A low total metabolic tumor volume independently predicts for a longer time to first treatment in initially observed, low tumor burden follicular lymphoma

Watchful waiting is an acceptable management strategy for advanced-stage, low tumor burden (LTB) patients with follicular lymphoma (FL). However, the prediction of how long this treatment-free observation period will last remains imperfect. We explored whether total metabolic tumor volume (TMTV) and other positron emission tomography parameters were predictive of time to first treatment (TTFT). We analyzed 97 grade 1-3A advanced-stage LTB FL patients and found that a high TMTV was associated with other tumor burden features at diagnosis. Patients with a TMTV above our established cutoff of 50 mL had a significantly shorter median duration of observation (2.6 vs. 8.8 years; p = 0.001). At 5 years, 77% of patients with a high TMTV and 46% of patients with a low TMTV required treatment. In the multivariable analysis, a high TMTV was the only independent factor predicting TTFT (hazard ratio = 2.09; p = 0.017). Overall, TMTV is a strong predictor of the duration of observation in LTB FL patients. Upon validation of our cutoff in external series and standardization of the methodology, the TMTV could become an additional factor to consider deferring or initiating treatment in otherwise LTB patients.

Thrombotic and bleeding complications in patients with chronic lymphocytic leukemia and severe COVID-19: a study of ERIC, the European Research Initiative on CLL

Background

Patients with chronic lymphocytic leukemia (CLL) may be more susceptible to COVID-19 related poor outcomes, including thrombosis and death, due to the advanced age, the presence of comorbidities, and the disease and treatment-related immune deficiency. The aim of this study was to assess the risk of thrombosis and bleeding in patients with CLL affected by severe COVID-19.

Methods

This is a retrospective multicenter study conducted by ERIC, the European Research Initiative on CLL, including patients from 79 centers across 22 countries. Data collection was conducted between April and May 2021. The COVID-19 diagnosis was confirmed by the real-time polymerase chain reaction (RT-PCR) assay for SARS-CoV-2 on nasal or pharyngeal swabs. Severe cases of COVID-19 were defined by hospitalization and the need of oxygen or admission into ICU. Development and type of thrombotic events, presence and severity of bleeding complications were reported during treatment for COVID-19. Bleeding events were classified using ISTH definition. STROBE recommendations were used in order to enhance reporting.

Results

A total of 793 patients from 79 centers were included in the study with 593 being hospitalized (74.8%). Among these, 511 were defined as having severe COVID: 162 were admitted to the ICU while 349 received oxygen supplementation outside the ICU. Most patients (90.5%) were receiving thromboprophylaxis. During COVID-19 treatment, 11.1% developed a thromboembolic event, while 5.0% experienced bleeding. Thrombosis developed in 21.6% of patients who were not receiving thromboprophylaxis, in contrast to 10.6% of patients who were on thromboprophylaxis. Bleeding episodes were more frequent in patients receiving intermediate/therapeutic versus prophylactic doses of low-molecular-weight heparin (LWMH) (8.1% vs. 3.8%, respectively) and in elderly. In multivariate analysis, peak D-dimer level and C-reactive protein to albumin ratio were poor prognostic factors for thrombosis occurrence (OR = 1.022, 95%CI 1.007‒1.038 and OR = 1.025, 95%CI 1.001‒1.051, respectively), while thromboprophylaxis use was protective (OR = 0.199, 95%CI 0.061‒0.645). Age and LMWH intermediate/therapeutic dose administration were prognostic factors in multivariate model for bleeding (OR = 1.062, 95%CI 1.017–1.109 and OR = 2.438, 95%CI 1.023–5.813, respectively).

Conclusions

Patients with CLL affected by severe COVID-19 are at a high risk of thrombosis if thromboprophylaxis is not used, but also at increased risk of bleeding under the LMWH intermediate/therapeutic dose administration.

