Incidence of blast phase in myelofibrosis patients according to anemia severity at ruxolitinib start and during therapy.

BACKGROUND: Anemia is frequently present in patients with myelofibrosis (MF), and it may be exacerbated by treatment with the JAK2-inhibitor ruxolitinib (RUX). Recently, a relevant blast phase (BP) incidence has been reported in anemic MF patients unexposed to RUX. METHODS: The authors investigated the incidence of BP in 886 RUX-treated MF patients, included in the "RUX-MF" retrospective study. RESULTS: The BP incidence rate ratio (IRR) was 3.74 per 100 patient-years (3.74 %p-y). At therapy start, Common Terminology Criteria for Adverse Events grade 3-4 anemia (hemoglobin [Hb] <8 g/dL) and severe sex/severity-adjusted anemia (Hb <8/<9 g/dL in women/men) were present in 22.5% and 25% patients, respectively. IRR of BP was 2.34 in patients with no baseline anemia and reached respectively 4.22, 4.89, and 4.93 %p-y in patients with grade 1, 2, and 3-4 anemia. Considering the sex/severity-adjusted Hb thresholds, IRR of BP was 2.85, 4.97, and 4.89 %p-y in patients with mild/no anemia, moderate, and severe anemia. Transfusion-dependent patients had the highest IRR (5.03 %p-y). Progression-free survival at 5 years was 70%, 52%, 43%, and 27% in patients with no, grade 1, 2, and 3-4 anemia, respectively (p < .001). At 6 months, 260 of 289 patients with no baseline anemia were receiving ruxolitinib, and 9.2% had developed a grade 3-4 anemia. By 6-month landmark analysis, BP-free survival was significantly worse in patients acquiring grade 3-4 anemia (69.3% vs. 88.1% at 5 years, p < .001). CONCLUSIONS: This study highlights that anemia correlates with an increased risk of evolution into BP, both when present at baseline and when acquired during RUX monotherapy. Innovative anemia therapies and disease-modifying agents are warranted in these patients.

Ruxolitinib in cytopenic myelofibrosis: Response, toxicity, drug discontinuation, and outcome.

BACKGROUND: Patients with cytopenic myelofibrosis (MF) have more limited therapeutic options and poorer prognoses compared with patients with the myeloproliferative phenotype. AIMS AND METHODS: Prognostic correlates of cytopenic phenotype were explored in 886 ruxolitinib-treated patients with primary/secondary MF (PMF/SMF) included in the RUX-MF retrospective study. Cytopenia was defined as: leukocyte count <4 × 109 /L and/or hemoglobin <11/<10 g/dL (males/females) and/or platelets <100 × 109 /L. RESULTS: Overall, 407 (45.9%) patients had a cytopenic MF, including 249 (52.4%) with PMF. In multivariable analysis, high molecular risk mutations (p = .04), intermediate 2/high Dynamic International Prognostic Score System (p < .001) and intermediate 2/high Myelofibrosis Secondary to Polycythemia Vera and Essential Thrombocythemia Prognostic Model (p < .001) remained associated with cytopenic MF in the overall cohort, PMF, and SMF, respectively. Patients with cytopenia received lower average ruxolitinib at the starting (25.2 mg/day vs. 30.2 mg/day, p < .001) and overall doses (23.6 mg/day vs. 26.8 mg/day, p < .001) and achieved lower rates of spleen (26.5% vs. 34.1%, p = .04) and symptom (59.8% vs. 68.8%, p = .008) responses at 6 months compared with patients with the proliferative phenotype. Patients with cytopenia also had higher rates of thrombocytopenia at 3 months (31.1% vs. 18.8%, p < .001) but lower rates of anemia (65.6% vs. 57.7%, p = .02 at 3 months and 56.6% vs. 23.9% at 6 months, p < .001). After competing risk analysis, the cumulative incidence of ruxolitinib discontinuation at 5 years was 57% and 38% in patients with cytopenia and the proliferative phenotype (p < .001), whereas cumulative incidence of leukemic transformation was similar (p = .06). In Cox regression analysis adjusted for Dynamic International Prognostic Score System score, survival was significantly shorter in patients with cytopenia (p < .001). CONCLUSIONS: Cytopenic MF has a lower probability of therapeutic success with ruxolitinib as monotherapy and worse outcome. These patients should be considered for alternative therapeutic strategies.

