Basal cell carcinoma, blue-white variant: Dermatoscopic findings in 32 cases.

BACKGROUND: The diagnosis of basal cell carcinoma is histopathological, but there are dermatoscopic criteria that confer high sensitivity and specificity to help the clinician improve its identification. However, the basal cell carcinoma blue-white variant does not totally meet these dermatoscopic criteria, and thus can be confused with other pigmented tumors. In the literature reviewed, we found only five cases of this variant. AIMS: The present objective is to describe the dermatoscopic characteristics of the blue-white variant of basal cell carcinoma observed in a tertiary dermatology institute. METHODS: The dermatoscopy files of patients with a histopathological diagnosis of basal cell carcinoma between January 1, 2006 and December 31, 2015 were reviewed. RESULTS: A total of 32 cases with blue-white variant of basal cell carcinoma were observed over a period of 10 years. Of these cases, 97% presented dermatoscopic findings not included in the aforementioned criteria, such as whitish septa, structureless white areas, homogenous blue pigmentation and shiny white structures. LIMITATIONS: The small sample size and the retrospective nature of the design. CONCLUSION: We consider it important for dermatologists to know this rare variant of basal cell carcinoma and to familiarize themselves with their dermatoscopic findings, in order to prevent erroneous diagnoses or inadequate treatments.

Nevoid acanthosis nigricans: Report of four cases localized to the umbilicus.

Nevoid acanthosis nigricans is a rare, benign form of acanthosis nigricans. Of the 24 cases documented in the literature, only two are exclusively localized to the umbilicus. We present four cases of nevoid acanthosis nigricans localized to the umbilicus; in patients less than 25 years of age, with no known co-morbidities, three of whom were females. Two of the cases received, with good response, treatment based on topical calcipotriol, a medication not previously reported to be used for this indication. Contrary to other types of acanthosis nigricans, the nevoid acanthosis nigricans is not associated with any syndrome, endocrinopathy, obesity, medication, or neoplasia and it can be confused with other pathologies such as epidermal nevus or dermatosis neglecta.

A study of the association of acanthosis nigricans with subclinical atherosclerosis.

BACKGROUND: Hyperinsulinism is related to the presence of acanthosis nigricans and atherosclerosis; however, we were unable to find any study on the prevalence of atherosclerosis in acanthosis nigricans. AIMS: To evaluate the prevalence of carotid atherosclerosis and metabolic alterations in Mexican patients with acanthosis nigricans. METHODS: We carried out a cross-sectional study that included 45 patients with acanthosis nigricans, age- and gender-matched with 45 healthy participants. Volunteers with any comorbidity or taking weight reduction, glucose- and/or lipid-lowering medication or drugs capable of causing acanthosis nigricans were not included in the study. B-mode ultrasound tests were done to measure the carotid intima-media thickness. Body mass index, insulin, glucose and lipid blood serum levels were measured. Chi-square or Fisher's exact test and paired Student t-test were used for statistical analysis. RESULTS: Carotid intima-media thickness was greater in patients with acanthosis nigricans (mean 0.52 mm vs. 0.46 mm, P = 0.002). The prevalence of abnormal intima-media thickness was higher in patients with acanthosis nigricans versus healthy participants (62.2% vs. 35.5%, P = 0.02). The same occurred with hyperinsulinemia (73.3% vs. 13.3%, P< 0.001), insulin resistance (86.6% vs. 33.3%, P< 0.001), obesity (86.6% vs. 13.3%, P< 0.001) and dyslipidemia (95.5% vs. 77.7%, P = 0.01). LIMITATIONS: The sample size is small and serum markers of cardiovascular risk were not measured. CONCLUSION: Acanthosis nigricans is a skin marker for metabolic disturbances and is also associated with carotid atherosclerosis, a finding which is not well documented. We propose that individuals with acanthosis nigricans should be routinely evaluated for these cardiovascular risks.