CD30 expression in peripheral T-cell lymphomas

Peripheral T-cell lymphoma, not otherwise specified

Peripheral T-cell lymphoma, not otherwise specified, is a broad category of biologically and clinically heterogeneous diseases that cannot be further classified into any other of the existing entities defined by the World Health Organization classification. Anthracycline-containing regimens, namely cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), nowadays represent the standard first-line treatment; for patients who achieve a satisfactory response, a consolidation by means of autologous stem cell transplantation may offer a greater chance of long-term survival. Several patients, however, display treatment refractoriness or relapse soon after obtaining a response, and just a few of them are suitable transplant candidates. This is why several new agents, with innovative mechanisms of action, have been investigated in this context: pralatrexate, romidepsin, belinostat, and brentuximab vedotin have been approved for relapsed and refractory peripheral T-cell lymphomas based on their activity, although they do not significantly affect survival rates. The incorporation of such new drugs within a CHOP backbone is under investigation to enhance response rates, allow a higher proportion of patients to be transplanted in remission, and prolong survival.

Prognostic significance of CD30 expression in nasal natural killer/T-cell lymphoma

The present study aimed to investigate the expression of tumor necrosis factor receptor superfamily member 8 (CD30) in extranodal natural killer/T-cell lymphoma (ENKTL) using immunohistochemistry, and to evaluate the association between CD30 and clinicopathological and prognostic significance. CD30 expression was detected using immunohistochemistry on paraffin-embedded sections obtained from 122 patients with ENKTL prior to treatment. In total, 70 of these patients with complete clinical data were collected for prognostic analysis. The level of CD30 expression, of the 122 patients with ENKTL, was grouped on the basis of a 5-tiered scale as follows: 0%, no staining; 1+, <25% positive cells; 2+, 25-50% positive cells; 3+, 50-75% positive cells; and 4+, >75% positive cells). In total, 36 (29.5%) were classified as 0; 46 (37.7%) as 1+; 22 (18.0%) as 2+; 12 (9.8%) as 3+; and 6 (4.9%) as 4+. Among the 86 patients with scores between 1+ and 4+, the membranous staining patterns of CD30 expression were sporadic (33.7%), focal (43.2%), diffuse (15.1%) and angiocentric (8.1%). When considering a score of ≥3+ as CD30 positivity (CD30⁺), the CD30⁺ group had significantly shorter overall survival rates (P=0.0023) and progression-free survival rate (P=0.0008) compared with CD30 negative group. However, no statistically significant association was found between CD30 expression and clinicopathological features (P<0.05). The present study found that the expression of CD30 (≥3+) was significantly associated with poor prognosis but was not associated with clinical and histopathological parameters in ENKTL. Therefore, CD30 may be a useful prognostic marker in ENKTL.

Diagnostic, prognostic and therapeutic role of CD30 in lymphoma

INTRODUCTION

CD30 is a cell surface receptor expressed in classical Hodgkin lymphoma (HL), anaplastic large cell lymphoma (ALCL), and many other lymphomas to a variable degree. It has been identified as an important therapeutic target in lymphoma. Areas covered: CD30 testing is essential in diagnosis of classical HL and ALCL, and expression can also be seen in other lymphoma subtypes. Development of Brentuximab vedotin (BV), an antibody-drug conjugate directed to CD30, has been an important advance in lymphoma treatment. It is approved in treatment of relapsed HL and ALCL, as well as post-transplant maintenance for HL, and has been shown to be effective in other CD30-expressing lymphomas. This review describes the role of CD30 and the use of CD30-targeted agents in HL, ALCL, and other lymphomas, including review of relevant trials of BV. Expert commentary: Recognition of CD30 expression in lymphoma has led to the development of important therapeutic options. Multiple trials are ongoing combining BV with other agents, such as chemotherapy or immunotherapy, to develop more effective regimens. In addition, treatments targeting CD30 in different ways are being developed, such as bispecific antibodies and chimeric antigen receptor (CAR) T-cells.

