were identified. The majority of patients had fair skin, few nevi, and no history of melanoma. Lentigo maligna was the most frequent subtype of melanoma associated with DM. The most frequent clinical presentation of DM was a palpable and/or indurated lesion located on sun-exposed skin. Forty-three percent of cases were classified as pure DM, and 57% as mixed DM. Pure DM lesions were thicker than mixed DM lesions (4.10 vs 2.83 mm) (P = .22) and were less likely to have an associated epidermal non-DM component (63% vs 100%) (P = .004). Dermoscopically, DMs had at least 1 melanoma-specific structure, the most frequent being atypical vascular structures. Peppering was more frequently seen in pure DM (44% in pure DM vs 24% in mixed DM) (P = .29). In contrast, crystalline structures, polymorphous vessels, and vascular blush were more commonly seen in mixed DM. CONCLUSIONS Though DM can be difficult to diagnose based on clinical morphologic characteristics alone, dermoscopy has proved to be a useful aid during the evaluation of clinically equivocal lesions or those lesions with a benign appearance. The most common dermoscopic clues observed in DMs included atypical vascular structures, peppering, and occasionally other melanoma-specific structures.

Performance of the First Step of the 2-Step Dermoscopy Algorithm

IMPORTANCE The 2-step dermoscopy algorithm aims to guide the decision-making process to biopsy or not biopsy a skin lesion by providing the most probable diagnosis via a systematic approach. OBJECTIVE To evaluate the diagnostic accuracy and potential limitations of the first step (to differentiate melanocytic from nonmelanocytic lesions) of the 2-step dermoscopy algorithm. DESIGN, SETTING, AND PARTICIPANTS Retrospective study in a clinical practice of one dermatologist of biopsy data of all skin lesions from one clinic during a 10-year period. The prebiopsy and histopathology diagnoses were classified as melanocytic or nonmelanocytic. MAIN OUTCOMES AND MEASURES The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for the first step were estimated using the histopathological lesion classifications as the standard. RESULTS The sensitivity of the first step for correctly identifying melanocytic lesions was 85%, and the specificity was 94%. Approximately 7% of all lesions (667 of 9168) had discordant classifications, with 415 (4.5%) being false-positive lesions (clinically classified as melanocytic and histopathologically classified as nonmelanocytic) and 252 (2.7%) being false negatives (clinically classified as nonmelanocytic and histopathologically classified as melanocytic). Common classification errors included intradermal nevus misclassified as basal cell carcinoma and nonmelanocytic lesions (eg, seborrheic keratosis, lichen planus-like keratosis, basal cell carcinomas) misclassified as melanocytic because they mimic melanoma. Clinically, 8 of 381 melanomas were misclassified as nonmelanocytic (primarily as pigmented basal cell carcinomas and squamous cell carcinomas). CONCLUSIONS AND RELEVANCE The 2-step dermoscopy algorithm, including its first step, has high sensitivity, specificity, and accuracy and can be relied on to provide an accurate and specific prebiopsy diagnosis and to help guide management decisions. Some lesions had a higher chance of being misclassified, with the most common being intradermal nevi. This algorithm helps toward maximizing the detection of skin cancer to ensure that malignant lesions are not missed and aims at making more precise clinical diagnoses.

Cutaneous Eruption in a U.S. Woman with Locally Acquired Zika Virus Infection

Local, autochthonous transmission of Zika virus was identified in a pregnant woman in July 2016 in southern Florida.

