Alessandro Castello

Clinical Relevance of Bone Marrow Fibrosis and CD34-Positive Cell Clusters in Primary Myelodysplastic Syndromes

PURPOSE We studied bone marrow (BM) histologic abnormalities in myelodysplastic syndromes (MDS) classified according to WHO criteria to determine their clinical correlates and prognostic value. PATIENTS AND METHODS Three hundred one consecutive patients were retrospectively evaluated for BM fibrosis and CD34 immunoreactivity. Marrow fibrosis was assessed following the European consensus guidelines. RESULTS Moderate to severe BM fibrosis was detected in 17% of cases and was associated with multilineage dysplasia (P = .001), high transfusion requirement (P < .001), and poor-risk cytogenetics (P = .007). CD34+ cell clusters were found in 23% of patients and were associated with WHO categories with excess of blasts (P < .001) and poor-risk cytogenetics (P = .001). In multivariable analysis, BM fibrosis and presence of CD34+ cell clusters had independent negative impact on overall survival (P < .001 and P = .019, respectively) and leukemia-free survival (P < .001 and P = .004, respectively). A hierarchical clustering analysis identified three subsets of patients with distinct clinical features. One cluster consisted mainly of patients with BM fibrosis, multilineage dysplasia, and high transfusion requirement; these individuals had lower overall survival and leukemia-free survival (P = .001 and P < .001, respectively). Within patients stratified according to International Prognostic Scoring System and WHO classification-based Prognostic Scoring System categories, BM fibrosis involved a shift to a one-step more advanced risk group. CONCLUSION BM fibrosis identifies a distinct subgroup of MDS with multilineage dysplasia, high transfusion requirement, and poor prognosis and represents an independent prognostic factor that may be useful in clinical decision making. Furthermore, the presence of CD34+ cell clusters is an independent risk factor for progression to acute leukemia.

Myelofibrosis in chronic granulocytic leukaemia: clinicopathologic correlations and prognostic significance

Summary. We performed 221 marrow trephine biopsies in 139 patients with Ph1‐positive (Ph1‐+) chronic granulocytic leukaemia (CGL) in order to assess the incidence, degree and prognostic significance of marrow fibrosis (MF) at various stages of the disease. We also attempted to elucidate the relationship between development of MF and the various clinical and haematological features of CGL. A significant correlation was found between the amount of fibrosis (graded from 0 to 3) and the stage of CGL, indicating that major fibrotic changes are associated with accelerated or blastic disease. Survival studies performed to assess the prognostic significance of the various degrees of MF, showed a progressively worse life‐expectancy from grade 0 to grade 3 fibrosis. Multivariate regression analysis indicated Hb level, age, number of marrow megakaryocytes (MKs), time from diagnosis as the features most significantly correlated with the degree of MF. This study demonstrates that the natural history of CGL involves a progressive increase in reticulin deposition towards severe MF, although the rate of this progression varies widely. Monitoring changes of fibrosis with sequential biopsies could give a measure of the rate of progression of the disease and help in prognostic assessment of CGL patients. Our findings also confirm that among marrow features the number of MKs is the cytological variable most significantly correlated with MF.

Bone marrow histology in marginal zone B-cell lymphomas: correlation with clinical parameters and flow cytometry in 120 patients

BACKGROUND Among marginal zone lymphomas (MZLs), bone marrow (BM) involvement features are well established in the splenic marginal zone lymphoma (SMZL); few data are available for extranodal marginal zone lymphoma (EMZL) and nodal marginal zone lymphoma (NMZL). PATIENTS AND METHODS Incidence and patterns of histologic BM involvement are studied in 120 MZL patients (48 SMZL, 59 EMZL, 13 NMZL) at onset and during follow-up; relationships between clinical features, BM histology and flow cytometry (FC) are analyzed. RESULTS At diagnosis, BM involvement occurs in 90% SMZL, 22% EMZL and 54% NMZL (P<0.0001); at reevaluation, incidence raises to 96% in SMZL and 34% in EMZL. Concordance between histology and FC is found in 87% of cases; most discordant cases have positive histology but negative FC. SMZL and EMZL show a nodular BM infiltration; the interstitial pattern is frequent in NMZL (P<0.0001); sinusoidal localization is typical of SMZL, frequent in NMZL and occasional in EMZL (P=0.0001). Stage, leukemic disease, B symptoms, more than one extranodal involved site, splenomegaly, elevated beta2-microglobulin, serum monoclonal component, International Prognostic Index (IPI) and age-adjusted IPI are directly related to BM infiltration. CONCLUSIONS The different prevalence of BM involvement in MZL subtypes reflects their heterogeneous dissemination modalities; histology seems more sensible than FC to detect BM infiltration; development of BM involvement during follow-up is typical of EMZL.

