Immune Response against ALK in Children with ALK-Positive Anaplastic Large Cell Lymphoma

Diagnosis and management of ALK-positive anaplastic large cell lymphoma in children and adolescents

Anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL) is a CD30-positive T cell lymphoma characterized by signalling from constitutively activated ALK fusion proteins. Most children and adolescents present in advanced stages, often with extranodal disease and B symptoms. The current front-line therapy standard of six cycles polychemotherapy reaches an event-free survival of 70%. The strongest independent prognostic factors are minimal disseminated disease and early minimal residual disease. At relapse, ALK-inhibitors, Brentuximab Vedotin, Vinblastine, or second line chemotherapy are effective re-inductions. Survival at relapse exceeds 60-70% with consolidation according to the time of relapse (Vinblastine monotherapy or allogeneic hematopoietic stem cell transplantation) so that the overall survival reaches 95%. It needs to be shown whether check-point inhibitors or long-term ALK-inhibition may substitute for transplantation. The future necessitates international cooperative trials testing whether a shift of paradigm to a chemotherapy-free regimen can cure ALK-positive ALCL.

A challenging case of ALK-negative anaplastic large cell lymphoma in a 12-year-old boy: A rare case report from Syria

Introduction and importance

Anaplastic Large-cell Lymphoma (ALCL) is a rare but aggressive type of NHL that develop from mature post-thymic T-cells. ALCL constitutes approximately 2% of all lymphoid neoplasm. It is typically found among children and young adults, accounting for 10–15% of pediatric NHL, compared to 2% of adult NHL.

Case presentation

A 12-year-old Syrian boy was admitted to our hospital due to epistaxis, anorexia, weight loss and night sweats. The physical examination revealed preauricular, postauricular and submandibular lymphadenopathy. Pathological examination of the biopsy suggested Classical Hodgkin Lymphoma. Later on, Immunohistochemistry staining confirmed the diagnosis of ALK-negative Anaplastic Large Cell Lymphoma.

Clinical discussion

Systemic ALCL can be categorized into two major groups based on the expression of Anaplastic Lymphoma Kinase (ALK) protein: Systemic ALK + positive and Systemic ALK-negative. The majority of pediatric cases show an overexpression of (ALK), however, pediatric ALK-negative ALCL can occur in rare cases.

Conclusion

The aim of this article is to report a rare case of pediatric ALK-negative anaplastic large cell lymphoma that developed a rapid & aggressive growth within a few months despite the chemotherapy treatment and unfortunately led to the patient's death.

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Anaplastic large cell lymphoma (ALCL) is a rare type of non-Hodgkin lymphoma and one of the subtypes of T cell lymphoma.

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ALK-negative ALCL is rare among children and has a poor prognosis.

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Establishing ALCL diagnosis is challenging due to the similarities with CHL, DLBCL and PTCL-NOS.

The Dual Role of Autophagy in Crizotinib-Treated ALK+ ALCL: From the Lymphoma Cells Drug Resistance to Their Demise

Autophagy has been described as harboring a dual role in cancer development and therapy. Depending on the context, it can exert either pro-survival or pro-death functions. Here, we review what is known about autophagy in crizotinib-treated ALK⁺ ALCL. We first present our main findings on the role and regulation of autophagy in these cells. Then, we provide literature-driven hypotheses that could explain mechanistically the pro-survival properties of autophagy in crizotinib-treated bulk and stem-like ALK⁺ ALCL cells. Finally, we discuss how the potentiation of autophagy, which occurs with combined therapies (ALK and BCL2 or ALK and RAF1 co-inhibition), could convert it from a survival mechanism to a pro-death process.

Stem Cell Transplantation and Vinblastine Monotherapy for Relapsed Pediatric Anaplastic Large Cell Lymphoma: Results of the International, Prospective ALCL-Relapse Trial

PURPOSE

To analyze the efficacy of a risk-stratified treatment of children with relapsed anaplastic large cell lymphoma (ALCL). The ALCL-Relapse trial (ClinicalTrials.gov identifier: NCT00317408 ) stratified patients according to the time of relapse and CD3 expression to prospectively test reinduction approaches combined with consolidation by allogeneic or autologous hematopoietic stem cell transplantation (SCT) and vinblastine monotherapy.

