EXTRAMEDULLARY LEUKEMIA ADVERSELY AFFECTS HEMATOLOGIC COMPLETE REMISSION RATE AND OVERALL SURVIVAL IN PATIENTS WITH T(8-21)(Q22-Q22) - RESULTS FROM CANCER AND LEUKEMIA GROUP-B-8461

Purpose: To examine the prognostic significance of extramedullary leuk emia (EML) at presentation in patients with t(8;21)(q22;q22) karyotype . Patients and Methods: Consecutive patients with t(8;21) treated on C ancer and Leukemia Group 8 de novo acute myeloid leukemia (AML) treatm ent studies were examined for the presence of EML (granulocytic sarcom a, subcutaneous nodules, leukemia cutis, or meningeal leukemia) at ini tial presentation, Clinical features and outcome of t(8;21) patients w ith and without EML were compared. Results: Of 84 patients with t(8;21 ), eight (9.5%) had EML manifesting as granulocytic sarcoma (five para spinal, one breast, and one subcutaneous) or symptomatic meningeal leu kemia (n = 1). The pretreatment prognostic variables of t(8;21) patien ts with and without EML were similar. The hematologic complete remissi on (CR) rate for t(8;21) patients with EML was 50% versus 92% for thos e without EML (P = .006), The median CR duration for EML patients was 14.7 months. patients with EML had a shorter survival (P = 0.002, medi an 5.4 months versus 59.5 months). This poor outcome may relate to ina dequate local (radiation or intrathecal) therapy for patients with spi nal or meningeal EML, resulting in residual/recurrent EML following in duction chemotherapy (n = 2) or at relapse (n = 1) and permanent neuro logic deficits (n = 4). Only one of the EML patients received high-dos e cytarabine (HDAC) intensification; this is the only EML patient rema ining alive in CR. Conclusion: Patients with t(8;21) and EML have a lo w CR rate and overall survival, An aggressive local and systemic induc tion therapy should be considered for this patient subset, The effecti veness of HDAC intensification in t(8;21) patients with EML is uncerta in and warrants further study. (C) 1997 by American Society of Clinica l Oncology.