Peripheral T-cell lymphomas expressing CD30 and CD15 expand the spectrum of anaplastic large cell lymphoma, ALK-negative

Peripheral T-cell lymphomas (PTCL) are morphologically and biologically heterogeneous and a subset expresses CD30, including anaplastic large cell lymphomas (ALCL) and a minority of PTCL, not otherwise specified (PTCL, NOS). ALCL with ALK translocations (ALCL, ALK+) are readily identified by routine diagnostic methods, but differentiating ALCL without ALK translocation (ALCL, ALK-) and PTCL, NOS expressing CD30 (PTCL CD30+) can be challenging. Furthermore, rare PTCL co-express CD30 and CD15 (PTCL CD30+CD15+); some resemble ALCL, ALK- while others resemble classic Hodgkin lymphoma. To explore the relationship between PTCL CD30+CD15+ and ALCL, ALK-, we analysed 19 cases of PTCL with CD30 expression, previously diagnosed as ALCL, ALK- (nine cases) and PTCL CD30+CD15+ (10 cases) for DUSP22/IRF4 rearrangements, coding RNA expression and selected transcriptome analysis using the NanoString nCounter gene expression analysis platform. Unsupervised clustering showed no clear segregation between ALCL, ALK- and PTCL CD30+CD15+. Three cases previously classified as PTCL CD30+CD15+ showed DUSP22/IRF4 rearrangements, favouring a diagnosis of ALCL, ALK-. Our results suggest that cases previously designated PTCL CD30+CD15+, likely fall within the spectrum of ALCL, ALK-; additionally, a subset of ALCL, ALK- with DUSP22/IRF4 rearrangement expresses CD15, consistent with previous reports and expands the immunophenotypic spectrum of this lymphoma subgroup.

Molecular Screening in Anaplastic Lymphoma Kinase-Positive Anaplastic Large Cell Lymphoma: Anaplastic Lymphoma Kinase Analysis, Next-Generation Sequencing Fusion Gene Detection, and T-Cell Receptor Immunoprofiling

Anaplastic lymphoma kinase-positive anaplastic large cell lymphoma (ALK+ ALCL) originates from the T-lineage and is marked by rearrangements of the ALK gene. More than 10 fusion partners with the ALK gene are known, with the most common being the t(2;5)(p23;q35) translocation resulting in the NPM1::ALK fusion. In 10% to 20% of the ALK+ ALCL cases, the ALK gene fuses with various other partners. Modern molecular techniques, especially next-generation sequencing (NGS), have eased the identification of ALK gene fusion partners and have allowed in-depth characterization of the T-cell receptor (TCR) repertoire. We devised a real-time quantitative reverse-transcription polymerase chain reaction to measure the expression of the translocated portion of the ALK gene. Fusion partners for the ALK gene were analyzed using rapid amplification of 5'cDNA ends (RACE) method or NGS. TCR immunoprofiling was performed by amplicon NGS. We studied 96 ALK+ ALCL patients. NPM1::ALK fusion gene was observed in 71 patients, ATIC::ALK in 9, and TPM3::ALK in 3. CLTC::ALK, MYH9::ALK, and RNF213::ALK fusions were identified in 2 patients each. We also discovered the TPM4::ALK and SATB1::ALK fusion genes, plus the following 2 previously unidentified ALK+ ALCL fusions: SQSTM1::ALK and CAPRIN1::ALK. High expression of the translocated ALK gene segment was observed in all 93 analyzed samples. TCR testing was conducted on 23 patients with available DNA. In 18 (78%) patients, we discerned at least one (ranging from 1 to 4) clonal TCR rearrangement. In 59% of the patients, clonal TCR beta junctions corresponded with sequences previously observed in both healthy donors and under various pathological conditions. Reverse-transcriptase quantitative detection of ALK expression is a fast and reliable method for both diagnosing and monitoring treatment response in ALK+ ALCL patients, irrespective of the ALK gene translocation. NGS reveals new ALK translocation partners. Both malignant and reactive TCR repertoires in ALK+ ALCL patients are unique and do not consistently occur among different patients.

Malignancy-Associated Secondary Hemophagocytic Lymphohistiocytosis Mimicking an Infection: A Case Report and Review of the Literature

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening hematological disorder of immune dysregulation associated with significant challenges in diagnosis and management. Described as primary HLH secondary to genetic defects or more commonly secondary to infections, it can also occur secondary to malignancy, i.e., malignancy-associated hemophagocytic lymphohistiocytosis (M-HLH). A five-year-old male child presented with left cervical adenopathy and a high-spiking fever for two weeks. He had pallor, anasarca, multiple enlarged and matted cervical lymph nodes, respiratory distress, and hepatomegaly. He had continuous high-grade fever spikes (maximum 105 °F), not touching baseline despite broad-spectrum antibiotics. The CBC revealed anemia with thrombocytopenia. Liver function tests showed mild transaminitis and hypoalbuminemia. The HLH workup showed elevated ferritin, low fibrinogen, and elevated triglycerides. Lymph node biopsy showed intermediate to large atypical monomorphic lymphocyte cells with ALK, CD30, CD5, CD3, CD45, and BCL-2 (weak positive) positivity and Ki-67-95%, suggestive of anaplastic large cell lymphoma (ALCL). The bone marrow aspiration showed reactive marrow with hemophagocytosis. The patient was started on dexamethasone and chemotherapy per the Children's Oncology Group's (COG) ALCL protocol. He showed remarkable clinical improvement and went into remission after the induction phase. Malignancy associated with HLH can mimic infection, as in our patient with high-spiking fever, consolidation, and mediastinal adenopathy. A high index of suspicion is necessary to arrive at an appropriate, early diagnosis, and workup for malignancy is to be considered when an infectious etiology is not identified after thorough evaluation.

