A small cell variant of ALK-positive, CD8-positive anaplastic large cell lymphoma with primary subcutaneous presentation mimicking subcutaneous panniculitis-like T-cell lymphoma

ALK-positive anaplastic large cell lymphoma (ALK+ ALCL) is an uncommon non-Hodgkin's lymphoma of T-cell origin, the majority of which express CD4 and show frequent pan-T-cell antigen loss. While most cases of ALK+ ALCL have the common pattern characterized by anaplastic morphology with hallmark cells, a less common but well-recognized variant with a small cell pattern may pose a diagnostic challenge. We report a case of ALK+ ALCL with small cell morphology and CD8 subset restriction in a 53-year-old male patient who presented primarily with multiple recurrent subcutaneous nodules with histopathologic features simulating a subcutaneous panniculitis-like T-cell lymphoma (SPTCL). The case was initially diagnosed as SPTCL but was reconsidered as ALK+ ALCL when the incidental finding of CD30 positivity on a subsequent biopsy prompted an ALK immunostain, which turned out to be positive in the neoplastic T-cells. The diagnosis of ALK+ ALCL, small cell variant, was then confirmed by detection of an ALK gene rearrangement by FISH analysis. This report highlights a case of ALK+ ALCL with a deceiving clinical and histopathologic presentation, and emphasizes the value of immunohistochemical panel studies and genetic tests in such cases to avoid diagnostic errors.     

Immunoreactivity of CD99 in non-Hodgkin's lymphoma: unexpected frequent expression in ALK-positive anaplastic large cell lymphoma

To verify the spectrum of CD99-expressing lymphoid malignancy, an immunohistochemical study for CD99 was carried out in 182 cases of non-Hodgkin's lymphoma, including 21 lymphoblastic lymphomas, 11 small lymphocytic lymphomas, 9 mantle cell lymphomas, 12 follicular lymphomas, 37 diffuse large B cell lymphomas, 18 Burkitt's lymphomas, 28 NK/T-cell lymphomas, 8 angioimmunoblastic T-cell lymphomas, 23 peripheral T-cell lymphomas, unspecified, and 15 systemic anaplastic large cell lymphomas. CD99 was positive in all T-lymphoblastic lymphomas and in 60% of B-lymphoblastic lymphomas. Majority of T and NK cell lymphomas were negative for CD99, except anaplastic large cell lymphomas (ALCLs). Eight of 15 cases (54%) of ALCLs reacted with anti CD99 antibody. Seven of 10 (70%) ALK positive ALCLs expressed CD99, whereas only 1 of 5 (20%) ALK negative ALCLs were positive. Of the mature B-cell lymphomas, 5.4% (2/37) of diffuse large B cell lymphomas and 11.1% (2/18) of Burkitt's lymphomas expressed CD99. In conclusion, CD99 is infrequently expressed in mature B and T cell lymphomas, except ALK-positive ALCL. High expression of CD99 in ALK-positive ALCL is unexpected finding and its biologic and clinical significances have yet to be clarified.     

ALK-negative anaplastic large-cell lymphoma demonstrates similar poor prognosis to peripheral T-cell lymphoma, unspecified

AIMS: Anaplastic large cell lymphoma (ALCL) is classically considered a clinicopathological entity separate from other nodal mature T-cell lymphomas (TCL). Recently, the anaplastic lymphoma kinase (ALK) protein was shown to identify a subgroup of nodal ALCL with an excellent prognosis, whereas ALK-negative ALCLs are more heterogeneous. The aim of this study was to investigate the clinicopathological parameters in relation to clinical behaviour of ALK-negative ALCL compared with other nodal mature TCL, i.e. peripheral TCL, unspecified (PTCL-NOS) and angioimmunoblastic lymphoma (AILT). METHODS AND RESULTS: Clinicopathological data of ALK-positive (n = 28) and ALK-negative (n = 46) ALCL; PTCL-NOS (n = 47); and AILT (n = 12) were analysed for their prognostic significance. While ALK-positive ALCL shows favourable clinical features and a good prognosis, ALK-negative ALCL, PTCL-NOS and AILT are all associated with high age groups, advanced disease stage, and poor prognosis (<45% 5-year survival). In multivariate analysis of overall survival time, performed in the combined group of ALK-negative nodal mature T-cell lymphomas, only age and the International Prognostic Index (IPI) remained independent prognostic parameters, while lymphoma subtype (ALCL versus PTCL-NOS versus AILT) gave no additional information. CONCLUSIONS: The distinction between ALK-negative ALCL and PTCL-NOS or AILT is of limited clinical relevance as they show comparable poor prognosis. In these lymphoma subtypes, only age and the IPI are of significant prognostic value.     

