Second primary malignancies in patients with lymphoma in Denmark after high-dose chemotherapy and autologous haematopoietic stem-cell transplantation: a population-based, retrospective cohort study

Second primary non-myeloid malignancies following intensive treatment for adult acute myeloid leukaemia: a Danish population-based cohort study

Background

Second primary malignancies (SPMs) are a well-known, long-term complication of antineoplastic treatment. This nationwide cohort study examined the risk of non-myeloid SPMs in survivors of adult acute myeloid leukaemia (AML) treated with intensive chemotherapy and, in some cases, allogeneic stem cell transplantation (alloSCT), compared to a matched general population.

Methods

Patients with incident AML between 2000 and 2018, alive and aged 18-70 years two years after start of intensive chemotherapy, were included and matched 1:10 to comparators from the general Danish population on sex, age, and the Nordic Multimorbidity Index. Exclusion criteria were non-myeloid SPMs for both AML survivors and comparators.

Findings

A total of 750 AML survivors and 7500 comparators were followed for a median of 10.6 years. The hazard ratio (HR) of non-myeloid SPMs was 1.55 (95% confidence interval [CI] 1.27-1.89) for AML survivors compared to comparators, driven by non-melanoma skin cancer (HR 2.52, 95% CI 1.90-3.35), not of solid cancer (HR 1.14, 95% CI 0.87-1.49). The 10-year cumulative incidences of any non-myeloid SPM were 13.5% (95% CI 10.6-16.5%) in AML survivors and 11.9% (95% CI 11.1-12.8%) in matched comparators. Additionally, AML survivors consolidated with alloSCT had a higher hazard rate of non-myeloid SPMs compared to non-transplanted AML survivors (adjusted HR 1.50, 95% CI 1.00-2.26).

Interpretation

The increased rate of non-myeloid SPMs observed in this population-based cohort study of AML survivors was almost entirely driven by non-melanoma skin cancer and is thus outweighed by the importance of intensive chemotherapy.

Funding

Svend Andersen, Heinrich Kopps, and Karen Elise Jensen's Foundation.

T-cell neoplasias and secondary malignancies after CAR-T cell therapy: current knowledge, risk factors, and implications from CAR-T engineering strategies

Widespread use of CAR-T cell therapies for treatment of B cell malignancies has resulted in a frameshift in treatment strategies and improved patient outcomes since the first CAR-T product was FDA approved in 2017. Currently over 30,000 patients have been treated with approved CAR-T cell products, with many more likely to be treated in future, both as standard of care therapy as well as on clinical trials. As more patients are treated, development of rare complications has begun to emerge, and the incidence of second primary malignancies after CAR-T cell therapy is evolving from a hypothetical to a realized concern. Furthermore, in November 2023, the FDA issued a warning regarding the potential for CAR-T cell-derived T cell neoplasias to arise as a result of CAR-T manufacturing. Here we review patient risk factors for development of second primary malignancies including T cell neoplasias, CAR-T engineering strategies that may increase this risk, and the current body of literature surrounding incidence of second primary malignancies and case reports of T cell neoplasias arising after CAR-T cell therapy.

Long-term safety of lentiviral or gammaretroviral gene-modified T cell therapies

Long-term risks of gene therapy are not fully understood. In this study, we evaluated safety outcomes in 783 patients over more than 2,200 total patient-years of observation from 38 T cell therapy trials. The trials employed integrating gammaretroviral or lentiviral vectors to deliver engineered receptors to target HIV-1 infection or cancer. Eighteen patients (2.3%) developed secondary malignancies after treatment, with a median onset of 1.94 years (range: 51 d to 14 years). Where possible, incident tumor samples were analyzed for vector copy number, revealing no evidence of high-level marking or other indications of insertional mutagenesis. One T cell lymphoma was detected, but malignant T cells were not marked by vector integration. Analysis of vector integration sites in 176 patients revealed no pathological insertions linked to secondary malignancies, although, in some cases, integration in or near specific genes, including tumor suppressor genes, was associated with modest clonal expansion and sustained T cell persistence. These findings highlight the safety of engineered T cell therapies.

Second Primary Cancer After Chimeric Antigen Receptor-T-Cell Therapy: A Review

Importance

The commercialization of chimeric antigen receptor-T-cell (CAR-T) therapy has changed the landscape of treatment of hematological cancers. Numerous studies from the early 2000s paved the way for cell-based targeted therapeutics, which have been established as practice-changing therapies in lymphoma, leukemia, and multiple myeloma. However, there has been some recent concern about the risk for second primary cancers (SPCs).