Bone marrow microvessel density in chronic myeloproliferative disorders: a study of 115 patients with clinicopathological and molecular correlations

Philadelphia‐negative chronic myeloproliferative disorders (CMD) include polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). Angiogenesis is critical in the pathogenesis of PMF. We studied angiogenesis in 115 patients with CMD (23 PV, 24 ET, 46 PMF, 12 post‐PV and 10 post‐ET myelofibrosis) by assessment of microvessel density (MVD) in bone marrow (BM). Kruskall–Wallis analysis of variance showed that patients with PMF had significantly higher values of MVD than those with PV (P < 0·001), ET (P < 0·001) and controls (P < 0·001). Mann–Whitney U‐test demonstrated that patients with PMF at the prefibrotic stage had significantly higher MVD values than those with ET (P = 0·02). Patients with post‐PV myelofibrosis showed significantly higher MVD values than those with PV (P < 0·001), as did patients with post‐ET myelofibrosis compared with ET (P < 0·001). In patients with CMD, the multivariate generalized linear regression model showed that the JAK2 (V617F) mutational burden (P = 0·01), serum lactate dehydrogenase level (P = 0·003), and anaemia (P < 0·001) independently correlated with MVD. In summary, this study indicates that assessment of BM angiogenesis, as measured by MVD, may be a useful additional tool in the histopathological definition of CMD.

Interferon alpha‐2b as treatment for Philadelphia‐negative chronic myeloproliferative disorders with excessive thrombocytosis

Summary. We treated 32 patients with Ph1‐negative chronic myeloproliferative disorders (CMD) with excessive thrombocytosis with Interferon α‐2b (IFN α‐2b): 26 had essential thrombocythaemia, ET (18 previously untreated, eight pretreated); one thrombocythaemia after treatment for Hodgkins disease (HD); two thrombocythaemia associated with non‐Hodgkins lymphoma (NHL); three stage II idiopathic myelofibrosis (IM). IFN was given at daily doses of 1−4 × 106 IU. Twenty‐seven patients (84%) responded, 17 (53%) achieved complete haematologic response after a median time of 12 weeks, and 10 (31%) partial haematologic response. Median platelet levels declined in complete haematologic response patients from 1190 to 335 × 109/I. Normalization of megakaryocyte (MK) levels was observed in 8/17 complete haematologic response patients treated for 9–12 months, with decreased bone marrow (BM) cellularity. Side effects requiring dose reduction or discontinuation of treatment occurred in 28% of cases with IFN doses of 2 or 4 × 106 IU. After 1 year of continuous IFN treatment, responses were maintained with conventional chemotherapy or low‐dose IFN. This study demonstrates that IFN has definite therapeutic activity in CMD with excessive thrombocytosis. This biological agent, either alone or in combination with other antineoplastic treatment, may represent a new therapeutic approach for these disorders.

Clinicopathologic and immunologic characteristics of non‐Hodgkin's lymphomas presenting in the orbit. A report of eight cases

Of 325 consecutive cases of non‐Hodgkins malignant lymphomas, 8 patients (2.4%) showed orbital presentation. The clinicopathologic and immunologic analysis of the eight patients revealed characteristic biologic features. Despite the apparently isolated orbital presentation, all cases had subclinical systemic disease. Seven of the eight cases exhibited lymphoplasmacytic/cytoid features, with concurrent type II cryoglobulinemia in five of them. In addition, during their clinical course, five patients showed single or multiple subcutaneous nodules with the same histologic and immunologic pattern as the orbital tumor. This study demonstrates that most orbital lymphomas share particular clinicopathologic and immunologic features, suggesting an origin from a B‐cell subset with preferential homing to orbital tissues and subcutis.

Risk assessment in myelodysplastic syndromes: value of clinical, hematologic and bone marrow histologic findings at presentation.