PATIENTS AND METHODS

Patients with progression during frontline therapy (very high risk) or a CD3-positive relapse (high risk) were scheduled for allogeneic SCT after reinduction chemotherapy. Patients with a CD3-negative relapse within 1 year after initial diagnosis or prior exposure to vinblastine (intermediate risk) received autologous SCT after carmustine-etoposide-cytarabine-melphalan. This arm was terminated prematurely, and subsequent patients received vinblastine monotherapy instead. Patients with a CD3-negative relapse > 1 year after initial diagnosis (low risk) received vinblastine monotherapy.

RESULTS

One hundred sixteen patients met the inclusion criteria; 105 evaluable patients with CNS-negative disease had a 5-year event-free survival (EFS) of 53% ± 5% and a 5-year overall survival (OS) of 78% ± 4%. Before termination of autologous SCT, EFS rates of patients in the very-high- (n = 17), high- (n = 26), intermediate- (n = 32), and low- (n = 21) risk groups were 41% ± 12%, 62% ± 10%, 44% ± 9%, and 81% ± 9%; the respective OS rates were 59% ± 12%, 73% ± 9%, 78% ± 7%, and 90% ± 6%. Analyzing only the patients in the intermediate-risk group consolidated per protocol by autologous SCT, EFS and OS of 23 patients were 30% ± 10% and 78% ± 9%, respectively. All 5 patients with intermediate risk receiving vinblastine monotherapy after the amendment experienced relapse again.

CONCLUSION

Shorter time to relapse was the strongest predictor of subsequent relapse. Allogeneic SCT offers a chance for cure in patients with high-risk ALCL relapse. For early relapsed ALCL autologous SCT was not effective. Vinblastine monotherapy achieved cure in patients with late relapse; however, it was not effective for early relapses.

NPM-ALK-reactive T-cell responses in children and adolescents with NPM-ALK positive anaplastic large cell lymphoma

The oncoantigen nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) induces cellular and humoral immune responses in patients with NPM-ALK-positive anaplastic large cell lymphoma (ALCL). We characterize the NPM-ALK-specific T-cell responses in a cohort of pediatric and adolescent ALCL-patients in remission without Human Leucocyte Antigen (HLA)-preselection.

First, we assessed NPM-ALK-reactive T-cell responses and their HLA-class I restriction in patients by using dendritic cells (DCs) transfected with in vitro transcribed (IVT) NPM-ALK-RNA for CD8 (n = 20) or CD3 (n = 9) T-cell stimulation. NPM-ALK-specific T-cells were detected in twelve of 29 patients (nine of 20 with CD8-selected and three of nine with CD3-selected cells). Recognition of NPM-ALK was restricted by HLA-C alleles in six of eight, and by HLA-B alleles in four of eight analyzed patients. No NPM-ALK-reactivity was detected in 20 healthy individuals.

Second, in order to define possible immunogenic NPM-ALK-epitope regions, DCs pulsed with pools of overlapping long NPM-ALK-peptides were used to stimulate T-cells in further 22 patients and ten controls. Responsive T-cells were detected in 15 patients and in five controls. A peptide pool located in the middle of the kinase domain induced ALK-reactive T-cells in 14 of 15 responsive patients. We could narrow to single peptides between p327-p370 of NPM-ALK in four patients.

In conclusion, using IVT-RNA, 40% of NPM-ALK-positive ALCL-patients in remission had detectable NPM-ALK-specific T-cell responses which were mainly restricted by HLA-B and -C alleles. Peptide stimulation of T-cells revealed responses in almost 70% of patients and allowed describing an immunogenic region located in the ALK-kinase domain.

Novel targeted therapeutic agents for the treatment of childhood, adolescent and young adult non-Hodgkin lymphoma

Non-Hodgkin lymphomas (NHLs) are a heterogeneous group of malignancies. Most NHLs in children, adolescent and young adult patients are aggressive lymphomas that are generally treated with multi-agent chemotherapy or immunochemotherapy regimens. While overall survival is high, the treatment can lead to a high rate of acute and long-term toxicity. However, in the rarer instance of relapsed or refractory disease, outcomes are dismal. Novel therapeutic approaches to the treatment of both T-cell and B-cell NHLs are critical to improve outcomes while also minimising the associated toxicity of current treatment regimes. Potential therapeutic approaches in development include humoral and cellular immunotherapies, small molecule inhibitors of relevant signalling pathways and epigenetic modifying agents. In this review, we will highlight the current state of development of agents of interest with a focus on agents relevant to childhood, adolescent and young adult NHL.