Hairy cell leukemia without splenomegaly nor myelofibrosis in a patient with gastric adenocarcinoma: early phase of the disease or a variant?

The first case of patient affected both by gastric carcinoma and hairy cell leukemia (HCL) is reported. From a clinical standpoint, this 54-year old man presented with striking leukopenia without splenomegaly. From a morphological point of view, the infiltration by leukemic cells occurred in the hypoplasic areas of the bone marrow biopsy (BMB) without increase in reticulin fibers. From these observations the authors deduce that: 1) BMB in many cases is the only morphologic tool for diagnosis and prognosis of HCL; 2) probably the "hypoplasic" variant of HCL will become more frequent, because of the increasing indication to BMB in course of pancytopenia, even in absence of splenomegaly; 3) our case is probably related more to an early phase of the disease than to a distinct variant. In addition, we propose that the co-existence of an aggressive solid tumor and HCL could be related to the immunosuppressive action by hairy cells.