The course of disease in patients with myelofibrosis is highly variable, with survival ranging from few months to many years. Several prognostic models have been established, with the LILLE score now most commonly used. However, in recent series, the latter scoring system repeatedly failed to discriminate patients with intermediate and poor prognosis. In the present study, we re-evaluated previous prognostic models in a separate patient population. We have studied 107 patients with myelofibrosis and correlated clinical parameters at the time of diagnosis with survival. Previous scoring systems were applied to allocate patients to subgroups with distinct prognosis. Most previous scoring systems failed to clearly discriminate an intermediate and poor prognostic group. By contrast, age and hemoglobin level emerged as most significant parameters in multivariate analysis. By allocating one risk point each for hemoglobin < 10 g/dl and age >60 years, three subgroups of patients with distinct prognosis could be identified in our cohort. The overall model and the difference between each of the subgroups were statistically significant in a training group, a test group, the overall cohort of patients and the group of patients with chronic idiopathic myelofibrosis. In summary, we propose an alternative prognostic model for patients with myelofibrosis that reliably identifies three groups of patients with highly different outcome. This is in contrast to previous prognostic scores, in which the poor prognosis group was often very small and/or could not be consistently differentiated from patients with an intermediate prognosis.

BACKGROUND. in chronic myelofibrosis (MF), distinct recurrent cytogenetic aberrations have been identified but their true prognostic relevance remains uncertain. In this disease, cytogenetic studies as assessed by conventional metaphase karyo-typing are limited due to the inherent difficulties in obtaining adequate bone marrow aspirates and the low proliferative capacity of the clonal cells. Interphase fluorescent in situ hybridization (FISH) can partly overcome these limitations and increase the sensitivity of cytogenetic assessment in MF.METHODS. We retrospectively analyzed formalin-fixed, paraffin embedded bone marrow sections of 107 MF patients by FISH and correlated cytogenetic findings with clinical presentation and survival.RESULTS. Chromosomal aberrations were detected in 56% of patients, with 20q- (24.3%) and 13q- (16.8%) being the most frequent ones. Importantly, cytogenetic abnormalities were found in 8/17 patients displaying a normal karyotype as assessed by conventional cytogenetics.CONCLUSIONS. Cytogenetic abnormalities in patients with MF can be detected reliably using FISH. Rare abnormalities confer an adverse outcome, but the main recurrent chromosomal aberrations do not correlate with clinical features and prognosis.

Several studies suggest a poor prognosis for patients with myelofibrosis (MF) with an abnormal karyotype, but the prognostic impact of specific cytogenetic lesions is difficult to define.[1][1] Using conventional cytogenetics, Tefferi et al were able to demonstrate that +8 and 12p- were associated

Pulmonary MALT lymphoma is a rare disease entity and generally follows an indolent clinical course. Due to scarce information from randomized prospective trials, no standardized therapy protocols exist. Besides irradiation and chemotherapy, novel biological agents such as the anti CD20-antibody rituximab and thalidomide constitute a promising new approach. In this report we demonstrate the case of a 52-year-old male patient with extra-intestinal MALT lymphoma of the lung. After 10 months of treatment with low dose thalidomide (100mg/d), very good partial response of the intrapulmonary lesions was achieved.

