Clinicolopathological, Cytogenetic, and Radiographical Analysis of Waldenstrom Macroglobulinemia in Japan: Unique Disease Manifestation

Abstract

Waldenstr?m macroglobulinemia (WM) is a rare lymphoid malignancy. Many studies, including clinicopathological, cytogenetic, gene expression profile, and therapy studies have been reported from the US and Europe, although only a few reports are available from East Asia, including Japan. To further clarify the clinicopathological, radiological, and cytogenetic features of WM in Japan, we performed a retrospective analysis of WM in our institute between March 2007 and January 2012. Clinical data, laboratory data, the results of flow cytometric analysis (FCM), and chromosomal abnormalities were analyzed, and a radiological review was performed. The treatment regimen, response, and survival were also estimated. Six patients were enrolled in this study. The median age was 71 years. All patients were symptomatic, 3 had hyperviscosity syndrome, 1 had bone lesions, and 1 had an extra-medullary mass. FCM data showed that all patients were positive for CD38, while 2 were positive for CD56. Four had chromosomal abnormalities including some abnormalities also reported in myeloma. On radiological review, four showed diffuse invasion of the retro-peritoneum. Five patients received treatment, 4 of which achieved a response. At a median follow-up of 527 days, 4 were alive and 2 died because of disease progression. The present study revealed that WM in Japan might be heterogeneous and have a unique disease manifestation. Invasion sites other than bone marrow were very common, and the results of clinical, FCM, and cytogenetic studies revealed that WM in Japanese cases might have manifestations of both myeloma and B-cell lymphoma.