CD30+ Neoplasms of the Skin

The expression of CD30 and its clinico-pathologic significance in peripheral T-cell lymphomas

INTRODUCTION

Recent studies have shown that CD30 expression can be an important feature of peripheral and cutaneous T-cell lymphomas (PTCLs and CTCLs) and CD30 testing has increased in importance with the emergence of CD30-directed therapy.

AREAS COVERED

This article reviews the literature on CD30-related biology, prevalence, and therapy in patients with PTCL or CTCL. We searched the PubMed database from 1 January 2010 to 28 April 2020, using terms 'CD30' ('peripheral T-cell lymphomas' or 'cutaneous T-cell lymphoma') and 'immunohistochemistry' or 'flow cytometry' or 'pathology,' and synonyms including terms for T-cell lymphoma subtypes.

EXPERT OPINION

CD30 is expressed at relatively high rates of prevalence across a broad range of PTCLs and CTCLs. CD30 expression may be critical to the development of a subset of PTCLs and also a biomarker for treatment choice in some subtypes. Large-scale randomized, controlled studies have shown that CD30-directed treatment with brentuximab vedotin is significantly more effective against CD30-expressing PTCL and CTCL than current standard-of-care regimens. However, accurate CD30 evaluation is limited by inconsistencies in detection methodology and expression cutoffs defining CD30-expressing disease. Greater understanding of CD30 testing and reporting will enable more patients with CD30-expressing PTCL and CTCL to be identified and treated appropriately.

Remission of refractory granulomatous primary cutaneous anaplastic large cell lymphoma to brentuximab vedotin

Primary cutaneous anaplastic large cell lymphoma (PC-ALCL) is a rare non-Hodgkin's lymphoma that arises as a single, or multiple dome-shaped tumours on the skin. The histology is characterised by the presence of atypical lymphocytes with large irregularly shaped nuclei that express the surface marker CD30. There can be significant heterogeneity in clinical manifestation and histological pattern and in rare cases accurate diagnosis can be a challenge. Here, we present an unusual case presentation of cutaneous CD30+ anaplastic large cell lymphoma with significant granulomatous histology pattern that mimicked sarcoid. After a lack of durable response to treatments that included glucocorticoid and methotrexate, targeted treatment with anti-CD30 monoclonal antibody drug conjugate (brentuximab vedotin) yielded long-term clinical remission.

Combination of brentuximab-vedotin with skin-directed therapies extends the time to the next therapeutic line in patients with cutaneous T-cell lymphoma

BACKGROUND AND OBJECTIVES

Brentuximab vedotin (BV) is a potent therapeutic option for CD30-positive cutaneous T-cell lymphoma. Unlike existing studies, BV and other therapeutic procedures were frequently combined for our patients. In this context, the study aims to analyze the effectiveness and safety of BV in a real-world setting.

PATIENTS AND METHODS

This is a retrospective monocentric study analyzing treatment outcomes for patients with CD30-positive cutaneous T-cell lymphoma treated with BV.

RESULTS

26 patients (median age: 67 years) were included in the study. Patients were treated with 1.8 or 1.2 mg/kg b.w. Complete remission (CR) was reached in 30.8 % of the patients, and the objective response rate (ORR) was 84.6 %. Side effects were seen in 19 of the 26 patients. As a reaction to progressive disease (PD) under BV monotherapy, we included skin-directed procedures such as tumor excision, local radiotherapy, and PUVA for six patients. We re-stabilized the disease and maintained the line of therapy without additional toxicities for a median of seven months longer using this concept.

CONCLUSIONS

Addition of skin-directed therapies (SDT) after disease progression under BV monotherapy could stabilize the disease's continuous advancement or even lead to partial response, thereby extending the time until the next therapeutic escalation.

Novel therapies targeting cutaneous T cell lymphomas and their microenvironment

Cutaneous T-cell lymphomas (CTCL) are rare non-Hodgkin lymphomas with a generally indolent course managed with topical, skin-directed therapies. A small subset, however, will progress to advanced stage disease necessitating systemic therapy for disease control. Currently approved therapies have low response rates and generally short durations of response. Novel therapies, therefore, are urgently needed to address this unmet need. In this review, the mechanisms of CTCL pathogenesis and progression, including the role of the tumor microenvironment and molecular alterations, are summarized. Based on these biologic insights, novel therapies currently under investigation and those with a strong preclinical biologic rationale including T cell and macrophage checkpoint inhibitors, epigenetic regulators, targeted antibodies, tyrosine kinase inhibitors, and apoptosis modulating therapies are discussed.

