Cutaneous plasmacytosis: a clinicopathologic study of 12 cases in Taiwan revealing heterogeneous underlying causes

Primary cutaneous plasmacytosis successfully treated with topical corticosteroids and psoralen plus ultraviolet A: A case report

We present a case of primary cutaneous plasmacytosis without systemic involvement. The patient received topical corticosteroids and psoralen plus ultraviolet A therapy, showing significant improvement. Continuous monitoring is underway despite the rarity of systemic manifestations.

Cutaneous plasmacytosis Characterized by Head Plaques: An Unusual Case Report of a 57-Year-Old Male

Cutaneous plasmacytosis (CP) is a rare disorder of uncertain etiology. We report an unusual and rare case of CP in a 57‑year‑old male who presented with popular nodules all over the body, accompanied by head plaques. Pathological biopsy of the skin revealed large infiltration of mature plasma cells within the dermis. Elevated serum IgG4 concentrations were found. Immunohistochemical analysis confirmed the polyclonal nature of the plasma cells. The diagnosis of CP was established. Steroid therapy was administered at a dose of 20 mg/day. After 1 month of treatment, the patient's eruption showed regression. These findings remind dermatologists to include CP in their clinical differential diagnosis of patients with head plaques. Meanwhile, clinicians should carefully that individuals diagnosed with CP at risk for malignant transformation.

Cutaneous Reactive B-cell Lymphoid Proliferations

Cutaneous lymphoid hyperplasia (CLH), also known as cutaneous pseudolymphoma, is a spectrum of benign conditions characterized by reactive B- and T-cell cutaneous lymphocytic infiltrates. B-cell lymphoid proliferations are a heterogenous group of non-neoplastic cutaneous diseases that must be histopathologically distinguished from cutaneous B-cell lymphomas. These proliferations can be observed as reactive phenomena to infections, medications, allergens, neoplasms, and more. Further, there are many inflammatory conditions that present with reactive B-cell infiltrates, including actinic prurigo, Zoon balanitis, Rosai-Dorfman, and cutaneous plasmacytosis. This review summarizes multiple cutaneous B-cell lymphoid proliferations within the major categories of reactive and disease-associated CLH. Further we discuss major discriminating features of atypical CLH and malignancy. Understanding the specific patterns of B-cell CLH is essential for the proper diagnosis and treatment of patients presenting with such lesions.

Non Epitheliotropic B-Cell Lymphoma with Plasmablastic Differentiation vs. Cutaneous Plasmacytosis in a 12-Years-Old Beagle: Case Presentation and Clinical Review

Cutaneous lymphoid neoplasms and cutaneous plasmacytosis are rare in the dog; in human and in veterinary medicine, these have many clinical, cytological, histological, and phenotypic similarities, and a diagnosis of certainty is not easy. The aim of this study is to describe a case of cutaneous non epitheliotropic B-cell lymphoma (CNEBL) with plasmablastic differentiation vs. multiple cutaneous plasmacytosis (CP) in a dog, since the scarce bibliographic data on these topics. A 12-year-old male Beagle dog was presented for multiple, nodular, cutaneous, and subcutaneous, indolent masses disseminated on the whole body. Cytological, histological, flow cytometric, and immunohistochemical examinations, as well as complete radiographic evaluation, echocardiography, and abdominal ultrasound were performed. Cytology, histopathology, flow cytometric, and immunohistochemical examination, performed on the skin lesions, revealed a B-cell phenotype with plasmablastic differentiation. Nevertheless, a final diagnosis could not be achieved and it was categorized as a case of borderline CNEBL with plasmablastic differentiation versus CP. The dog was treated with a COP chemotherapeutic protocol. Total remission was obtained and relapse occurred 120 days later. To our knowledge, specific markers are actually unavailable to certainly differentiate CNEBL and CP in the dog and future studies are needed to improve knowledge on these pathologies in veterinary medicine, since prognosis and therapy are different.

Skin diseases in Asian individuals that you do not want to miss: A selection of unique or relatively more common conditions in Asian populations

The Asian population currently constitutes a simple majority of the global population, comprising nearly 60%. The percentage of the US population that identifies as Asian is expected to grow to 41 million by the year 2050, making up an eventual 9% of the US population. As the world and US populations of Asian individuals increase, the demand for dermatologic care from this population will increase, requiring dermatologists to become more familiar with the diagnosis and treatment of Asian-specific skin characteristics and diseases. In this contribution, we review skin conditions specific to or relatively more common in Asian patients to help recognition and management of diseases in an increasing Asian patient population. We discuss prurigo pigmentosa, primary cutaneous plasmacytosis, lipodystrophia centrifugalis abdominalis infantilis, Epstein-Barr viru-positive T- and natural killer-cell lymphoproliferative disorders, acquired bilateral nevus of Ota-like macules, and Behҫet disease.

