How I Diagnose Anaplastic Large Cell Lymphoma.

OBJECTIVES: This review describes our approach to the diagnosis of all 4 anaplastic large cell lymphoma (ALCL) entities. METHODS: ALCLs are a group of CD30-positive mature T-cell lymphomas with similar morphologic and phenotypic characteristics but variable clinical and genetic features. They include systemic ALK-positive ALCL, systemic ALK-negative ALCL, primary cutaneous ALCL, and the recently described provisional entity breast implant-associated ALCL. RESULTS: In cases with classic features, the diagnosis of ALCL is often straightforward. However, variant histology, the importance of clinical history, and multiple antigenic aberrancies all present challenges to accurate diagnosis and subclassification. CONCLUSIONS: A systematic approach to the diagnosis of ALCL and awareness of potential mimics are critical to avoid misdiagnosis. It is also crucial to correctly identify localized forms of ALCL to avoid classification as systemic ALCL and subsequent overtreatment.

Is Breast Implant-Associated Anaplastic Large Cell Lymphoma Better Classified as a Lymphoproliferative Disorder and How Surgeons Reduce Risk?

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a complex topic with evolving classification and etiology. Commonalities between BIA-ALCL and lymphoproliferative disorders exist, suggesting that BIA-ALCL may be better represented on a spectrum of disease from benign effusion to malignant metastatic lymphoma. Meticulous sterile surgical technique, involving the use of betadine-containing irrigation, should be used to decrease the biological burden introduced into the surgical field and possibly prevent future incidences of BIA-ALCL.

Hematolymphoid Neoplasms Rarely Mimic Undifferentiated Pleomorphic Sarcoma of Soft Tissue.

CONTEXT.­: Undifferentiated pleomorphic sarcoma (UPS) of soft tissue is defined as a sarcoma with no recognizable line of differentiation. During the past few decades, advances in ancillary studies and review of prior UPS diagnoses have narrowed the category of UPS by excluding more-specific malignancies. However, few of those studies have specifically targeted pleomorphic hematolymphoid neoplasms. OBJECTIVE.­: To determine what fraction of UPS cases are misclassified pleomorphic hematolymphoid neoplasms, such as anaplastic large cell lymphoma, diffuse large B-cell lymphoma, histiocytic sarcoma (HS), myeloid sarcoma, and follicular dendritic cell sarcoma. DESIGN.­: Sixty-one UPS cases were screened by tissue microarray and an immunostain panel with subsequent analysis on whole block sections for suspicious cases. RESULTS.­: Five of 61 tumors (8%) were suggestive of HS based on the screening panel and were further evaluated with additional immunostains (PU.1, CD45, CD163) using whole sections. The 5 candidate HS cases were only focally positive for at most one stain with most staining in smaller, less-pleomorphic cells. Ultimately, no UPS met criteria for anaplastic large cell lymphoma, diffuse large B-cell lymphoma, myeloid sarcoma, follicular dendritic cell sarcoma, or HS. CONCLUSIONS.­: Our results suggest that a UPS of somatic soft tissue is unlikely to represent a misclassified hematopoietic malignancy. Exclusion of HS is most challenging, but immunostaining for PU.1, a nuclear transcription factor, may be easier to interpret in this context.

Genetic Subtypes of Systemic Anaplastic Large Cell Lymphoma Show Distinct Differences in PD-L1 Expression and Regulatory and Cytotoxic T Cells in the Tumor Microenvironment.

Anaplastic large cell lymphomas (ALCL) encompass several subgroups that differ in their clinical presentation, genetic features, and prognosis. We characterized the genetic subgroups of 74 patients with ALCL and correlated programmed death ligand 1 (PD-L1) protein expression and compared the densities and ratios of FOXP3+ T regulatory cells and CD8+ tumor-infiltrating lymphocytes (TILs) in tumor cells and the immune microenvironment. The subgroups included anaplastic lymphoma kinase (ALK)-positive (ALK+) ALCL and ALK-negative (ALK-) ALCL and DUSP22-rearranged and nonrearranged ALK- ALCL. None of our cases represented the TP63-rearrangement ALK- ALCL subgroup. Our results showed that ALK+ ALCL had a higher expression of PD-L1 in the tumor cells, in contrast to ALK- ALCL, which expressed high PD-L1 in tumor-associated macrophages (TAMs). DUSP22-rearranged ALK- ALCL lacked PD-L1 expression in the tumor cells and instead expressed PD-L1 only in TAMs. There was a significant positive correlation of PD-L1 expression between tumor and TAMs in ALK+ ALCL with a negative correlation in ALK- ALCL. Systemic ALCL subgroups had similar densities of CD8+ tumor-infiltrating lymphocytes and FOXP3 T regulatory cells, but differences were observed in the ratio of CD8/FOXP3. Our results suggest that alterations in tumor microenvironment and immune responses exist among systemic ALCL subgroups and these features may account for different clinical behavior and prognosis.

