A prognostic classification of myelofibrosis with myeloid metaplasia

Abstract

The dependence of survival time on a set of prognostic factors was explored by means of Cox's regression model in 137 cases of myelofibrosis with myeloid metaplasia (MMM). The following parameters recorded at diagnosis proved to be important independent indicators of a poor prognosis: a higher value for age, a lower value for Hb concentration, a higher value for immature myeloid cells in peripheral blood (IMC), a lower value for total erythroid iron turnover (TEIT), and a bone marrow red cell aplasia (RCA). A prognostic classification tree was constructed whose terminal nodes (risk groups), described by simple logical conditions upon important indicators, were characterized by significantly different expected survival. The two extreme risk groups lend themselves to a simple, but complete description. The low-risk group (19.7% of the sample) comprises cases who had the diagnosis of MMM before age 45 and a number of IMC constantly lower than 24%. The actuarial proportion of patients surviving at 15 years was 100%. The high-risk group (29.9% of cases) comprises patients with age greater than 45 and Hb lower than 13 g/dl, associated with RCA, or with a relatively decreased erythropoiesis (TEIT lower than 2 times the normal) or with IMC greater than 24%. Seven out of the 11 who died within this group developed blastic crisis. Median survival time of the group was 69 months.

Cytogenetic and Molecular Genetic Aspects of Idiopathic Myelofibrosis

“…Chromosomal abnormalities, for example, have been associated with a shorter survival in several recent studies [33, 34, 38], in contrast to earlier reports [63, 64]. Anaemia, however, has been consistently associated with a shorter survival [34, 38, 65, 66]and forms the basis of several useful prognostic schemes [34, 38]. In one prognostic model the median survival of patients below the age of 69 years who did not have either anaemia (haemoglobin <10 g/dl) or an abnormal karyotype was 180 months, compared to 22 months for the age-matched cohort with both anaemia and abnormal cytogenetics [34].…”

Prognostic impact of apoptosis and proliferation in idiopathic (primary) myelofibrosis

“…Following the ISEL-procedure, apoptotic nuclei (c,d) reveal a black reaction (arrows), indicating programmed cell death. a,b x350; c,d x870 anemia [3,5,10,17,18,21,26,27,29,31,42,43], age at diagnosis [3,5,10,21,29,42], peripheral blood precursors [3,5,43], and platelet and leukocyte counts [10,21,29,43] were found to exert a prognostic impact in IMF. Furthermore, in recently published series cytogenetic abnormalities were additional indicators of a worsening prognosis [7,10,29].…”

“…A wealth of data has been accumulated in recent years about the extreme heterogeneity of survival patterns in IMF [11] when univariate [1,17,18,23,34] and multivariate [3,10,29,31,42,43] evaluation methods are applied to identify independent prognostic features. However, this large body of predictive data has been partly obscured by relatively small study populations and illdefined series with altering diagnostic criteria.…”

“…Furthermore, only a few series included early hypercellular and prefibrotic stages [21,38]. Most often, age [3,5,10,21,29], degree of anemia [3,5,10,17,18,21,26,27,29,31,43], leukocyte and platelet counts [10,21,27,29,43], and extent of bone marrow fibrosis [16][17][18] were reported to influence survival. Additionally, in recently published series cytogenetic abnormalities were associated with a worsening of prognosis [7,10,29].…”

Hematopoietic cell transplantation for chronic myeloproliferative disorders

“…Chronic myeloproliferative disorders are predominantly disorders of older patients with a median age at diagnosis of 55-65 years [2,24]. The incidence is estimated at 0.5 cases/100,000 individuals/year.…”