Indurated nodules and plaques showing a dense plasma cell infiltrate as a cutaneous manifestation of Castleman's disease

Localized Plaques on the Scalp as Initial Presentation of Multicentric Plasmacytic Castleman Disease

Castleman disease (CD) is a rare heterogeneous lymphoproliferative disorder and presents as unicentric Castleman disease (UCD) or multicentric Castleman disease (MCD). Cutaneous manifestations of MCD are rare and variable. Here, we reported an unusual case of MCD that initially presented with localized plaques on the scalp.

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.

Idiopathic multicentric Castleman disease preceded by cutaneous plasmacytosis successfully treated by tocilizumab

A woman aged 45 years with a 1.5-year history of violaceous plaques on the forehead and chest presented with fever, weight loss and aggravation of the plaques. Inflammatory markers and interleukin-6 level were elevated, and superficial lymphadenopathies and splenomegaly were identified by CT scan. Immunohistochemical findings of the lymph node and the skin showed polyclonal plasmacytosis and follicular hyperplasia, leading to the diagnosis of idiopathic multicentric Castleman disease (iMCD) after human herpesvirus-8 infection was excluded. The patient was successfully treated with anti-interleukin-6 receptor antibody, tocilizumab, following relapse after prednisolone therapy.

Our literature review found 11 case reports of pathologically confirmed iMCD preceded by cutaneous plasmacytosis. The median duration of asymptomatic phase with only skin lesions was 7.5 years, whereas the phase lasted only for 1.5 years in our case. iMCD can develop shortly after asymptomatic cutaneous plasmacytosis. Tocilizumab can be a treatment of choice for this type of iMCD.

Idiopathic multicentric Castleman disease with pulmonary and cutaneous lesions treated with tocilizumab: A case report

BACKGROUND

Human herpes virus-8 (HHV-8)-negative, idiopathic multicentric Castleman disease (iMCD) is a rare and life-threatening disorder driven by proinflammatory cytokines, which is still poorly understood. Pulmonary parenchyma lesion is a rare condition in iMCD, which mainly manifests as lymphocytic interstitial pneumonia and is an indicator of severe iMCD. Cutaneous lesion is also very rare and mainly occurs in Asians. There have been few reports of iMCD patients with both skin and lung parenchyma involvement.

CASE SUMMARY

We present a Chinese man who complained about a 3-year history of intermittent dry cough and a 2-year history of diffuse reddish-brown maculopapules. Laboratory examination revealed polyclonal hypergammaglobulinemia and hypercytokinemia including interleukin 6. Chest computed tomography revealed small patchy shadows with ground-glass nodules scattered in two lobes and mediastinal lymphadenopathy. The pathological result of the lymph node was consistent with the plasma cell type of Castleman disease. As serum human immunodeficiency virus test and HHV-8 staining of the lymph node were negative, the patient was finally diagnosed with HHV-8 negative iMCD. He was treated with tocilizumab at an intravenous (i.v.) dose of 8 mg/kg every 2 wk combined with methylprednisolone at an i.v. dose of 80 mg/d initially with gradual dose tapering. Partial remission was achieved 9 mo later.

CONCLUSION

iMCD with lung parenchyma and skin involvement is a rare condition that requires clinicians’ attention and awareness for early diagnosis.

Cutaneous multicentric Castleman's disease mimicking IgG4-related disease

Castleman's disease, an uncommon lymphoproliferative disorder, can be difficult to differentiate from immunoglobulin (Ig) G4-related disease. The latter is typically characterized by elevated serum IgG4 levels and abundant IgG4-positive cells. However, multicentric Castleman's disease can also have elevated serum IgG4 levels and even fulfill the histological diagnostic criteria for IgG4-related disease. We present a case of cutaneous multicentric Castleman's disease mimicking IgG4-related disease. A 55-year-old Japanese woman developed erythematous and brown plaques on her back. Skin biopsy revealed regressive follicles with interfollicular plasmacytosis, and many plasma cells were positive for IgG4 (mean 263.67±79.19, range 214-355 per high power field). The IgG4-/IgG-positive cell ratios were 35.6%, 36.2%, and 48.4%, respectively, with an average of 40.6%, thus fulfilling the histological diagnostic criteria for IgG4-related disease. Furthermore, serum IgG4 level was significantly elevated (1490 mg/dl; normal range: 4.8-105 mg/dl). However, laboratory findings of anemia, hypoalbuminemia, polyclonal gammaglobulinemia, high C-reactive protein level, and elevated serum interleukin-6 level were consistent with hyper-IL-6 syndrome. Hence, the diagnosis of cutaneous multicentric Castleman's disease was made. In conclusion, IgG4-related disease cannot be differentiated from hyper-IL-6 syndromes on histology alone. Instead, laboratory analyses are necessary to distinguish between the two diseases.

Castleman's Disease with Cutaneous Involvement Manifestating as Multiple Violaceous Plaques on Entire Body

Castleman's disease (CD) is an uncommon B-cell lymphoproliferative disorder characterized by lymph node hyperplasia with vascular proliferation. Cutaneous involvement in CD is rare. A 65-year-old man presented with a 7-year history of gradually developing multiple reddish to violaceous indurated plaques on the scalp, trunk, and legs. On physical examination, there were palpable enlarged cervical, axillary, and inguinal lymph nodes. Laboratory examination revealed anemia, thrombocytosis, hyperproteinemia, hypoalbuminemia, and polyclonal hypergammaglobulinemia. An inguinal lymph node biopsy and a skin biopsy were performed and the patient was diagnosed with the plasma cell type of CD. Chemotherapy was started and the lesions have responded to treatment.

Cutaneous and systemic plasmacytosis vs. cutaneous plasmacytic castleman disease: review and speculations about pathogenesis

Cutaneous and systemic plasmacytosis (C/SP), human herpes virus-8 (HHV8), negative multicentric plasmacytic Castleman disease (MPCD), and idiopathic plasmacytic lymphadenopathy are polyclonal plasma cell proliferations of unknown etiology that predominantly affect Asian individuals. Herein, we present our experience with a Vietnamese man with typical C/SP limited to the skin but, after 10 years, may have developed perirenal involvement, and with a white man with human immunodeficiency virus and HHV8 negative MPCD with involvement of skin, lymph nodes, and kidneys at presentation, and who later succumbed to gastric carcinoma. Based on a review of the literature, we suggest that C/SP, cutaneous MPCD, and idiopathic plasmacytic lymphadenopathy with skin involvement are part of a continuum rather than distinct entities and, as such, may be regarded as variants of HHV8-negative MPCD. Although the majority of patients with C/SP run a chronic benign course, special attention should be given to monitoring for pulmonary and renal involvement. We hypothesize that long-lived plasma cells originate and survive in the environment of the skin akin to other stromal "survival" niches due to the local production of interleukin 6 and that such patients might respond to agents that interfere with interleukin-6 activity.