Silvia Calatroni

World Health Organization classification in combination with cytogenetic markers improves the prognostic stratification of patients with de novo primary myelodysplastic syndromes

This study correlated chromosomal defects with French–American–British (FAB)/World Health Organization (WHO) classification subtypes, proposed a revised International Prognostic Scoring System (IPSS) cytogenetic grouping; and established which classification, when used with the IPSS cytogenetic categories, best predicted clinical outcome in the myelodysplastic syndromes (MDS). A higher prevalence of chromosomal defects and distinct defects were observed in patients with multi‐lineage dysplasia and a blast cell percentage >10%. Abnormalities of the long arm of chromosome 3, del(7)(q31q35), trisomy 8, del(11)(q14q23), del(12p) and 20q‐ could be segregated from their respective IPSS cytogenetic categories and used to develop new cytogenetic subgroups. Clinical parameters, FAB/WHO classification, IPSS score and standard or revised cytogenetic categories were statistically relevant for overall survival (OS) and progression‐free intervals (PFI) and were included within five distinct multivariate models compared by the Akaike Information Criterion. To predict OS, the best models included age, WHO classification and standard or revised IPSS cytogenetic categories; to predict PFI, the best model included the same variables and revised cytogenetic categories. In conclusion, (i) the WHO classification was associated with a more homogeneous cytogenetic pattern than the FAB classification, (ii) WHO classification and standard/revised IPSS cytogenetic categories were much more effective than IPSS for predicting MDS clinical outcome, (iii) revised cytogenetic subgroups predicted PFI more effectively than standard categories.

Is FISH a relevant prognostic tool in myelodysplastic syndromes with a normal chromosome pattern on conventional cytogenetics? A study on 57 patients.

Conventional cytogenetics (CC) at clinical diagnosis shows a normal karyotype in 40–60% of de novo myelodysplastic syndromes (MDSs). Fluorescence in situ hybridization (FISH) might detect occult aberrations in these patients. Therefore, we have used FISH to check 57 MDS patients who were karyo-typically normal on CC. At clinical diagnosis, FISH revealed a clonal abnormality in 18–28% interphase cells from nine patients, five of whom also presented the same defect on metaphase FISH. In five out of nine patients, the occult defect effected a change in the international prognostic scoring system (IPSS). An abnormal FISH pattern was significantly correlated with marrow blast cell percentage (P<10−3) and IPSS (P<10−3). Patients with an occult abnormality showed an overall survival and event-free survival significantly inferior in comparison to those of patients with normal FISH (P<10−3, P<10−3). Death and AML progression were 15- and eight-fold more frequent in FISH abnormal patients. In conclusion, occult defects (1) are revealed in about 15% of CC normal MDS patients, (2) are overlooked by CC either because of the poor quality of metaphases or their submicroscopic nature, (3) are clinically relevant as they may cause a change in the IPSS category and may identify a fraction of CC normal patients with an unfavorable clinical outcome.

Incidence and prognostic significance of karyotype abnormalities in de novo primary myelodysplastic syndromes: a study on 331 patients from a single institution

The impact of clinical parameters, International Prognostic Scoring System (IPSS) scores/cytogenetic categories, and some single cytogenetic defects on overall survival (OS) and time to myelodysplastic syndromes (MDS)/AML progression (progression-free interval (PFI)) was evaluated in 331 MDS patients. Statistical analysis demonstrated that OS and PFI were significantly affected by all these parameters. Since single 7q- showed a better survival than the poor IPSS cytogenetic category (P=0.009), it was considered as a new prognostic entity (‘modified IPSS categories’). In multivariate analysis OS was significantly influenced by age, marrow blast cell percentage, number of cytopenias and either modified or standard IPSS cytogenetic categories; hazard ratios for MDS/AML progression were influenced by all the former, except for age and cytopenias. Multivariate analysis of del(7)(q31q35) confirmed the results of univariate analysis, but the Akaike Information Criterion showed no difference in evaluating OS and PFI between the modified and standard IPSS cytogenetic grouping. In conclusion, (i) chromosome defects as grouped by IPSS and blast cell percentage are the most relevant parameters for predicting OS and PFI; (ii) the prognostic power of the IPSS cytogenetic grouping is not ameliorated by the introduction of del(7)(q31q35) as a new entity; (iii) complex karyotypes have a prognostic value independent of blast cell percentage.