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.

Peripheral blasts are associated with responses to ruxolitinib and outcomes in patients with chronic-phase myelofibrosis.

BACKGROUND: The presence of peripheral blasts (PB) is a negative prognostic factor in patients with primary and secondary myelofibrosis (MF) and PB ≥4% was associated with a particularly unfavorable prognosis. Ruxolitinib (RUX) is the JAK1/2 inhibitor most used for treatment of MF-related splenomegaly and symptoms. Its role has not been assessed in correlation with PB. METHODS: In 794 chronic-phase MF patients treated with RUX, we evaluated the impact of baseline percentage of PB on response (spleen and symptoms responses) and outcome (RUX discontinuation-free, leukemia-free, and overall survival). Three subgroups were compared: PB-0 (no PB, 61.3%), PB-4 (PB 1%-4%, 33.5%), and PB-9 (PB 5%-9%, 5.2%). RESULTS: At 3 and 6 months, spleen responses were less frequently achieved by PB-4 (P = .001) and PB-9 (P = .004) compared to PB-0 patients. RUX discontinuation-free, leukemia-free, and overall survival were also worse for PB-4 and PB-9 patients (P = .001, P = .002, and P < .001, respectively). CONCLUSIONS: Personalized approaches beyond RUX monotherapy may be useful in PB-4 and particularly in PB-9 patients.

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.

The complex karyotype landscape in chronic lymphocytic leukemia allows the refinement of the risk of Richter syndrome transformation.

Complex karyotype (CK) at chronic lymphocytic leukemia (CLL) diagnosis is a negative biomarker of adverse outcome. Since the impact of CK and its subtypes, namely type-2 CK (CK with major structural abnormalities) or high-CK (CK with ≥5 chromosome abnormalities), on the risk of developing Richter syndrome (RS) is unknown, we carried out a multicenter real-life retrospective study to test its prognostic impact. Among 540 CLL patients, 107 harbored a CK at CLL diagnosis, 78 were classified as CK2 and 52 as high-CK. Twenty-eight patients developed RS during a median follow-up of 6.7 years. At the time of CLL diagnosis, CK2 and high-CK were more common and predicted the highest risk of RS transformation, together with advanced Binet stage, unmutated (U)-IGHV, 11q-, and TP53 abnormalities. We integrated these variables into a hierarchical model: high-CK and/or CK2 patients showed a 10-year time to RS (TTRS) of 31%; U-IGHV/11q- /TP53 abnormalities/Binet stage B-C patients had a 10-year TTRS of 12%; mutated (M)-IGHV without CK and TP53 disruption a 10-year TTRS of 3% (P<0.0001). We herein demonstrate that CK landscape at CLL diagnosis allows the risk of RS transformation to be refined and we recapitulated clinico-biological variables into a prognostic model.

Treatment-free remission in chronic myeloid leukemia patients treated front-line with nilotinib: 10-year followup of the GIMEMA CML 0307 study.

We report the final analysis, with a 10-year follow-up, of the phase II study GIMEMA CML 0307 (NCT00481052), which enrolled 73 adult patients (median age 51 years; range, 18-83) with newly diagnosed chronic-phase chronic myeloid leukemia to investigate the efficacy and the toxicity of front-line treatment with nilotinib. The initial dose was 400 mg twice daily; the dose was reduced to 300 mg twice daily as soon as this dose was approved and registered. The 10-year overall survival and progression- free survival were 94.5%. At the last contact, 36 (49.3%) patients were continuing nilotinib (22 patients at 300 mg twice daily, 14 at lower doses), 18 (24.7%) patients were in treatment-free remission, 14 (19.2%) were receiving other tyrosinekinase inhibitors and four (5.5%) patients have died. The rates of major and deep molecular responses by 10 years were 96% and 83%, respectively. The median times to major and deep molecular response were 6 and 18 months, respectively. After a median duration of nilotinib treatment of 88 months, 24 (32.9%) patients discontinued nilotinib while in stable deep molecular response. In these patients, the 2-year estimated treatment-free survival was 72.6%. The overall treatment-free remission rate, calculated on all enrolled patients, was 24.7% (18/73 patients). Seventeen patients (23.3%), at a median age of 69 years, had at least one arterial obstructive event. In conclusion, the use of nilotinib front-line in chronic phase chronic myeloid leukemia can induce a stable treatment-free remission in a relevant number of patients, although cardiovascular toxicity remains of concern.

