Pancytopenia in a 70-year-old african-american male: an unusual presentation of a rare disease

Hairy cell leukemia presenting with a lytic bone lesion

Hairy cell leukemia (HCL) is an indolent neoplasm of small mature B lymphoid cells with characteristic morphologic features usually involving the peripheral blood, bone marrow, and spleen. It constitutes approximately 2% of adult leukemias and has a male predominance. Patients usually present with weakness, splenomegaly, and pancytopenia. The overall prognosis is favorable with appropriate treatment including purine analogs, interferon-alpha, and radiation. We report a patient with a history of breast cancer who presented with a left femoral lytic bone lesion that was subsequently diagnosed as HCL by morphology, immunohistochemistry, flow cytometry, and molecular genetic techniques. It was important to biopsy the lesion to establish the correct diagnosis, as HCL is a highly treatment-responsive malignancy.

Unusual presentation of hairy cell leukemia: a case series of four clinically unsuspected cases

Hairy cell leukemia (HCL) is characterized by pancytopenia and usually associated with massive splenomegaly, however the same may not be true in the clinical settings. Here we report four cases of HCL and all of them were without the classical clinical feature of splenomegaly. This is an observational study conducted between January 2013 to March 2014 where we could diagnose ten cases of HCL in Department of Hematology, All India Institute of Medical Sciences, New Delhi. Of these, four cases attracted attention because of absence of classical clinical features of HCL. Of the four cases, three presented with weakness/fatigability while fourth patient presented with recurrent respiratory tract infection. Surprising finding in these cases was absence of splenomegaly, both clinically and on imaging which demerit the suspicion of HCL clinically. All four had bi/pancytopenia and bone marrow examination coupled with immunophenotypic analysis confirmed the diagnosis of HCL. Three patients received chemotherapy with cladribine and achieved complete hematological remission. One patient did not receive chemotherapy due to poor general condition and was subsequently lost to follow up. To conclude, HCL can and do present without splenomegaly and this should not restrain one from suspecting HCL based on histomorphology which needs to be further confirmed by ancillary techniques. This finding in our series could be because these cases were picked early in their natural course of the disease. A high index of suspicion is essential for diagnosing and appropriately managing such cases.