Critical concepts and management recommendations for cutaneous T-cell lymphoma: A consensus-based position paper from the Italian Group of Cutaneous Lymphoma

In this paper, we present a review of critical concepts, and produce recommendations on management issues in cutaneous T-cell lymphomas (CTCLs) of adults. A panel of nine experts was selected for their expertise in research and clinical practice of CTCLs. During an initial meeting, the areas of major concern in the management of CTCLs were selected by generating and rank-ordering clinical key questions using the criterion of clinical relevance, through group discussion. Recommendations were achieved by multiple-step formalized procedures to reach a consensus after a comprehensive analysis of the scientific literature. The panel produced recommendations on how to facilitate the clinical suspicion of CTCL; indication of cutaneous biopsy; optimal histological diagnosis, immunohistochemistry and genetic markers; and staging pathway and up-to-date therapeutics (with particular focus on new treatments). The critical concept of integration of the different medical expertise in the management of the patients with CTCL was thoroughly examined. These recommendations are intended for use not only by expert centers but above all by "not experienced" dermatologists and hematologists as well as general practitioners.

Brentuximab Vedotin in the Treatment of Peripheral T Cell Lymphoma and Cutaneous T Cell Lymphoma

PURPOSE OF REVIEW

The recent development of brentuximab vedotin (BV), an antibody-drug conjugate targeting CD30-positive cells, has led to therapeutic advances in the treatment of T cell lymphomas. In this review, we discuss key studies of BV in peripheral T cell lymphoma (PTCL) and cutaneous T cell lymphoma (CTCL) and highlight important questions for further investigation.

RECENT FINDINGS

Monotherapy with BV has proven to be effective and well tolerated in patients with relapsed/refractory (R/R) CD30-positive CTCL. BV has shown significant activity in R/R PTCL as well, with particularly durable responses in patients with anaplastic large cell lymphoma (ALCL). In a landmark phase III study (ECHELON-2), BV + CHP demonstrated superior progression-free and overall survival relative to CHOP as frontline therapy for patients with CD30-expressing PTCL, representing the first randomized trial demonstrating an overall survival benefit in PTCL. Though BV is overall well tolerated, peripheral neuropathy remains a clinically significant adverse effect. BV is a major therapeutic advance in the treatment of patients with R/R CTCL and of those with PTCL in both the R/R and frontline settings. Key ongoing areas of investigation include optimization of CD30 expression as a predictive biomarker as well as the role of BV in consolidation therapy.

A Systematic Approach to the Cutaneous Lymphoid Infiltrates: A Clinical, Morphologic, and Immunophenotypic Evaluation

CONTEXT.—

The evaluation of cutaneous lymphoid infiltrates, both neoplastic and inflammatory, occurs very frequently in routine dermatopathologic examination and consultation practices. The "tough" cutaneous lymphoid infiltrate is feared by many pathologists; skin biopsies are relatively small, whereas diagnostic possibilities are relatively broad. It is true that cutaneous lymphomas can be difficult to diagnose and that in many circumstances multiple biopsies are required to establish a correct diagnostic interpretation. As a reminder, one should understand that low-grade cutaneous lymphomas are indolent disorders that usually linger for decades and that therapy does not result in disease cure. It is also important to remember that in most circumstances, those patients will die from another process that is completely unrelated to a diagnosis of skin lymphoma (even in the absence of specific therapy).

OBJECTIVE.—

To use a clinicopathologic, immunophenotypic, and molecular approach in the evaluation of common lymphocytic infiltrates.

DATA SOURCES.—

An in-depth analysis of updated literature in the field of cutaneous lymphomas was done, with particular emphasis on updated terminology from the most recent World Health Organization classification of skin and hematologic tumors.

CONCLUSIONS.—

A diagnosis of cutaneous lymphoid infiltrates can be adequately approached using a systematic scheme following the proposed ABCDE system. Overall, cutaneous T- and B-cell lymphomas are rare and "reactive" infiltrates are more common. Evaluation of lymphoid proliferations should start with a good sense of knowledge of the clinical presentation of the lesions, the clinical differential considerations, and a conscientious and appropriate use of immunohistochemistry and molecular tools.