Ruxolitinib rechallenge in resistant or intolerant patients with myelofibrosis: Frequency, therapeutic effects, and impact on outcome.

BACKGROUND: After ruxolitinib discontinuation, the outcome of patients with myelofibrosis (MF) is poor with scarce therapeutic possibilities. METHODS: The authors performed a subanalysis of an observational, retrospective study (RUX-MF) that included 703 MF patients treated with ruxolitinib to investigate 1) the frequency and reasons for ruxolitinib rechallenge, 2) its therapeutic effects, and 3) its impact on overall survival. RESULTS: A total of 219 patients (31.2%) discontinued ruxolitinib for ≥14 days and survived for ≥30 days. In 60 patients (27.4%), ruxolitinib was rechallenged for ≥14 days (RUX-again patients), whereas 159 patients (72.6%) discontinued it permanently (RUX-stop patients). The baseline characteristics of the 2 cohorts were comparable, but discontinuation due to a lack/loss of spleen response was lower in RUX-again patients (P = .004). In comparison with the disease status at the first ruxolitinib stop, at its restart, there was a significant increase in patients with large splenomegaly (P < .001) and a high Total Symptom Score (TSS; P < .001). During the rechallenge, 44.6% and 48.3% of the patients had spleen and symptom improvements, respectively, with a significant increase in the number of patients with a TSS reduction (P = .01). Although the use of a ruxolitinib dose > 10 mg twice daily predicted better spleen (P = .05) and symptom improvements (P = .02), the reasons for/duration of ruxolitinib discontinuation and the use of other therapies before rechallenge were not associated with rechallenge efficacy. At 1 and 2 years, 33.3% and 48.3% of RUX-again patients, respectively, had permanently discontinued ruxolitinib. The median overall survival was 27.9 months, and it was significantly longer for RUX-again patients (P = .004). CONCLUSIONS: Ruxolitinib rechallenge was mainly used in intolerant patients; there were clinical improvements and a possible survival advantage in many cases, but there was a substantial rate of permanent discontinuation. Ruxolitinib rechallenge should be balanced against newer therapeutic possibilities.

In chronic lymphocytic leukaemia, SLAMF1 deregulation is associated with genomic complexity and independently predicts a worse outcome.

In a series of 349 patients with chronic lymphocytic leukaemia (CLL), we found lower levels of signalling lymphocytic activation molecule family member 1 (SLAMF1) expression in cases with highly complex karyotypes, as defined by the presence of five or more chromosomal abnormalities (CK5; P < 0·001) and with major chromosomal structural abnormalities (P < 0·001). SLAMF1 downregulation was significantly associated with advanced Binet Stage (P = 0·001), CD38 positivity (P < 0·001), high ß2 -microglobulin levels (P < 0·001), immunoglobulin heavy chain variable region gene (IGHV) unmutated status (P < 0·001), 11q deletion (P < 0·001), tumour protein p53 (TP53) disruption (P = 0·011) and higher risk CLL International Prognostic Index categories (P < 0·001). Multivariate analysis showed that downregulated SLAMF1 levels had independent negative prognostic impact on time-to-first treatment (P < 0·001) and overall survival (P < 0·001).

Second primary malignancy in myelofibrosis patients treated with ruxolitinib.

