D. Dierickx MD, PhD

Primary vitreoretinal lymphoma: Single centre experience and review of literature

SUMMARY

BACKGROUND: Primary vitreoretinal lymphoma (PVRL) is a rare and difficult to diagnose lymphoma. The goal of this retrospective monocentric study was to obtain clinical characteristics, to evaluate median time to diagnosis, different treatment modalities and survival outcomes.

METHODS: PVRL cases were selected from the database of the University Hospitals Leuven (Belgium) from 1^st January 2012 until 1^st January 2021. A review of the available literature was performed.

RESULTS: We included eleven cases of PVRL with a median age of 76 years (Interquartile range (IQR): 68–81). Median time to diagnosis was seven months (Range: 3–16). Presenting symptoms were blurred vision (n=11, 100%) and floaters (n=3, 27%). Bilateral eye involvement was seen in 42% (n=5). Diagnosis was made by vitrectomy and immunocytochemistry in all cases. Histopathological diagnosis was diffuse large B-cell lymphoma in all cases. Flow cytometry was used in 55% (n=6) of patients to confirm diagnosis. Initial treatment included local therapy in all patients. A combination of local and systemic therapy was given to three patients (27%). Seven patients (64%) were diagnosed with CNS relapse. No systemic relapse was seen. Median progression-free survival (PFS) and overall survival (OS) were ten (IQR: 6–32) and 26 months (IQR: 12–37). Median PFS of patients treated with local versus combined therapy was 9.7 and 18 months, respectively. However, OS of patients with local versus combination therapy was 29 and 19 months, respectively.

CONCLUSION: We analysed the clinical characteristics of eleven patients with PVRL in our hospital. The majority of these cases will eventually progress to CNS lymphoma. We saw a prolonged PFS for patients treated with combination therapy in first-line, compared to local therapy alone. However, OS was longer in patients treated with local therapy only. Despite the small cohort, these results are comparable to previous literature. Based on larger retrospective studies we conclude that local therapy as first line treatment in PVRL results in similar OS rates with less systemic toxicity compared to combination therapy.

(BELG J HEMATOL 2022;13(6):228–235)

Immunity, the Epstein-Barr virus and the microenvironment in lymphoma

SUMMARY

Immune regulation therapy or ‘immunotherapy’ has been a major evolution in the field of cancer therapy in the last decade. The goal of this thesis was to better characterise multiple rare lymphoproliferative disorders in order to guide therapy development, predictive biomarker discovery and ultimately help ensuring that these novel therapies can get to the patients who stand to benefit from them. Many lymphoma types arise in a context of altered immune system function with potential implications for immunotherapy. One example of lymphoma arising in the context of chronic immune stimulation is Helico bacter Pylori infection, which is known as mucosa associated lymphoid tissue (MALT) lymphoma of the stomach. For this lymphoma we reviewed the literature and described how it is an excellent model to understand lymphomas arising in an immune stimulated context.¹ Other lymphomas arise in a context of immunosuppression, of which post-transplant lymphoproliferative disorders (PTLD) are the best characterised. Besides the immune state, the presence of a virus such as the Epstein-Barr virus has major effects on lymphomas and their (immune) microenvironment with potential impact on immunotherapy. A review of EBV-related effects on PTLDs was done.² Lymphoproliferative disorder’s (LPDs) arising in the context of treatment with immunomodulatory (IM)/immunosuppressive (IS) drugs for various auto-immune diseases are lesser-known. These are called immunomodulation related lymphoproliferative disorders (IARLPD). For this thesis, we characterised one of the largest single centre case series of IARLPD.³ Finally, some lymphomas arise in specific ‘immune-privileged’ sites such as the central nervous system (CNS) called Primary central nervous system lymphoma (PCSNL). Digital slide analysis method and the novel MILAN multiplex staining technique were used to study the tumour microenvironment (TME) in PCNSL confirming the relevance of the microenvironment in the clinical behaviour of this lymphomas, highlighting potential relevance of immunotherapy and confirming the usefulness of the mentioned techniques in the study of the TME.⁴ For the purpose of this dissertation presentation we will focus primarily on this latter work.

