‘Mantle-Zone Lymphoma’ (MZL): Report of a Case Associated with Polyclonal Hypergammaglobulinemia and Review of the Literature Concerning the Identity of MZL

‘Mantle-zone lymphoma’ (MZL) with polyclonal hypergammaglobulinemia (PHG) in a 79-yr-old man is reported. In the cervical lymph node, vaguely nodular proliferation of monoclonal B cells as wide mantles was noted, and surface phenotypes of these cells were similar to those of MZL cells. Since several cases of MZL with PHG have been reported, the diagnosis of such cases require careful hematopathologic examinations. Whether MZL is a distinct clinicopathologic entity or not, appears to be a matter of debate. This confusion may be derived from the fact that the term MZL was originally employed without apparent definition whether it was based on morphology or surface phenotype (or histogenesis). It is stressed that examination of further MZL cases should be performed on the understanding of this controversial issue.