Ruxolitinib (RUX), the first JAK1/JAK2 inhibitor approved for myelofibrosis (MF) therapy, has recently been associated with the occurrence of second primary malignancies (SPMs), mainly lymphomas and non-melanoma skin cancers (NMSCs). We analyzed the incidence, risk factors and outcome of SPMs in 700 MF patients treated with RUX in a real-world context. Median follow-up from starting RUX was 2·9 years. Overall, 80 (11·4%) patients developed 87 SPMs after RUX start. NMSCs were the most common SPMs (50·6% of the cases). Multivariate analysis demonstrated that male sex [hazard ratio (HR): 2·37, 95% confidence interval (95%CI): 1·22-4·60, P = 0·01] and thrombocytosis> 400 × 109 /l at RUX start (HR:1·98, 95%CI: 1·10-4·60, P = 0·02) were associated with increased risk for SPMs. Risk factors for NMSC alone were male sex (HR: 3·14, 95%CI: 1·24-7·92, P = 0·02) and duration of hydroxycarbamide and RUX therapy > 5 years (HR: 3·20, 95%CI: 1·17-8·75, P = 0·02 and HR: 2·93, 95%CI: 1·39-6·17, P = 0·005 respectively). In SPMs excluding NMSCs, male sex (HR: 2·41, 95%CI: 1·11-5·25, P = 0·03), platelet > 400 × 109 /l (HR: 3·30, 95%CI: 1·67-6·50, P = 0·001) and previous arterial thromboses (HR: 3·47, 95%CI: 1·48-8·14, P = 0·004) were shown to be associated with higher risk of SPMs. While it is reassuring that no aggressive lymphoma was documented, active skin surveillance is recommended in all patients and particularly after prolonged hydroxycaramide therapy; oncological screening should be triggered by thrombocytosis and arterial thrombosis, particularly in males.

Impact of comorbidities and body mass index on the outcome of polycythemia vera patients.

In 816 patients with 2016 World Health Organization-defined polycythemia vera (PV) enrolled in a multicenter retrospective study, we investigated the predictive value of Charlson comorbidity index (CCI) and body mass index (BMI) on thrombosis, progression to post-PV myelofibrosis (PPV-MF) and survival. Patients were subgrouped according to CCI = 0 (58.1%, no comorbidities) or CCI ≥ 1 (41.9%) and according to normal/underweight (BMI < 25, 54.5%) or overweight/obesity (BMI ≥ 25, 45.5%) at PV diagnosis. BMI was available for 529 patients. Patients with CCI ≥ 1 were older and more frequently presented cardiovascular risk factors compared to patients with CCI = 0 (p < 0.001), while overweight/obese patients were more frequently males (p < 0.001). Cumulative incidence of thromboses with death as competing risk was 13.3% at 10 years. Multivariable analysis with death as competing risk showed that previous thromboses (subdistribution hazard ratio [SHR]: 2.1, p = 0.01) and hypertension (SHR: 1.77, p = 0.04) were significantly associated with a higher thrombotic risk, while BMI ≥ 25 lost statistical significance (SHR: 1.69, p = 0.05) and CCI ≥ 1 was excluded after evaluation of goodness of fit. After a median follow-up of 6.1 years, progression to PPV-MF occurred in 44 patients, and 75 patients died. BMI ≥ 25 was associated with a lower probability of progression to PPV-MF (SHR: 0.38, CI95%: 0.15-0.94, p = 0.04) and better survival (hazard ratio [HR]: 0.42, CI95%: 0.18-0.97, p = 0.04). CCI ≥ 1 did not affect progression to PPV-MF (p = 0.44) or survival (p = 0.71).  The evaluation of CCI and BMI may improve the prognostic definition of PV. In patients with hypertension an accurate evaluation of thrombotic risk is warranted.

Efficacy of idelalisib and rituximab in relapsed/refractory chronic lymphocytic leukemia treated outside of clinical trials. A report of the Gimema Working Group.