We analyzed the prognostic value of clinical, hematologic and bone marrow (BM) histologic findings at presentation in 94 patients with myelodysplastic syndromes (MDS) (28 RA; 2 RARS; 34 RAEB; 6 CMML; 24 RAEB‐t). With survival as the dependent variable, stepwise multivariate analysis indicated as the prognostically most important factors among the MDS taken as a whole: latency from the first symptoms to diagnosis, age, and percentage of BM blasts. In each main MDS group the most unfavorable initial characteristics were: l)low Hb, no macro‐megaloblastosis, male sex for RA/RARS; 2) low Hb and low platelet levels for RAEB/CMML; 3) granuloblastic hyperplasia and high BM blastosis for RAEB‐t. Of the BM histologic parameters, only the percentage of blasts had significant prognostic value. Histologic assessment of BM blastosis, however, did not differ statistically from that based on cytologic examination of BM smears, so that marrow histology seemed not essential for initial prognostic assessment in MDS patients. The finding of abnormal localization of immature precursors (ALIP) in BM biopsies was associated with a negative trend without reaching statistical significance. Using four objective parameters of proven significance (age, Hb, platelets, and BM blasts) we devised a staging system of immediate clinical utility for prognostic stratification and risk‐adapted therapeutic choices.

Bone marrow and blood involvement by non-Hodgkin's lymphoma: a study of clinicopathologic correlations and prognostic significance in relationship to the Working Formulation.

In a series of 172 patients with non‐Hodgkins lymphoma (NHL) classified according to the Working Formulation (WF) the overall incidence of bone marrow infiltration (BM +) at diagnosis was 39%: 59% for low‐grade (LGML), 30% for intermediate‐grade (IGML), and 25% for high‐grade malignant lymphomas (HGML). The features most significantly correlated with the presence of BM + were a low grade of histological malignancy, the degree of splenomegaly and high values of LDH, while those correlated with the extent of BM+ were a non‐focal pattern of BM disease, the presence of blood involvement at diagnosis, and the degree of BM fibrosis. Blood involvement was detected at diagnosis in 13% of patients, and a further 16% developed a leukemic phase during the course of the disease. Blood involvement correlated significantly with splenomegaly, bulky disease, advanced clinical stage, and extent of BM +. The presence of BM infiltration ‘per se’ at diagnosis did not significantly affect prognosis. However, the extent of BM disease was correlated with a poorer outcome in IGML and HGML patients. Regarding peripheral blood involvement, in LGML patients only late leukemic conversions were significantly associated with a worse prognosis. In patients with IGML and HGML, either initial or subsequent blood involvement was correlated with significantly poorer outcome.

Therapy of essential thrombocythemia with alpha-interferon: Results and prospects

Abstract: Conventional treatment of symptomatic essential thrombocythemia (ET) consists of long‐term administration of myelosuppressive cytotoxic agents which, although efficacious in most cases, are associated with leukemogenic potential. Alpha‐interferon (IFN) exerts a dose‐dependent inhibitory influence on thrombopoiesis through a direct antiproliferative effect on megakaryocytic precursors. Therefore, it may provide a biologic, potentially non‐mutagenic alternative to conventional cytotoxic treatments. At daily doses ranging from 1 to 5 M.U., alpha‐IFN is efficacious in inducing a hematologic response in most patients with ET. Response to IFN is a gradual process. The median time to hematologic response varies from 1 to 3 months and a significant proportion of patients reach and maintain normal platelet counts with low doses (1–3 M.U./d). Normalization of marrow megakaryocytosis requires longer treatment (9–12 months). Also patients resistant to cytotoxic drugs may respond to alpha‐IFN, suggesting a lack of cross‐resistance between the two treatment modalities. Side‐effects, although not severe, represents a limit to the administration of adequate doses of IFN in about 25% of cases. Once hematologic response has been obtained, both low‐dose IFN and cytotoxic drugs are effective as maintenance. The full potentialities of alpha‐IFN in ET in combination with cytotoxic drugs or with other cytokines need to be further investigated.

Bone changes of mucolipidosis II at different ages : postmortem study of three cases

Bone changes are a constant feature of mucolipidosis II, with striking differences between newborns and older children. Intracellular, membrane-bound vacuoles were found in the chondrocytes, osteoblasts, osteocytes, and stromal fibroblasts of three affected children. Osteoclasts and marrow cells were unaffected. Ricketslike lesions were present at birth in the two younger cases, whereas signs of high bone turnover and defective calcification were no longer present in the older child. Severe abnormalities of the metaphyseal plate with the loss of normal cartilage architecture and the absence of endochondral ossification were the major changes in this age group.