Second primary malignancies in chronic lymphocytic leukaemia: Skin, solid organ, haematological and Richter's syndrome

Update on the management of relapsed/refractory chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) predominantly affects older adults, characterized by a relapsing and remitting pattern with sequential treatments available for many patients. Identification of progressive/relapsed CLL should prompt close monitoring and early discussion about the next therapies when treatment indications are present. The intervening period represents an opportunity to optimize patient health, including establishing adequate vaccination and surveillance for second primary malignancies, and treating non-CLL-related comorbidities which may impact well-being and CLL therapy. We now see patients with relapsed/refractory (RR) CLL in the clinic who have been previously treated with chemoimmunotherapy (CIT) and/or one or more novel therapies. Continuous covalent inhibitors of Bruton's tyrosine kinase (cBTKi) and fixed-duration venetoclax (Ven)-anti-CD20 monoclonal antibody (mAb) are preferred over CIT given the survival advantages associated with these therapies, although have never been evaluated head-to-head. While both classes are effective for RR CLL, potential side effects and the logistics of administration differ. Few randomized data demonstrate the sequential use of cBTKi and fixed-duration Ven-anti-CD20 mAb; however, they may be used in either sequence. Newer non-covalent BTKi, active against BTK C481 resistance mutations emerging with continuous cBTKi exposure, and novel approaches such as BTK degraders, bispecific antibodies, and chimeric antigen receptor T-cell therapies demonstrate impressive efficacy. In this review of RR CLL we explore relevant investigations, consideration of broader CLL- and non-CLL-related health needs, and evidence for efficacy and safety of B-cell receptor inhibitors and Ven, including available data to support drug sequencing or switching. We describe novel approaches to RR CLL, including rechallenging with fixed-duration therapies, allogeneic stem cell transplant indications in the novel therapy era, and highlight early data supporting the use of T-cell directing therapies and novel drug targets.

Assessment of second primary malignancies among treated and untreated patients with chronic lymphocytic leukemia using real-world data from the USA

Aim: Improved management of chronic lymphocytic leukemia (CLL) has resulted in a growing population of CLL survivors; these patients have a higher risk of developing second primary malignancies (SPMs) versus the general population. This retrospective cohort study aims to assess the timing, frequency, incidence and types of SPMs in treated and untreated patients with CLL in the USA, using the Surveillance, Epidemiology, and End Results (SEER) Medicare database, which links a nationally representative cancer registry with Medicare claims data. Patients & methods: Patients aged ≥66 years with newly diagnosed CLL between 1 January 2010 and 31 December 2016, who were enrolled in Parts A and B of Medicare for ≥12 months pre-diagnosis of CLL were selected from the database. Patients were assessed for ≥36 months until the end of continuous enrollment in Medicare Parts A, B and D, a switch to a health maintenance organization, death, or end of the study period (December 2019). Results: Of 3053 patients included in the analyses, 620 (20.3%) were treated and 2433 (79.7%) were untreated within 36 months of diagnosis. Overall, 638 (20.9%) patients developed a SPM, 26.8% of patients in the treated cohort and 19.4% of patients in the untreated cohort. The most common SPMs for both cohorts were squamous cell carcinoma and acute myeloid leukemia. Among the 166 treated patients who developed a SPM, a greater proportion developed their first SPM after treatment initiation versus those who developed their first SPM prior to treatment initiation (p < 0.001). A significantly lower percentage of patients who received targeted therapy developed a SPM (p < 0.05) versus patients treated with anti-CD20 + chemotherapy. Conclusion: Findings indicate that treatment type and timing can affect SPM development in patients with CLL. Combined with previous findings, this can help inform best practices in monitoring for SPM in patients with CLL.