间变性淋巴瘤激酶阳性和阴性系统性间变性大细胞淋巴瘤临床病理特征对比研究

目的 探讨间变性淋巴瘤激酶(ALK)阳性和阴性原发性系统性间变性大细胞淋巴瘤(ALCL)与临床病理学特征、免疫表型及分子遗传学之间的差异.方法 收集北京友谊医院病理科2003年lO月至2008年10月活检及会诊中83例ALCL.最后确诊为原发性系统性ALCL 74例,其中有8例未做ALK检测.通过分析临床资料、观察组织形态,采用免疫组织化学EliVision法检测肿瘤细胞表达CD30、ALK、上皮细胞膜抗原(EMA)、CD2、CD3、颗粒酶B/T细胞内抗原(TIA)-1的情况,采用原位杂交的方法检测EB病毒小mRNA,荧光原位杂交(FISH)方法检测染色体是否存在异常.结果 ALK~+ALCL 48例,ALK-ALCL 18例.ALK~+ALCL发病年龄明显较ALK~-ALCL年轻,中位年龄分别为18和36岁,差异有统计学意义(P＜0.05).ALK~+ALCL比ALK~-ALCL患者更多伴有发热症状(33∶4),常常是高热,并且总体存活率(80%∶71%)和中位生存时间(21个月∶12.5个月)更长,但差异均无统计学意义(P＞0.05).ALK~+ALCL更多原发于结内(81%∶56%).ALK~+ALCL和ALK~-ALCL在形态学上差异不明显,多数病例呈弥漫生长,少数表现为结节状生长;66例ALCL中均可以见到标志性细胞,8例有灶状坏死,偶见黏液基质.ALK~+ALCL主要亚型是普通型(35例),其次是淋巴组织细胞型(8例),小淋巴细胞型(3例)和肉瘤型(2例)少见;ALK~-ALCL绝大多数是普通型(17例),仅1例是淋巴组织细胞型.ALK~+ALCL总是同时表达ALK、CD30和EMA;ALK~+ALCL的EMA表达率更高(100%:72%,P＜0.05),ALK~+ALCL的T细胞标记(如CD2/CD3、CD43/CD45RO)的表达率较低,细胞毒性分子表达率较高(P＞0.05).ALCL未检测到EB病毒感染.FISH结果显示4例ALK~+ALCL中1例ALK基因正常,1例基因断裂伴多拷贝,2例仅有断裂;1例ALK~+ALCL中ALK基因正常.结论 ALK~+ALCL与ALK~-ALCL在形态学上没有显著性差异,但在临床特征和免疫表型和分子遗传学特点方面存在一定差异,这些有助于二者的鉴别诊断.     

ALK-positive anaplastic large cell lymphoma in a patient with chronic lymphocytic leukemia

This article reports the case of a 59-year-old patient with an 8-year history of chronic lymphocytic leukemia (CLL), prostate carcinoma, and squamous cell carcinoma who developed an ALK-positive anaplastic large cell lymphoma (ALCL). Lymph node and bone marrow biopsies showed 2 distinct morphologic populations: (a) the CLL component showing a diffuse monomorphous infiltrate of small lymphocytes with the typical immunophenotype showing positive CD20, CD5, CD23, and κ light chain restriction and (b) the ALCL component showing large anaplastic pleomorphic cells positive for CD30, CD45, ALK, CD45Ro, CD4, and vimentin. Polymerase chain reaction performed on the lymph node for immunoglobulin heavy chain and T-cell receptor γ and β showed gene rearrangements after macrodissection of morphologically distinct populations, indicating confirmed genetically distinct populations. Despite intensive chemotherapy, the patient died. This case represents the rare occurrence of an ALK-positive ALCL developing in a patient with CLL.     