Identification of a new subclass of ALK-negative ALCL expressing aberrant levels of ERBB4 transcripts.

Anaplastic large-cell lymphoma (ALCL) is a clinical and biological heterogeneous disease that includes systemic anaplastic lymphoma kinase (ALK)-positive and ALK-negative entities. To discover biomarkers and/or genes involved in ALK-negative ALCL pathogenesis, we applied the cancer outlier profile analysis algorithm to a gene expression profiling data set including 249 cases of T-cell non-Hodgkin lymphoma and normal T cells. Ectopic coexpression of ERBB4 and COL29A1 genes was detected in 24% of ALK-negative ALCL patients. RNA sequencing and 5' RNA ligase-mediated rapid amplification of complementary DNA ends identified 2 novel ERBB4-truncated transcripts displaying intronic transcription start sites. By luciferase assays, we defined that the expression of ERBB4-aberrant transcripts is promoted by endogenous intronic long terminal repeats. ERBB4 expression was confirmed at the protein level by western blot analysis and immunohistochemistry. Lastly, we demonstrated that ERBB4-truncated forms show oncogenic potentials and that ERBB4 pharmacologic inhibition partially controls ALCL cell growth and disease progression in an ERBB4-positive patient-derived tumorgraft model. In conclusion, we identified a new subclass of ALK-negative ALCL characterized by aberrant expression of ERBB4-truncated transcripts carrying intronic 5' untranslated regions.

Silicone implants and lymphoma: The role of inflammation.

The risk of hematological malignancies is mainly determined by genetic background, age, sex, race and ethnicity, geographic location, exposure to certain chemicals and radiation; along with the more recently proposed immune factors such as chronic inflammation, immunodeficiencies, autoimmunity, and infections. Paradigmatic examples include the development of lymphoma in Sjögren's syndrome and Hashimoto thyroiditis, gastric MALT lymphoma in Helicobacter pylori infection, or lymphomas associated with infections by Epstein-Barr virus, human herpes virus 8 (HHV 8) and leukemia/lymphoma virus 1 (HTLV-1). A growing number of reports indicates an increased risk of lymphoma, particularly of the anaplastic large cell (ALCL) type. The implants, specifically those used in the past, elicit chronic stimulation of the immune system against the prosthetic material. This is particularly the case in genetically susceptible hosts. We suggest that polyclonal activation may result in monoclonality in those at risk hosts, ultimately leading to lymphoma. We suggest that patients with an inflammatory response against silicone implants be monitored carefully.

A novel immunohistochemical classifier to distinguish Hodgkin lymphoma from ALK anaplastic large cell lymphoma.

Classical Hodgkin lymphoma and ALK(-) anaplastic large cell lymphoma share many features like strong CD30 expression and usually loss of B- and T-cell markers. However, their clinical course is dramatically different with curability rates of >90% for classical Hodgkin lymphoma and an unfavorable prognosis for anaplastic large cell lymphoma. Classical Hodgkin lymphoma and ALK(-) anaplastic large cell lymphoma can usually be distinguished by PAX5 expression in the Hodgkin and Reed-Sternberg cells of classical Hodgkin lymphoma and expression of cytotoxic molecules in tumor cells of anaplastic large cell lymphoma. However, in some cases the differential diagnosis is difficult owing to absence of established markers. To be able to better classify these cases, we reevaluated gene expression data of microdissected tumor cells of both lymphomas for differentially expressed genes. A classifier was established, comprising four genes strongly expressed in Hodgkin and Reed-Sternberg cells of classical Hodgkin lymphoma (MDC/CCL22, CD83, STAT3, and TUBB2B). Applying this classifier to a test cohort, Hodgkin lymphoma was successfully distinguished from ALK(-) anaplastic large cell lymphoma with an accuracy of 97% (43/44). MDC/CCL22, CD83, and STAT3 have also been found to be expressed in antigen-presenting cells. Therefore, based on our established classifier, Hodgkin and Reed-Sternberg cells differ from tumor cells of anaplastic large cell lymphoma, which can successfully be applied for practical purposes in histopathologic diagnostics.

