Dermatopathologic features of cutaneous squamous cell carcinoma and actinic keratosis: Consensus criteria and proposed reporting guidelines.

Background: There is considerable variation in the literature regarding the dermatopathologic diagnostic features of and reporting guidelines for actinic keratosis (AK) and cutaneous squamous cell carcinoma (cSCC).

Objective: To develop consensus recommendations regarding diagnostic criteria, nomenclature, and reporting of AK and cSCC.

Methods: Literature review and cross-sectional multiround Delphi process including an international group of expert dermatopathologists followed by a consensus meeting.

Milestones 2.0: An advancement in competency-based assessment for dermatology.

In 2013, Next Accreditation System and Milestones became the competency-based assessment framework required for all specialties accredited by the Accreditation Council for Graduate Medical Education. Dermatology residency programs implemented Milestones 1.0 in the 2013-2014 academic year.

Pityriasis rosea-like rash after messenger RNA COVID-19 vaccination: A case report and review of the literature.

A spectrum of cutaneous reactions to SARs-CoV-2 (COVID-19) vaccines have been reported in the literature. We present a case of a pityriasis rosea-like rash occurring after Pfizer COVID-19 vaccination and review cases of pityriasis rosea (PR)/PR-like eruption (PR-LE) after mRNA COVID-19 vaccine published in the medical literature. Of the 30 cases found, none experienced severe adverse effects and the rash resolved in an average of 5.

Cutaneous adverse events in 155 patients with metastatic melanoma consecutively treated with anti-CTLA4 and anti-PD1 combination immunotherapy: Incidence, management, and clinical benefit.

Background: In response to the increased use of combination checkpoint inhibitors (CPIs) and the resulting increased cutaneous adverse events (CAEs), this study reviewed patients with melanoma treated with combination CPIs to characterize CAE features and their clinical impact, correlation to adverse events in other organs, and correlation to tumor response.

Methods: Patients from the authors' institutional database who received at least 1 dose of ipilimumab in combination with either nivolumab or pembrolizumab between January 1, 2012, and December 31, 2017, for stage IV or unresectable stage III melanoma were identified. The time to next treatment (TTNT) was calculated from the start of CPI therapy to the start of the next treatment or death, and the development of CAEs was tested in a time-dependent Cox regression to identify associations with TTNT.

Diverse types of dermatologic toxicities from immune checkpoint blockade therapy.

Immunomodulatory drugs that leverages host immune mechanisms to destroy tumor cells have been met with great promise in the treatment of cancer. Immunotherapy, targeting cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and the programmed cell death 1 (PD-1) receptor and its ligand (PD-L1) have shown tremendous improvements in the survival of patients with advanced solid tumors. However, the development of dermatologic toxicity (DT) is a consequence to immunotherapy.

Concomitant Cutaneous Langerhans Cell Hystiocytosis and Leukemia Cutis.

Leukemia cutis develops in <4% of all acute leukemias. Concurrent acute myeloid leukemia (AML) and Langerhans cell histiocytosis (LCH) is rare, with most cases involving lymph nodes or spleen, and no cutaneous involvement. We report the case of a 59-year-old man who presented with fever, malaise, and fatigue.

Cross-species identification of genomic drivers of squamous cell carcinoma development across preneoplastic intermediates.

Cutaneous squamous cell carcinoma (cuSCC) comprises 15-20% of all skin cancers, accounting for over 700,000 cases in USA annually. Most cuSCC arise in association with a distinct precancerous lesion, the actinic keratosis (AK). To identify potential targets for molecularly targeted chemoprevention, here we perform integrated cross-species genomic analysis of cuSCC development through the preneoplastic AK stage using matched human samples and a solar ultraviolet radiation-driven Hairless mouse model.

Autoimmune dermatologic toxicities from immune checkpoint blockade with anti-PD-1 antibody therapy: a report on bullous skin eruptions.

Monoclonal antibodies against the immune checkpoint programmed cell death receptor 1 (PD-1) improve the hosts' antitumor immune response and have showed tremendous promise in the treatment of advanced solid tumors and hematologic malignancies. Reports of serious autoimmune dermatologic toxicities from immune checkpoint blockade therapy, however, are emerging. We report our experience with five patients who presented with pruritic vesicles and blisters on the skin while treated with anti-PD-1 antibody immunotherapy with either nivolumab or pembrolizumab.

Multifocal extramammary Paget's disease-associated adenocarcinoma: a rare condition of flexoral skin of multiple sites.

Extramammary Paget disease (EMPD) is a rare malignant neoplasm of apocrine sweat glands that is morphologically and histologically identical to Paget disease of the breast. The primary lesion is usually a solitary, well-demarcated, erythematous, scaly plaque that may contain crust, erosions, or ulcerations. The vulva is the most common site, but any area containing apocrine sweat glands may be involved.

A Comparative Study Between Smartphone-Based Microscopy and Conventional Light Microscopy in 1021 Dermatopathology Specimens.

Context: The incorporation of high-resolution cameras into smartphones has allowed for a variety of medical applications including the use of lens attachments that provide telescopic, macroscopic, and dermatoscopic data, but the feasibility and performance characteristics of such a platform for use in dermatopathology have not been described.

Objective: To determine the diagnostic performance of a smartphone microscope compared to traditional light microscopy in dermatopathology specimens.

Design: A simple smartphone microscope constructed with a 3-mm ball lens was used to prospectively evaluate 1021 consecutive dermatopathology cases in a blinded fashion.

Grape Cells (Multinucleated Keratinocytes) in Noninfectious Dermatoses: Case Series and Review of the Literature.

Multinucleated keratinocytes (also known as multinucleated epidermal giant cells) are a frequently overlooked histological finding in noninfectious inflammatory dermatoses. They are sometimes found in conditions characterized by chronic rubbing and pruritus, such as lichen simplex chronicus or prurigo nodularis, and may be a helpful clue in making the clinical diagnosis. This finding must be differentiated from other conditions characterized by multinucleated keratinocytes on histopathology, specifically herpes simplex, varicella zoster, or measles viral infections.

Morphea-like complications to illicit gluteal silicone injections.

We present a case of a 39-year-old Hispanic woman who was referred to our clinic for treatment of several indurated plaques on her buttocks that developed one year prior to presentation, after she received injections of an unknown substance for augmentation. Biopsy of one nodule revealed silicone in the dermis.