Gaucher Disease or Acid Sphingomyelinase Deficiency? The Importance of Differential Diagnosis

Background: Gaucher disease is a lysosomal storage disorder caused by functional glucocerebrosidase enzyme deficiency. Hepatosplenomegaly and hematological complications are found in both Gaucher disease and Acid Sphingomyelinase Deficiency, which is caused by acid sphingomyelinase dysfunction. The possible overlap in clinical presentation can cause diagnostic errors in differential diagnosis. For this reason, in patients with an initial clinical suspicion of Gaucher disease, we aimed to carry out a parallel screening of acid sphingomyelinase and glucocerebrosidase. Methods: Peripheral blood samples of 627 patients were collected, and enzymatic activity analysis was performed on both glucocerebrosidase and acid sphingomyelinase. The specific gene was studied in samples with null or reduced enzymatic activity. Specific molecular biomarkers helped to achieve the correct diagnosis. Results: In 98.7% of patients, normal values of glucocerebrosidase activity excluded Gaucher disease. In 8 of 627 patients (1.3%), the glucocerebrosidase enzymatic activity assay was below the normal range, so genetic GBA1 analysis confirmed the enzymatic defect. Three patients (0.5%) had normal glucocerebrosidase activity, so they were not affected by Gaucher disease, and showed decreased acid sphingomyelinase activity. SMPD1 gene mutations responsible for Acid Sphingomyelinase Deficiency were found. The levels of specific biomarkers found in these patients further strengthened the genetic data. Conclusions: Our results suggest that in the presence of typical signs and symptoms of Gaucher disease, Acid Sphingomyelinase Deficiency should be considered. For this reason, the presence of hepatosplenomegaly, thrombocytopenia, leukocytopenia, and anemia should alert clinicians to analyze both enzymes by a combined screening. Today, enzyme replacement therapy is available for the treatment of both pathologies; therefore, prompt diagnosis is essential for patients to start accurate treatment and to avoid diagnostic delay.

Determinants of frontline tyrosine kinase inhibitor choice for patients with chronic-phase chronic myeloid leukemia: A study from the Registro Italiano LMC and Campus CML

BACKGROUND

Imatinib, dasatinib, and nilotinib are tyrosine kinase inhibitors (TKIs) approved in Italy for frontline treatment of chronic-phase chronic myeloid leukemia (CP-CML). The choice of TKI is based on a combined evaluation of the patient's and the disease characteristics. The aim of this study was to analyze the use of frontline TKI therapy in an unselected cohort of Italian patients with CP-CML to correlate the choice with the patient's features.

METHODS

A total of 1967 patients with CP-CML diagnosed between 2012 and 2019 at 36 centers throughout Italy were retrospectively evaluated; 1089 patients (55.4%) received imatinib and 878 patients (44.6%) received a second-generation (2G) TKI.

RESULTS

Second-generation TKIs were chosen for most patients aged <45 years (69.2%), whereas imatinib was used in 76.7% of patients aged >65 years (p < .001). There was a predominant use of imatinib in intermediate/high European long-term survival risk patients (60.0%/66.0% vs. 49.7% in low-risk patients) and a limited use of 2G-TKIs in patients with comorbidities such as hypertension, diabetes, chronic obstructive pulmonary disease, previous neoplasms, ischemic heart disease, or stroke and in those with >3 concomitant drugs. We observed a greater use of imatinib (61.1%) in patients diagnosed in 2018-2019 compared to 2012-2017 (53.2%; p = .002). In multivariable analysis, factors correlated with imatinib use were age > 65 years, spleen size, the presence of comorbidities, and ≥3 concomitant medications.

CONCLUSIONS

This observational study of almost 2000 cases of CML shows that imatinib is the frontline drug of choice in 55% of Italian patients with CP-CML, with 2G-TKIs prevalently used in younger patients and in those with no concomitant clinical conditions. Introduction of the generic formulation in 2018 seems to have fostered imatinib use.

