Patients with chronic lymphocytic leukemia (CLL) have an impaired antibody response to coronavirus disease 2019 (COVID-19) vaccination. Here, we evaluated the antibody response to a third BNT162b2 mRNA vaccine in patients with CLL/small lymphocytic lymphoma (SLL) who failed to achieve a humoral response after standard 2-dose vaccination regimen. Anti–severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies were measured 3 weeks after administration of the third dose. In 172 patients with CLL, the antibody response rate was 23.8%. Response rate among actively treated patients (12.0%; n = 12/100) was lower compared with treatment-naïve patients (40.0%; n = 16/40; OR = 4.9, 95% CI 1.9-12.9; P < .001) and patients off-therapy (40.6%; n = 13/32; OR = 5.0, 95% CI 1.8-14.1; P < .001), (P < .001). In patients actively treated with Bruton’s tyrosine kinase (BTK) inhibitors or venetoclax ± anti-CD20 antibody, response rates were extremely low (15.3%, n = 9/59, and 7.7%, n = 3/39, respectively). Only 1 of the 28 patients (3.6%) treated with anti-CD20 antibodies <12 months prior to vaccination responded. In a multivariate analysis, the independent variables that were associated with response included lack of active therapy (OR = 5.6, 95% CI 2.3-13.8; P < .001) and serum immunoglobulin A levels ≥80 mg/dL (OR = 5.8, 95% CI 2.1-15.9; P < .001). In patients with CLL/SLL who failed to achieve a humoral response after standard 2-dose BNT162b2 mRNA vaccination regimen, close to a quarter responded to the third dose of vaccine. The antibody response rates were lower during active treatment and in patients with a recent exposure (<12 months prior to vaccination) to anti-CD20 therapy. This trial was registered at www.clinicaltrials.gov as #NCT04862806.

Patients with chronic lymphocytic leukemia (CLL) have a suboptimal humoral response to vaccination. Recently, BNT162b2, an mRNA COVID-19 vaccine with a high efficacy of 95% in immunocompetent individuals, was introduced. We investigated the safety and efficacy of the BNT162b2 mRNA COVID-19 vaccine in patients with CLL from nine medical centers in Israel, Overall 400 patients were included, of whom 373 were found to be eligible for the analysis of antibody response. The vaccine appeared to be safe and only grade 1-2 adverse events were seen in 50% of the patients. Following the second dose, an antibody response was detected in 43% of the cohort. Among these CLL patients, 61% of the treatment-na ve patients responded to the vaccine, while responses developed in only 18% of those with ongoing disease, 37% of those previously treated with a BTK inhibitor and 5% of those recently given an anti-CD20 antibody. Among patients treated with BCL2 as monotherapy or in combination with anti-CD20, 62% and 14%, respectively, developed an immune response. There was a high concordance between neutralizing antibodies and positive serological response to spike protein. Based on our findings we developed a simple seven-factor score including timing of any treatment with anti-CD20, age, treatment status, and IgG, IgA, IgM and hemoglobin levels. The sum of all the above parameters can serve as a possible estimate to predict whether a given CLL patient will develop sufficient antibodies. In conclusion, the BNT162b2 mRNA COVID-19 vaccine was found to be safe in patients with CLL, but its efficacy is limited, particularly in treated patients.

In this study we assessed the prognostic significance of absolute monocyte count and selected the best cut-off value at diagnosis in a large cohort of patients with diffuse large B-cell lymphoma. Data were retrieved for therapy-naïve patients with diffuse large B-cell lymphoma followed in Israel and Italy during 1993–2010. A final cohort of 1017 patients was analyzed with a median follow up of 48 months and a 5-year overall survival rate of 68%. The best absolute monocyte count cut-off level was 630/mm³ and the 5-year overall survival for patients with counts below this cut-off was 71%, whereas it was 59% for those with a count >630 mm³ (P=0.0002). Of the 1017 patients, 521 (51%) were treated with chemo-immunotherapy, and in this cohort, using multivariate analysis, elevated monocyte count retained a negative prognostic value even when adjusted for International Prognostic Index (HR1.54, P=0.009). This large study shows that a simple parameter such as absolute monocyte count (>630/mm³) can easily be used routinely in the evaluation of newly diagnosed diffuse large B-cell lymphoma to identify high-risk patients with a worse survival in the rituximab era.

Patients with chronic lymphocytic leukemia (CLL) may be more susceptible to Coronavirus disease 2019 (COVID-19) due to age, disease, and treatment-related immunosuppression. We aimed to assess risk factors of outcome and elucidate the impact of CLL-directed treatments on the course of COVID-19. We conducted a retrospective, international study, collectively including 941 patients with CLL and confirmed COVID-19. Data from the beginning of the pandemic until March 16, 2021, were collected from 91 centers. The risk factors of case fatality rate (CFR), disease severity, and overall survival (OS) were investigated. OS analysis was restricted to patients with severe COVID-19 (definition: hospitalization with need of oxygen or admission into an intensive care unit). CFR in patients with severe COVID-19 was 38.4%. OS was inferior for patients in all treatment categories compared to untreated (p < 0.001). Untreated patients had a lower risk of death (HR = 0.54, 95% CI:0.41–0.72). The risk of death was higher for older patients and those suffering from cardiac failure (HR = 1.03, 95% CI:1.02–1.04; HR = 1.79, 95% CI:1.04–3.07, respectively). Age, CLL-directed treatment, and cardiac failure were significant risk factors of OS. Untreated patients had a better chance of survival than those on treatment or recently treated.

Merkel cell carcinoma (MCC) is a rare and aggressive skin tumor. The link between tumorigenesis and immunosuppression is well known and the increased prevalence of MCC in human immunodeficiency virus carriers and organ transplant recipients and in patients with hemato-oncological neoplasias is now well recognized over the past decade. In this respect, chronic lymphocytic leukemia (CLL) seems to be the most frequent neoplasia associated with the development of MCC. Very recently, a newly described virus, the Merkel cell polyomavirus, was found in ∼80% of MCC tumor samples and is in fact the first member of the polyomavirus family to be associated with human tumors. The virus appears to play a role in the pathogenesis of MCC and may constitute the missing link between immunosuppression and the development of MCC. This review summarizes the current knowledge relating to MCC and its pathogenesis, stressing the link with hematologic neoplasias in general and to CLL in particular. We describe the permissive immunologic environment, which enables the virus-containing tumor cells to survive and proliferate in disorders like CLL. More studies are still needed to confirm this appealing theory in a more convincing manner.