Results of ARI-0001 CART19 cell therapy in patients with relapsed/refractory CD19-positive acute lymphoblastic leukemia with isolated extramedullary disease

We evaluated outcomes of 18 patients with isolated extramedullary disease (iEMD) relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL) treated with the CD19-directed CAR T cells ARI-0001 in two centers (adult and pediatric), including patients treated in the CART19-BE-01 trial and the consecutive compassionate use program. iEMD was detected by PET-CT in 78% (14/18), and/or by cerebrospinal fluid analysis in 28% (5/18). Patients received cyclophosphamide and fludarabine followed by 1 × 10⁶ ARI-0001 cells/kg, initially as a single dose (first patient) and later split into three fractions (10%, 30%, and 60%). Cytokine release syndrome (CRS) occurred in 50% (9/18) of patients, with no cases of grade ≥3 CRS, and 1 case (6%) of grade 1 neurotoxicity. Tocilizumab was used in 6% of patients (1/18). Procedure-related mortality was 0% at 2 years. Objective responses were seen in 94% (95% confidence interval [CI]: 73%-99%) of patients, with complete responses (CR) seen in 78% (95% CI: 52%-94%) of them. Progression-free and overall survival were 49% (95% CI: 30%-79%) and 61% (95% CI: 40%-92%) at 2 years. In conclusion, the use of ARI-0001 cells in patients with R/R ALL and iEMD was associated with a safety and efficacy profile that is comparable with what is observed in patients with marrow involvement and in line with other CART19 products.

Serum soluble CD23 levels are an independent predictor of time to first treatment in chronic lymphocytic leukemia

Serum soluble CD23 (sCD23) levels have been acknowledged as a prognostic factor in patients with chronic lymphocytic leukemia (CLL), but their potential relevance has not been analyzed in recent times. We retrospectively studied 338 CLL, small lymphocytic lymphoma, or CLL-type monoclonal B-cell lymphocytosis patients from a single institution, with available sCD23 levels at diagnosis. Baseline features and outcomes were compared between patients with sCD23 ≤/>1000 UI/L. The 140 patients (41%) who had sCD23 > 1000 UI/L showed adverse-risk clinical and biological characteristics. High sCD23 levels were predictive of a shorter time to first treatment (5-year probability of requiring treatment: 60 vs. 20%, p < 0.0001; hazard ratio (HR) = 1.72, p = 0.003 in a multivariable model also including the CLL International Prognostic Index and the absolute lymphocyte count), and a poorer 5-year overall survival (70 vs. 82%, p = 0.0009). These data suggest the potential of sCD23 to predict treatment-free survival and to shed light on mechanisms of activity and resistance to CD23-directed therapies.

First external validation of the FLIPI-L score in a single-center series of patients with follicular lymphoma

The FLIPI-L has recently been proposed as a novel prognostic index in follicular lymphoma (FL), combining FLIPI and the presence of lymphopenia. In our single-center validation in 381 FL patients, lymphopenia was less frequent than in the original publication and thus the distribution of risk categories was different. Although it was not able to properly predict time to first treatment, FLIPI-L performed slightly better than FLIPI alone in the prediction of response, early relapse, progression-free and overall survival, and histological transformation. This new tool or others encompassing parameters from the microenvironment might improve upon the prognostic ability of classical scores.

Prognostic ability of five clinical risk scores in follicular lymphoma: A single-center evaluation

With the intention of identifying follicular lymphoma (FL) patients at higher risk of progression, early relapse (POD24), histological transformation (HT) or death, multiple risk scores (RS) have been proposed. However, it has not yet been established whether any of them globally outperforms the others. We evaluated the clinical utility and statistical performance of the five most widely used clinical scores (IPI, ILI, FLIPI, FLIPI2, PRIMA-PI) in a single-center series of 414 grade 1-3A FL patients diagnosed in the rituximab era. Overall concordance (proportion of patients allocated to the same risk category by all five RS) was 24%. FLIPI and FLIPI2 were predictive of time to first treatment. All five scores were predictive of response, POD24, progression-free, and OS, while only FLIPI predicted HT. IPI identified a small subset (7%) of truly high-risk patients (10-year OS of 16%). In subgroup analyses, we showed that ILI is useful in the prognostication of limited-disease patients, and PRIMA-PI is an age-independent score that can identify a high-risk subset of older patients. Performance metrics were slightly better for IPI in terms of calibration (Harrell's c-index 0.73), without major differences among RS regarding other parameters. Although the incorporation of molecular and imaging data will continue to refine the stratification of FL patients, FLIPI remains the most powerful clinical prognostic index in the rituximab era, predicting the greatest number of endpoints.