Treatment-Free Remission in Chronic Myeloid Leukemia Patients Treated With Low-Dose TKIs: A Feasible Option Also in the Real-Life. A Campus CML Study

Treatment-free remission (TFR) has become a primary therapeutic goal in CML and is also considered feasible by international guidelines. TKIs dose reduction is often used in real-life practice to reduce adverse events, although its impact on TFR is still a matter of debate. This study aimed to explore the attitude of Italian hematologists towards prescribing TKIs at reduced doses and its impact on TFR. In September 2020, a questionnaire was sent to 54 hematology centers in Italy participating to the Campus CML network. For each patient, data on the main disease characteristics were collected. Most of the hematologists involved (64.4%) believed that low-dose TKIs should not influence TFR. Indeed, this approach was offered to 194 patients. At the time of TFR, all but 3 patients had already achieved a DMR, with a median duration of 61.0 months. After a median follow-up of 29.2 months, 138 (71.1%) patients were still in TFR. Interestingly, TFR outcome was not impaired by any of the variables examined, including sex, risk scores, BCR-ABL1 transcript types, previous interferon, type and number of TKIs used before treatment cessation, degree of DMR or median duration of TKIs therapy. On the contrary, TFR was significantly better after dose reduction due to AEs; furthermore, patients with a longer DMR duration showed a trend towards prolonged TFR. This survey indicates that low-dose TKI treatment is an important reality. While one third of Italian hematologists still had some uncertainties on TFR feasibility after using reduced doses of TKIs outside of clinical trials, TFR has often been considered a safe option even in patients treated with low-dose TKIs in the real-life setting. It should be noted that only 28.9% of our cases had a molecular recurrence, less than reported during standard dose treatment. Consequently, TFR is not impaired using low-dose TKIs.

COVID-19 infection in chronic myeloid leukaemia after one year of the pandemic in Italy. A Campus CML report

Limited information is available on the impact of the COVID-19 pandemic on the management of chronic myeloid leukaemia (CML). The Campus CML network collected retrospective information on 8 665 CML patients followed at 46 centres throughout Italy during the pandemic between February 2020 and January 2021. Within this cohort, we recorded 217 SARS-CoV-2-positive patients (2·5%). Most patients (57%) were diagnosed as having SARS-CoV-2 infection during the second peak of the pandemic (September 2020 to January 2021). The majority (35%) was aged between 50 and 65 years with a male prevalence (73%). Fifty-six percent of patients presented concomitant comorbidities. The median time from CML diagnosis to SARS-CoV-2 infection was six years (three months to 18 years). Twenty-one patients (9·6%) required hospitalization without the need of respiratory assistance, 18 (8·2%) were hospitalized for respiratory assistance, 8 (3·6%) were admitted to an intensive care unit, while 170 (78%) were only quarantined. Twenty-three percent of patients discontinued tyrosine kinase inhibitor (TKI) therapy during the infection. Twelve patients died due to COVID-19 with a mortality rate of 5·5% in the positive cohort and of 0·13% in the whole cohort. We could also document sequelae caused by the SARS-CoV-2 infection and an impact of the pandemic on the overall management of CML patients.

Prognostic Factors for Overall Survival In Chronic Myeloid Leukemia Patients: A Multicentric Cohort Study by the Italian CML GIMEMA Network

