Hodgkin's disease variant of Richter's syndrome. Report of a case with diagnosis by fine needle biopsy.

BACKGROUND: Chronic lymphocytic leukemia (CLL) with transformation into large cell lymphoma (Richter's syndrome) is a well-documented phenomenon. Only rarely does CLL terminate in Hodgkin's disease (HD) as Richter's syndrome. Reports of Hodgkin's variant of Richter's syndrome proven by histologic and immunohistologic evaluation have been published, but no cytologic reports of this entity exist. Distinguishing between large cell lymphoma and HD as variants of Richter's syndrome is essential because of recent reports of improved prognosis in HD. CASE: We report a case of a 65-year-old male previously diagnosed with CLL who subsequently developed fever, fatigue, an intraabdominal mass and enlarged periaortic lymph nodes. Fine needle biopsy (FNB) and immunophenotyping by flow cytometry of the mass revealed cytologic and immunophenotypical cells of CLL admixed with binucleate and multinucleate cells with prominant eosinophilic nucleoli consistent with Reed-Sternberg cells.
CONCLUSION: This is the first reported case of HD variant of Richter's syndrome diagnosed by FNB. As FNB becomes more common in the follow-up of lymphoreticular diseases, cytologists should be aware of this unusual HD variant of Richter's syndrome.