Overall survival according to serum lactate dehydrogenase (LDH) level at the time of first diagnosis and progression. With a median follow-up of 3.7 years (range: 1.1-12.0 years), the 3-year overall survival rate of the early relapsed patients was 67% (95%CI: 40 to 83). Patients with high levels of serum LDH both at initial diagnosis and at the time of first progression showed worse survival (P = 0.0001, Log-rank).