Comparison of Two PCR-Based Genetic Fingerprinting Methods for Assessment of Genetic Diversity in Saccharomyces Strains

Abstract

<b>1335</b> <h3><b>Learning Objectives</b></h3> 1. Present the imaging findings of FDG PET/CT, bone scan, Gallium scan, MRI and CT of hairy cell leukemia (HCL) with isolated bone lesions 2. Review clinical presentation and treatment of HCL, a rare B-cell lymphoproliferative disorder 3. Describe and compare the pathological findings of HCL and B-cell lymphoma <h3></h3> A 50 year old male presented with right hip pain. An MRI showed bilateral hip avascular necrosis. He subsequently had right hip decompression and bone graft, with the pathology showing increased lymphocytes of uncertain significance. Due to persistent right hip pain, a follow-up MRI was performed 2 years later which showed marrow replacing lesion in the right proximal femur that involved the epiphyses. A chest and abdominal CT identified anterior mediastinal, right paracardiac, retrocrural, and retroperitoneal lymphadenopathies. Core needle biopsies of the left paraspinal soft tissue mass were positive for lymphoid cell infiltration, with the morphological and immunophenotypic features in favor of nodal marginal zone lymphoma. However, the presence of positive cyclin D1 staining raised the possibility of a mantle cell lymphoma. Bone scan and Gallium scan were performed to rule out osteomyelitis. Susequently, bony lesions from the right femoral head and neck were biopsied and the final diagnosis is HCL. The original pathology from the paraspinal mass was reviewed and is consistent with HCL. The patient was later treated with a 5 day course of cladribine and on follow-up FDG PET/CT study was free of any disease in the right hip. HCL is a rare hematological malignancy representing 2% of all leukemias, with about 700 new cases diagnosed annually in the United States. We present a case of HCL in a male with persistent right hip pain, with unusual initial presentation of the bony lesions, followed 3 years later by soft tissue masses. In addition, the initial soft tissue biopsy was misdiagnosed as nodal marginal zone lymphoma. The distinction between hairy cell leukemia and marginal zone lymphoma is often difficult as they have many overlapping features.