Genomic profiling of peripheral T-cell lymphoma, unspecified, and anaplastic large T-cell lymphoma delineates novel recurrent chromosomal alterations

To characterize genetic alterations in peripheral T-cell lymphoma, not otherwise specified (PTCL NOS), and anaplastic large T-cell lymphoma (ALCL), 42 PTCL NOS and 37 ALCL [17 anaplastic large cell kinase (ALK)-negative ALCL, 9 ALK-positive ALCL, 11 cutaneous ALCL] were analyzed by comparative genomic hybridization. Among 36 de novo PTCL NOS, recurrent chromosomal losses were found on chromosomes 13q (minimally overlapping region 13q21, 36% of cases), 6q and 9p (6q21 and 9p21-pter, in 31% of cases each), 10q and 12q (10q23-24 and 12q21-q22, in 28% of cases each), and 5q (5q21, 25% of cases). Recurrent gains were found on chromosome 7q22-qter (31% of cases). In 11 PTCL NOS, high-level amplifications were observed, among them 3 cases with amplification of 12p13 that was restricted to cytotoxic PTCL NOS. Whereas cutaneous ALCL and ALK-positive ALCL showed few recurrent chromosomal imbalances, ALK-negative ALCL displayed recurrent chromosomal gains of 1q (1q41-qter, 46%), and losses of 6q (6q21, 31%) and 13q (13q21-q22, 23%). Losses of chromosomes 5q, 10q, and 12q characterized a group of noncytotoxic nodal CD5+ peripheral T-cell lymphomas. The genetics of PTCL NOS and ALK-negative ALCL differ from other T-NHLs characterized genetically so far, among them enteropathy-type T-cell lymphoma, T-cell prolymphocytic leukemia, and adult T-cell lymphoma/leukemia.     

The nucleophosmin-anaplastic lymphoma kinase fusion protein induces c-Myc expression in pediatric anaplastic large cell lymphomas

The majority of pediatric anaplastic large cell lymphomas (ALCLs) carry the t(2;5)(p23;q35) chromosomal translocation that juxtaposes the dimerization domain of nucleophosmin with anaplastic lymphoma kinase (ALK). The nucleophosmin-ALK fusion induces constitutive, ligand-independent activation of the ALK tyrosine kinase leading to aberrant activation of cellular signaling pathways. To study the early consequences of ectopic ALK activation, a GyrB-ALK fusion was constructed that allowed regulated dimerization with the addition of coumermycin. Expression of the fusion protein caused a coumermycin-dependent increase in cellular tyrosine phosphorylation and c-Myc immunoreactivity, which was paralleled by a rise in c-myc RNA. To assess the clinical relevance of this observation, c-Myc expression was determined in pediatric ALK-positive and -negative lymphomas. Co-expression of c-Myc and ALK was seen in tumor cells in 15 of 15 (100%) ALK-positive ALCL samples, whereas no expression of either ALK or c-Myc was seen in six of six cases of ALK-negative T-cell lymphoma. C-Myc may be a downstream target of ALK signaling and its expression a defining characteristic of ALK-positive ALCLs.     

Fine-needle aspiration biopsy of anaplastic large cell lymphoma, small cell variant with prominent plasmacytoid features: case report

Anaplastic large cell lymphoma (ALCL), according to the new WHO classification, is a diagnosis limited to T/NK cell lymphomas. We present a case that demonstrates a new morphologic variant of ALCL with significant possible pitfalls for the cytopathologist. A fine-needle aspiration biopsy of a cervical lymph node showed a cellular aspiration comprised of medium-sized plasmacytoid cells in a discohesive and focally loosely cohesive pattern. The cytologic diagnosis confirmed the presence of malignancy and noted the prominent plasmacytoid features. An accompanying comment favored melanoma and included a broad differential. No cell block was available for immunohistochemical stains. Immunophenotyping of the subsequent excisional node biopsy showed an anaplastic lymphoma kinase (ALK)-positive ALCL. This case illustrates a new variant of ALCL. Although ALCL variants, such as small cell and lymphohistiocytic, are well recognized, the plasmacytoid features are an additional potential source for misdiagnosis. This case report shows that a cytopathologist should include ALK-positive ALCL in the differential diagnosis of plasmacytoid proliferations cell because of the clinical importance of the ALK-positive ALCL.     

