Tolerability of BRAF and MEK Inhibitors for Metastasized Melanoma after Intra-Class Switch: A Multicenter, Retrospective Study.

Targeted therapy with BRAF and MEK inhibitors (BRAFi, MEKi) is one of the mainstays of melanoma treatment. When dose-limiting toxicity (DLT) is observed, an option represents the intra-class switch to a different BRAFi+MEKi combination. Currently, there is scarce evidence for this procedure. This is a multicenter, retrospective analysis from six German skin cancer centers of patients who received two different combinations of BRAFi and MEKi. In total, 94 patients were included: 38 patients (40%) were re-exposed with a different combination because of previous unacceptable toxicity, 51 (54%) were re-exposed after progression, and 5 (5%) were included for other reasons. Of the 44 patients with a DLT during their first BRAFi+MEKi combination, only five (11%) experienced the same DLT during their second combination. A new DLT was experienced by 13 patients (30%). Six patients (14%) had to discontinue the second BRAFi treatment due to its toxicity. Compound-specific adverse events were avoided in the majority of patients by switching to a different combination. Efficacy data were similar to historical cohorts of BRAFi+MEKi rechallenge, with an overall response rate of 31% for patients who had previously progressed to treatment. We conclude that switching to a different BRAFi+MEKi combination if dose-limiting toxicity occurs is a feasible and rational approach in patients with metastatic melanoma.

Seborrheic Keratosis With Sebaceous Differentiation, a Series of 8 Cases and Critical Review of the Literature.

ABSTRACT: Seborrheic keratosis with sebaceous differentiation (SKSD) can sometimes raise uncertainty, confuse with other even malignant entities, and lead to overestimation of this harmless variant. Retrospective analysis of the cases diagnosed as SKSD and a search of the pertaining literature were conducted. Eight cases of SKSD were found. Histologically, these lesions show a flat to plate-like outgrowth of basaloid cells with solitary or clustered sebocytes at the bottom of the rete ridges and variable sebaceous ducts with luminal cuticula. The lesions differed in the outgrowth subpattern: flat/macular, acanthotic, or reticulated. No association was found with Muir-Torre syndrome, and no malignant transformation was seen in these lesions. Literature search revealed confusingly designated lesions that simply represented SKSD. SKSD can show several growth patterns as classic SK. This entity is either underreported or even underrecognized. This entity is benign; however, according to the literature, exclusion of an associating Muir-Torre syndrome should be warranted. The published literature about this lesion is confusing and inconsistent. We suggest the avoidance of confusing terminology and particularly the terminus epithelioma for such lesions.

Juvenile Blastic Plasmacytoid Dendritic Cell Neoplasm.

is missing (Short communication).

Guidelines for uveal melanoma: a critical appraisal of systematically identified guidelines using the AGREE II and AGREE-REX instrument.

PURPOSE: Clinical practice guidelines provide recommendations for the management of diseases. In orphan conditions such as uveal melanoma (UM), guideline developers are challenged to provide practical and useful guidance even in the absence of high-quality evidence. Here, we assessed the methodological quality and identified deficiencies of international guidelines on UM as a base for future guideline development. METHODS: A systematic search was carried out in guideline databases, Medline and Embase until 27th May 2019 for guidelines on UM published between 2004 and 2019. Five independent reviewers assessed the methodological quality of the identified guidelines using the instruments "Appraisal of Guidelines for Research and Evaluation II" (AGREE II) and AGREE-REX (Recommendation EXcellence). Descriptive analysis was performed and subgroup differences were explored with the Kruskal-Wallis (H) test. The relationship between the individual domains and items of the instruments were examined using Spearman's correlation. RESULTS: Five guidelines published from 2014 to 2018 by consortia of the United States of America, Canada and the United Kingdom (UK) were included. The highest scores were obtained by the UK guideline fulfilling 48-86% of criteria in AGREE II and 30-60% for AGREE-REX. All guidelines showed deficiencies in the domains "editorial independence", "applicability", and "recommendation". Subgroup differences were identified only for the domain "editorial independence". CONCLUSION: The UK guideline achieved the highest scores with both instruments and may serve as a basis for future guideline development in UM. The domains "editorial independence", "recommendation", and "applicability" were identified as methodological weaknesses and require particular attention and improvement in future guidelines.

Primary leiomyosarcoma of the skin: a comprehensive review on diagnosis and treatment.

Sarcomas are a heterogeneous group of mesenchymal tumors which can affect bone and soft tissue. Leiomyosarcoma (LMS) is a rare subtype localized to the skin or subcutaneous tissue. Due to the heterogeneity of sarcomas, reviews and guidelines with an in-depth focus specifically on primary LMS of the skin are sparse. This article is intended to provide an up to date and systematic overview on diagnosis, treatment, and surveillance of this rare entity to provide a framework for decision making and management for dermato-oncologists. We discuss novel treatment options for advanced disease such as targeted therapy with kinase inhibitors and immune checkpoint blockade which may improve the prognosis even in advanced stages of LMS.