An observational prospective study was conducted by the CML Italian network to analyze the role of baseline patient characteristics and first line treatments on overall survival and CML-related mortality in 1206 newly diagnosed CML patients, 608 treated with imatinib (IMA) and 598 with 2^nd generation tyrosine kinase inhibitors (2GTKI). IMA-treated patients were much older (median age 69 years, IQR 58-77) than the 2GTKI group (52, IQR 41-63) and had more comorbidities. Estimated 4-year overall survival of the entire cohort was 89% (95%CI 85.9-91.4). Overall, 73 patients (6.1%) died: 17 (2.8%) in the 2GTKI vs 56 (9.2%) in the IMA cohort (adjusted HR=0.50; 95% CI=0.26-0.94), but no differences were detected for CML-related mortality (10 (1.7%) vs 11 (1.8%) in the 2GTKIs vs IMA cohort (sHR=1.61; 0.52-4.96). The ELTS score was associated to CML mortality (high risk vs low, HR=9.67; 95%CI 2.94-31.74; p<0.001), while age (per year, HR=1.03; 95%CI 1.00-1.06; p=0.064), CCI (4-5 vs 2, HR=5.22; 95%CI 2.56-10.65; p<0.001), ELTS score (high risk vs low, HR=3.11; 95%CI 1.52-6.35, p=0.002) and 2GTKI vs IMA (HR=0.26; 95%CI 0.10-0.65, p=0.004) were associated to an increased risk of non-related CML mortality. The ELTS score showed a better discriminant ability than the Sokal score in all comparisons.

Adherence, persistence and efficacy of dasatinib and nilotinib in the treatment of patients resistant or intolerant to imatinib with chronic myeloid leukemia in chronic phase: an Italian multicenter study over two years in real life

BACKGROUND

The use of dasatinib and nilotinib in the treatment of patients with chronic myeloid leukemia represents a valid therapeutic option for patients resistant or intolerant to imatinib. In this multicentre study, adherence, persistence and efficacy in real life over two years of treatment were evaluated.

MATERIALS AND METHODS

Adherence to treatment was calculated as the ratio between the dose received and the prescribed dose. The dose received was calculated using pharmacy refill data. The persistence with treatment was calculated as the difference between the end and the beginning of the treatment. Efficacy was assigned as Progression-Free Survival (PFS) and Events-Free Survival (EFS) and represented through the Kaplan-Meier curve.

RESULTS

The number of patients analysed was 117, 70 treated with dasatinib and 47 with nilotinib. Adherence to treatment for dasatinib and nilotinib at two years was 0.91 and 0.82 respectively. Persistence at two years was 77% while the PFS was 92% for both drugs in the study.

CONCLUSION

Adherence to the treatment calculated over two years showed a superiority of dasatinib over nilotinib. Nevertheless, the efficacy in terms of PFS and EFS is superimposable between the two drugs in the study.

Ponatinib as second-line treatment in chronic phase chronic myeloid leukemia patients in real-life practice

Scarce information is available on the use of ponatinib as second-line treatment in chronic phase chronic myeloid leukemia (CP-CML) patients resistant and/or intolerant to prior tyrosine kinase inhibitor (TKI) therapy. We collected data from 29 CML patients, with a median age of 54 years (range 32-72). Eleven patients had received dasatinib, 15 patients received nilotinib, and 3 patients received imatinib as first-line treatment. Forty-five percent of patients started ponatinib for secondary resistance, 38% for primary resistance, 7% for severe intolerance associated to a molecular warning, 7% due to the presence of a T315I mutation, and 3% for severe intolerance. Ponatinib was started at a dose of 45 mg in 60% of patients, 30 mg in 38%, and 15 mg in 2% of patients. Overall, at a median follow-up of 12 months, 85% of treated patients improved the level of response as compared to baseline, with 10 patients achieving a deep molecular response (MR4-4.5). No thrombotic events were recorded. The dose was reduced during treatment in 2 patients due to intolerance and in 8 patients in order to reduce the cardiovascular risk. Ponatinib seems a valid second-line treatment option for chronic phase CML, in particular for patients who failed a front-line second-generation TKI due to BCR-ABL-independent mechanisms of resistance.

Assessment of the interlaboratory variability and robustness of JAK2V617F mutation assays: A study involving a consortium of 19 Italian laboratories

To date, a plenty of techniques for the detection of JAK2^V617F is used over different laboratories, with substantial differences in specificity and sensitivity. Therefore, to provide reliable and comparable results, the standardization of molecular techniques is mandatory.

A network of 19 centers was established to 1) evaluate the inter- and intra-laboratory variability in JAK2^V617F quantification, 2) identify the most robust assay for the standardization of the molecular test and 3) allow consistent interpretation of individual patient analysis results. The study was conceived in 3 different rounds, in which all centers had to blindly test DNA samples with different JAK2^V617F allele burden (AB) using both quantitative and qualitative assays.

