Significance of myelofibrosis in early chronic-phase, chronic myelogenous leukemia on imatinib mesylate therapy.
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.
Kantarjian
Hagop M
HM
Department of Leukemia, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA. hkantarj@mdanderson.org
Bueso-Ramos
Carlos E
CE
Talpaz
Moshe
M
O'Brien
Susan
S
Giles
Francis
F
Faderl
Stefan
S
Wierda
William
W
Rios
Mary Beth
MB
Shan
Jianqin
J
Cortes
Jorge
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001549:Benzamides; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D015466:Leukemia, Myeloid, Chronic-Phase / Q000150:complications / Q000188:drug therapy* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use*; D055728:Primary Myelofibrosis / Q000188:drug therapy* / Q000209:etiology; D011379:Prognosis; D011743:Pyrimidines / Q000627:therapeutic use*; D016019:Survival Analysis
D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate