Differential diagnostic problems in the radiologic evaluation of histiocytic lymphoma.

Medical records, pathologic records, an radiologic examinations of 112 patients with histiocytic lymphoma (HL) were reviewed. Peripheral lymph node enlargement was initially present in less than 50%, while HL presented as localized intraabdominal or intrathoracic lesions in 29% and 13%, respectively. Diagnostic problems encountered during the radiologic evaluation of patients with HL included the following: 1) Localized intraabdominal and intrathoracic lesions could mimic a variety of diseases, most often carcinoma. 2) Intercurrent (opportunistic) infections, which were commonly found in the lungs, and more rarely in the distal esophagus and bone, could easily be mistaken for HL manifestations. 3) Cytotoxic drugs and/or steroids produced pulmonary infiltrates, gastric ulcers, and collapsed vertebral bodies were often indistinguishable from an HL manifestation. 4) A second malignancy, found in 10% of patients either before or after HL was diagnosed, was difficult to differentiate from HL. 5) Aspiration biopsy of localized intraabdominal or intrathoracic HL under fluoroscopic control was unreliable in establishing the correct diagnosis.