Age and comorbidity are determining factors in the overall and relative survival of patients with follicular lymphoma

Frailty and concurrent medical conditions are crucial factors in the management of follicular lymphoma (FL). We evaluated the impact of age and comorbidity on survival, causes of death, histological transformation (HT), and second malignancies (SM) in a large single-center series of grade 1-3A FL. We studied 414 patients diagnosed in the rituximab era, categorized into three age groups (≤60, 61-70, >70 years) and two comorbidity groups (Charlson Comorbidity Index, CCI, 0-1 and ≥2). Despite a similar cumulative incidence of relapse, older and comorbid patients had a lower 10-year overall survival (OS, 88, 65, and 41% for patients ≤60 years, 61-70 years, and >70 years, P<0.0001; and 76 vs. 51% for CCI 0-1 and ≥2, P<0.0001). In a multivariate analysis for OS, comorbidity retained its prognostic impact (HR=2.5, P=0.0003). The proportion of patients dying due to FL was higher among those ≤60 years (74%) and those with a CCI 0-1 (67%). Furthermore, 10-year excess mortality (survival reduction) was more prominent for patients >70 years (30%) and those with a CCI ≥2 (32%). Patients with a CCI ≥2 also had a higher incidence of SM. These data encourage a comprehensive pre-treatment evaluation and a tailored therapeutic approach for all FL patients.

A low lymphocyte-to-monocyte ratio is an independent predictor of poorer survival and higher risk of histological transformation in follicular lymphoma

The lymphocyte-to-monocyte ratio (LMR) is a prognostic factor in different neoplasms, but its potential importance in follicular lymphoma (FL) is not well defined. We studied 384 FL patients for which the LMR was available at diagnosis. Baseline features and outcomes were compared between patients with an LMR ≤/>2.5. The 76 patients (20%) who had an LMR ≤2.5 were older and had a higher tumor burden. A low LMR was predictive of a lower 10-y progression-free survival (32 vs. 55%, p = .001) and overall survival (35 vs. 78%, p < .0001; HR = 2.3, p = .003 in a 6-element multivariable model). A low LMR was also an independent risk factor for histological transformation (11 vs. 6% at 10 years, p = .01). Likewise, patients with a low LMR had a higher rate of second malignancies. The potential utility of this widely available parameter and its contribution to well-established prognostic scores need to be explored in independent, prospective series.

Catecholamines enhance dihydrolipoamide dehydrogenase inactivation by the copper Fenton system. Enzyme protection by copper chelators

Catecholamines (CAs: epinephrine, norepinephrine, dopamine, L-DOPA, 6-hydroxydopamine) and o-diphenols (DOPAC and catechol) enhanced dihydrolipoamide dehydrogenase (LADH) inactivation by Cu(II)/H2O2 (Cu-Fenton system). The inhibition of LADH activity correlated with Cu(II), H2O2 and CA concentrations. Similar inhibitions were obtained with the assayed CAs and o-diphenols. CAs enhanced HO. radical production by Cu(II)/H2O2, as demonstrated by benzoate hydroxylation and deoxyribose oxidation; LADH counteracted the pro-oxidant effect of CAs by scavenging hydroxyl radicals. Captopril, dihydrolipoamide, dihydrolipoic acid, DL-dithiothreitol, GSSG, trypanothione and histidine effectively preserved LADH from oxidative damage, whereas N-acetylcysteine, N-(2-mercaptopropionylglycine) and lipoamide were less effective protectors. Catalase (though neither bovine serum albumin nor superoxide dismutase) protected LADH against the Cu(II)/H2O2/CAs systems. Denatured catalase protected less than the native enzyme, its action possibly depending on Cu-binding. LADH increased and Captopril inhibited epinephrine oxidation by Cu(II)/H2O2 and Cu(II). The summarized evidence supports the following steps for LADH inactivation: (1) reduction of LADH linked-Cu(II) to Cu(I) by CAs; (2) production of HO. from H2O2 by LADH-linked Cu(I) (Haber-Weiss reaction) and (3) oxidation of aminoacid residues at the enzyme active site by site-specifically generated HO. radicals. Hydrogen peroxide formation from CAs autoxidation may contribute to LADH inactivation.