The positivity of samples with an AB < 1% was not detected by qualitative assays. Conversely, laboratories performing the quantitative approach were able to determine the expected JAK2^V617F AB. Quantitative results were reliable across all mutation loads with moderate variability at low AB (0.1 and 1%; CV = 0.46 and 0.77, respectively). Remarkably, all laboratories clearly distinguished between the 0.1 and 1% mutated samples.

In conclusion, a qualitative approach is not sensitive enough to detect the JAK2^V617F mutation, especially at low AB. On the contrary, the ipsogen JAK2 MutaQuant CE-IVD kit resulted in a high, efficient and sensitive quantification detection of all mutation loads. This study sets the basis for the standardization of molecular techniques for JAK2^V617F determination, which will require the employment of approved operating procedures and the use of certificated standards, such as the recent WHO 1st International Reference Panel for Genomic JAK2^V617F.

The hOCT1 and ABCB1 polymorphisms do not influence the pharmacodynamics of nilotinib in chronic myeloid leukemia

First-line nilotinib in chronic myeloid leukemia is more effective than imatinib to achieve early and deep molecular responses, despite poor tolerability or failure observed in one-third of patients. The toxicity and efficacy of tyrosine kinase inhibitors might depend on the activity of transmembrane transporters. However, the impact of transporters genes polymorphisms in nilotinib setting is still debated. We investigated the possible correlation between single nucleotide polymorphisms of hOCT1 (rs683369 [c.480C>G]) and ABCB1 (rs1128503 [c.1236C>T], rs2032582 [c.2677G>T/A], rs1045642 [c.3435C>T]) and nilotinib efficacy and toxicity in a cohort of 78 patients affected by chronic myeloid leukemia in the context of current clinical practice. The early molecular response was achieved by 81% of patients while 64% of them attained deep molecular response (median time, 26 months). The 36-month event-free survival was 86%, whereas 58% of patients experienced toxicities. Interestingly, hOCT1 and ABCB1 polymorphisms alone or in combination did not influence event-free survival or the adverse events rate. Therefore, in contrast to data obtained in patients treated with imatinib, hOCT1 and ABCB1 polymorphisms do not impact on nilotinib efficacy or toxicity. This could be relevant in the choice of the first-line therapy: patients with polymorphisms that negatively condition imatinib efficacy might thus receive nilotinib as first-line therapy.

Spontaneous recurrent hematuria and hematospermia: Unique manifestations of von Willebrand disease type I. Case report

In this report we describe the case of a patient with unrecognized von Willebrand disease (vWD), in whom the only presenting symptoms were spontaneous and recurrent hematuria with bladder tamponade, associated with recurrent hematospermia. The diagnosis was made only after several admissions to the hospital. We suggest to include coagulopathies such as vWD as part of the evaluation in patients with unexplained genito-urinary bleeding.

Dasatinib first-line: Multicentric Italian experience outside clinical trials

Dasatinib was approved for the treatment of chronic phase (CP) chronic myeloid leukemia (CML) patients in first line therapy based on the demonstration of efficacy and safety reported in patients enrolled in clinical trials. We describe a multicentric Italian "real-life" experience of dasatinib used as frontline treatment outside clinical trials. One hundred and nine patients (median age 54 years) were treated from January 2012 to December 2013. Increased incidence of high risk patients were detected according to stratification (26% according to Sokal score, 19% according to Euro score and 16% according to EUTOS) when compared to company sponsored studies. Median time from diagnosis to start of dasatinib was 18 days. Ten patients received unscheduled starting dose (6 patients 50mg and 4 patients 80 mg QD), whereas 99 patients started with 100mg QD. At 3 months, 92% of patients achieved a BCR-ABL ratio less than 10%. At 6 months, the rate of CCyR was 91% and the rate of MR3 was 40%, with 8% of the patients reaching MR4.5. Ninety-three patients were evaluable at 12 months: the rate of MR3 was 62%, with MR4.5 being achieved by 19% of the patients. At a median follow-up of 12 months, 27 patients (24.7%) were receiving the drug at reduced dose. Two patients (1.8%) experienced a lymphoid blast crisis and the overall incidence of resistance was 8%. As regards safety, the major side effects recorded were thrombocytopenia, neutropenia and pleural effusions, which occurred in 22%, 10% and 8% of patients, respectively. Present results, achieved in a large cohort of patients treated outside clinical trials, further confirm the efficacy and safety of dasatinib as firstline treatment in CML.

