A clinical study of 21 patients with hemophagocytic syndrome in 295 cases diagnosed with nasal type, extranodal nature killer/T cell lymphoma.

Nasal type, extranodal nature killer (NK)/T cell lymphoma-associated hemophagocytic syndrome (NK/T-LAHS) is a rare and fatal disorder with extremely poor prognosis. To investigate its clinical characteristics and risk factors, we retrospectively analyzed 295 patients with nasal type, extranodal nature killer/T cell lymphoma, of which 21 were diagnosed with hemophagocytic syndrome, with a cumulative incidence of 7.1%. The most frequently clinical characteristics were fever, lymphadenopathy, hepatosplenomegaly, pancytopenia, hyperferritinemia, liver dysfunction, hypertriglyceridemia, hypofibrinogenemia and evaluated lactate dehydrogenase (LDH) level. After a median follow-up of 27 months, the 2-year survival for the 295 patients was 74.6%. Significant difference for 2-year survival was found between patients with and without hemophagocytic syndrome (4.8% vs. 80.0%, P<0.001). After developing hemophagocytic syndrome, all patients survived no more than 3 months, with a median survival of 35 days. Risk factors for NK/T-LAHS were bone marrow (BM) involvement (P = 0.019; relative risk, 13.649; 95% confidence interval (CI): 1.538-121.103), hepatosplenomegaly (P = 0.003; relative risk, 9.616; 95%CI: 2.154-42.918), and elevated LDH level (>314U/L) (P = 0.038; relative risk, 6.293; 95%CI: 1.108-35.735). We conducted a risk model for all 295 patients based on the 3 adverse factors as follows: low risk (233 cases, 79.0%), no factor; intermediate risk (43 cases, 14.6%), one factor; high risk (19 cases, 6.4%), 2 or 3 factors. The probabilities for developing LAHS were 0.9% for low-, 14.0% for intermediate-, and 68.4% for high-risk group. Significant differences in the 3 risk groups were observed (P<0.001).