Neutrophil PRV-1 mRNA is overexpressed in nearly all patients with polycythemia vera (PV) and discriminates PV from secondary polycythemia. In addition, 40– 50% of patients with essential thrombocythemia (ET) and chronic idiopathic myelofibrosis (cIMF) overexpress PRV-1. PRV-1 positive ET patients carry a significantly higher risk of thromboembolic complications compared to PRV-1 negative patients. In addition, PRV-1 overexpression and the growth of endogenous erythroid colonies (EECs) are closely correlated in ET patients. A significant proportion of PRV-1 positive/EEC positive ET patients develop PV during follow up, while this has not been observed in PRV-1/EEC negative patients. In contrast, PRV-1 and EEC expression in cIMF has not been analysed in the context of clinical course. We therefore determined PRV-1 expression and EEC formation in a cohort of 21 cIMF patients and compared clinical parameters and risk scores between PRV-1 positive and negative patients. Blood samples were drawn from 21 patients (m/f: 12/9; age: 72, 39–79 years); peripheral blood MNCs and granulocytes were purified concurrently. The former were assayed for EEC growth while the latter were used to measure PRV-1 expression. Diagnosis of cIMF according to the WHO criteria was confirmed by histopathology. The median time from diagnosis was 3 years (0,5–16,5 years). At the time of investigation six patients were receiving imatinib in the setting of a phase II trial and four received hydroxyurea. The nonparametric Wilcoxon rank sum test was used to compare hematocrit, WBC and platelet counts, LDH-levels, age as well as the Cologne risk score between groups. Fourteen of the 21 patients (67%) overexpressed PRV-1. Eight of these also showed autonomous EEC growth. Three of the remaining PRV-1 positive patients were receiving imatinib at the time of analysis and colony growth was suppressed both in the presence and absence of Epo. In the remaining three PRV-1 positive patients EEC growth was not evaluable due to lack of growth with Epo. Of the seven PRV-1 negative IMF patients six did not give rise to EECs, and one was not evaluable due to lack of growth in the presence of Epo. Hence, as previously reported in ET and in five cIMF patients, we find a close correlation between PRV-1 overexpression and EEC formation in our cohort of cIMF patients. These data support the hypothesis that two distinct molecular alterations, one leading to PRV-1 overexpression and EEC formation, the other not, can give rise to the clinical symptoms of cIMF. Because the EEC assay was informative in fewer patients than the PRV-1 assay and because the parameters are closely correlated, patients were classified by PRV-1 expression and the clinical course compared between the two groups. There was no difference between PRV-1 positive and negative patients with respect to WBC- and PLT counts, LDH-levels or highest hematocrit recorded during follow up. In contrast, PRV-1 positive cIMF patients displayed a trend to a poorer Cologne risk score (P=0.095). Thus, PRV-1 overexpressing CIMF may comprise a subgroup of patients with a poorer risk profile. Due to the relatively small sample size the statistical power of our study is limited and verification of the results in a larger sample is required.

SummaryPatients with polycythemia vera (PV) have an increased risk for the development of thrombohemorrhagic complications. The pathogenesis of these complications is still unclear.An important role in vascular disease has recently been attributed to osteoprotegerin (OPG). It has been shown that various tissues of the cardiovascular system produce OPG, and there is growing evidence of an association between elevated serum OPG levels and cardiovascular morbidity.We evaluated if OPG was associated with an increased risk of venous thrombosis or bleeding complications in a cohort of 114 PV patients.The analysis consisted of a retrospective and a prospective part. In the retrospective univariate analysis,a one unit change in OPG caused the odds of venous thrombosis to increase by 40% (p=0.005) and the odds of bleeding to increase by 52% (p=0.001). Multivariate analysis only slightly attenuated the association to 33% (p=0.03) and 37% (p=0.013) for venous thrombosis and bleeding, respectively. OPG was also related to the development of the combined outcome of venous thrombosis and bleeding in the prospective analysis (log-rank-test: p=0.017).This is the first report that links the occurrence of venous thrombosis or bleeding to elevated OPG levels.

9611 Background: An abnormal karyotype has been correlated with poor prognosis in myelofibrosis with myeloid metaplasia (MMM) in several recent studies. This may be due to an increased proliferative index in these cases. However, conventional cytogenetics is usually hampered by the difficulty of obtaining sufficient numbers of analyzable metaphases from bone marrow aspirates in MMM. This obstacle can be overcome by fluorescence in situ hybridization (FISH), which can be performed on interphase nuclei from archival material. Methods: In this study, the bone marrow of 107 patients with MMM was analyzed using FISH and chromosomal probes 7cen, 7q, 8cen, 20q, 11cen, 12p, 13q, 17cen, 17p, 21q. Cases with myelodysplastic features or a known bcr/abl translocation were excluded from analysis. The prognostic impact of individual cytogenetic lesions on survival was evaluated using multivariate analysis. Results: In univariate analysis, -7/7q- was significantly associated with inferior outcome (median survival 99 vs. 25 months, p<0.001). This abnormality remained significant in a multivariate analysis including all cytogenetic parameters, our own myelofibrosis prognostic index (MPI) and the LILLE prognostic score. When a cytogenetic risk indicator (CPI), based on several cytogenetic variables, was used, patients were clearly divided into two groups with a significantly distinct outcome. Conclusions: Detection of loss of 7/7q by FISH was found to be significantly associated with inferior outcome in MMM. Multivariate analysis including established prognostic factors identified deletion of 7/7q as independent prognostic factor in patients with MMM. By using cytogenetic findings only, patients can be allocated into poor and good risk groups. No significant financial relationships to disclose.