How I manage peripheral T-cell lymphoma, not otherwise specified and angioimmunoblastic T-cell lymphoma: current practice and a glimpse into the future

Peripheral T-cell lymphoma (PTCL), not otherwise specified (NOS) and angioimmunoblastic T-cell lymphoma (AITL) are the most frequent of more than 20 mature PTCL entities featuring a broad spectrum of morphological, immunophenotypic, molecular and clinical characteristics. Unfortunately, recent progress in understanding the (epi)genetic background of PTCL has not been met with similar advances in treatment. Thus, CHO(E)P [cyclophosphamide, doxorubicin, vincristine, and prednisone (plus etoposide)] remains standard first-line therapy. Patients without comorbidities achieving complete or partial remission proceed to autologous stem cell transplantation. With this approach about 50% of patients survive long-term. Patients relapsing after or progressing during first-line therapy have a dismal prognosis. They receive salvage gemcitabine-therapy followed by allogeneic transplantation whenever possible. After allografting, approximately half of the patients survive long-term; any other treatment is palliative. New drugs investigated in phase II studies achieved response rates between 10% and 30%; long-term remissions are the exception to the rule. While most new drugs are not licensed and not readily available, a plethora of other innovative drugs targeting (epi-)genetic abnormalities are in early development. These, together with combinations of new and old drugs, will hopefully increase response to first-line therapy, bridge more patients to transplantation, and finally improve prognosis for all patients with PTCL.

T-cell Lymphomas: Updates in Biology and Diagnosis

Nodal-based peripheral T-cell lymphomas are heterogeneous malignancies with overlapping morphology and clinical features. However, the current World Health Organization classification scheme separates these tumors into prognostically relevant categories. Since its publication, efforts to uncover the gene expression profiles and molecular alterations have subdivided these categories further, and distinct subgroups are emerging with specific profiles that reflect the cell of origin for these tumors and their microenvironment. Identification of the perturbed biologic pathways may prove useful in selecting patients for specific therapies and associating biomarkers with survival and relapse.

Sclerosing Angiomatoid Nodular Transformation of the spleen, focal nodular hyperplasia and hemangioma of the liver: A tale of three lesions

Sclerosing Angiomatoid Nodular Transformation (SANT) of the spleen is a benign vascular lesion with peculiar histological features. The pathogenesis of SANT is still largely unknown and variable etiologies have been proposed, including autoimmune, inflammatory, and/or vascular disorders. The present report describes a unique case of splenic SANT, associated with focal nodular hyperplasia and a sclerosing hemangioma of the liver. The clinic-pathological features of such an unusual case are thoroughly illustrated. Its possible pathogenic mechanisms are also briefly addressed.

Clinical features, outcome and prognostic factors of 87 patients with angioimmunoblastic T cell lymphoma in Taiwan

We retrospectively analyzed 87 patients with angioimmunoblastic T cell lymphoma (AITL) in Taiwan. The median age was 68 (range 18-89) years. Of these patients, 74 % was at an advanced stage. The most common extra-nodal site involved was bone marrow (36 %). Of these patients, 77 % were International Prognostic Index (IPI) >1 and 79 % had a prognostic index for peripheral T-cell lymphoma (PIT) >1. Of 75 patients who received systemic chemotherapy, the complete remission rate was 60 %, the relapse rate was 47 %, and the 2-year progression-free survival rate was 37.4 %. The 2-year overall survival (OS) rate for all patients was 51.9 %. By multivariate analysis, bone marrow involvement (P < 0.001) and ECOG >1 (P = 0.007) were independent adverse factors for OS. A simplified prognostic index efficiently stratified patients into the following three groups: 2-year OS rates 79.8 % (0 factor), 28.3 % (1 factor), and 10.2 % (2 factors) by using bone marrow involvement and ECOG >1 (P < 0.001). In conclusion, AITL patients were older and had poorer prognosis in Taiwan. Bone marrow involvement, EOCG >1, IPI >1 and PIT >1 had adverse impact on OS. The usefulness of this simplified prognostic index needs further validation.

