Successful Surgical Treatment for Pulmonary Crystal-Storing Histiocytosis Following the Onset of Gastric Non-Hodgkin Lymphoma

Crystal-storing histiocytosis is a rare clinical entity characterized by an increase in the number of abnormal histiocytes accompanied by accumulation of crystallized immunoglobulins. We describe the case of an 80-year-old man who presented with crystal-storing histiocytosis of the lung 13 years after receiving a diagnosis of gastric non-Hodgkin lymphoma (NHL ; clinical stage, Lugano IA). After wedge resection of the left upper lobe, the histological findings showed crystal-storing histiocytosis with CD68 + , some small to medium lymphoid cells with CD79a + with k + (weekly) and l - , and some plasma cells with CD138 + , and rearrangement of the immunoglobulin heavy chain. Based on the nonrecurrent gastric NHL, small B-cell population, and failure to detect the same clone by polymerase chain reaction analysis, our case was classified as pulmonary localized crystal-storing histiocytosis without underlying lymphoproliferative or plasma cell disorder. The findings of minor Bcell populations harboring a heavy chain rearrangement with slight light-chain restriction (k > l) may be related to the pathogenesis of crystallogenesis and crystal-storing histiocytosis. Moreover, surgical treatment may be an effective therapeutic option for solitary crystal-storing histiocytosis. 〔J Clin Exp Hematop 53(3) : 241-245, 2013〕