Kappa and lambda immunohistochemistry and in situ hybridization in the evaluation of atypical cutaneous lymphoid infiltrates

BACKGROUND

Atypical cutaneous lymphoid infiltrates are challenging lesions in dermatopathology. We present a summary of the literature regarding kappa and lambda immunohistochemistry (IHC) and in situ hybridization (ISH) in the evaluation of atypical cutaneous or mucosal lymphoid infiltrates.

METHODS

Relevant articles from 1967 to 2018 in the English language were identified and summarized. In the absence of larger studies, case series of n ≥ 3 were included.

RESULTS

Sixty-three articles assessing kappa and lambda IHC and/or ISH were identified. Most focused on marginal zone lymphomas. Other lymphomas included follicle center lymphoma, diffuse large B-cell lymphoma, chronic lymphocytic leukemia/small lymphocytic lymphoma, mantle cell lymphoma, lymphoplasmacytic lymphoma, plasmablastic lymphoma, multiple myeloma, monoclonal gammopathy of undetermined significance, and polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes (POEMS). Non-neoplastic lesions included reactive lymphoid hyperplasia, cutaneous plasmacytosis, connective tissue disease, IgG4-related disease, acrodermatitis chronic atrophicans, Zoon balanitis, dermatitides, and infiltrates around epithelial dysplasias/neoplasias.

CONCLUSION

Kappa and lambda IHC and ISH are useful tools in the evaluation of cutaneous B-cell lymphomas and plasma cell neoplasms. The literature supports that the detection of light-chain restriction by IHC and ISH is one of the most useful findings in the differential diagnosis of reactive lymphoid hyperplasia vs B-cell lymphoma with plasmacytic differentiation.

[Cutaneous plasmacytosis with Darier's sign in a woman of European origin]

INTRODUCTION

Cutaneous plasmacytosis is a rare skin condition first described in 1976 and it is seen mainly in patients of Asian descent. Patients usually present with multiple reddish-brown macules and nodules chiefly on the trunk and face, with clusters of well-differentiated plasma cells in the dermis. The aetiopathogenesis and nosological features of this entity remain obscure. We report herein a case of cutaneous plasmacytosis in a European middle-aged woman with presence of Darier's sign.

PATIENTS AND METHODS

A 56-year-old woman of European descent presented with asymptomatic hyperpigmented patches affecting the dorsal aspect of her trunk for at least two years. Darier's sign was present in some episodes. Cutaneous biopsy showed a moderately dense interstitial and perivascular infiltrate containing numerous well-differentiated mature plasma cells affecting the entire dermal surface. Kappa and lambda immunochemistry demonstrated polyclonal plasma cell infiltrates with absence of light-chain restriction. Immunohistochemical examination was negative for HHV-8 and Treponema pallidum spirochetes. Laboratory findings revealed hypergammaglobulinaemia with no monoclonal bands being detected on immunofixation. A diagnosis of cutaneous plasmacytosis was made. In the absence of systemic involvement initial management consisted of clinical surveillance.

DISCUSSION

The characteristic clinico-pathological features of CP allowed diagnosis of this skin condition in our patient, although it is very rarely reported in patients of European descent. The main differential diagnoses were ruled out, namely plasmacytic infiltrates related to infections and marginal B-cell lymphoma.

Cutaneous plasmacytosis with mast cell infiltration

Cutaneous plasmacytosis is a rare disorder of uncertain etiology, described mainly in patients of Japanese descent. Clinically, it is characterized by multiple pigmented papules and plaques distributed primarily on the trunk. Histopathologically, it is marked by a dense dermal plasma cell infiltrate. Here, we describe a case of cutaneous plasmacytosis in a 55-year-old Indian male who presented with hyperpigmented plaques on the body. Histopathological examination revealed dense superficial and deep perivascular and periappendageal infiltrate composed mainly of plasma cells, lymphoid follicles with reactive germinal centres, perineural distribution of plasma cells, mast cell infiltration and increased dermal small blood vessels. Immunohistochemical analysis confirmed the polyclonal nature of the plasma cells. Laboratory investigations were within normal limits, except for the presence of polyclonal hypergammaglobulinemia without any M band. There was no evidence of autoimmune disease or any infection. There was no systemic involvement in this patient. The patient was diagnosed as cutaneous plasmacytosis and advised long-term follow-up. Peculiar histopathological finding in this case of cutaneous plasmacytosis was the presence of abundant mast cells in the dermis.

A Rare Case of Cutaneous Plasmacytosis in a Korean Male

Cutaneous and systemic plasmacytosis are reactive disease processes that occur in middle-aged Japanese and Chinese men. Systemic plasmacytosis, defined by plasmacytic infiltration of two organ systems, might rarely progress to lymphoma. Cutaneous plasmacytosis, however, is chronic and benign and is characterized by the development of multiple plasma cell-rich infiltrates in the skin. We present a case of cutaneous plasmacytosis in a 46-year-old Korean male. The patient demonstrated classic features of the disease entity, including disseminated red-brown plaques, differentiated plasmacytoid infiltrates on biopsy, hypergammaglobulinemia, and the absence of systemic disease.