Targeting B-cell non Hodgkin lymphoma: New and old tricks

The management of B-cell malignancies continues to pose a clinical challenge. In the past years, rituximab (anti-CD20) emerged as the standard of care in the induction treatment of follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL), chronic lymphocytic leukemia (CLL), and mantle cell lymphoma (MCL), as well as in other subsets. Since the benefits of immuno-chemotherapy have been clearly demonstrated in a whole range of lymphomas, several innovative approaches are being explored to achieve significant responses, particularly in refractory B-cell non-Hodgkin lymphoma (NHL) cases. Studies of the comparative effectiveness and structure/function relationship of therapeutic monoclonal antibodies, together with an increased understanding of the molecular features of NHLs, have led to the development of a range of novel therapies, many of which target the tumor in a tailored fashion. Although several molecules can help clinicians to dissect the pathological mechanisms acting in the natural history of the disease, the main purpose of this review emphasize the recent developments in targeting the B-cell NHLs surface. These novel approaches are illustrated, and the new intriguing opportunities offered by bispecific antibodies and antibody-associated immune modulation are addressed.

Recent advances in intestinal lymphomas

A large variety of lymphoma types may develop as primary intestinal neoplasms in the small intestines or, less often, in the colorectum. Among these are a few entities such as enteropathy-associated T-cell lymphoma or immunoproliferative small intestinal disease that, essentially, do not arise elsewhere than in the gastrointestinal tract. In most instances the primary intestinal lymphomas belong to entities that also occur in lymph nodes or other mucosal sites, and may show some peculiar features. In the case of follicular lymphoma, important differences exist between the classical nodal cases and the intestinal cases, considered as a variant of the disease. It is likely that the local intestinal mucosal microenvironment is a determinant in influencing the pathobiological features of the disease. In this review we will present an update on the clinical, pathological and molecular features of the lymphoid neoplasms that most commonly involve the intestines, incorporating recent developments with respect to their pathobiology and classification. We will emphasize and discuss the major differential diagnostic problems encountered in practice, including the benign reactive or atypical lymphoid hyperplasias, indolent lymphoproliferative disorders of T or natural killer (NK) cells, and Epstein-Barr virus (EBV)-related lymphoproliferations.

Peripheral T-cell and NK cell lymphoproliferative disorders: cell of origin, clinical and pathological implications

T-cell lymphoproliferative disorders are a heterogeneous group of neoplasms with distinct clinical-biological properties. The normal cellular counterpart of these processes has been postulated based on functional and immunophenotypic analyses. However, T lymphocytes have been proven to be remarkably capable of modulating their properties, adapting their function in relationship with multiple stimuli and to the microenvironment. This impressive plasticity is determined by the equilibrium among a pool of transcription factors and by DNA chromatin regulators. It is now proven that the acquisition of specific genomic defects leads to the enforcement/activation of distinct pathways, which ultimately alter the preferential activation of defined regulators, forcing the neoplastic cells to acquire features and phenotypes distant from their original fate. Thus, dissecting the landscape of the genetic defects and their functional consequences in T-cell neoplasms is critical not only to pinpoint the origin of these tumors but also to define innovative mechanisms to re-adjust an unbalanced state to which the tumor cells have become addicted and make them vulnerable to therapies and targetable by the immune system. In our review, we briefly describe the pathological and clinical aspects of the T-cell lymphoma subtypes as well as NK-cell lymphomas and then focus on the current understanding of their pathogenesis and the implications on diagnosis and treatment.

Immunohistochemistry as a valuable tool to assess CD30 expression in peripheral T-cell lymphomas: high correlation with mRNA levels

The extended use of brentuximab-vedotin was reported for CD30(+) nonanaplastic peripheral T-cell lymphomas (PTCLs) with promising efficacy. CD30 status assessment is thus a critical factor for therapeutic decision, but the reliability of immunohistochemistry (IHC) in evaluating its expression remains to be defined. This prompted us to investigate the correlation between semiquantitative CD30 protein assessment by IHC and messenger RNA (mRNA) assessment by microarrays in a cohort of 376 noncutaneous PTCLs representative of the main entities. By IHC, CD30 expression was heterogeneous across and within entities and significantly associated with large tumor cell size. In addition to 100% anaplastic large-cell lymphomas, 57% of other PTCL entities were CD30-positive at a 5% threshold. CD30 protein expression was highly correlated to mRNA levels. mRNA levels were bimodal, separating high from low CD30-expressing PTCL cases. We conclude that IHC is a valuable tool in clinical practice to assess CD30 expression in PTCLs.

