Clinical characteristics of Japanese pustular psoriasis: A multicenter observational study.

Generalized pustular psoriasis (GPP) is a rare and severe subtype of psoriasis. Because of its rarity, GPP studies with a large sample size have been scarce. We studied the characteristics of GPP and pustular psoriasis using data from the West Japan Psoriasis Registry that had been registered until the end of December 2020.

Establishment of the Western Japan Psoriasis Registry and first cross-sectional analysis of registered patients.

The efficacy and safety of new psoriatic treatments are confirmed in clinical trials, but such clinical trial data are limited by the number and heterogeneity of patients. Furthermore, the prevalence and characteristics of psoriasis differ among racial groups. Therefore, it is important to obtain real-world evidence in specific regions.

Mycobacterium tuberculosis infection in psoriatic patients treated with biologics: Real-world data from 18 Japanese facilities.

Although rare, tuberculosis has been reported with biologic treatment against psoriasis in Japan, a tuberculosis medium-burden country. Mycobacterial infection often develops after a long incubation period and might not have been adequately identified in clinical trials or post-marketing surveillance. To determine the real-world incidence of tuberculosis in psoriatic patients treated with biologics, we conducted a retrospective, multicenter, observational study in 18 facilities in Western Japan.

Cross-sectional multicenter observational study of psoriatic arthritis in Japanese patients: Relationship between skin and joint symptoms and results of treatment with tumor necrosis factor-α inhibitors.

Psoriatic arthritis (PsA) is an inflammatory arthritis with as yet unclear pathophysiology. This retrospective, multicenter, cross-sectional study was conducted in 19 facilities in western Japan and aimed to identify patients' characteristics and factors that affect the results of treatment with biologic agents. Of 2116 patients with psoriasis, 285 (13.

Hyperuricemia is an independent risk factor for psoriatic arthritis in psoriatic patients.

Psoriatic arthritis (PsA) is a spondyloarthritic condition mainly seen in patients with psoriasis. Psoriatic patients with plaques on the scalp, gluteal fold or nail lesions are known to develop PsA more frequently, but other markers for PsA have not yet been identified. To determine which psoriatic patients are at greatest risk of developing PsA, psoriasis vulgaris (PsV) patients who visited the Department of Dermatology, Fukuoka University Hospital in 2015 were enrolled.

Crater/ulcerated form of infundibular squamous cell carcinoma: A possible distinct entity as a malignant (or high-grade) counterpart to keratoacanthoma.

Follicular squamous cell carcinoma (SCC) with infundibular differentiation includes the common and crater forms of infundibular SCC. We previously considered the crater/ulcerated infundibular SCC to be a progressive condition of the common form and histopathologically studied an additional five cases of the crater/ulcerated infundibular SCC, the results of which suggested the following characteristic histopathological features and possible developmental process in this type of SCC: (i) a considerable number of continuous hyperplastic follicular infundibula, which may develop at the beginning of the disease; (ii) hyperplastic infundibula exhibiting an abrupt or gradual transition to the SCC component, which frequently change relative to the neoplastic infundibular canal; and (iii) the presence of multiple sites of branching of the neoplastic infundibular canals and/or complete involvement of large cysts in the neoplastic process over the center of the lesion, resulting in ulceration. Based on these histopathological findings, we considered that crater/ulcerated infundibular SCC involve a considerable number of continuous follicular infundibula from the start, although some cases may develop from the common form.

Sebaceous carcinoma in association with actinic keratosis: A report of two cases with an immunohistochemical study.

We report two cases of sebaceous carcinoma associated with actinic keratosis (AK) with an immunohistochemical study, which suggests the possibility that sebaceous carcinoma really does develop within AK. Case 1 had sebaceous carcinoma arising within the atrophic type AK and case 2 had sebaceous carcinoma associated with bowenoid AK in the periphery and some parts of the overlying epidermis of the lesion.

Triphasic differentiations of Merkel cell carcinoma in primary and metastatic lesions.

We present a rare case of Merkel cell carcinoma (MCC) with heterologous differentiation. The patient was an 86-year-old female patient with MCC who presented with a forearm skin tumor and left axillary lymph node swelling. Histopathologically, the malignant components of the primary and metastatic lesions showed the intermingled features of triphasic phenotype differentiation, which had distinct cell populations; MCC, sweat gland carcinoma (SGC) and malignant poorly differentiated spindle cells with myogenic differentiation were immunohistochemically showed.

Rippled-pattern basal cell carcinoma.

Basal cell carcinoma (BCC) is the most common malignant cutaneous neoplasm, however, there have been few studies on BCC with a "rippled pattern" so far. We reviewed the 650 BCC specimens from the archives of our institution, and only one example of BCC with a rippled pattern was found. We herein report the histopathological characteristics of this case.