Antibody-Directed Therapies: Toward a Durable and Tolerable Treatment Platform for CTCL

Cutaneous T-cell lymphomas (CTCL) are a rare group of heterogeneous disorders characterized by cutaneous involvement of monoclonal T-lymphocytes. Although indolent at early stages, CTCL can confer significant morbidity, and mortality when advanced. There is an unmet need for tolerable and durable treatments with antibodies recently gaining promise. Here we review approved systemic therapies and discuss select antibodies in development.

Brentuximab Vedotin for Patients With Refractory Lymphomatoid Papulosis: An Analysis of Phase 2 Results

Importance

Brentuximab vedotin is a monomethyl auristatin E-conjugated monoclonal antibody directed against CD30. It represents a potential treatment for the CD30+ lymphoproliferative disorder lymphomatoid papulosis (LyP), which currently has no approved treatment.

Objective

To assess the efficacy and safety of brentuximab vedotin for the treatment of LyP.

Design, Setting, and Participants

In this study conducted at The University of Texas MD Anderson Cancer Center from May 10, 2011, to March 31, 2017, a total of 12 patients with LyP received brentuximab vedotin. All patients were 18 years or older with a diagnosis of LyP and were also required to have scarring, more than 10 lesions, or active lesions on the face, hands, or feet. Nine patients were enrolled in a physician-initiated, open-label, single-center, phase 2 clinical trial of brentuximab vedotin for CD30+ cutaneous T-cell lymphomas and LyP from 2011 to 2013. Three patients were later treated outside of the trial from 2013 to 2017. Five patients continued to be followed up as of March 2017.

Interventions

Intravenous brentuximab vedotin 1.8 mg/kg infused over 30 minutes every 21 days.

Main Outcomes and Measures

The primary end point was the overall response rate. Complete response was defined as zero lesions, and partial response was defined as a 50% or greater reduction in lesion count from baseline. A relapse was defined as loss of partial response.

Results

All 12 patients (8 men and 4 women; median age, 46 years) responded to brentuximab vedotin, and 7 exhibited a complete response. Time to response was 3 weeks in all patients. The median duration of response was 20 weeks (range, 6-103 weeks). For 5 patients who relapsed, the median time to relapse was 12 weeks (range, 6-41 weeks). One patient who relapsed was retreated and has remained in partial response for more than 23 months. Grade 1 to 2 neuropathy occurred in 10 patients but resolved in 5. Adverse events of grade 3 or higher were neutropenia (n = 2) and dizziness/vertigo (n = 1). Three patients withdrew owing to adverse events.

Conclusions and Relevance

Brentuximab vedotin is effective in treating LyP (overall response rate, 100%; complete response rate, 58%), but its use should be reserved for patients with truly severe and refractory LyP. More work is needed to optimize its dosing to minimize adverse events, such as peripheral neuropathy.

Trial Registration

clinicaltrials.gov Identifier: NCT01352520.

Cutaneous T-cell lymphomas: Focusing on novel agents in relapsed and refractory disease

Patients with relapsed or refractory cutaneous T-cell lymphoma (CTCL) display a dismal prognosis and their therapy represents an unmet medical need, as the best treatment strategy is yet to be determined. Exciting data on novel targeted agents are now emerging from recently concluded and ongoing clinical trials in patients with relapsed and refractory CTCL. Three FDA approved compounds are used as single agents including the oral retinoid bexarotene and histone deacetylase inhibitors romidepsin and vorinostat. Brentuximab vedotin, an anti-CD30 drug-conjugated monoclonal antibody, has received from European Commission the orphan designation but has not been approved by EMA yet. Several other molecules have demonstrated their activity in the same context and combination strategies are being explored. Participation in a well designed clinical trial is encouraged, as the introduction of novel agents will continue to expand the therapeutics options available in the management of CTCL.

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.