Thrombosis in essential thrombocytemia and early/prefibrotic primary myelofibrosis: the role of the WHO histological diagnosis

Background

Vascular events represent the most frequent complications of thrombocytemias. We aimed to evaluate their risk in the WHO histologic categories of Essential Thrombocytemia (ET) and early Primary Myelofibrosis (PMF).

Methods

From our clinical database of 283 thrombocytemic patients, we selected those with available bone marrow histology performed before any treatment, at or within 1 year from diagnosis, and reclassified the 131 cases as true ET or early PMF, with or without fibrosis, according to the WHO histological criteria. Vaso-occlusive events at diagnosis and in the follow-up were compared in the WHO-groups.

Results

Histologic review reclassified 61 cases as ET and 72 cases as early PMF (26 prefibrotic and 42 with grade 1 or 2 fibrosis). Compared to ET, early PMF showed a significant higher rate of thrombosis both in the past history (22% vs 8%) and at diagnosis (15.2% vs 1.6%), and an increased leukocyte count (8389 vs 7500/mmc). Venous thromboses (mainly atypical) were relatively more common in PMF than in ET. Patients with prefibrotic PMF, although younger, showed a significant higher 15-year risk of developing thrombosis (48% vs 16% in fibrotic PMF and 17% in ET). At multivariate analysis, age and WHO histology were both independent risk-factors for thrombosis during follow-up; patients >60 yr-old or with prefibrotic PMF showed a significantly higher risk at 20 years than patients <60 yr-old with ET or fibrotic PMF (47% vs 4%, p = 0.005).

Conclusions

Our study support the importance of WHO histologic categories in the thrombotic risk stratification of patients with thrombocytemias.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2020211863144412.

Cardiovascular events and intensity of treatment in polycythemia vera

BACKGROUND

Current treatment recommendations for patients with polycythemia vera call for maintaining a hematocrit of less than 45%, but this therapeutic strategy has not been tested in a randomized clinical trial.

METHODS

We randomly assigned 365 adults with JAK2-positive polycythemia vera who were being treated with phlebotomy, hydroxyurea, or both to receive either more intensive treatment (target hematocrit, <45%) (low-hematocrit group) or less intensive treatment (target hematocrit, 45 to 50%) (high-hematocrit group). The primary composite end point was the time until death from cardiovascular causes or major thrombotic events. The secondary end points were cardiovascular events, cardiovascular hospitalizations, incidence of cancer, progression to myelofibrosis, myelodysplasia or leukemic transformation, and hemorrhage. An intention-to-treat analysis was performed.

RESULTS

After a median follow-up of 31 months, the primary end point was recorded in 5 of 182 patients in the low-hematocrit group (2.7%) and 18 of 183 patients in the high-hematocrit group (9.8%) (hazard ratio in the high-hematocrit group, 3.91; 95% confidence interval [CI], 1.45 to 10.53; P=0.007). The primary end point plus superficial-vein thrombosis occurred in 4.4% of patients in the low-hematocrit group, as compared with 10.9% in the high-hematocrit group (hazard ratio, 2.69; 95% CI, 1.19 to 6.12; P=0.02). Progression to myelofibrosis, myelodysplasia or leukemic transformation, and bleeding were observed in 6, 2, and 2 patients, respectively, in the low-hematocrit group, as compared with 2, 1, and 5 patients, respectively, in the high-hematocrit group. There was no significant between-group difference in the rate of adverse events.