Vascular Features of Nail Psoriasis Using Dynamic Optical Coherence Tomography

Background: Nail psoriasis is a painful and disfiguring nail disease that often leads to invasive biopsies. Dermoscopy of the hyponychium can be useful in the diagnosis showing twisted coiled vessels. Structural features of nail psoriasis have been described with optical coherence tomography (OCT). Objectives: To investigate vascular features of nail psoriasis using dynamic OCT. Methods: This was an observational, prospective, controlled study in which psoriasis patients with psoriatic nail changes and healthy control patients underwent OCT imaging of the distal nail plate and proximal nail fold. Vertical and horizontal OCT images were analyzed to describe structural and vascular features and to quantify blood flow at depth. Results: Sixteen psoriatic nails and 16 control nails were included. Psoriatic nails had significantly increased blood flow in the proximal nail fold at depths of 0.72 mm (p = 0.035) and 0.76 mm (p = 0.027). Nail thickness was significantly greater in psoriatic nails compared to control nails (p = 0.0016). Compared to control nails, psoriatic nails had dilated, disorganized blood vessels superficially in the proximal nail fold. Limitations: The main limitation of our study is the relatively small sample size. Conclusions: OCT can identify structural and vascular features specific to nail psoriasis.

Rates of Dermoscopy Use for Melanoma Diagnosis in the Miami VA Medical Center

Author Contributions: Drs Ibrahim and Bergfeld had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Ibrahim, Piliang, Bergfeld. Acquisition, analysis, or interpretation of data: All authors. Drafting of the manuscript: Ibrahim, Bergfeld. Critical revision of the manuscript for important intellectual content: All authors. Statistical analysis: Ibrahim, Bayart. Administrative, technical, or material support: Bayart, Hogan, Piliang, Bergfeld. Study supervision: Piliang, Bergfeld.

Difficult-to-diagnose facial melanomas: Utility of reflectance confocal microscopy in uncovering the diagnosis.

LM: Lentigo maligna pAK: pigmented actinic keratosis RCM: reflectance confocal microscopy M elanoma on sun-damaged skin, commonly known as lentigo maligna (LM, akin to melanoma in situ) and lentigo maligna melanoma (akin to invasive melanoma), is mostly found on the head and neck of elderly patients. This type of melanoma, particularly when found early, may be difficult to diagnose on clinical inspection. Dermoscopy is a noninvasive imaging technique that aids in the identification of pigmented skin lesions and increases the diagnostic accuracy beyond naked eye examination. The dermoscopic criteria for facial LM were previously described. Because facial skin is characterized histopathologically by prominent adnexal openings, solar elastosis, and flattening of the dermoepidermal junction, the dermoscopic criteria of LM are distinct from those used for melanomas on the body and extremities. Moreover, the dermoscopic differentiation between facial LM and other nonmelanocytic diagnostic entities, such as pigmented actinic keratosis (pAK), solar lentigo, or lichen-planuselike keratosis can be challenging. In daily practice, when presented with a pigmented facial macule, the clinician must decide whether to biopsy the lesion and possibly leave a scar at a cosmetically sensitive site, followupwith the lesion, or treat it with nonsurgical modalities (eg, cryotherapy and topical creams). This decision may be hampered by some degree of diagnostic uncertainty. To aid in such a scenario, reflectance confocal microscopy (RCM) is a diagnostic device that uses a low-intensity laser light to produce high-resolution

Enlarging pink plaque on the trunk in a middle‐aged woman

A 37-year-old woman with no significant past medical history presented with a solitary pink lesion on her midchest that had enlarged slowly over the previous 4 years. The lesion was occasionally pruritic, without bleeding or tenderness. On physical examination, the patient demonstrated a 20 9 22-mm, centrally depressed pink plaque (Fig. 1). Dermoscopically, the lesion had prominent black follicular plugs and central telangiectatic vessels radiating towards the periphery. A full skin examination found no other lesions of similar appearance. A punch biopsy of the lesion was obtained.

Pyogenic granuloma association with isotretinoin treatment for acne

The histopathology and immunohistochemistry of the nodule were suggestive of a metastatic adenocarcinoma; therefore, a diagnosis of SMJN was rendered for the umbilical nodule. Further 18F-fluorodeoxyglucose positron emission tomography–computer tomography and a gastroscopy with a biopsy proved a gastric adenocarcinoma with metastasis to abdominal and pelvic cavities and the umbilicus. At this point, a final diagnosis of a metastatic gastric adenocarcinoma for the patient was made.