A new era for cutaneous CD30-positive T-cell lymphoproliferative disorders

Cutaneous CD30+ T-cell lymphoproliferative disorders (CD30+ T-LPD) represent a spectrum encompassing lymphomatoid papulosis (LyP), primary cutaneous anaplastic large-cell lymphoma (pcALCL) and borderline lesions. They share the expression of CD30 as a common phenotypic marker. They differ however in their clinical presentation, the histological features and clinical course. Moreover, LyP and PcALCL show numerous clinical, histological and phenotypic variants. Overlapping features of LyP and pcALCL with themselves and with other cutaneous and systemic lymphomas emphasize the importance of careful clinicopathologic correlation and staging in the diagnosis of CD30+ T-LPD. Furthermore, an increasing number of inflammatory and infectious skin disorders harboring medium-sized to large CD30+ cells have to be considered in the differential diagnosis. Whereas the expression of CD30 in cutaneous CD30+ T-LPD stands for a favourable prognosis, its expression in other cutaneous and systemic lymphomas has a divergent impact. The assessment of CD30 expression does not only provide prognostic information, but is of potential therapeutic relevance as CD30 can serve as a therapeutic target. This review focuses on the clinicopathological and phenotypic spectrum of CD30+ T-LPD, its differential diagnoses and the role of CD30 as a diagnostic, prognostic and therapeutic marker.

Lymphomatoid Papulosis in Children and Adolescents: A Systematic Review

BACKGROUND

Lymphomatoid papulosis (LyP) is a lymphoproliferative disorder that is rare among adults and even rarer among children. In adults, LyP is associated with an increased risk of secondary lymphomas.

OBJECTIVE

The aim of this systematic review was to describe the clinical and histopathological features of LyP in children, to assess the risk of associated lymphomas, and to compare the disease to the adult form.

METHODS

A systematic review was conducted using the MEDLINE (PubMed), EMBASE, Scopus, and Cochrane databases from inception to June 2015. Articles were included if data were extractable from studies, case series, and single reports of pediatric LyP patients.

RESULTS

A total of 251 children and adolescents with LyP were identified, with the mean age at diagnosis being 9.3 ± 4.6 years (n = 187). The female to male ratio was 1:1.4, and the majority of children reported on were Caucasian (n = 74, 85.1 %). The predominant histologic subtype was type A (n = 106, 79.1 %). Clinically, LyP lesions presented as erythematous papules or nodules, appearing preferentially on the extremities and the trunk. LyP has to be differentiated from pityriasis lichenoides (PL) and primary cutaneous anaplastic large cell lymphoma (ALCL). PL and associated lymphomas were diagnosed before, with, and after LyP in 19 and 14 cases, respectively. Of the 14 subjects with associated lymphomas, two children developed systemic ALCL.

CONCLUSION

LyP has to be differentiated from ALCL to avoid erroneous treatments. Due to the increased risk of development of non-Hodgkin lymphomas, lifelong follow-up and proper patient counseling are warranted.

CD30 As a Target for the Treatment of Cutaneous T-Cell Lymphoma

A 72-year-man presented with a 7-month history of progressive patches and plaques over the trunk and limbs. A skin biopsy confirmed mycosis fungoides (MF). After staging investigations, he was considered to have T2N0M0B0 (stage Ib) disease and began ultraviolet (UV) B phototherapy. Despite initial response, his disease progressed after 4 months, with enlarging patches and plaques but without nodal involvement. As second-line therapy, he received interferon alfa-2b (IFN--2b) 2.7 MU daily, which he tolerated well. He again experienced initial partial response (PR), but by 18 months, he had experienced tumor progression, with patches, plaques, and multiple tumors over the body (up to 3 cm; Fig 1). Biopsy of a neck tumor demonstrated tumor-stage MF,with no evidence of large-cell transformation. Approximately 30% of lymphocytes strongly expressed CD30. CD25 was negative. He began treatment with oral methotrexate 20mg per week, which he tolerated well, and achieved a PR lasting 7 months before multiple plaque and tumor lesions recurred, along with the development of inguinal lymphadenopthy. Biopsy of the skin lesions confirmed the same disease, and [18F]fluorodeoxyglucose–positron emission tomography demonstrated avidity in inguinal and internal iliac nodes, with lymphadenopathy measuring up to 3.5 cm. He has been referred for consideration of further systemic therapy.

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.

Results of a Phase II Trial of Brentuximab Vedotin for CD30+ Cutaneous T-Cell Lymphoma and Lymphomatoid Papulosis

PURPOSE

Brentuximab vedotin, a monoclonal antibody (cAC10) conjugated to monomethyl auristatin E, targets CD30(+) receptors. This phase II open-label trial was conducted to evaluate safety and efficacy in CD30(+) cutaneous T-cell lymphomas.

PATIENTS AND METHODS

Forty-eight patients with CD30(+) lymphoproliferative disorders or mycosis fungoides (MF) received an infusion of 1.8 mg/kg every 21 days.