Brentuximab vedotin for treatment of systemic T-cell lymphoma

INTRODUCTION

Brentuximab vedotin (BV) is an antibody-drug conjugate that consists of the anti-CD30 monoclonal antibody conjugated with monomethyl auristatin E. BV has been approved by the US Food and Drug Administration and the European Medicines Agency for the treatment of relapsed or refractory Hodgkin lymphoma and anaplastic large cell lymphoma. These two diseases certainly show high levels of CD30 expression. Of interest, however, BV has shown activities in other lymphomas that express low or even undetectable levels of CD30.

AREAS COVERED

We update and summarize a recent report of BV in T-cell lymphomas.

EXPERT OPINION

Single-agent BV showed overall response rates of 54% in angioimmunoblastic T-cell lymphoma and 33% in peripheral T-cell lymphoma not otherwise specified in the recent trial. The efficacy of BV in T-cell lymphomas with low or undetectable CD30 expression was promising. The use of BV in combination with chemotherapy as frontline treatment is currently being investigated. Future studies should include correlative biomarker analysis and optimization of combination therapies.

Molecular genetics of peripheral T-cell lymphomas

Peripheral T-cell lymphomas (PTCL) are rare neoplasms that in most instances respond poorly to conventional chemotherapies. Four varieties--PTCL not otherwise specified (NOS), angioimmunoblastic T-cell lymphoma (AITL), ALK+ anaplastic T-cell lymphoma (ALCL), and ALK- ALCL--account for about 60 % of them. Their classification is difficult because of the wide spectrum of morphologic features and the lack of robust immunohistochemical markers. Thus, high-throughput technologies can importantly contribute to their better understanding. In particular, gene expression profiling has cleared the borders among PTCL/NOS, ALK- ALCL and AITL. In fact, gene signatures have been developed even from formalin-fixed paraffin-embedded tissue samples that definitely distinguish one tumor from the other(s). This has important practical implications: for instance on routine diagnostics PTCL/NOS expressing CD30 can be easily confused with ALK- ALCL, but has a much worse prognosis. Therefore, the clear-cut distinction between the two conditions is pivotal to understand the results of ongoing trials with Brentuximab Vedotin, targeting the CD30 molecule. Besides improving the diagnosis, molecular studies have provided the rationale for the usage of novel drugs in the setting of PTCLs, such as ALK inhibitors in ALK+ ALCL, anti-angiogenetic drugs in AITL, and tyrosine kinase inhibitors in PTCL/NOS and ALK+ and ALK- ALCLs.

Brentuximab vedotin for Hodgkin lymphoma and systemic anaplastic large cell lymphoma: a review of clinical experience and future directions

SUMMARY Brentuximab vedotin is a novel agent indicated for the treatment of relapsed and refractory Hodgkin lymphoma and systemic anaplastic large cell lymphoma. Brentuximab vedotin is an antibody–drug conjugate consisting of chimeric anti-CD30 antibody cAC10, linked to four molecules of monomethylauristatin E, a tubulin destabilizer. It was granted US FDA approval in 2011 following two pivotal Phase II studies showing objective responses of 75 and 86% in heavily pretreated relapsed and refractory Hodgkin lymphoma and systemic anaplastic large cell lymphoma, respectively. Brentuximab vedotin can be used as a bridge to more definitive stem cell transplant. There are currently over 30 open clinical studies involving the use of brentuximab vedotin used as single agent or combined with chemotherapy in both front-line and salvage settings. These studies include use in other CD30-positive B- and T-cell lymphomas, as well as in CD30-positive germ cell tumors. In clinical practice brentuximab vedotin has been associated with significant sensory and motor neuropathies and clinicians should be alert to the potential for significant neuropathy and the need for dose reduction. However, the potential for significant neuropathy must be balanced against the remarkable clinical benefit of brentuximab vedotin in patients with heavily pretreated relapsed and refractory lymphomas.