Use of minimal disseminated disease and immunity to NPM-ALK antigen to stratify ALK-positive ALCL patients with different prognosis.

We studied the prognostic value of minimal disseminated disease (MDD) and anti-ALK immune response in children with NPM-ALK-positive anaplastic-large cell lymphoma (ALCL) and evaluated their potential for risk stratification. NPM-ALK transcripts were analyzed by RT-PCR in bone marrow/peripheral blood of 128 ALCL patients at diagnosis, whereas ALK antibody titers in plasma were assessed using an immunocytochemical approach. MDD was positive in 59% of patients and 96% showed an anti-ALK response. Using MDD and antibody titer results, patients could be divided into three biological risk groups (bRG) with different prognosis: high risk (bHR): MDD-positive and antibody titer ≤ 1/750, 26/128 (20%); low risk (bLR): MDD negative and antibody titer >1/750, 40/128 (31%); intermediate risk (bIR): all remaining patients, 62/128 (48%). Progression-free survival was 28% (s.e., 9%), 68% (s.e., 6%) and 93% (s.e., 4%) for bHR, bIR and bLR, respectively (P<0.0001). Survival was 71% (s.e., 9%), 83% (s.e., 5%) and 98% (s.e., 2%) for bHR, bIR and bLR (P=0.02). Only bHR and histology other than common type were predictive of higher risk of failure (hazard ratio 4.9 and 2.7, respectively) in multivariate analysis. Stratification of ALCL patients based on MDD and anti-ALK titer should be considered in future ALCL trials to optimize treatment.

Paediatric lymphoma in China: a clinicopathological study of 213 cases.

AIM: This retrospective study was conducted to evaluate information on paediatric lymphoma in China. METHODS: We reviewed the pathological files of patients less than 12 years of age with lymphoma in Shanghai Xinhua Hospital from January 1982 to June 2009. SPSS version 11.0 was used to analyse the results. RESULTS: Of the 213 subjects, 176 (82.6%) had non-Hodgkin's lymphoma (NHL) and 37 (17.4%) had Hodgkin's lymphoma (HL). All NHL cases had diffuse and high grade tumours, and 33.5% of these tumours primarily involved extra-nodal sites. Of the NHL cases, 56.6%, 43.3%, and 1.7% were derived from T, B, and null cells, respectively. Lymphoblastic lymphoma (LL, 50.6%), Burkitt's lymphoma (BL, 28.4%), and anaplastic large cell lymphoma (ALCL, 12.5%) comprised the majority of the NHL cases. A significant difference was found in the frequency of stage I/II cases between LL and ALCL. Paediatric HL resembled the disease in adults. CONCLUSIONS: Paediatric lymphoma in China is different from that in Western countries with respect to the incidence rate of HL and BL. The distribution pattern of NHL histological subtypes is more similar to that in Japan than that in Pakistan. These features suggest ethnic or geographic variations.

Should patients with aggressive peripheral T-cell lymphoma all be treated the same?: no... well yes, ...but maybe not for long.

