Keratoacanthoma Centrifugum Marginatum with Spontaneous Regression and Its Possible Differential Diagnosis

Keratoacanthoma centrifugum marignatum (KCM) is a rare variant of keratoacanthoma, which is characterized by the dense infiltration of inflammatory cells throughout the dermis, especially around the keratinocytic islands. Therefore, it is sometimes difficult to differentiate between KCM and cutaneous T-cell lymphomas. In this report, we describe a case of KCM with spontaneous regression that showed dense infiltration of CD3+CD8+ T cells. Our present case suggested the importance of investigating tumor-infiltrating lymphocytes to avoid the misdiagnosis of KCM as cutaneous T-cell lymphoma

Association of Baseline Serum Levels of CXCL5 With the Efficacy of Nivolumab in Advanced Melanoma

Anti-programmed cell death protein 1 (PD1) antibodies are in wide use for the treatment of various cancers. PD1 antibody-based immunotherapy, co-administration of nivolumab and ipilimumab, is one of the optimal immunotherapies, especially in advanced melanoma with high tumor mutation burden. Since this combined therapy leads to a high frequency of serious immune-related adverse events (irAEs) in patients with advanced melanoma, biomarkers are needed to evaluate nivolumab efficacy to avoid serious irAEs caused by ipilimumab. This study analyzed baseline serum levels of CXCL5, CXCL10, and CCL22 in 46 cases of advanced cutaneous melanoma treated with nivolumab. Baseline serum levels of CXCL5 were significantly higher in responders than in non-responders. In contrast, there were no significant differences in baseline serum levels of CXCL10 and CCL22 between responders and non-responders. These results suggest that baseline serum levels of CXCL5 may be useful as a biomarker for identifying patients with advanced cutaneous melanoma most likely to benefit from anti-melanoma immunotherapy

Serum Level of Soluble CD163 May Be a Predictive Marker of the Effectiveness of Nivolumab in Patients With Advanced Cutaneous Melanoma

Antibodies against programmed cell death protein 1, such as nivolumab and pembrolizumab, are widely used for treating various cancers, including advanced melanoma. Nivolumab significantly prolongs survival in patients with metastatic melanoma, and sequential administration with lipilimumab may improve outcomes when switched at the appropriate time. Biomarkers are therefore needed to evaluate nivolumab efficacy soon after first administration. This study analyzed serum levels of soluble cluster of differentiation 163 (sCD163) in 59 cases of advanced cutaneous melanoma and 16 cases of advanced mucosal melanoma treated using nivolumab. Serum levels of sCD163 were significantly increased after 6 weeks in responders compared to non-responders after initial administration of nivolumab for cutaneous melanoma. In contrast, no significant difference between responders and non-responders was seen among patients with non-cutaneous melanoma. These results suggest that sCD163 may be useful as a biomarker for selecting patients with advanced cutaneous melanoma most likely to benefit from anti-melanoma immunotherapy

Kinetic Analysis in Healthy Humans of a Novel Positron Emission Tomography Radioligand to Image the Peripheral Benzodiazepine Receptor, a Potential Biomarker for Inflammation

The peripheral benzodiazepine receptor (PBR) is upregulated onactivated microglia and macrophages and thereby is a useful biomarkerof inflammation. We developed a novel PET radioligand, [11C]PBR28,that was able to image and quantify PBRs in healthy monkeys and in arat model of stroke. The objective of this study was to evaluate the abilityof [11C]PBR28 to quantify PBRs in brain of healthy human subjects.Twelve subjects had PET scans of 120 to 180 min duration as well asserial sampling of arterial plasma to measure the concentration ofunchanged parent radioligand. One- and two-tissue compartmentalanalyses were performed. To obtain stable estimates of distributionvolume, which is a summation of Bmax/KD and nondisplaceable activity,90 min of brain imaging was required. Distribution volumes in humanwere only ~5% of those in monkey. This comparatively low amount ofreceptor binding required a two-rather than a one-compartment model,suggesting that nonspecific binding was a sizeable percentage comparedto specific binding. The time-activity curves in two of the twelve subjectsappeared as if they had no PBR binding—i.e., rapid peak of uptake andfast washout from brain. The cause(s) of these unusual findings areunknown, but both subjects were also found to lack binding to PBRs inperipheral organs such as lung and kidney. In conclusion, with theexception of those subjects who appeared to have no PBR binding, [11C]PBR28 is a promising ligand to quantify PBRs and localize inflammation associated with increased densities of PBRs

Dermoscopy Findings of Hidroacanthoma Simplex

Hidroacanthoma simplex (HAS), also known as intraepidermal eccrine poroma, is a rare eccrine adnexal tumor that tends to be misdiagnosed as other types of benign skin tumor, including clonal seborrheic keratosis. Notably, HAS is sometimes misdiagnosed and treated by cryosurgery as seborrheic keratosis, which could trigger the later development of porocarcinoma. Therefore, accurate diagnosis of HAS is indispensable for dermatologists to avoid the development of malignant tumors by an unsuitable treatment. In this report, we present the characteristic dermoscopy findings of HAS. Indeed, the dermoscopy findings might be related to the melanin-rich necrotic cells in the epidermis, which are quite different from dermoscopy findings of clonal seborrheic keratosis. As a previous report suggested, it is difficult for a dermatologist to differentiate HAS from clonal seborrheic keratosis by the naked eye. Our findings might be supportive for the early diagnosis of HAS

Successful Treatment of Advanced Primary Cutaneous Peripheral T-Cell Lymphoma with Oral Bexarotene Monotherapy

Bexarotene is a third-generation retinoid X receptor-selective retinoid that is widely used for the early treatment of advanced-stage cutaneous T-cell lymphomas. In this report, we describe a case of successful treatment of advanced primary cutaneous peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) with oral bexarotene monotherapy. After the administration of oral bexarotene at a dose of 300 mg/m2/day, all skin lesions and lymph nodes regressed, and complete remission was achieved for 1 year. Our case suggested that bexarotene monotherapy could be one of the possible therapies for the treatment of primary cutaneous PTCL-NOS

Widely Spread Unilateral Inflammatory Linear Verrucous Epidermal Nevus (ILVEN)

Inflammatory linear verrucous epidermal nevus (ILVEN) is an epidermal nevus that clinically and histologically mimics linear psoriasis. The pathogenesis of psoriasis has been widely investigated, with recent studies focusing especially on targeting proinflammatory cytokines such as IL-17A, TNFα, IL-23, and IL-12, while little is known about ILVEN. Since the treatment for ILVEN varies widely from the administration of topical ointment for psoriasis to invasive methods such as carbon dioxide gas laser, the differential diagnosis between ILVEN and psoriasis is necessary. In this report, we describe a case of widely spread unilateral ILVEN that clinically and histologically mimicked psoriasis vulgaris and could be diagnosed by immunohistochemical staining focused on the IL-36γ/IL-17A axis