RESULTS

Forty-eight evaluable patients (22 women and 26 men; median age, 59.5 years) had an overall response rate of 73% (95% CI, 60% to 86%; 35 of 48 patients) and complete response rate of 35% (95% CI, 22% to 49%; 17 of 48 patients). Fifteen (54%; 95% CI, 31% to 59%) of 28 patients with MF responded, independent of CD30 expression. In patients with MF/Sézary syndrome, the overall response rate was 50% (five of 10 patients) in patients with low CD30 expression (< 10%), 58% (seven of 12 patients) in patients with medium expression (10% to 50%), and 50% (three of six patients) in patients with high expression (≥ 50%). Time to response was 12 weeks (range, 3 to 39 weeks), and duration of response was 32 weeks (range, 3 to 93 weeks). All patients with lymphomatoid papulosis (n = 9) and primary cutaneous anaplastic T-cell lymphomas (n = 2) responded; time to response was 3 weeks (range, 3 to 9 weeks), and median duration of response was 26 weeks (range, 6 to 44 weeks). Soluble baseline CD30 levels were lowest in complete responders (P = .036). Grade 1 to 2 peripheral neuropathy was observed in 65% of patients (95% CI, 52% to 79%; 31 of 48 patients), is still ongoing in 55% of patients (95% CI, 41% to 69%; 17 of 31 patients), and resolved in 45% of patients (95% CI, 31% to 59%; 14 of 31 patients), with a median time to resolution of 41.5 weeks. Grade 3 to 4 events were neutropenia (n = 5), nausea (n = 2), chest pain (n = 2), deep vein thrombosis (n = 1), transaminitis (n = 1), and dehydration (n = 1). Dose reductions to 1.2 mg/kg were instituted as a result of grade 2 neuropathy (n = 6), transaminitis (n = 1), and arthralgias and fatigue (n = 2).

CONCLUSION

Brentuximab vedotin is both active and well tolerated in cutaneous T-cell lymphoma and lymphomatoid papulosis, with an overall response rate of 73% and complete response rate of 35%.

Lymphomatoid papulosis: A cutaneous lymphoproliferative disorder in a patient on fingolimod for multiple sclerosis

BACKGROUND

Fingolimod was the first oral disease-modifying treatment for relapsing-remitting multiple sclerosis. It has previously been associated with the development of lymphoma.

OBJECTIVE

To describe a case of lymphomatoid papulosis, a CD30+ cutaneous lymphoproliferative disorder, in a patient taking fingolimod.

METHODS

Case study.

RESULTS

Our patient developed lymphomatoid papulosis 2 months after starting fingolimod. Histology confirmed the diagnosis. The drug was withdrawn. Resolution began only 2 days later.

CONCLUSIONS

Lymphomatoid papulosis is a benign subtype of cutaneous T-cell lymphoma, but up to 20% of cases can transform to a malignant course. Patients on fingolimod and physicians caring for them should be mindful of the need to monitor the skin.

CD30 as a therapeutic target for lymphoma

Hodgkin's lymphoma (HL) and ALK(+) anaplastic large-cell lymphoma (ALCL) have become highly curable due to the success of modern regimens of chemotherapy and radiotherapy. However, up to one-third of the patients experience relapse or do not respond to first-line therapy, and half of them relapse again after secondary therapy with limited options for further treatment. In the last 15 years, monoclonal antibodies (mAbs) directed to surface receptors became a new and valuable therapeutic option in many hematologic malignancies. Due to its restricted expression on normal activated lymphocytes and its high expression on malignant cells, CD30 represents an attractive target molecule for HL and ALCL therapy. However, unconjugated CD30 mAbs have demonstrated a lack of objective clinical responses in patients with recurrent HL. CD30 exhibits complex signaling pathways, and binding of its natural ligand or anti-CD30 mAbs can induce apoptosis but may also promote proliferation and activation depending on the cellular context. Moreover, CD30 rapidly internalizes after crosslinking, which counteracts efficient recruitment of immunologic effectors but also provides the opportunity to transfer cytotoxic payloads coupled to CD30-specific mAbs into the tumor cells. Several tumor targeting approaches have been studied, including radio-immunoconjugates, immunotoxins, immunoRNases, immunokinases, and antibody drug conjugates (ADCs). In 2011, the ADC brentuximab-vedotin, consisting of the CD30-specific chimeric mAb cAC10 and the potent tubulin toxin monomethyl auristatin E, gained regulatory approval as a well tolerated and highly active drug in patients with refractory and relapsed HL and ALCL. SGN-35 is on the way to being incorporated in the standard management of CD30(+) lymphoma with significant therapeutic impact. This review gives a critical overview about anti-CD30 therapies with unconjugated, engineered, and conjugated mAbs and the therapeutic challenges of treatment of CD30(+) lymphoma.