Because the efficacy of new drugs reported in trials may not translate into similar results when used in the real-life, we analyzed the efficacy of idelalisib and rituximab (IR) in 149 patients with relapsed/refractory chronic lymphocytic leukemia treated at 34 GIMEMA centers. Median progression-free survival (PFS) and overall survival were 22.9 and 44.5 months, respectively; performance status (PS) ≥2 and ≥3 previous lines of therapy were associated with shorter PFS and overall survival (OS). 48% of patients were on treatment at 12 months; the experience of the centers (≥5 treated patients) and PS 0-1 were associated with a significantly longer treatment duration (p = 0.015 and p = 0.002, respectively). TP53 disruption had no prognostic significance. The overall response rate to subsequent treatment was 49.2%, with median OS of 15.5 months and not reached in patients who discontinued, respectively, for progression and for toxicity (p < 0.01). Treatment breaks ≥14 days were recorded in 96% of patients and adverse events mirrored those reported in trials. In conclusion, this real-life analysis showed that IR treatment duration was longer at experienced centers, that the ECOG PS and ≥3 lines of previous therapy are strong prognostic factor and that the overall outcome with this regimen was superimposable to that reported in a randomized trial.

Life after ruxolitinib: Reasons for discontinuation, impact of disease phase, and outcomes in 218 patients with myelofibrosis.

BACKGROUND: After discontinuing ruxolitinib, the outcome of patients with myelofibrosis reportedly has been poor. The authors investigated whether disease characteristics before the receipt of ruxolitinib may predict drug discontinuation in patients with myelofibrosis and whether reasons for drug discontinuation, disease phase at discontinuation, and salvage therapies may influence the outcome. METHODS: A centralized electronic clinical database was created in 20 European hematology centers, including clinical and laboratory data for 524 patients who received ruxolitinib for myelofibrosis. RESULTS: At 3 years, 40.8% of patients had stopped ruxolitinib. Baseline predictors of drug discontinuation were: intermediate-2-risk/high-risk category (Dynamic International Prognostic Score System), a platelet count <100 ×109 per liter, transfusion dependency, and unfavorable karyotype. At last contact, 268 patients (51.1%) had discontinued therapy, and the median drug exposure was 17.5 months. Fifty patients (18.7%) died while taking ruxolitinib. The reasons for discontinuation in the remaining 218 patients were the lack (22.9%) or loss (11.9%) of a spleen response, ruxolitinib-related adverse events (27.5%), progression to blast phase (23.4%), ruxolitinib-unrelated adverse events (9.2%), and allogeneic transplantation during response (5.1%). The median survival after ruxolitinib was 13.2 months and was significantly better in the 167 patients who discontinued ruxolitinib in chronic phase (27.5 vs 3.9 months for those who discontinued in blast phase; P < .001). No survival differences were observed among patients who discontinued ruxolitinib in chronic phase because of lack of response, loss of response, or ruxolitinib-related adverse events. The use of investigational agents and/or ruxolitinib rechallenge were associated with improved outcome. CONCLUSIONS: The survival of patients with myelofibrosis after discontinuation of ruxolitinib is poor, particularly for those who discontinue in blast phase. Salvage therapies can improve outcome, emphasizing the need for novel therapies.

Risk factors for progression to blast phase and outcome in 589 patients with myelofibrosis treated with ruxolitinib: Real-world data.

The impact of ruxolitinib therapy on evolution to blast phase (BP) in patients with myelofibrosis (MF) is still uncertain. In 589 MF patients treated with ruxolitinib, we investigated incidence and risk factors for BP and we described outcome according to disease characteristics and treatment strategy. After a median follow-up from ruxolitinib start of 3 years (range 0.1-7.6), 65 (11%) patients transformed to BP during (93.8%) or after treatment. BP incidence rate was 3.7 per 100 patient-years, comparably in primary and secondary MF (PMF/SMF) but significantly lower in intermediate-1 risk patients (2.3 vs 5.6 per 100 patient-years in intermediate-2/high-risk patients, P < .001). In PMF and SMF cohorts, previous interferon therapy seemed to correlate with a lower probability of BP (HR 0.13, P = .001 and HR 0.22, P = .02, respectively). In SMF, also platelet count <150 × 109 /l (HR 2.4, P = .03) and peripheral blasts ≥3% (HR 3.3, P = .004) were significantly associated with higher risk of BP. High-risk category according to dynamic International Prognostic Score System (DIPSS) and myelofibrosis secondary to PV and ET Collaboration Prognostic Model (MYSEC-PM predicted BP in patients with PMF and SMF, respectively. Median survival after BP was 0.2 (95% CI: 0.1-0.3) years. Therapy for BP included hypomethylating agents (12.3%), induction chemotherapy (9.2%), allogeneic transplant (6.2%) or supportive care (72.3%). Patients treated with supportive therapy had a median survival of 6 weeks, while 73% of the few transplanted patients were alive at a median follow-up of 2 years. Progression to BP occurs in a significant fraction of ruxolitinib-treated patients and is associated with DIPSS and MYSEC-PM risk in PMF and SMF, respectively.