Anaplastic lymphoma kinase-positive anaplastic large cell lymphoma presenting as a bladder neoplasm

Malignant lymphoma presenting in the bladder has been classified in primary cases, as the first sign of disseminated disease and as a secondary infiltration. Most of the examples in the literature have been reported as single cases. Reported herein is the case of a 45-year-old man with an anaplastic large cell lymphoma (anaplastic lymphoma kinase (ALK) and granzyme B positive) that presented as a bladder neoplasm. The morphological differential diagnosis was complex because the EMA-positive immunophenotype, CD45 and CD3 negativity and the clinical manifestation simulated a transitional cell carcinoma. It is important to be aware of its existence because a poorly differentiated bladder carcinoma cannot be ruled out if CD30 and ALK immunostaining are not performed. T-cell receptor-γ clonal rearrangement could be also helpful in these cases. Although bladder involvement by recurrent lymphoma is a sign of widely disseminated disease and it is associated with a very poor prognosis, it seems that chemotherapeutic regimens in this kind of ALK-positive lymphoma could be effective, given that the present patient had an impressive response to chemotherapy treatment.     

ALK-negative anaplastic large cell lymphoma with “Hodgkin-like” cytomorphology and nuclear expression of PAX5

Anaplastic lymphoma kinase negative systemic anaplastic large cell lymphoma (ALK-ALCL) is a CD30+ T-cell malignant lymphoma which may involve both lymph nodes and extranodal tissues, showing important clinical differences from ALK-positive ALCL (ALK + ALCL). ALK- ALCL is considered a specific entity by the 2016 World Health Organization (WHO) classification of hematolymphoid neoplasms.We describe an exceptional case of ALK- ALCL with a striking “Hodgkin-like” cytomorphology and a very uncommon nuclear expression of PAX5.     

原发于骨骼肌的间变性大细胞T细胞淋巴瘤

目的：探讨骨骼肌原发的间变性大细胞淋巴瘤的临床病理特征和免疫表型。方法：采用常规制片和免疫组化(S-P)法检测1例（14岁）骨骼肌原发的间变性大细胞淋巴瘤。结果：肿瘤细胞CD30、ALK-1、CD45RO和CD45阳性；而CD20、EMA、S-100蛋白、desmin和CD68阴性。结论：本例为间变性淋巴瘤激酶（ALK）阳性的间变性大细胞淋巴瘤。骨骼肌原发的间变性大细胞淋巴瘤非常少见，诊断旱应先排除其它肿瘤和其它部位淋巴瘤累及骨骼肌。     

Identification of novel fusion partners of ALK,the anaplastic lymphoma kinase,in anaplastic large-cell lymphoma and inflammatory myofibroblastic tumor

ALK-positive anaplastic large-cell lymphoma (ALCL) has been recognized as a distinct type of lymphoma in the heterogeneous group of T/Null-ALCL. While most of the ALK-positive ALCL (ALKomas) are characterized by the presence of the NPM-ALK fusion protein, the product of the t(2;5)(p23;q35), 10-20% of ALKomas contain variant ALK fusions, including ATIC-ALK, TFG-ALK, CLTC-ALK (previously designated CLTCL-ALK), TMP3-ALK, and MSN-ALK. TMP3-ALK and TMP4-ALK fusions also have been detected in inflammatory myofibroblastic tumors (IMTs), making clear that aberrations of the ALK gene are not associated exclusively with the pathogenesis of ALK-positive ALCL. Here we report results of molecular studies on two lymphoma cases and one IMT case with variant rearrangements of ALK. Our study led to the detection of the CLTC-ALK fusion in an ALCL case and to the identification of two novel fusion partners of ALK: ALO17 (KIAA1618), a gene with unknown function, which was fused to ALK in an ALCL case with a t(2;17)(p23;q25), and CARS, encoding the cysteinyl-tRNA synthetase, which was fused to ALK in an IMT case with a t(2;11;2)(p23;p15;q31). These results confirm the recurrent involvement of ALK in IMT and further demonstrate the diversity of ALK fusion partners, with the ability to homodimerize as a common characteristic.     