Contribution of longitudinal follow up and clinical pathological correlation in the diagnosis CD30-positive skin infiltrates

The diagnosis of a CD30+ cutaneous infiltrate is often difficult and requires clinicopathologic correlation. To further evaluate this challenge, initial clinical and histopathologic diagnoses were correlated with final clinicopathologic diagnosis in 44 cases with CD30 immunopositivity. Dermatopathologic evaluation confirmed the initial clinical diagnosis in 65% of the suspected benign cases, all cases of suspected lymphomatoid papulosis (LyP), and 72% of clinically malignant cases. In the 25 patients with clinical suspicion for lymphoma, the histopathologic diagnoses included lymphoma in 18, LyP in 2, CD30+ lymphoproliferative disorder (CD30 LPD) in 3 and hypersensitivity reaction in 2 patients. Clinicopathologic correlation led to a change in three cases diagnosed histopathologically as anaplastic large cell lymphoma (ALCL) reclassified as LyP type C, and one patient diagnosed as CD30 LPD clinically evolved as herpes virus infection. Furthermore, five cases reported as CD30 LPD received more specific diagnoses after clinicopathologic correlation (LyP type C in three, and ALCL in two patients). Clinicopathologic correlation is essential in establishing the correct diagnosis of CD30 LPD, in particular the distinction of ALCL from LyP type C. In this setting, the histopathologic diagnosis of CD30 LPD is advisable in the absence of clinical data.

Cutaneous CD30-Positive Lymphoproliferative Disorders

Cutaneous CD30+ lymphoproliferative disorders are the second most common types of cutaneous T-cell lymphomas. They represent a well-defined spectrum encompassing lymphomatoid papulosis (LyP), primary cutaneous anaplastic large-cell lymphoma (pcALCL), and borderline lesions. They share the expression of CD30 as a common phenotypic hallmark, but they differ in their clinical presentation, course, and histologic features. New variants have been recently identified, including CD8+ epidermotropic LyP type D, angioinvasive LyP type E, and ALK-positive pcALCL. This review describes clinical, histopathologic, and phenotypic variants; their differential diagnoses (benign and malignant); and the role of CD30 as a diagnostic, prognostic, and therapeutic marker.

Targeting CD30 in malignant tissues: challenges in detection and clinical applications

The CD30 transmembrane receptor from the tumor necrosis factor receptor family is expressed in a distinct, yet diverse set of lymphoproliferative disorders and a small subset of normal activated lymphocytes. Therefore, detection of CD30 expression when performed properly according to the standardized methods facilitates diagnosis of Hodgkin lymphoma, anaplastic large cell lymphoma, and other disorders expressing the receptor. More recently, CD30 has also become an attractive therapeutic target. The preliminary observations indicate that the methods currently used to detect CD30 expression, typically immunohistochemistry performed on formalin-fixed, paraffin-embedded tissues, may be suboptimal in regard to identifying CD30 as a therapeutic target since only a limited number of CD30 receptor molecules per cell may be sufficient to achieve therapeutic effect.

Mimics of cutaneous lymphoma: report of the 2011 Society for Hematopathology/European Association for Haematopathology workshop

The Society for Hematopathology and European Association for Haematopathology workshop, from October 27 to 29, 2011, in Los Angeles, CA, exhibited many exemplary skin biopsy specimens with interesting inflammatory changes mimicking features of cutaneous lymphoma. This article reviews features observed in cutaneous lymphoid hyperplasia, cutaneous drug reactions, lupus-associated panniculitis, pityriasis lichenoides, hypereosinophilic syndrome, histiocytic necrotizing lymphadenitis, traumatic ulcerative granuloma with stromal eosinophils, and pigmented purpuric dermatosis, as well as a brief review of the pertinent literature and discussion of submitted conference cases. For the pathologist, it is important to be aware of diagnostic pitfalls as well as the limitations of ancillary testing (eg, clonality studies). Finally, correlation with total clinical information, good communication with clinical colleagues, close clinical follow-up with rebiopsy, and prudent use of laboratory studies are vital and will likely offer the best path toward a correct diagnosis.