[Biologic aspects and clinical use of granulocyte growth factor]. / Aspetti biologici e impiego clinico del fattore di crescita granulocitario.

Granulocyte colony stimulating factors (G-CSF) has a wide spectrum of action: it stimulates proliferation and differentiation of granulocyte-macrophage progenitors, it promotes the chemotactic activity of monocytes and granulocytes and it develops the antibody-dependent cytotoxicity of neutrophils. In vivo G-CSF induces leucocytosis and it hastens the granulocyte recovery after chemio-radiotherapy. So it has been used in many pathologies: aplastic anaemia, AIDS in treatment with antiviral drugs, myelodysplastic syndromes, acute leukemias and solid tumors. If G-CSF is administered after chemotherapy, both in acute leukemias and in solid tumors, it reduces the duration of neutropenia and the number of febrile episodes so that it is possible to give the whole therapy at the planned dosage with no delay. However G-CSF does not modify the incidence of complete remissions and the overall survival. G-CSF allowed the increase of dose-intensity in chemoresistent neoplasms even if this therapy is always complicated by a heavy extrahaematological toxicity. Moreover G-CSF shortens the total duration of neutropenia after autologous or allogenic bone marrow and peripheral stem cell transplantation even if the appearance of the first neutrophil is not accelerated.

[Idiopathic myelofibrosis. Main pathogenetic, prognostic and therapeutic aspects]. / Mielofibrosi idiopatica. Principali aspetti patogenetici, prognostici e terapeutici.

Primary myelofibrosis is a complex disorder characterized by bone marrow fibrosis with no apparent cause. It is known in literature under a wide number of terms, reflecting the variety of clinical features and the different pathogenetic hypotheses. In most cases it is plain that marrow fibrosis is secondary to a clonal myeloproliferative disorder and, in particular, to the presence of abnormal megakaryocytes secreting (MKDGF/PDGF); but probably some other growth factors synthesized by megakaryocytes and contained in platelet alpha-granules are involved. The molecular event that determines the advantage of the clonal growth is, at present, unknown, and the pathogenetic importance of some chromosome anomalies is still under discussion. Over the last years, besides megakaryocyte dysplasia, several fibrogenetic mechanisms such as a bone marrow immune damage have been taken into consideration. Studies on prognostic factors regarding the main clinical, hematological and histological parameters have given conflicting results, because of low incidence of the disease, different criteria used for the diagnosis, and different terms of the clinic presentation of the pathology. Although a great deal of progress has been made in terms of pathogenetic mechanisms, a lot of questions must be still definitively settled, further in depth studies still have to go into many matters.

Primary myelofibrosis: a detailed statistical analysis of the clinicopathological variables influencing survival.

In the present study we analyzed the prognostic significance of several clinical, hematological, and histological parameters recorded at diagnosis in a consecutive series of 72 patients with primary myelofibrosis (PMF). Univariate analysis showed that the most significant indicators of poor survival were the following: age greater than 60, splenomegaly, anemia (hemoglobin > 10 g/dl), leukopenia (WBC < 4 x 10(9)/l or leukocytosis > 14 x 10(9)/l), and any of these histological features: adipose tissue and megakaryocyte reduction, prominent osteoblastic rims along the trabecular bone, presence of peritrabecular megakaryocytes (Mk), absence of normal or giant Mk. The multivariate analysis showed that only the level of hemoglobin and the presence of both normal Mk and fever independently influenced the prognosis. These parameters were used to set up a prognostic scoring system, allowing a feasible prognosis to be made for each patient at the time of diagnosis and identifying those patients in urgent need of new therapeutic approaches.

Antibodies against terminal galactosyl alpha(1-3) galactose epitopes in patients with idiopathic myelofibrosis.

Sera from patients with myelofibrosis were analysed for circulating antibodies against an antigenic determinant characterized by two molecules of galactose in alpha 1-3 linkage (anti-Gal antibodies). 50% of patients were found to have values above the 90th percentile of the values of control sera chosen as a cut-off. The median level of the antibodies was significantly higher than the value detected in normal controls, but no difference could be found between patients with idiopathic myelofibrosis and those with myelofibrosis associated to a chronic myeloproliferative disorder. Anti-Gal antibodies were found to correlate with disease activity and with platelet count whereas no correlation was detected with other haematological parameters. Furthermore, for evaluation of disease activity, determination of serum anti-Gal antibodies was a sensitive and specific parameter. We conclude that humoral immunity against Gal alpha 1-3Gal may provide a sensitive tool to detect disease activity in patients with idiopathic myelofibrosis and may be important for understanding its pathogenesis.

[Peripheral neuropathy associated with Castleman's lymphoma]. / Neuropatia periferica associata a linfoma di Castleman.

Castleman's lymphoma is a rare clinicopathological entity and is often difficult to classify nosographically. From the histopathological point of view two variants are recognized, one hyalino-vascular and one plasma cellular. Moreover Castleman's lymphoma may be multifocal or unifocal (located within the thorax in 70% of patients). The plasma cellular variant is often associated with systemic symptoms such as fever, sweating, organomegaly, polyneuropathy, and mono- or polyclonal gammopathy. We describe a rare case of unifocal, plasma cellular-type Castleman's lymphoma located in the mediastinum, asymptomatic at onset but later dominated by neurological symptoms (chronic isolated polyneuropathy whose clinical expression was predominantly motor). A brief review is presented of the main clinico-histological characteristics of Castleman's lymphoma together with some hypotheses about the pathogenesis of the associated neuropathy.

[The soluble IL-2 receptor in malignant hemopathies]. / Il recettore solubile dell'IL-2 nelle emopatie maligne.

The increase in the serum levels of the IL-2 receptors is due to its release both in vivo and in vitro from activated cells or neoplastic cells expressing it constitutively. The diagnostic, prognostic and physiopathologic significance of the sIL-2R was investigated by testing the serum of 271 haemopathic patients in various stages of the disease. In HCL the elevated sIL-2R level has a diagnostic value. In HD the sIL-2R level appears to be directly correlated with the extent of the disease and is equally important in the follow up of patients with HCL, NHL, HD, AL and MDS, where the serum level of the soluble receptor is usually associated with the biological and clinical activity of the disease. Unlike other B lymphoproliferations, patients with Multiple Myeloma on average show only slightly elevated levels of soluble receptor with no significant differences related to the stage or evolution. As for the chronic myeloproliferative disorders, we found only slightly elevated values in ET and PV, with frankly pathological values in CML during a blastic crisis or in the accelerated phase and in MFI during the clinically active phase of the disease.