Frequent expression of CD30 antigen in the primary gastric non-B, non-Hodgkin lymphomas

Most primary gastric lymphomas are of B-cell origin. Fourteen cases of primary gastric non-B, non-Hodgkin lymphomas were studied to evaluate their clinicopathological and immunophenotypic findings. The cases were comprised of 11 men and three women, with a median age of 56.5 years. Most patients underwent surgery either with or without chemotherapy, exhibiting a 5 year survival rate of 57.5%. Morphologically, the neoplastic cells showed various histological features, such as anaplastic large cell lymphoma (ALCL) (n = 3), peripheral T-cell lymphoma, unspecified, large (n = 4), medium-sized (n = 2) and mixed cell (n = 5). Two cases displayed a non-B, non-T cell phenotype, whereas the remaining cases displayed a T-cell phenotype. Six cases were CD4+, while two were CD8+. The neoplastic cells were CD30+ in 10 cases. TIA-1 was positive in six cases. In one case, anaplastic large cell lymphoma kinase (ALK) was identified with immunostaining and chromosomal rearrangement of ALK was detected by fluorescence in situ hybridization (FISH). In conclusion, although the mechanism of CD30 expression is unknown, primary gastric non-B, non-Hodgkin lymphomas tend to express CD30. We consider that some of the cases in the present study may be derived from cytotoxic T cells, similar to systemic and cutaneous ALCL, the majority of which exhibit TIA-1.     

间变性大细胞淋巴瘤组织间变性淋巴瘤激酶及survivin蛋白表达及其临床意义

目的研究间变性大细胞淋巴瘤（ALCL）中间变性淋巴瘤激酶（ALK）蛋白及survivin蛋白的表达特点及其临床意义。方法应用免疫组织化学LSAB法检测ALK蛋白及survivin蛋白的表达。结果ALK蛋白在81例ALCL中有51例（63％）阳性,30例（37％）阴性。ALK阳性患者预后优于阴性患者（P〈0．05）。survivin蛋白在77例ALCL中均有不同程度的表达,其中高表达33例（42．9％）,低表达44例（57．1％）。survivin的表达与ALK蛋白表达无关（P〉0．05）。预后：Survivin高表达患者较低表达者差（P〈0．05）。在ALK蛋白阳性病例中,survivin高表达患者较低表达者差（P〈0．05）;ALK阴性病例中,survivin的表达状况与预后无关（P〉0．05）。Cox比例风险回归分析表明ALK的表达、体质性症状及survivin的不同表达状况对存活的影响有统计学意义（P〈0．05）,其中ALK的表达对生存的影响最大,survivin表达的影响最小。结论survivin蛋白在ALCL中的表达与ALK蛋白的表达不相关,是一个独立的指标,可有助于判断ALK阳性ALCL病例的预后。     

Cytological features of breast implant‐associated anaplastic large cell lymphoma in pleural effusion

Breast implant‐associated anaplastic large cell lymphoma (BIA‐ALCL) is a very rare CD30‐positive ALK‐negative T‐cell non‐Hodgkin lymphoma included as a provisional entity in the 2017 WHO classification of lymphoid neoplasms. BIA‐ALCL arises as proliferating cells over the surface of the implant. It is generally an indolent disease if confined within the fibrous capsule. In contrast, mass and/or infiltration beyond the capsule is much more aggressive. This report describes a case of infiltrative BIA‐ALCL with massive pleural effusion containing hallmark BIA‐ALCL cells showing the characteristic morphologic appearance of high‐grade anaplastic lymphoma, CD30‐positive but ALK‐negative with variable staining for T‐cell antigens. Detailed cytological features of BIA‐ALCL in pleural fluid are described along with the results of a literature search performed for BIA‐ALCL cases with pleural effusion. This report expands the spectrum of BIA‐ALCL pathology to include chest wall involvement and pleural effusion.     

Frequent expression of the NPM-ALK chimeric fusion protein in anaplastic large-cell lymphoma,lympho-histiocytic type.

