Significance of myelofibrosis in early chronic‐phase, chronic myelogenous leukemia on imatinib mesylate therapy

• Published in: Cancer 2005-08, Vol.104 (4), p.777-780
• Main Authors: Kantarjian, Hagop M., Bueso‐Ramos, Carlos E., Talpaz, Moshe, O'Brien, Susan, Giles, Francis, Faderl, Stefan, Wierda, William, Rios, Mary Beth, Shan, Jianqin, Cortes, Jorge
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Antineoplastic Agents - therapeutic use; Benzamides; Biological and medical sciences; chronic myelogenous leukemia; Female; Hematologic and hematopoietic diseases; Humans; Imatinib Mesylate; Leukemia, Myeloid, Chronic-Phase - complications; Leukemia, Myeloid, Chronic-Phase - drug therapy; Leukemia, Myeloid, Chronic-Phase - mortality; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Male; Medical sciences; Middle Aged; myelofibrosis; Philadelphia chromosome; Piperazines - therapeutic use; positive chronic phase; Primary Myelofibrosis - drug therapy; Primary Myelofibrosis - etiology; Prognosis; prognostic significance; Pyrimidines - therapeutic use; Survival Analysis; Tumors
• ISSN: 0008-543X; 1097-0142
• DOI: 10.1002/cncr.21235

BACKGROUND Myelofibrosis is associated historically with a poor prognosis in patients with chronic myelogenous leukemia (CML). Its significance in the recent era of effective therapy with imatinib mesylate is unknown. METHODS The current study evaluated the significance of the degree of pretreatment myelofibrosis on response and survival with imatinib therapy in patients with newly diagnosed CML. The study group comprised 198 patients with newly diagnosed Philadelphia chromosome‐positive, chronic‐phase CML treated with imatinib mesylate therapy. They were analyzed for the prognostic significance of bone marrow reticulin fibrosis. RESULTS Severe reticulin (Grade 3–4) fibrosis was observed in 75 patients (38%): Grade 3 in 46 (23%) patients and Grade 4 in 29 (15%) patients. There was a trend towards a lower incidence of a complete cytogenetic response in patients with Grade 4 reticulin fibrosis (76% vs. 89%; P = 0.07), and a significantly worse survival (estimated 3‐year survival rate of 87% vs. 97%; P = 0.04). CONCLUSIONS Although the prognostic significance of severe reticulin fibrosis in patients with newly diagnosed CML receiving imatinib therapy was better, 15% of patients with Grade 4 reticulin fibrosis still had a worse outcome. Cancer 2005. © 2005 American Cancer Society. The significance of severe (Grade 3 or 4) reticulin fibrosis was evaluated in 198 patients with newly diagnosed chronic myelogenous leukemia (CML) receiving imatinib therapy. Fifteen percent of patients with Grade 4 reticulin fibrosis still had a trend for a lower incidence of a complete cytogenetic response (76% vs. 89%; P = 0.07) and a worse estimated 3‐year survival rate (87% vs. 98%; P = 0.04) compared with patients with CML with less severe bone marrow fibrosis.