Observations

Multiple cases of SPCs arising after CAR-T therapy have been reported to the US Food and Drug Administration. Most SPCs have been negative for the chimeric antigen receptor transgene, with rare reports of transgene-positive cancers. This review summarizes the most salient literature on epidemiology and pathobiology of SPCs after CAR-T therapy. Additionally, a discussion is provided on potential mitigation strategies for SPCs after CAR-T therapies.

Conclusions and Relevance

The results of this review suggest that there are limited data to suggest that inadvertent transgene insertion is associated with SPCs in the post-CAR-T setting. Nonetheless, evidence-based practical solutions and scientific strategies for risk mitigation can be implemented. These include optimization of T-cell manufacturing, application of safer synthetic immunobiology, and implementation of high-fidelity genomic testing, including baseline screening for clonal hematopoiesis. These strategies may inform optimal design of the next generation of CAR-T products that confer minimal risk for SPCs such that the risk-benefit profile remains favorable to proceed with CAR-T administration for eligible patients.

Second Primary Malignancies after CAR T-Cell Therapy: A Systematic Review and Meta-analysis of 5,517 Lymphoma and Myeloma Patients

PURPOSE

Chimeric antigen receptor (CAR) T-cell therapy is a potent immunotherapy for hematologic malignancies, but patients can develop long-term adverse events, including second primary malignancies (SPM) that impact morbidity and mortality. To delineate the frequency and subtypes of SPMs following CAR-T in lymphoma and myeloma, we performed a systematic review and meta-analysis.

EXPERIMENTAL DESIGN

A literature search was conducted in the MEDLINE, Embase, and Cochrane CENTRAL databases. Following the extraction of SPM cases and assignment of malignant origin, we analyzed SPM point estimates using random effects models.

RESULTS

We identified 326 SPMs across 5,517 patients from 18 clinical trials and 7 real-world studies. With a median follow-up of 21.7 months, the overall SPM point estimate was 6.0% (95% confidence interval, 4.8%-7.4%). SPM estimates were associated with treatment setting (clinical trials > real-world studies), duration of follow-up, and number of prior treatment lines, which were each confirmed as independent study-level risk factors of SPM in a meta-regression model. A subgroup meta-analysis of the four trials that randomized CAR-T versus standard-of-care revealed a similar risk of SPM with either treatment strategy (P = 0.92). In a distribution analysis of SPM subtypes, hematologic malignancies were the most common entity (37%), followed by solid tumors (27%) and non-melanoma skin cancers (16%). T-cell malignancies represented a small minority of events (1.5%). We noted disease- and product-specific variations in SPM distribution.

CONCLUSIONS

These data raise awareness of SPM as a clinically relevant long-term adverse event in patients receiving CAR T-cell therapy. However, our findings do not indicate that SPM frequency is higher with CAR-T versus previous standard-of-care strategies.

Secondary primary malignancies after CD-19 directed CAR-T-cell therapy in lymphomas: A report from the Italian CART-SIE study

Secondary primary malignancies (SPM) have been reported after anti-BCMA or anti-CD19 chimeric antigen receptor (CAR)-T-cell therapies. While the cytotoxic effect of antecedent therapies, including chemotherapy and radiotherapy, has been well established, few data are available on risk related to CAR-T immunotherapies. The study aimed to analyse the incidence of SPM in 651 patients enrolled in the Italian prospective observational CART-SIE study. SPMs were documented in 4.3% (28/651), and the most frequent SPMs were haematological malignancies. In conclusion, the frequency of SPMs in our cohort of heavily pretreated patients receiving CAR-T was relatively low and consistent with previous studies.

Current understanding and management of CAR T cell-associated toxicities

Chimeric antigen receptor (CAR) T cell therapy has revolutionized the treatment of several haematological malignancies and is being investigated in patients with various solid tumours. Characteristic CAR T cell-associated toxicities such as cytokine-release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) are now well-recognized, and improved supportive care and management with immunosuppressive agents has made CAR T cell therapy safer and more feasible than it was when the first regulatory approvals of such treatments were granted in 2017. The increasing clinical experience with these therapies has also improved recognition of previously less well-defined toxicities, including movement disorders, immune effector cell-associated haematotoxicity (ICAHT) and immune effector cell-associated haemophagocytic lymphohistiocytosis-like syndrome (IEC-HS), as well as the substantial risk of infection in patients with persistent CAR T cell-induced B cell aplasia and hypogammaglobulinaemia. A more diverse selection of immunosuppressive and supportive-care pharmacotherapies is now being utilized for toxicity management, yet no universal algorithm for their application exists. As CAR T cell products targeting new antigens are developed, additional toxicities involving damage to non-malignant tissues expressing the target antigen are a potential hurdle. Continued prospective evaluation of toxicity management strategies and the design of less-toxic CAR T cell products are both crucial for ongoing success in this field. In this Review, we discuss the evolving understanding and clinical management of CAR T cell-associated toxicities.