Annual clinical updates in hematological malignancies: a continuing medical education series. Hodgkin lymphoma: 2011 update on diagnosis, risk-stratification, and management

Apoptotic regulator BCL-2 blockade as a potential therapy in classical Hodgkin Lymphoma

The challenge in classical Hodgkin Lymphoma (cHL) management is the 30-40% of refractory/relapsed cases.

AIMS

The aim of this work was to determine whether NIK and BCL-2 could be useful as prognosis biomarkers in cHL. In addition, we evaluated BCL-2 as a directed-therapy in cHL cell lines using venetoclax.

MAIN METHODS

We evaluated NIK and BCL-2 expression in 112 untreated cHL patients' lymph-node biopsies by immunohistochemistry. cHL cell lines were treated with venetoclax alone or combined with vincristine or doxorubicin. Cell viability, metabolic activity and cell death were analyzed by trypan-blue exclusion method, MTS assay and FDA/IP staining respectively.

KEY FINDINGS

No correlation between NIK or BCL-2 expression and the majority of the clinical parameters was found. Patients with ≥60% BCL-2+ HRS-cells had a shorter disease-free survival (DFS) and overall survival (OS) (p = 0.002, p = 0.02 respectively). A decision tree analysis, in a 30 patients subgroup, showed that patients with <60% NIK+ HRS-cells but with ≥60% BCL-2+ HRS-cells had a worse outcome in terms of DFS and OS. These parameters performed better as prognosis indicators as compared to the diagnosis bone marrow status. Human cHL cell lines U-H01, KM-H2, L1236, SUPHD1, L540 showed sensitivity to venetoclax. The co-treatment effect of venetoclax and vincristine or doxorubicin on cell viability was diverse depending on the cell line evaluated.

SIGNIFICANCE

BCL-2 should be considered as a prognosis biomarker as well as a potential new therapeutic target in cHL. We report for the first time the cytotoxic effect of venetoclax in human cHL cell lines.

Lymphoma-associated dysimmune polyneuropathies

Lymphoma consists of a variety of malignancies of lymphocyte origin. A spectrum of clinical peripheral neuropathy syndromes with different disease mechanisms occurs in about 5% of lymphoma patients. There exists a complex inter-relationship between lymphoproliferative malignancies and autoimmunity. An imbalance in the regulation of the immune system presumably underlies various immune-mediated neuropathies in patients with lymphoma. This article reviews lymphoma and more-or-less well-defined dysimmune neuropathy subgroups that are caused by humoral and/or cell-mediated immune disease mechanisms directed against known or undetermined peripheral nerve antigens.

Epstein-Barr virus-positive nodular lymphocyte predominant Hodgkin lymphoma

Hodgkin lymphoma (HL) is classified into 2 largely distinct subgroups, namely nodular lymphocyte predominant HL (NLPHL) and classic HL (CHL). CHL is further divided into nodular sclerosis, lymphocyte-rich, mixed cellularity (MCCHL) and lymphocyte-depleted (LDCHL) subtypes. In industrialized nations, Epstein-Barr virus (EBV) has been associated with all types of CHL, especially the MCCHL and LDCHL subtypes, but is rare in NLPHL. We report 8 cases of EBV-positive NLPHL occurring in patients in the United States. All 8 patients have no history of immunosuppression and presented with localized or systemic lymphadenopathy. Histologically, 6 cases had a vaguely nodular pattern and 2 cases had a nodular and diffuse pattern. In all cases, lymphocyte predominant (LP) cells were observed in a background of small lymphocytes and histiocytes. Immunohistochemical analysis showed that the LP cells in all cases were positive for CD20, CD79a, PAX5, OCT2, and CD45 and were negative for CD15. CD30 was expressed variably in 7 cases. EBV encoded RNA was present in all LP cells in 5 cases and in a subset of LP cells in 3 cases. One patient was treated with radiation therapy and 7 patients received chemotherapy, including 4 of 7 patients who underwent autologous stem cell transplantation. EBV infection is a rare primary or secondary event in NLPHL that correlates with poorer prognosis and often requires more aggressive therapy. The variable expression of CD30 in most of these cases could be the result of EBV infection.

Progress in the initial management of Hodgkin's Lymphoma

Hodgkin lymphoma (HL) is an uncommon B-cell lymphoid malignancy composed of two distinct disease entities; the more commonly diagnosed classical HL and the rare nodular lymphocyte predominant HL. Nodular sclerosis, mixed cellularity, lymphocyte depletion, and lymphocyte-rich HL are subgroups under the designation of classical HL. An accurate assessment of the stage of disease in patients with HL is critical for the selection of appropriate therapy. Prognostic models that identify patients at low or high risk for recurrence are used to optimize therapy for patients with limited or advanced stage disease and predict their outcomes while reducing the toxicities. Initial therapy for HL patients is based on the histology, anatomical stage and the presence of poor prognostic features. Management of localized HL has shifted from radiation alone to combined modality strategies with brief courses of combination chemotherapy followed by involved-field radiation therapy. Patients with advanced stage disease receive a longer course of chemotherapy commonly without radiation therapy. Clinical trials are being conducted using the early interim response or response at the end of therapy as measured by PET scan to determine treatment.

Brentuximab vedotin: a new age in the treatment of Hodgkin lymphoma and anaplastic large cell lymphoma

OBJECTIVE

To review the clinical trial data, pharmacology, pharmacokinetics, and adverse effects of brentuximab vedotin.

DATA SOURCES

A literature search was performed using MEDLINE and PubMed (both 1966-October 2011), as well as the American Society of Hematology abstracts (2000-January 2012), using the primary search terms brentuximab vedotin, SGN-35, Hodgkin lymphoma (HL), and anaplastic large cell lymphoma (ALCL).

STUDY SELECTION AND DATA EXTRACTION

Published and ongoing clinical studies and abstracts in the English language that detail the pharmacology, pharmacokinetics, safety, and clinical efficacy of brentuximab vedotin in the treatment of HL and ALCL were included in this review.

DATA SYNTHESIS

Brentuximab vedotin is an antibody drug conjugate that combines the anti-CD30 antibody, cAC10, with the synthetic tubulin disrupting agent monomethyl auristatin E. A Phase 1 trial in patients with relapsed and refractory HL or systemic ALCL supported a dose of 1.8 mg/kg every 3 weeks. The drug was well tolerated, with the majority of adverse reactions being grade 1 or 2 in severity. Common toxicities included fatigue, pyrexia, diarrhea, nausea, neutropenia, and peripheral neuropathy. Phase 2 studies in the same patient populations illustrated objective response rates of 73-86% with an acceptable toxicity profile. Based on results of these Phase 2 trials, the Food and Drug Administration granted approval of brentuximab vedotin in August 2011 for the treatment of relapsed and refractory HL or ALCL.

CONCLUSIONS

Phase 1 and 2 clinical trial data indicate that brentuximab vedotin is efficacious and safe in patients with relapsed and refractory CD30-positive lymphomas. This agent is being investigated in combination with chemotherapy to further elucidate its role in lymphoma therapy.