Kimura's disease: A clinicopathological study of 23 cases

Abstract

Introduction: Kimura's disease (KD) is an uncommon lymphoproliferative fibroinflammatory disorder. Patients present with head and neck subcutaneous nodules with or without lymphadenopathy. Peripheral blood eosinophilia and elevated serum immunoglobulin E (IgE) levels are typical. This study was designed to delineate the clinicopathological features, pattern of care, and disease course of 23 Taiwanese patients with KD.

Methods: We retrospectively analyzed the clinical data of 23 consecutive cases (16 male and 7 female; age at diagnosis: 12-77 years) of KD diagnosed at our institution from 2015 to 2020.

Results: The median time from presentation to diagnosis was 1 month. Twenty-one patients presented with unilateral or bilateral head and neck masses. The remaining two presented with right flank and right arm lesions, respectively. Peripheral blood eosinophilia was observed in nine, and elevated IgE levels were observed in four. All were diagnosed using either excisional or core-needle biopsy. Seven patients underwent fine needle aspiration without a diagnostic yield. Salivary gland and lymph node involvement was observed in three and seven patients, respectively. Most lesions showed tissue eosinophilia (100%) and florid follicular hyperplasia (78.26%). Three cases had histological KD-IgG4-RD overlap and three had comorbid IgG4-RD were recognized. Thirteen patients underwent surgical resection, one received adjuvant therapy, and two received prednisolone monotherapy.

Conclusion: KD should be considered in patients with subcutaneous masses, eosinophilia, and elevated IgE levels. Biopsy remains the gold standard of diagnosis. Increased recruitment of IgG4⁺ plasma cells is a common feature. Consideration of IgG4-RD in all KD patients may be prudent.

Keywords: IgG4-related disease; Kimura’s disease; Taiwan; eosinophilia; pathology.

FIGURE 1

Distribution of Kimura’s disease lesions in various parts of the body of 23 patients.

FIGURE 2

The percentage distribution of different lymphatic systems in seven patients with Kimura’s disease and lymphadenopathy.

FIGURE 3

Histopathological features of the 23 cases.

FIGURE 4

The development of Kimura’s disease is preceded by a series of chronic Th2-predominant inflammation. An inciting event (e.g., tissue injury and viral infection) leads to tissue exposure to self-antigens or entry of allergens. Antigens/allergens are taken up by dendritic cells (DCs) and presented to naive CD4 + T cells in germinal centers. Upon interaction with DCs, naive CD4 + T cells differentiate into CD4 + GATA3 + follicular T (Tfh) cells and helper T (Th2) cells. Tfh cells facilitate B cell class switching into IgE- and IgG4-secreting plasma cells. Antigen presentation via IgE activates mast cells and recruits them to KD lesion sites. Mast cell degranulation contributes to clinical symptoms of pruritus and atopy. Cytokines secreted by Th2 cells, including IL-4, IL-5, IL-13, eotaxin, and RANTES (regulated upon activation, normal T cell expressed and presumably secreted; CCL5), sustain a type 2 inflammatory milieu and induce activation and proliferation of eosinophils. Tissue infiltration of eosinophils and generalized eosinophilia ensue. Chronic antigen stimulation results in reactive lymphoproliferation with hyperplasia of germinal centers.