A population level analysis of second hematological malignancies in chronic lymphocytic leukemia/small lymphocytic lymphoma survivors in the era of targeted therapies

With improvement in survival after chronic lymphocytic leukemia (CLL) diagnosis, the real-world burden of second hematological malignancies (SHM) has not been comprehensively assessed in recent era. We analyzed risk, incidence, and outcomes of SHM in CLL patients between 2000 and 2019 using SEER database. CLL patients had greater risk for hematological malignancies than general population [SIR, standardized incidence ratio (95% CI):2.58 (2.46-2.70); p < 0.05]. The risk for subsequent lymphoma increased by 1.75 folds in 2015-2019 compared to 2000-2004. The duration, after CLL diagnosis, of maximum risk for SHM decreased as 60-119 months for time-period 2000-2004, 6-11 months for 2005-2009 to 2-5 months for 2010-2014 and 2015-2019. Incidence of SHM was 2.5% in CLL survivors (1736/70,346) with lymphoid SHM being more common than myeloid SHM, and DLBCL being the most common pathology (n = 610, 35% of all SHM). Male sex, age ≤65 years at CLL diagnosis, and chemotherapy treatment were associated with higher risk for SHM. The median gap between CLL and SHM diagnoses was 46 months. The median survival for de-novo-AML, t-MN, CML, and aggressive NHL was 63, 86, 95, and 96 months respectively. Although SHM remains rare, there is increased risk in recent era, likely due to improved survival in CLL patients, necessitating active surveillance strategies.

Chronic lymphocytic leukaemia Australasian consensus practice statement

Chronic lymphocytic leukaemia (CLL) is the most common haematological malignancy in Australia and New Zealand (ANZ). Considerable changes to diagnostic and management algorithms have occurred within the last decade. The availability of next-generation sequencing and measurable residual disease assessment by flow cytometry allow for advanced prognostication and response assessments. Novel therapies, including inhibitors of Bruton's tyrosine kinase (BTKi) and B-cell lymphoma 2 (BCL2) inhibitors, have transformed the treatment landscape for both treatment-naïve and relapsed/refractory disease, particularly for patients with high-risk genetic aberrations. Recommendations regarding appropriate supportive management continue to evolve, and special considerations are required for patients with CLL with respect to the global SARS-CoV-2 pandemic. The unique funding and treatment environments in Australasia highlight the need for specific local guidance with respect to the investigation and management of CLL. This consensus practice statement was developed by a broadly representative group of ANZ experts in CLL with endorsement by peak haematology bodies, with a view to providing this standardised guidance.

Immunological Aspects of Richter Syndrome: From Immune Dysfunction to Immunotherapy

Richter Syndrome (RS) is defined as the development of an aggressive lymphoma in patients with a previous or simultaneous diagnosis of chronic lymphocytic leukemia (CLL). Two pathological variants of RS are recognized: diffuse large B-cell lymphoma (DLBCL)-type and Hodgkin lymphoma (HL)-type RS. Different molecular mechanisms may explain the pathogenesis of DLBCL-type RS, including genetic lesions, modifications of immune regulators, and B cell receptor (BCR) pathway hyperactivation. Limited data are available for HL-type RS, and its development has been reported to be similar to de novo HL. In this review, we focus on the immune-related pathogenesis and immune system dysfunction of RS, which are linked to BCR over-reactivity, altered function of the immune system due to the underlying CLL, and specific features of the RS tumor microenvironment. The standard of care of this disease consists in chemoimmunotherapy, eventually followed by stem cell transplantation, but limited possibilities are offered to chemo-resistant patients, who represent the majority of RS cases. In order to address this unmet clinical need, several immunotherapeutic approaches have been developed, namely T cell engagement obtained with bispecific antibodies, PD-1/PD-L1 immune checkpoint blockade by the use of monoclonal antibodies, selective drug delivery with antibody-drug conjugates, and targeting malignant cells with anti-CD19 chimeric antigen receptor-T cells.

