Crystal storing histiocytosis associated with marginal zone B-cell lymphoma: A rare initial clinical presentation diagnosed by fine-needle aspiration

Crystal-Storing Histiocytosis in a Patient with Nodal Marginal Zone Lymphoma

“…Accumulation of crystallized immunoglobin molecules within the cytoplasm of histiocytes may be seen in B-cell lymphomas with plasmocytic differentiation and plasma cell neoplasms [1][2][3]. While the molecular basis has not been established, it is conceivable that stored immunoglobulins have acquired abnormal crystallization characteristics and/or have undergone intra-lysosomal degradation [4][5][6].…”

“…Crystal-storing histiocytosis (CSH) is a rare disorder in which crystallized material accumulates within the cytoplasm of histiocytes. Many authors have proposed that the crystallized material represents an intralysosomal accumulation of immunoglobulins [1,2], as most cases of CSH are associated with B-cell lymphomas with plasmacytic differentiation or plasma cell neoplasms [3][4][5]. In some cases, a dominant histiocytic component can obscure the underlying neoplasm, which can possibly lead to an error in diagnosis.…”