CONCLUSIONS

In patients with polycythemia vera, those with a hematocrit target of less than 45% had a significantly lower rate of cardiovascular death and major thrombosis than did those with a hematocrit target of 45 to 50%. (Funded by the Italian Medicines Agency and others; ClinicalTrials.gov number, NCT01645124, and EudraCT number, 2007-006694-91.).

Comparison of two regimens for the treatment of elderly patients with acute lymphoblastic leukaemia (ALL)

Acute lymphoblastic leukemia (ALL) represents a rare malignancy in the elderly and few authors have specifically focused on the treatment of ALL in this setting. We recently published the results of a prospective phase II study comprising an induction therapy with vincristine, Daunoxome and dexamethasone (VDXD) given to 15 patients aged 60 years. Here, we update the results after enrolling 17 patients, and we compare these with the results obtained in 17 elderly patients treated according to the GIMEMA ALL 0288 protocol. With the VDXD combination, elderly ALL had a higher CR rate (76.5%) than with the 0288 protocol (41%), and it was likely due to both lower induction mortality (17.5% vs. 35%) and a less resistant disease (6% vs. 24%). Infectious complications were more frequent with the VDXD combination whereas non-hematological side effects were comparable. Despite the similar DFS obtained with the two induction treatments, median EFS (3.9 months with 0288 vs. 12.8 with VDXD; p = 0.0486) and OS (4.5 vs. 21 months; p = 0.0239) were significantly higher with the VDXD regimen. In elderly ALL patients the administration of high-dose daunorubicin as a liposomal compound is feasible and seems able to improve CR rate, EFS and OS without increase in toxicity.

Pegylated liposomal doxorubicin in the treatment of primary cutaneous T-cell lymphomas

Pegylated liposomal doxorubicin (Peg-Doxo) is a promising drug for advanced/recalcitrant primary cutaneous T-cell lymphomas (CTCLs). This prospective phase II trial enrolled 19 patients. We observed overall and complete response rates of 84.2% and 42.1% (with no significant differences between stage I-IIA and IIB-IV patients), and 11% grade III/IV toxicity. After a maximum 46 month-follow-up, median overall (OS), event-free (EFS) and progression-free (PFS) survival were 34, 18 and 19 months. OS, EFS and PFS rates at 46 months were 44%, 30% and 37% respectively. Peg-Doxo seems to be an active and safe principle that should be used in plurirelapsed, early stage-MF and in combination with other chemotherapeutic agents in advanced and aggressive CTCLs.

Thalidomide, dexamethasone, and pegylated liposomal doxorubicin (ThaDD) for patients older than 65 years with newly diagnosed multiple myeloma

We present the results of a phase 2 study using thalidomide, dexamethasone, and pegylated liposomal doxorubicin (ThaDD) in the treatment of 50 patients older than 65 years with newly diagnosed multiple myeloma. Thalidomide 100 mg was administered orally at bedtime continuously, dexamethasone 40 mg was administered orally on days 1 to 4 and 9 to 12, and pegylated liposomal doxorubicin 40 mg/m2 was administered intravenously on day 1 over the 28-day cycle. Response was assessed according to the EBMT criteria. Seventeen (34%) patients achieved CR, 7 (14%) nCR, 5 (10%) VGPR, 15 (30%) PR, and 5 (10%) MR, resulting in an ORR of 98%. Only 1 patient (2%) presented progressive disease. Time to progression (TTP), event-free survival (EFS), and overall survival (OS) projected at 3 years were 60%, 57%, and 74%, respectively, and these parameters were significantly higher in those patients achieving a response of at least VGPR versus those who did not. Grade 3 and 4 nonhematologic adverse events were constipation (10%), fatigue (6%), tremors (4%), mucositis (4%), and palmar-plantar erythrodysesthesia (2%). Grade 3 and 4 neutropenia occurred in 12% of patients. Grade 3 and 4 infections and thromboembolic accidents were observed in 22% and 14% of patients, respectively. In the treatment of elderly patients with newly diagnosed multiple myeloma, ThaDD is a very effective regimen with manageable toxicity.