The combination of complex karyotype subtypes and IGHV mutational status identifies new prognostic and predictive groups in chronic lymphocytic leukaemia.

BACKGROUND: Complex karyotype (CK) is a heterogeneous category with a negative impact in chronic lymphocytic leukaemia (CLL). Our group has recently reported that CK patients with major structural abnormalities (i.e. CK2) are characterised by a worse prognosis, as compared to other lesions within CK(CK1). METHODS: We performed a multicentre retrospective study to test whether the combination of CK subtypes with IGHV status could be a relevant prognostic and predictive tool. RESULTS: Among 522 patients 13% harboured CK2, 41% CK1 and/or U-IGHV (U-CK1) and 46% M-IGHV without any CK subtypes (M-noCK). After a median follow-up of 5.8 years, CK2 patients had the shortest TTFT (5-year TTFT 31%, 39 and 81%, p < 0.0001) and OS (5-year OS 67%, 85 and 93%, p < 0.0001) as compared to U-CK1 or M-noCK cases, regardless of TP53 abnormalities. CK2 patients also had the worst outcome after chemoimmunotherapy. In fact, the median TTNT after FCR or BR was 1.86 and 4.79 years for CK2 and U-CK1, but not reached for M-noCK patients (p < 0.0005). CONCLUSIONS: We herein suggest that the combined assessment of the IGHV mutational status and CK subtypes refines the prognostication of CLL, allowing to identify M-IGHV patients without any CK subtypes who are characterised by an indolent disease and excellent outcome after chemoimmunotherapy.

Observational study of chronic myeloid leukemia Italian patients who discontinued tyrosine kinase inhibitors in clinical practice.

It is judged safe to discontinue treatment with tyrosine kinase inhibitors (TKI) for chronic myeloid leukemia (CML) in experimental trials on treatment-free remission (TFR). We collected a total of 293 Italian patients with chronic phase CML who discontinued TKI in deep molecular response. Seventy-two percent of patients were on treatment with imatinib, and 28% with second generation TKI at the time of discontinuation. Median duration of treatment with the last TKI was 77 months [Interquartile Range (IQR) 54;111], median duration of deep molecular response was 46 months (IQR 31;74). Duration of treatment with TKI and duration of deep molecular response were shorter with second generation TKI than with imatinib (P<0.001). Eighty-eight percent of patients discontinued as per clinical practice, and reasons for stopping treatment were: toxicity (20%), pregnancy (6%), and shared decision between treating physician and patient (62%). After a median follow up of 34 months (range, 12-161) overall estimated TFR was 62% (95%CI: 56;68). At 12 months, TFR was 68% (95%CI: 62;74) for imatinib, 73% (95%CI: 64;83) for second generation TKI. Overall median time to restart treatment was six months (IQR 4;11). No progressions occurred. Although our study has the limitation of a retrospective study, our experience within the Italian population confirms that discontinuation of imatinib and second generation TKI is feasible and safe in clinical practice.

Impact of 2016 WHO diagnosis of early and overt primary myelofibrosis on presentation and outcome of 232 patients treated with ruxolitinib.

