INCIDENCE AND SIGNIFICANCE OF ABDOMINAL LYMPHADENOPATHY IN HAIRY-CELLLEUKEMIA

We have investigated the incidence and significance of abdominal lymph adenopathy in hairy cell leukemia (HCL) by routinely CT scanning 88 pa tients. These included 70 men and Is women with a median age of 51 yea rs (range 25-83). Abdominal CT scans were performed at diagnosis in 29 patients and in 59 during the course of the disease. Abdominal lympha denopathy was documented in 25 patients (28%) overall; the incidence o f abdominal lymphadenopathy was higher in relapse (56%) than at diagno sis (17%). All patients with lymphadenopathy had bone marrow disease. There is no association with age or sex but lymphadenopathy tends to b e more common in patients with longstanding disease (median duration o f disease 6 years v one year in those without nodes) and in patients w ith bulky disease, particularly in the relapse group (splenomegaly/spl enectomy in 95% vs 40%). The presence of abdominal nodes is also assoc iated with relative resistance to treatment, with more treatment failu res and fewer complete responses seen in this group. Most patients wit h lymphadenopathy had large, immature-looking hairy cells present in b oth the bone marrow and lymph nodes, when these were examined. Abdomin al lymphadenopathy in HCL is more common than previously recognised, p articularly in relapsed patients, and is always associated with active disease. The presence of large hairy cells and the relative resistanc e to treatment suggest that this phenomenon represents a form of trans formation of the disease. Longer follow up is required to confirm this .