6621 Background: Several prognostic models for patients with myelofibrosis with myeloid metaplasia (MMM) have been developed, with the LILLE score1 now most commonly used. The latter and other previous scoring systems, however, showed limited power to consistently separate patients with intermediate and poor prognosis. Methods: We have studied 107 patients with MMM (median age 68, range 24–87) and correlated clinical parameters at the time of diagnosis with survival by multivariate analysis. Results: Hemoglobin and age at diagnosis was found to be significantly associated with prognosis (p<0.1x10-5, p<0.1x10-6, respectively). These data were used to establish a prognostic index (myelofibrosis prognostic index, MPI) in a training group. One risk point was allotted for each Hb<10 g/dl and age> 60 years, respectively. The relevance of the MPI was confirmed in the test group and in the overall cohort of patients (Table 1). Median survival was not reached in the good prognosis group and was 64 and 34 in the intermediate and poor group respectively (p<0.1x10-6) . Next, previously published prognostic models were evaluated in our cohort of patients. The application of the LILLE model did not result in sufficient separation of patients with an intermediate or poor prognosis (Table 1). Conclusions: We have established a new, simple prognostic index (MPI) which discriminates three prognostic groups with highly significant different survival. Our data also confirm a previous report by Kvasnicka et al. who have shown the prognostic relevance of age and hemoglobin before, but used in addition leukocyte and platelet counts for separation of patients into different prognostic subgroups. No significant financial relationships to disclose.

Remarkable results of the treatment of refractory multiple myeloma with thalidomide have been reported. In most preceding studies, the given thalidomide dose was escalated to a maximum tolerated dose of up to 800 mg/d. The frequency of adverse effects correlates with dose intensity. Since a significant gain of therapeutic effects could not be observed as thalidomide dosage was escalated, the optimal dose of thalidomide remains to be determined. We report the results of a study with low dose thalidomide (median administered dose 100 mg/d, range 50-400 mg/d). Twenty-four relapsed (n = 19) or resistant (n = 5) multiple myeloma patients were included in the study. Twelve patients (50%) received thalidomide as monotherapy, 8 patients (33%) received a combination of thalidomide and dexamethasone (every 4 weeks 40 mg/day for 4 days) and 4 patients (17%) who were resistant to vincristine, doxorubicin, dexamethasone (VAD) received VAD combined with thalidomide. Overall, a response was observed in 12 patients (50%). Of the 12 patients treated with low dose thalidomide alone 5 (42%) responded, of the 8 patients who received a combination of thalidomide and dexamethasone 5 (63%) responded and of the 4 patients who had thalidomide in addition to VAD 2 patients (50%) responded. In 3 patients, thalidomide treatment had to be discontinued because of side effects and 1 patient died before response could be assessed. We conclude that low dose thalidomide is an effective and safe rescue therapy in relapsing or refractory multiple myeloma. Response to thalidomide might be dependent on prognostic parameters and tumor burden. To answer these questions larger prospective studies are necessary.

Multiple myeloma (MM) is characterized by infiltration of bone marrow with a clone of neoplastic plasma cells. Impaired hematopoiesis and reduced production of functional immunoglobulins, as well as the induction of pathognomonic osteolytic lesions primarily contribute to the morbidity of patients with MM. Conventional chemotherapy is the treatment of choice for older patients, whereas those under 60 years benefit significantly from high-dose therapy followed by stem-cell rescue. The use of tandem transplantation, developed to further escalate the conditioning dose, has achieved additional improvement in survival. Interferon-α and glucocorticoids are effective as maintenance measures in MM but remain controversial because of their associated high costs and considerable toxicity. The resurrection of an old drug, thalidomide, for the therapy of MM and the development of potent immunomodulatory derivatives are highly promising new treatments that target MM cell-host interactions and the bone-marrow microenvironment, as well as the myeloma cell itself. The importance of the use of bisphosphonates for the prevention or amelioration of skeletal complications and hypercalcemia is well established. New generations of bisphosphonates show potent antitumor activity, again emphasising the importance of targeting the microenvironment of the plasma-cell clone.

Arsenic containing treatments have a history of over two millenniums. Recently, arsenic trioxide (As 2 O 3 ) has been introduced into the treatment of both de novo and relapsed acute promyelocytic leukemia (APL), with remarkable clinical success. Several investigations using both freshly isolated APL blast cells as well as APL-derived tumor cell lines have shown that the main mechanism by which As 2 O 3 exerts its antileukemic activity in APL is induction of apoptosis in the leukemic cell population. Recently, it has become evident that the apoptotic effects of As 2 O 3 are not restricted to APL cells but may also be observed in malignant cells of non-APL origin. In the present review, history, current clinical use as well as future perspectives of As 2 O 3 therapy in both hematologic and solid malignancies are discussed, with special emphasis being put on the potential future role of As 2 O 3 in the treatment of non-APL tumors. Of particular importance, enhancing agents suited to increase As 2 O 3 -sensitivity in less sensitive tumors (e.g. ascorbic acid) are also addressed.