The revised European-American lymphoma classification recognizes a subtype of anaplastic large-cell lymphoma (ALCL), termed lympho-histiocytic because of its peculiar cytological composition. As in the case of classical ALCL, this tumor usually occurs in young patients and shows an excellent response to chemotherapy, but some authors have suggested that in reality this is a nonanaplastic T-cell lymphoma rich in histiocytes. In this paper, we show that three of five cases of lympho-histiocytic ALCL stain with anti-ALK antibodies and can therefore be presumed to express the chimeric NPM/ALK protein secondary to (2;5) translocation. These findings further support the inclusion of this as a type of ALCL and not among the nonanaplastic peripheral T-cell lymphomas. Furthermore, they indicate that staining for ALK proteins is a powerful tool for the diagnosis of lympho-histiocytic ALCL, the recognition of which may be difficult on morphological grounds.     

Absence of Epstein-Barr virus in anaplastic large cell lymphoma: a study of 64 cases classified according to World Health Organization criteria

The frequency of Epstein-Barr virus (EBV) in anaplastic large cell lymphoma (ALCL) has been controversial. The interpretation of previous studies is complicated by the use of nonuniform EBV detection methods and the inclusion of cases of CD30-positive diffuse large B-cell lymphoma and so-called "ALCL, Hodgkin-like," as defined in the Revised European-American Lymphoma classification scheme. In the current World Health Organization (WHO) classification system, both of these tumors are excluded from the ALCL category. Also, recently developed antibodies (eg, the antibody specific for PAX-5/B-cell-specific activator protein [BSAP]) provide new, sensitive tools for identifying neoplasms of B-cell lineage that can morphologically resemble ALCL. In this study we evaluated 64 cases of ALCL of T- or null-cell lineage, defined according to the WHO classification system, for the presence of EBV. All tumors were negative for B-cell antigens, including PAX-5/BSAP and CD20 or CD79a. The study group included 27 (42%) anaplastic lymphoma kinase (ALK)-positive (18 T-cell and 9 null-cell) and 37 (58%) ALK-negative (30 T-cell and 7 null-cell) tumors analyzed by in situ hybridization for EBV-encoded RNA (EBER) or immunohistochemistry for EBV-latent membrane protein type 1. All 64 cases were negative for EBV. We conclude, based on the current definition of ALCL in the WHO classification, there is no role for EBV in ALCL arising in Western patients. We suggest that published reports of EBV in a small proportion of ALCL cases in Western patients can be explained by the inclusion of tumors no longer considered to be in the current classification of ALCL, such as CD30-positive anaplastic tumors of B-cell origin.     

Primary anaplastic large cell lymphoma of the small intestine.

We describe the clinicopathologic, immunophenotypic, and molecular findings in 4 cases of anaplastic large cell lymphoma (ALCL) arising in the small intestine. All patients were men with acute symptoms of gastrointestinal tract obstruction. The clinical preoperative diagnosis was gastrointestinal carcinoma in 3 cases, and pancreatic carcinoma in 1 case. Histologic examination revealed cohesive aggregates of neoplastic cells, with multiple vesicular nuclei, prominent nucleoli, and abundant amphophilic cytoplasm. There was no clinical or histopathologic evidence of enteropathy. All cases were CD30+, and all showed evidence of T-cell lineage with cytotoxic potential by expression of CD3, CD43, or CD45RO; T-cell intracellular antigen-1; or perforin. One tumor showed p80 and anaplastic lymphoma kinase (ALK) overexpression corroborated by the presence of the t(2:5). One tumor expressed Epstein-Barr virus latent membrane protein. In all cases, the tumor cells were negative for CD20, CD15, CD56, and cytokeratin. Polymerase chain reaction revealed clonal rearrangements of the T-cell receptor gamma-chain gene, without evidence of immunoglobulin heavy-chain gene rearrangement. The diagnosis of primary bowel ALCL is facilitated by immunophenotypic and molecular studies. With 24 months of clinical follow-up, only the patient with the t(2:5)-positive tumor is alive and free of disease, suggesting that p80/ALK overexpression may be a good prognostic indicator.