The Gastrointestinal Microbiome and Immune Checkpoint Inhibitors: A Review of Human Interventional Studies Among Melanoma Patients.

Immune checkpoint inhibitors (ICI) are widely utilized for the treatment of malignant melanoma. Interestingly, gastrointestinal microbiome composition has emerged as a predictive biomarker of immunotherapy outcomes. This review seeks to assess the effect of microbiota-modulatory interventions on the clinical and immunological response of metastatic melanoma treated with ICIs. A systematic search was performed to retrieve studies and cases involving any microbiota-modulating intervention. Three studies assessed the effect of fecal microbiota transplantation (FMT) on ICI efficacy, and one case report assessed its effect on clearance of ICI-associated colitis. Overall, 37.5% of melanoma patients who had been previously refractory to ICI immunotherapy demonstrated complete or partial response following FMT and subsequent immunotherapy. 65% of immunotherapy-naïve melanoma patients demonstrated an objective response. No severe FMT-associated adverse events were reported, and FMT depicted efficacy in the remission of ICI-associated colitis. The results suggest that FMT may be a safe and moderately effective microbiota-modulating intervention to improve the efficacy of therapy in ICI-treated melanoma patients. Large, randomized, controlled trials are needed to determine optimal FMT donors and assess other microbiota-modulating interventions, such as pre- and probiotics, in melanoma patients.  J Drugs Dermatol. 2024;23(2):78-84.     doi:10.36849/JDD.7674.

Diagnosis of pili trianguli et canaliculi by frozen section: A rapid and inexpensive method of diagnosis.

We present frozen section as a novel method in the diagnosis of pili trianguli et canaliculi that may serve as a more time- and resource- efficient alternative to current gold- standard electron microscopy. In this case series, three children between ages one and four presented with blonde hair unable to be combed into place. Frozen section was performed and evaluated under light microscopy with easy visualization of the hair shaft abnormality, consistent with the diagnosis of pili trianguli et canaliculi.

Erythema Ab Igne: A Clinical Review.

Erythema ab igne (EAI) is a skin condition caused by chronic heat-induced damage. The rash usually progresses over weeks to months of repeated or prolonged exposure to subthreshold-intensity infrared radiation that is not hot enough to cause a burn. The diagnosis is clinical based on patient history and physical examination, but a biopsy can reveal dilated vasculature, interface dermatitis, and pigment incontinence. Erythema ab igne initially was described in association with patients cooking over wood-fire stoves but has been shown over the decades to have a variety of causes. Herein, we describe various etiologies of EAI, including new heat-producing technologies, cultural practices, psychiatric illnesses, and even iatrogenic causes. However, the cause most commonly is application of heat for treatment of chronic pain, which may be a diagnostic clue for an underlying chronic illness. Although there are no current US Food and Drug Administration-approved therapies for treatment of EAI hyperpigmentation, the prognosis is excellent because removal of the heat source often will result in spontaneous resolution over time. Finally, chronic EAI rarely has been reported to evolve into squamous cell carcinoma, poorly differentiated carcinoma, cutaneous marginal zone lymphoma, and even Merkel cell carcinoma.

Efficacy and safety of topical treatments for seborrheic keratoses: a systematic review.

Seborrheic keratoses (SKs) are benign epidermal neoplasms presenting as waxy, brown to black papules and plaques. Patients often seek removal for cosmetic reasons or irritation. The objective of this systematic review is to assess the efficacy and safety of topical treatments for SKs. Studies involving any topical medication indicated for SK removal were retrieved from Embase, Scopus, PubMed, and Cochrane. The final search was conducted on November 9, 2021, and 26 reports met inclusion criteria. A quality rating scheme was utilized to assess evidence quality. Heterogeneity of treatments and outcome measures precluded meta-analysis. Topical treatments that yielded a good-to-excellent response include hydrogen peroxide, Maxacalcitol 25 µg/g, BID Tazarotene 0.1% cream, 5% potassium dobesilate cream, 1% diclofenac sodium solution, urea-based solution, and 65% and 80% trichloroacetic acid. Local skin reactions were often mild and transient. Topical hydrogen peroxide showed the greatest evidence for clinical clearance of SKs, although there are no studies to our knowledge that directly compared hydrogen peroxide to current first-line treatments (e.g. cryotherapy or shave excision). The results of this review suggest viable and safe treatment of SK with topical therapies; however, there remains demand for topical treatments that reliably equate or exceed the efficacy of current first-line therapies.Key PointsQuestion: Are safe and efficacious topical treatments for seborrheic keratoses available?Findings: Topical treatments for seborrheic keratoses yield different responses and may be associated with local skin reactions. Topical hydrogen peroxide shows the greatest evidence for clinical clearance of seborrheic keratoses and may be a viable option for patients requesting noninvasive removal. No studies to our knowledge directly compare hydrogen peroxide to current first-line treatments.Meaning: There remains demand for topical treatments that reliably equate or exceed the efficacy of current first-line therapies.

Update in Diagnosis and Management of Primary Cutaneous B-Cell Lymphomas.

Primary cutaneous lymphomas are a rare group of diseases, with an estimated incidence of 0.5-1 case per 100,000 people per year. Primary cutaneous B-cell lymphomas (pCBCLs) represent 25-30% of all primary cutaneous lymphomas. There are three main subtypes of pCBCL: primary cutaneous marginal zone lymphoma, primary cutaneous follicle center lymphoma, and primary cutaneous diffuse large B-cell lymphoma, leg type. Cutaneous B-cell lymphomas have a broad spectrum of clinical presentations, which makes diagnostic and therapeutic strategies challenging. To date, treatment recommendations for cutaneous B-cell lymphomas have been largely based on small retrospective studies and institutional experience. Recently, the pharmacotherapeutic landscape has expanded to include drugs that may modify the underlying disease pathology of pCBCLs, representing new therapeutic modalities for this rare group of diseases. Novel therapies used for other systemic B-cell lymphomas show promise for the treatment of pCBCLs and are being increasingly considered. These new therapies are divided into five main groups: monoclonal antibodies, immune checkpoint inhibitors, small-molecule inhibitors, bispecific T-cell engaging, and chimeric antigen receptor T cell. In this review, we discuss the clinical, histopathological, molecular, and cytogenetic features of the most common pCBCL subtypes with a focus on current and innovative therapeutic developments in their management. These emerging treatment strategies for B-cell lymphomas and cutaneous B-cell lymphomas may represent novel first-line options for the management of these rare diseases.