(BELG J HEMATOL 2021;12(6):280-2)

EBV-induced double hit transformation of splenic (marginal zone) lymphoma, in a patient with a chronic Hepatitis B virus hepatitis

SUMMARY

We report a case of an EBV-induced large-cell transformation of a splenic marginal zone lymphoma in an 81-year-old female with a simultaneous finding of hepatitis B viral infection.

(BELG J HEMATOL 2021;12(6):275-9)

Diagnosis and treatment of thrombotic thrombocytopenic purpura

SUMMARY

Thrombotic thrombocytopenic purpura (TTP) is a rare and life-threatening thrombotic microangiopathic disorder (TMA) due to a severe deficiency of ADAMTS13 (A Disintegrin And Metalloprotease with Thrombo-Spondin type 1 repeats, member 13). The deficiency in ADAMTS13 can either be caused by mutations in ADAMTS13 (congenital TTP or Upshaw-Schulman syndrome, cTTP) or by anti-ADAMTS13 autoantibodies (immune-mediated TTP, iTTP). Diagnosis of TTP is challenging but crucial for the survival of the patient. TTP should be suspected when microangiopathic haemolytic anaemia and severe thrombocytopenia are observed. A severely decreased ADAMTS13 activity (activity <10%) should confirm the diagnosis of TTP. Standard treatment of TTP is plasma therapy (plasma exchange for iTTP, while plasma infusion for cTTP), but novel therapeutics like rituximab, caplacizumab and recombinant ADAMTS13 show promising results regarding the recovery and sustained remission of TTP patients. However, although major advances have been made in the management of TTP, TTP is a chronic disease and patients still relapse, careful and stringent patient follow-up is needed to improve the patients’ quality of life.

(BELG J HEMATOL 2020;11(6):253-60)

Oxaliplatin-induced immune mediated haemolytic anaemia, thrombocytopenia and renal failure

SUMMARY

Oxaliplatin-based chemotherapy is commonly used to treat colorectal cancer. After prolonged administration it can rarely lead to hypersensitivity reactions such as immune mediated haemolytic anaemia and thrombocytopenia. We present the case of a 50-year old patient admitted with acute onset of fever, dark urine and back pain during the ninth infusion of oxaliplatin. Two weeks before the current event he experienced similar though less severe symptoms. Laboratory signs were compatible with severe Coombs positive haemolytic anaemia, thrombocytopenia and acute kidney injury. Signs of haemolysis abated quickly, however, the patient developed anuria and required dialysis for thirty days. Immune mediated haemolytic anaemia is a rare but potentially life-threatening complication of prolonged oxaliplatin therapy, especially when kidney failure develops. A careful history and high index of suspicion may identify warning signs leading to increased vigilance and possible prevention of such events.

(BELG J HEMATOL 2020;11(3):128–32)

The role of immunotherapy in the treatment of classic Hodgkin lymphoma

SUMMARY

Classic Hodgkin lymphoma (cHL) is one of the most frequent lymphomas in the Western world. Its incidence has a bimodal distribution with the most important peak arising in the age group of children and adolescents and a second less prominent peak in the elderly. Until recently, therapeutic options consisted solely of chemotherapy and/or radiotherapy. Despite the achievement of relatively high cure rates with these regimens, long-term toxicity remains a great concern. Moreover, patients that relapse or are refractory to these treatments generally have a poor prognosis despite the fact that autologous or allogeneic stem cell transplantation are options in fit patients. In the last decade, increased understanding of the pathobiology of Hodgkin lymphoma has led to the identification of several molecular targets for new therapeutic agents. Several of these molecules (i.e. brentuximab vedotin, nivolumab and pembrolizumab) have already proven their benefit in clinical trials and were subsequently approved by the US Food and Drug administration (FDA) and the European Medicine Agency (EMA) as safe and efficacious therapies for relapsed or refractory (R/R) cHL. Further results of randomised controlled trials (RCTs) are awaited to determine if these therapies also have a place in first-line. In the meantime, several other novel agents – ranging from checkpoint inhibitors to antibody-based drugs and cellular therapies – are being tested in clinical and preclinical studies. In this review we present an overview of the most important types of immunotherapies that are currently being used in the treatment of cHL or who demonstrated promising therapeutic potential.

(BELG J HEMATOL 2019;10(8):320–5)

03 Renal allograft function following treatment of post-transplant lymphoproliferative disorder