Risk of second primary malignancies in patients with chronic lymphocytic leukemia: a population-based study in the Netherlands, 1989-2019

The longevity of patients with chronic lymphocytic leukemia (CLL) has improved progressively over the past decades, making it essential to understand long-term health outcomes, such as second primary malignancies (SPMs). Therefore, this nationwide, population-based study assessed the risk of SPM development in CLL patients diagnosed during 1989-2019 in the Netherlands compared to the expected number of malignancies in an age-, sex-, and period-matched group from the general Dutch population. In 24,815 CLL patients followed for 162,698.49 person-years, 4369 SPMs were diagnosed with a standardized incidence ratio (SIR) of 1.63 (95% confidence interval [CI] 1.59-1.68). This elevated risk was observed for solid (SIR, 1.67; 95% CI, 1.65-1.75) and hematological SPMs (SIR 1.42; 95% CI, 1.24-1.62). The highest risk for SPMs was noted beyond five years post-diagnosis (SIR, 1.70; 95% CI, 1.62-1.77), for male individuals (SIR, 1.70; 95% CI, 1.64-1.77), and patients aged 18-69 years (SIR, 1.92; 95% CI, 1.79-2.05). The risk of SPMs was higher in CLL patients who received anti-neoplastic therapy (SIR, 2.12; 95% CI, 1.96-2.28), as compared with those who did not (SIR, 1.58; 95% CI, 1.53-1.63). Routine surveillance activities and tailored interventions to counteract the increased morbidity and excess mortality associated with SPMs are essential for improving long-term outcomes in CLL patients.

Monoclonal B-cell Lymphocytosis - a review of diagnostic criteria, biology, natural history, and clinical management

Since first described almost two decades ago, there has been significant evolution in our definition and understanding of the biology and implications of monoclonal B-cell lymphocytosis (MBL). This review provides an overview of the definition, classification, biology, and natural history of MBL, mainly focused on the dominant CLL-like phenotype form of MBL. The increasingly recognized implications of MBL with respect to immune dysfunction are discussed, particularly in view of the COVID-19 pandemic, along with management recommendations for MBL in the clinic.

Improving outcomes for patients with lymphoma: design and development of the Australian and New Zealand Lymphoma and Related Diseases Registry

Background

Lymphoma is a malignancy of lymphocytes and lymphoid tissues comprising a heterogeneous group of diseases, with up to 80 entities now described. Lymphoma is the 6^th most common cancer in Australia, affecting patients of all ages, with rising incidence rates. With the proliferation of efficacious novel agents, therapeutic strategies are increasingly diverse and survival is improving. There is a clear need for contemporary robust and detailed data on diagnostic, investigational and management strategies for this disease in Australia, New Zealand and worldwide, to inform and benchmark local and international standards of care. Clinical quality registries can provide these data, and support development of strategies to address variations in management, including serving as platforms for clinical trials and other research activities. The Lymphoma and Related Diseases Registry (LaRDR) was developed to capture details of patient demographics, disease characteristics, and management throughout their disease course and therapy and to develop outcome benchmarks nationally and internationally for lymphoma. This report describes the aims, development and implementation of the LaRDR, as well as challenges addressed in the process.

Methods

The LaRDR was established in 2016 as a multicentre, collaborative project at sites across Australia with a secure online database which collects prospective data on patients with a new diagnosis of lymphoma or chronic lymphocytic leukaemia (CLL). LaRDR development required multidisciplinary participation including specialist haematology, information technology, and biostatistical support, as well as secure funding. Here we describe the database development, data entry, ethics approval process, registry governance and support for participating sites and the coordinating centre.

Results

To date more than 5,300 patients have been enrolled from 28 sites in Australia and New Zealand. Multiple challenges arose during the development, which we describe, along with approaches used to overcome them. Several confirmed international collaborations are now in place, and the registry is providing valuable data for clinicians, researchers, industry and government, including through presentations of results at major national and international conferences.

Conclusion

Challenges in establishing the LaRDR have been successfully overcome and the registry is now a valuable resource for lymphoma clinicians, researchers, health economists and others in Australia, New Zealand and globally.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01728-0.