Lymphnode localization of extramedullary myeloid cell tumor in myelodysplastic syndrome: report of one case diagnosed by fine-needle cytology

Clinicopathologic Features of Myelodysplastic Syndromes Involving Lymph Nodes

Lymph nodes (LNs) involved by a myelodysplastic syndrome (MDS) are rare and uncommonly biopsied. In this study, we report 6 MDS patients who underwent an LN biopsy that showed MDS, and we summarize the clinicopathologic features of this cohort. All patients presented with lymphadenopathy (generalized in 5), 5 patients had splenomegaly, and 3 patients had hepatomegaly. Histologically, the LN architecture was distorted without complete effacement. MDS cells, mostly of the myeloid lineage, produced interfollicular expansion. These myeloid cells exhibited a spectrum of maturation, and immature and atypical forms were common, including eosinophils. Scattered megakaryocytes and nucleated erythroid cells were often present. Concurrent bone marrow aspirate and biopsy specimens in these patients showed persistent/resistant MDS. Following the diagnosis of LN involvement, patients did not respond well to therapy and all died by the time of the last follow-up, with a median survival of 6.7 months (range, 4.5 to 21.6 mo). In summary, patients with MDS uncommonly develop clinically evident lymphadenopathy prompting biopsy as a result of infiltration by MDS. MDS in LNs can be subtle, showing incomplete and sometimes mild distortion of the architecture, and ancillary studies including immunohistochemical and flow cytometric immunophenotypic analysis are often needed to establish the diagnosis. These data also suggest that the emergence of lymphadenopathy attributable to MDS is associated with poor treatment response and prognosis in MDS patients and that aggressive therapy or alternative treatment regimens need to be explored in this context.