A sequence of immuno‐chemotherapy with Rituximab, mobilization of in vivo purged stem cells, high‐dose chemotherapy and autotransplant is an effective and non‐toxic treatment for advanced follicular and mantle cell lymphoma

Summary. Options for relapsed/refractory indolent lymphoma include chemotherapy, immunotherapy and high‐dose therapy with autologous support. The best combination of these approaches, however, is not defined. We treated 10 patients with relapsed/refractory follicular (n = 7) or mantle cell lymphoma (n = 3) using chemotherapy, immunotherapy, high‐dose therapy and autotransplant in a sequence of four phases, each designed to play a specific role in tumour eradication. After the debulking with VACOP‐B (doxorubicin, cyclophosphamide, etoposide, vincristine, prednisone, bleomycin) (phase 1), 9/10 patients responded but none achieved a molecular response. After the immuno‐chemotherapy phase, which combined Rituximab with vincristine and cyclophosphamide, seven patients were in complete response (CR) and three in good partial response (PR), and all those with a molecular marker of disease showed a disappearance of the signal from marrow and blood. Phase 3, which coupled high‐dose cytarabine with Rituximab, was effective in mobilizing an adequate number of progenitor cells that were polymerase chain reaction negative in all informative cases. Phase 4 consisted of high‐dose therapy with autologous support followed by two doses of Rituximab. Autograft was performed in nine patients. The haematopoietic recovery was as expected. This sequence of chemotherapy, immuno‐chemotherapy, stem cell mobilization with in vivo purging and autotransplant, organized in four blocks of treatment, was simple to administer and devoid of toxic effects. It permits rapid attainment of clinical and molecular response and enables the harvest of lymphoma‐free peripheral blood progenitor cells even in heavily pretreated patients with relapsed or refractory disease.

Immunochemotherapy with in vivo purging and autotransplant induces long clinical and molecular remission in advanced relapsed and refractory follicular lymphoma

BACKGROUND To evaluate the clinical outcome of patients with relapsed or refractory follicular lymphoma treated with immunochemotherapy, in vivo purging and high-dose therapy with autotransplant. PATIENTS AND METHODS Sixty-four patients were enrolled in the trial. Primary end point was progression-free survival (PFS). Secondary end points were the in vivo purging effect on stem-cell harvest and the impact of molecular response on the outcome. RESULTS At enrollment, 59% of patients were PCR+ for bcl-2 rearrangement in bone marrow (PCR-informative). After the immunochemotherapy, before mobilization, 97% obtained complete response or partial response and 87% of patients informative for bcl-2 were molecularly negative. Sixty-one patients proceeded to in vivo purging and peripheral blood stem cell (PBSC) mobilization with rituximab and high-dose AraC. The median number of CD34+ cells collected was 16.6 x 10(6)/kg. Of 33 PCR-informative patients, the harvests resulted in PCR- in all. Fifty-eight patients received high-dose therapy and autotransplant of in vivo purged PBSC. After a median follow-up of 3.5 years, 41 patients are in complete remission. Five-year PFS is 59%. CONCLUSION This study demonstrates that patients with advanced relapsed or refractory follicular lymphoma treated with immunochemotherapy, in vivo purging and autotransplant may obtain long-lasting PFS. In bcl-2-positive patients, in vivo purging allows the harvest of lymphoma-free PBSC. Absence of the bcl-2 rearrangement after autotransplant is associated with persistent clinical remission.

Clinical relevance of cytogenetics in myelodysplastic syndromes

Abstract:  Myelodysplastic syndromes (MDS) are a group of heterogeneous stem cell disorders with different clinical behaviors and outcomes. Conventional cytogenetics (CC) studies have demonstrated that the majority of MDS patients harbor clonal chromosome defects. The probability of discovering a chromosomal abnormality has been increased by fluorescence in situ hybridization (FISH), which has revealed that about 15% of patients with a normal chromosome pattern on CC may instead present cryptic defects. Cytogenetic abnormalities, except for the interstitial long‐arm deletion of chromosome 5 (5q−), are not specific for any French‐American‐British (FAB)/World Health Organization (WHO) MDS subtypes, demonstrate the clonality of the disease, and identify peculiar morphological entities, thus confirming clinical diagnosis. In addition, chromosome abnormalities are independent prognostic factors predicting overall survival and the likelihood of progression in acute myeloid leukemia.

