Dermoscopy as a clinical tool for the diagnosis of demodicosis: a retrospective intrapatient case-control study.

Dermoscopy has been used for the non-invasive diagnosis of demodicosis. Several studies have evaluated the usefulness of this tool in the diagnosis, however, there are differences in the gold standard (SSSB or KOH test) and criteria of positivity used between studies. Added to this, is the lack of controls and objective quantification of the usefulness of dermoscopic signs in clinically observable and relevant ranges. To validate the usefulness of dermoscopy for the diagnosis of demodicosis by calculating the performance indicators for the different dermoscopic signs. Retrospective intrapatient case-control study, which included adults with suspicion of demodicosis. Dermoscopic photographs and scraping of healthy and lesional skin were obtained. Samples were analyzed microscopically by trained personnel. Photographs were evaluated by determining the presence of Demodex tails (DT), dilated follicular openings (DFO) and dilated blood vessels (DBV) in pre-defined ranges. 64 patients were included (total = 256 samples); the presence of demodex on skin scraping was seen in 69%. Under dermoscopy, the presence of DT in range 11-20/field had a positive likelihood ratio (LR) of 12.10 (95%CI 6.52-22.45) and negative LR 0.32 (95%CI 0.23-0.45). Combined and dichotomized performance for at least one positive sign under dermoscopy (DT > 10/field, DFO > 10/field or DBV > 50% of the field): positive LR 7.14 (95%CI 4.80-10.62) and negative LR 0.11 (95%CI 0.06-0.22). The presence of DT, DFO or DBV has a high correlation with a positive mite test, so the diagnosis of demodicosis could be made only through dermoscopy.

Predictive and Prognostic Factors in Melanoma Central Nervous System Metastases-A Cohort Study.

BACKGROUND: Melanoma is the cancer with the highest risk of dissemination to the central nervous system (CNS), one of the leading causes of mortality from this cancer. OBJECTIVE: To identify patients at higher risk of developing CNS metastases and to evaluate associated prognostic factors. METHODS: A cohort study (1998-2023) assessed patients who developed CNS melanoma metastases. Multivariate logistic regression was used to identify predictive factors at melanoma diagnosis for CNS metastasis. Cox regression analysis evaluated the CNS-independent metastasis-related variables impacting survival. RESULTS: Out of 4718 patients, 380 (8.05%) developed CNS metastases. Multivariate logistic regression showed that a higher Breslow index, mitotic rate ≥ 1 mm2, ulceration, and microscopic satellitosis were significant risk factors for CNS metastasis development. Higher patient age and the location of the primary tumor in the upper or lower extremities were protective factors. In survival analysis, post-CNS metastasis, symptomatic disease, prior non-CNS metastases, CNS debut with multiple metastases, elevated LDH levels, and leptomeningeal involvement correlated with poorer survival. CONCLUSION: Predictive factors in the primary tumor independently associated with brain metastases include microscopic satellitosis, ulceration, higher Breslow index, and trunk location. Prognostic factors for lower survival in CNS disease include symptomatic disease, multiple CNS metastases, and previous metastases from different sites.