The peripheral T-cell lymphomas represent about 15% to 20% of non-Hodgkin lymphomas and are marked by clinical and pathologic heterogeneity. The most common T-cell entities include peripheral T-cell lymphoma, not otherwise specified, angioimmunoblastic T-cell lymphoma, and anaplastic large cell lymphoma anaplastic lymphoma kinase-negative, which account for approximately 60% of T-cell lymphoma cases. Because of the rarity of T-cell lymphomas and lack of randomized prospective studies, treatment for these diseases is not well defined. Current treatment strategies draw from data from phase II studies, retrospective analyses, and personal experience. For fit patients who can tolerate treatment with curative intent, we treat peripheral T-cell lymphoma, not otherwise specified, angioimmunoblastic T-cell lymphoma, and anaplastic large cell lymphoma anaplastic lymphoma kinase-negative similarly with CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)-based induction therapy followed by consolidation with autologous stem cell transplant. Given the marked differences in histology, biology, and clinical presentation for these diseases, it is likely that they should be approached differently. Furthermore, prognostic factors and degree of chemosensitivity as measured by FDG-PET (fluorodeoxyglucose positron emission tomography) should likely be used to guide patients along different treatment pathways. We have a long way to go toward perfecting the treatment for T-cell lymphoma. We believe that a uniform treatment approach for patients with aggressive T-cell lymphoma is not appropriate; however, we do not yet have enough data to support an individualized approach to treatment. Clinical and biologic prognostic factors, degree of chemosensitivity as measured by FDG-PET, and histology should all likely have a role in directing patients along different treatment pathways, but prospective studies are needed to confirm this.

Anaplastic large-cell lymphoma.

The concept of anaplastic large-cell lymphoma (ALCL) has changed over the years because of a stream of new information and novel understanding regarding the cell of origin, biology, genetics, and clinical features of these neoplasms. This new information has led to the current classification proposed by the expert reviewers of the World Health Organization. The objective of this review is to present the most updated information on the cytologic and histologic features of these entities, with a special reference to diagnostic algorithms. A detailed description of the genetic aberrations and the pathogenetic mechanisms leading to transformation is presented. The clinical features of ALCL and novel tailored strategies are briefly illustrated.

[New concept for ALK negative anaplastic large cell lymphoma].

ALK negative anaplastic large cell lymphoma (ALK(-) ALCL) lacks the specific expression of ALK protein, although it also strongly expresses CD30 and resembles the morphologic characteristics of ALK positive anaplastic large cell lymphoma (ALK(+) ALCL). Recently, some new researches indicate that there exist molecular and genetic differences between these two types of ALCL. Moreover, the treatment response, prognosis, and long-term survival of ALK(-) ALCL are far worse than that of ALK(+) ALCL, such as ALK(-) ALCL is associated with older age persons, B group syndrome, disease advanced stage, high International Prognostic Index (IPI) and poor prognosis (< 49% 5-year survival). As a consequence, some new advances on basis (cell morphology and tissue pathology, immunophenotypes, cell genetics and molecular marker), diagnosis and treatment of ALK(-) ALCL are summarized in this review.

CD8-positive primary cutaneous anaplastic large T-cell lymphoma (PCALCL): case report and review of this unusual variant of PCALCL.

Primary cutaneous anaplastic large T-cell lymphoma (PCALCL) is a well-defined CD30-positive lymphoproliferative disorder with relatively good prognosis and response to treatment. We describe a case of PCALCL expressing CD8. The patient is a 57-year-old man that clinically presented with an ulcerated nodule in his left middle finger. Histopathologic sections showed an ulcerated epidermis with a diffuse lymphocytic infiltrate in the superficial dermis with focal epidermotropism. The large cohesive atypical cells were admixed with a reactive infiltrate composed of neutrophils, eosinophils, and small lymphocytes. Immunohistochemical studies showed the tumor cells to be strongly positive for CD8, CD30, and TIA-1, focally positive for CD3, and negative for CD4, CD20, CD56, Anaplastic Lymphoma Kinase (ALK-1), and HSV. Epstein-Barr virus by in situ hybridization was negative. The diagnosis of a CD8+ PCALCL was confirmed. There is limited precedent literature regarding CD8-positive PCALCL and this case falls within the clinical and histopathologic spectrum of CD30+ lymphoproliferative disorders. CD8/CD30 coexpression is rare in PCALCL and may have important clinical and prognostic implications. To the best of our knowledge there are only 4 previously reported cases describing similar findings.

Functional classification of peripheral T-cell lymphomas as an approach to improve outcome prediction and therapy selection.