The 2016 WHO criteria identified early primary myelofibrosis (PMF) as an individual entity with milder clinical features and better outcome compared with overt PMF. Here, we compared early and overt PMF patients treated with ruxolitinib in terms of baseline clinical/laboratory characteristics, response, and toxicity to treatment. We observed that early-PMF patients achieve better and more stable spleen and symptoms responses, with significantly lower rates of hematological toxicities. No differences in overall and leukemia-free survival were detected between the two cohorts. The application of 2016 WHO criteria is crucial to identify those PMF patients who deserve a stricter monitoring during treatment.

Impact of comorbidities and body mass index in patients with myelofibrosis treated with ruxolitinib.

Comorbidities defined by the Charlson comorbidity index (CCI) and body mass index (BMI) are significantly associated with outcome in patients who receive continuous treatment with tyrosine kinase inhibitors. We evaluated the impact of CCI and BMI on responses, drug-related toxicities, and outcome in a cohort of 402 patients with myelofibrosis (MF) treated with ruxolitinib in 23 European Hematology Centers. Comorbidities were evaluable in all 402 patients. A higher (≥ 3) CCI did not correlate with a lower spleen reduction at any time (p = 0.68) or symptoms' response (p = 0.11), but influenced the onset of anemia during the first 3 months of treatment and later (p = 0.02 and p = 0.03, respectively) in patients without anemia baseline. BMI was evaluable in 380 patients and did not correlate with differences in spleen and symptoms response (p = 0.57 and p = 0.49, respectively). A higher CCI and a lower BMI correlated also with a reduced overall survival (p < 0.001 and p = 0.02, respectively). The achievement of a spleen response at 6 months could counterbalance the negative impact of comorbidities, while patients who were underweight when starting ruxolitinib and did not achieve a spleen response at 6 months were projected to the worse outcome. In MF patients treated with ruxolitinib, BMI and comorbidities did not influence the achievement of spleen/symptom responses, but they contributed to the early identification of patients who deserve a strict monitoring during treatment.

Outcome of very elderly chronic myeloid leukaemia patients treated with imatinib frontline.

Very elderly (> 75 years) chronic myeloid leukaemia (CML) patients at diagnosis are sometimes treated with different doses of imatinib (IM) based on concomitant diseases and physicians' judgement. However, data on long-term follow-up of these patients are still lacking. To investigate treatment response and outcome, we retrospectively revised an Italian database of 263 very elderly CML patients receiving IM from the time of diagnosis. Median age at diagnosis was 78.5 years and 56% of patients had 2 or 3 comorbidities. A complete haematological and cytogenetic response were achieved in 244 (92.8%) and 184 (69.9%) patients, respectively. In 148 cases (56.2%), a major molecular response was observed, which was deep in 63 cases (24%). A blastic phase occurred in 11 patients (4.2%). After a median follow-up of 45.0 months, 93 patients have died (9 from disease progression) and 104 (39.5%) are still in treatment with IM. Incidence of grades 3-4 haematological and non-haematological toxicity was similar to those reported in younger patients. Five-year event-free survival was 54.5% and 45.2% in patients ≤ 80 years and > 80 years, respectively (p = 0.098). Five years OS was 75.7% and 61.6% in patients ≤80 years and > 80 years, respectively (p = 0.003). These findings show that IM plays an important role in frontline treatment of very elderly CML patients without increased toxicity and any effort to treat these patients with standard doses should be made in order to achieve responses as in younger subjects.

In chronic lymphocytic leukaemia with complex karyotype, major structural abnormalities identify a subset of patients with inferior outcome and distinct biological characteristics.

Complex karyotype (CK) is a negative prognostic factor in chronic lymphocytic leukaemia (CLL). However, CK is a heterogeneous cytogenetic category. Unbalanced rearrangements were present in 73·3% of 90 CLL patients with CK (i.e. ≥3 chromosome aberrations in the same clone), and were associated with a shorter overall survival (P = 0·025) and a shorter time to first treatment (P = 0·043) by multivariate analysis. Patients with unbalanced rearrangements presented a distinct mRNA expression profile. In conclusion, CLL patients with unbalanced rearrangements might represent a subset of very high-risk CLL patients with distinct clinical and biological characteristics.