Thyroid Rosai-Dorfman disease with infiltration of IgG4-bearing plasma cells associated with multiple small pulmonary cysts

Abstract

Background Rosai-Dorfman disease (RDD) is a rare histiocytosis which involves principally lymph nodes. Thyroid involvement in RDD is a very rare situation, and lung involvement is even rarer. Case presentation We report the case of a 46-year-old woman presenting a painless mass in the right side of the neck and subacute dyspnoea. Computerised tomography (CT) scans of the neck and thorax showed a large thyroid mass causing tracheal stenosis and multiple cystic lesions in both lungs. Subtotal thyroidectomy with a tracheal segment resection and histological analysis confirmed the diagnosis of nodal and extranodal (thyroid, tracheal and probably lung) Rosai-Dorfman disease (RDD) with the presence of increased numbers of IgG4-bearing plasma cells. Clinical, functional and radiological follow up 4 years after surgery without medical treatment did not show any disease progression. Conclusions This case report indicates a benign course of nodal RDD with thyroid and tracheal infiltration following surgical resection, association of typical histological signs of RDD (emperipolesis) with IgG4-related disease features, and that lung cysts might be a manifestation of RDD.

IgG4‐positive plasma cells in Hashimoto thyroiditis: IgG4‐related disease or inflammation‐related IgG4‐positivity?

“…Importantly, HPF adjustment is needed to be able to compare the results of various studies (34). In addition, the non‐specific presence of IgG4‐positive cells in various conditions such as inflammation and lymphoproliferative disorders was reported (10‐15, 34) and the presence of both IgG4‐positive cells and at least two histopathological features is required (32). IgG4‐RD histopathological features are viewed non‐specific when individually present, but they possess collectively a strong evidence (32, 35).…”

“…Nevertheless, the presence of IgG4‐positive plasma cells without accompanying histopathology can lead to overdiagnostics as IgG4‐positive cells were described in a wide range of inflammatory and lymphoproliferative disorders (10‐15). In addition, a raised serum IgG4 level is neither necessary nor adequate for the diagnosis (16, 17).…”

Cytologic and histological features of rare nonepithelial and nonlymphoid tumors of the thyroid

“…Rosai‐Dorfman disease (RDD), also known as sinus histiocytosis with massive lymphadenopathy, is a rare proliferation of distinctive histiocytes that primarily involves lymph nodes 109‐116 . Thyroid gland involvement is rare and usually occurs in the context of cervical lymph node or systemic involvement 114‐116 .…”

“…Extranodal involvement of RDD has been reported in 43% of cases, mostly in the skin, central nervous system, and salivary glands. Published data show that RDD occurs mostly in women with a mean age of 56 years 109‐116 . Thyroid involvement is usually discovered incidentally.…”

“…Autoimmune disorders (eg, autoimmune hemolytic anemia, pernicious anemia with gastritis) can be seen in 13% of RDD cases. Gianella et al 111 report that thyroid and tracheal infiltration by RDD can have increased numbers of immunoglobulin G4 (IgG4)‐bearing plasma cells. RDD and IgG4‐related disease share some similar features; differentiation between the two is based on the presence of the distinctive histiocytes and the degree of IgG4‐positive infiltrates and IgG4/IgG ratio 110 …”