Low-dose thalidomide with pegylated liposomal doxorubicin and high-dose dexamethasone for relapsed/refractory multiple myeloma: a prospective, multicenter, phase II study

The aim of this prospective, multicenter, phase II study was to investigate the combination of pegylated liposomal doxorubicin (Caelyx) 40 mg/m2 on day 1 every 28 days, dexamethasone 40 mg p.o. on days 1-4 and 9-12 and thalidomide 100 mg daily in 50 patients with advanced multiple myeloma. Twenty-six percent of patients achieved a complete response, 6% a near complete response, 6% a very good partial response, 38% a partial response, 16% a minor response and 8% progressed, for an overall response rate of 92%. The median event-free survival was 17 months and the median overall survival was not reached. Grade 3 non-hematologic toxicity occurred in 12% of patients, thromboembolic disease in 12% and severe infection in 16%. The combination of pegylated liposomal doxorubicin, dexamethasone an thalidomide is safe and very effective in advanced multiple myeloma.

Long-term experience with low-dose interferon-alpha and PUVA in the management of early mycosis fungoides

OBJECTIVES

Combined high-dose Interferon-alpha and psoralen plus ultraviolet A irradiation (PUVA) have been reported to be effective in the treatment of early mycosis fungoides (MF); however, our study is the first controlled prospective study in the literature exploring the activity and tolerability of the combination with low dosages and evaluating further clinical outcome of early-MF patients.

METHODS

We carried out a multicentric prospective Phase II clinical study on 89 patients with early-stage IA to IIA MF treated for 14 months with low-dose IFN-alpha2b (6-18 MU/wk) and PUVA. Treatment success was analysed in terms of freedom from treatment failure.

RESULTS AND CONCLUSIONS

Complete remission (CR) was achieved in 84% and an overall response rate in 98% of cases: six-month CR was associated with a non-confluent skin infiltrate at histology (P = 0.044) and 14-month CR with high epidermal CD1a+ dendritic-cell density (P = 0.030). The combination protocol was successfully tolerated and the most common reason of 'failure' was related to relapse and not to toxicity. Sustained remissions were achieved in 20% of patients. High CD8+ lymphoid T-cell density was associated with a lower relapse rate (P = 0.002). We think that our combination therapy can be considered an alternative approach compared with other modalities. Good immunological host surveillance in the skin lesions seems to be an optimal basis for the therapeutic success.

Expression of c-myb and B-myb oncogenes on myelofibrotic marrow fibroblasts

The term IMF (Idiopathic Myelofibrosis) refers to a primary bone marrow disease in which the normal haematopoietic bone marrow cells are for unknown reasons replaced by connective tissue. The pathogenesis of the disease has not been clarified yet. We have speculated that the increment of proliferation of bone marrow fibroblasts in IMF may be the consequence of the over-expression of some oncogenes, leading or contributing to the fibrosis via a cell amplification. Thus, we investigated the possible role of the c-myb and B-myb genes in IMF and control bone marrow fibroblasts in different culture conditions to evaluate proliferation parameters in the absence or presence of serum. Using the reverse transcriptase polymerase chain reaction technique, we demonstrated that the kinetics of induction was similar for both c-myb and B-myb during the proliferation of normal bone marrow fibroblasts. When compared to normal controls, cultured IMF fibroblasts showed more elevated values of c-myb and B-myb RNA; furthermore, after a 72 hours stimulation with serum, c-myb and B-myb messages remained relatively high in myelofibrotic fibroblasts. Finally, after serum starvation, c-myb and to a lesser extent B-myb RNA levels remained unusually high in IMF fibroblasts, while under the same experimental conditions c-myb and B-myb messages became virtually undetectable in normal bone marrow fibroblasts. To our knowledge this work represents the first description of an abnormal behavior of these genes in IMF fibroblasts.

[Biologic aspects and clinical use of granulocyte growth factor]

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]

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.