Many types of peripheral T-cell lymphoma (PTCL) are currently classified by the World Health Organization (WHO) based on their predominant site of organ involvement (eg, intestinal or cutaneous types). However, this approach and traditional staging scores such as the IPI can provide limited prognostic information, especially in those PTCL types where morbidity and mortality are primarily related to immune dysregulation and cytokine syndromes driven by the lymphoma cells. These "immune participatory" PTCLs (including, commonly, angioimmunoblastic T-cell lymphoma and many extranodal types) can therefore have poor outcomes even at low tumor burdens. For these reasons, a classification that includes functional profiling of the lymphoma cells may add valuable prognostic information. Such data, including cytokine expression patterns and T-cell receptor signaling pathway activation status, whether normal or abnormal, need to be considered in future classification systems, especially when incorpating targeted therapy.

Morphological variability of lymphohistiocytic variant of anaplastic large cell lymphoma (former lymphohistiocytic lymphoma according to the Kiel classification).

According to the WHO classification, anaplastic large cell lymphoma (ALCL) is a distinct T-cell lymphoma entity with a number of morphological variants. The characteristic feature of lymphohistiocytic variant of ALCL according to the WHO classification is the abundance of histiocytes that exceed and mask the tumour cell population. In the current, study we reanalysed a historical series of 17 lymphomas, diagnosed as lymphohistiocytic lymphoma according to the criteria of the Kiel classification, with the presence of large purple macrophages (LPM) as the decisive finding for diagnosing this lymphoma subtype. We assessed the cellular composition of the tumour and correlated the results with the definition of lymphohistiocytic variant of ALCL given in the WHO classification. Although all cases in our cohort matched the criteria of ALCL according to the WHO, in 30% of the cases, the total amount of macrophages did not exceed the number of CD30-positive tumour cells. Our results indicate that the presence of LPM might be helpful to identify this subgroup of ALCL. Because the distinction of morphological subtypes of ALCL is of clinical relevance, improved criteria for subtyping ALCL are urgently needed that might include the presence LPM as one criteria.

[Clinical course and therapy of lymphomatoid papulosis. Experience with 17 cases and literature review]. / Klinische Verlaufsformen und Therapie der lymphomatoiden Papulose. Beobachtungen an 17 Fällen mit Literaturübersicht.

Lymphomatoid papulosis is a rare disease with a worldwide incidence of 1.2 to 1.9 per 1 million. It affects all age groups with a peak incidence between 30 and 40 years and an apparent male predominance. Occurrence in childhood has also been described. Both the etiology and pathogenesis of the disease are unknown. The clinical presentation is extremely variable and frequently uncharacteristic. A papulonodular eruption, characterized by self-healing skin lesions appearing in crops can often be seen, particularly on extremities. We report on 17 patients, including 2 children. By detailing 6 cases we point out the variable morphologic manifestations, the different courses of disease and therapeutic options.

Need for an improved molecular/genetic classification for CD30+ lymphomas involving the skin.

BACKGROUND: The spectrum of diseases that constitute the CD30+ lymphomas, with lymphomatoid papulosis (LyP) at one end, and anaplastic large-cell lymphoma (ALCL) at the other end, shows variable morphology, immunophenotype, and clinical behavior. The border between these diseases is sometimes difficult to establish and there are many grey zones in their classification. METHODS: We reviewed the clinical and research literature and guided by our experiences attempted to discern molecular and phenotypic criteria to improve the classification and identify molecular targets for therapy of CD30-positive cutaneous lymphomas. RESULTS: Functional studies of ALCL cell lines clonally derived from LyP have revealed loss of growth inhibition by transforming growth factor beta (TGF-beta), due to TGF-beta receptor mutations. Studies of genetic variants of the CD30 promoter showed distinct microsatellite alleles associated with development of LyP and lymphoma progression. Studies of LyP and cutaneous ALCL tissues and cell lines suggest a dual role for CD30/CD30 ligand interactions in regression of LyP and progression to lymphoma. CD30 signaling activates NF-kappaB in cell lines derived from cutaneous ALCL but not anaplastic lymphoma kinase (ALK)-positive systemic ALCL in which growth arrest occurs through cell cycle inhibitor p21WAF1/Cip1. Other likely biomarkers of disease progression include differential expression of Bcl-2, fascin, cutaneous lymphocyte antigen, and T-cell receptor clonality. These may lead to improved classification, diagnoses, and therapeutic targets. CONCLUSIONS: The current clinicopathologic classification of CD30+ cutaneous lymphoproliferative disorders is insufficient. Incorporating genetic and molecular criteria would better define the borders between benign/ malignant and aggressive/nonaggressive disorders.