Acute myeloid leukemia (AML) having evolved from essential thrombocythemia (ET): distinctive chromosome abnormalities in patients treated with pipobroman or hydroxyurea

ET is a chronic myeloproliferative disorder rarely evolving into AML, sometimes preceded by a myelodysplastic syndrome (MDS). Such transformations mostly occur in patients treated with radiophosphorous (32P) or alkylating agents, especially busulfan. Recently, concern has also arisen about the long-term safety of hydroxyurea (HU). Pipobroman (PI), a well tolerated and simple to use drug, constitutes a valid alternative to those cytoreductive treatments. The present study reports on 155 ET patients treated at our institution from 1985 to 1995, and monitored until December 2000. A good control of thrombocytosis was achieved with PI as the only treatment in 106 patients and with HU in 23 patients. Twenty-six patients received no treatment. After a median follow-up of 104 months, seven patients (four treated with HU, and three with PI) developed AML whereas one patient treated with PI developed MDS. A significant difference in progression-free survival was observed between HU- and PI-treated patients (P = 0.004). A short-arm deletion of chromosome 17 was most frequently detected in HU-treated patients, while a long-arm trisomy of chromosome 1 and a monosomy 7q were seen in PI-treated patients. No TP53 mutation was discovered in the six patients studied (two HU-treated and four PI-treated). We conclude that these cytogenetic abnormalities are not linked to the natural history of the disease, but rather that they might be induced by the cytoreductive treatment.

A model of in vivo purging with Rituximab and high-dose AraC in follicular and mantle cell lymphoma

Summary:We studied a model of in vivo purging with Rituximab and high-dose (HD) cytarabine in 14 patients with relapsed/refractory follicular lymphoma and two with refractory mantle cell lymphoma enrolled in a program of HD chemotherapy and autotransplant. After two courses of debulking immunochemotherapy with Rituximab, Vincristine and Cyclophosphamide, we used a combination of Rituximab, HD cytarabine and granulocyte colony-stimulating factor for peripheral blood stem cells (PBSC) mobilization. The median number of CD34+ cells collected was 14.69 × 106/kg (range 5.74–73.2). Monitoring of peripheral CD19+ and CD20+ B cells prior to and throughout the purging period showed that a treatment with Rituximab, Vincristine and Cyclophosphamide results in a profound depletion of B cells in peripheral blood. B-cell depletion persists during mobilization with Rituximab and HD cytarabine allowing a collection of PBSC free of B cells (median CD19+ and CD20+ cells counts 0%). Of nine patients PCR positive for bcl-2 or bcl-1 in blood and marrow at the start of immunochemotherapy, all showed PCR-negative PBSC. In conclusion, in patients with indolent lymphoma, the concurrent administration of Rituximab and HD cytarabine is a safe and efficient method to obtain in vivo purged PBSC. Immunochemotherapy prior to mobilization produces B-cell depletion and seems to be a useful preparative step.

Nilotinib restores long-term full-donor chimerism in Ph-positive acute lymphoblastic leukemia relapsed after allogeneic transplantation

Nilotinib restores long-term full-donor chimerism in Ph-positive acute lymphoblastic leukemia relapsed after allogeneic transplantation

Molecular Genetics of Acute Myeloid Leukemia

Abstract: Recurring chromosomal abnormalities are detected in most patients with acute myeloid leukemia (AML). They may be associated with a distinct AML FAB subtype or may identify distinct clinicobiological entities within the same FAB subtype. Therefore, cytogenetic investigation has a pivotal role in AML diagnosis. In addition, it is one of the most valuable prognostic determinants of the disease, as recently demonstrated. The development of new molecular techniques, such as reverse transcriptase polymerase chain reaction and fluorescence in situ hybridization, has allowed perfect definition of the chromosome regions containing genes with a crucial role in normal hemopoiesis and leukemia. Understanding the action of such genes provides new insights into AML pathogenesis and has led us to envisage new therapeutic options.