Role of flow cytometric immunophenotyping in the diagnosis of breast implant-associated anaplastic large cell lymphoma: A 6-year, single-institution experience

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is an uncommon mature T-cell neoplasm occurring in patients with textured breast implants, typically after 7-10 years of exposure. Although cytopathologic or histopathologic assessment is considered the gold standard diagnostic method for BIA-ALCL, flow cytometry (FC)-based immunophenotyping is recommended as an adjunct test. However, the diagnostic efficacy of FC is not well reported. We reviewed 290 FC tests from breast implant pericapsular fluid and capsule tissue from 182 patients, including 16 patients with BIA-ALCL over a 6-year period, calculating diagnostic rates and test efficacy. FC showed an overall sensitivity of 75.9%, specificity of 100%, and negative and positive predictive values of 95.4% and 100%, respectively. Blinded expert review of false-negative cases identified diagnostic pitfalls, improving sensitivity to 96.6%. Fluid samples had better rates of adequate samples for FC testing compared with tissue samples. Paired with FC testing of operating room (OR)-acquired fluid samples, capsulectomy FC specimens added no diagnostic value in patients with concurrent fluid samples; no cases had positive capsule FC with negative fluid FC. Fluid samples are adequate for FC testing more often than tissue. Capsule tissue FC specimens do not improve FC efficacy when paired with OR-acquired fluid FC samples and are often inadequate samples. FC is 100% specific for BIA-ALCL and can serve as a confirmatory test but should not be the sole diagnostic method. Awareness of sample-specific diagnostic pitfalls greatly improves the sensitivity of BIA-ALCL testing by FC.

Case report: The utilization of crizotinib and brentuximab vedotin as a bridge to autologous stem cell transplantation and followed by CD30-directed CAR-T cell therapy in relapsed/refractory ALK+ ALCL

Background

Anaplastic lymphoma kinase-positive anaplastic large cell lymphoma (ALK+ ALCL) is a rare, mature T-cell non-Hodgkin lymphoma. The prognosis of patients with relapsed or refractory ALCL following first-line chemotherapy is extremely poor. NCCN guidelines recommend intensified chemotherapy with or without ASCT consolidation for r/r ALCL, however, this is not an effective treatment for all ALK+ALCL.

Case report

Herein, we report a patient with relapsed/refractory ALK+ ALCL who received crizotinib and brentuximab vedotin as bridging therapy, followed by autologous stem cell transplantation and sequential anti-CD30 CAR T cell therapy.

Conclusion

The patient achieved complete remission and long-term disease-free survival of months and continues to be followed up. The combination therapy model in this case may provide guidance for the management of relapsed/refractory ALK+ ALCL, and further prospective trials are needed to confirm its effectiveness.

Primary Cutaneous CD30-Positive Lymphoproliferative Disorders-Current Therapeutic Approaches with a Focus on Brentuximab Vedotin

One of the most common subgroups of cutaneous T-cell lymphomas is that of primary cutaneous CD30-positive lymphoproliferative disorders. The group includes lymphomatoid papulosis (LyP) and primary cutaneous anaplastic large cell lymphoma (pcALCL), as well as some borderline cases. Recently, significant progress has been made in understanding the genetics and treatment of these disorders. This review article summarises the clinical evidence supporting the current treatment options for these diseases. Recent years have seen the introduction of novel agents into clinical practice; most of these target CD30, such as anti-CD30 monoclonal antibodies and conjugated antibodies (brentuximab vedotin), bispecific antibodies and cellular therapies, particularly anti-CD30 CAR-T cells. This paper briefly reviews the biology of CD30 that makes it a good therapeutic target and describes the anti-CD30 therapies that have emerged to date.

Detection of TRAF1-ALK fusion in skin lesions of systemic ALK+ anaplastic large cell lymphoma initially involving the skin and the draining lymph node

A case of cytoplasmic anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL) initially involving the skin in a 44-year-old Japanese female is reported. The patient had a hemorrhagic erythematous tumor on the right thigh without any systemic symptoms. Pathology showed diffuse infiltration of CD30-positive anaplastic large cells positive for epithelial membrane antigen and cytoplasmic ALK. The right inguinal lymph node showed infiltration of tumor cells in the marginal sinus. Only 2 weeks after radiation therapy, the patient developed multiple subcutaneous nodules and lung involvement. Even after subsequent multichemotherapy sessions, cutaneous recurrence occurred. Literature review of cytoplasmic ALK-positive ALCL initially involving in the skin revealed that skin lesions were mostly seen in the extremities and that half of the cases developed extracutaneous lesions. Radiation and chemotherapy were effective for most cases. Inverse RT-PCR identified a tumor necrosis factor receptor-associated factor (TRAF)1-ALK fusion in our case. Most reported cases with this translocation experienced repeated changes in chemotherapy, suggesting poorer prognosis. Although ALK-positive ALCL generally responds well to chemotherapy, the presence of a TRAF1-ALK fusion may suggest resistance to treatment. Detection of fusion partners of ALK is important for predicting clinical courses and deciding treatment options.

From Development to Place in Therapy of Lorlatinib for the Treatment of ALK and ROS1 Rearranged Non-Small Cell Lung Cancer (NSCLC)

Following the results of the CROWN phase III trial, the third-generation macrocyclic ALK inhibitor lorlatinib has been introduced as a salvage option after the failure of a first-line TKI in ALK-rearranged NSCLC, while its precise role in the therapeutic algorithm of ROS1 positive disease is still to be completely defined. The ability to overcome acquired resistance to prior generation TKIs (alectinib, brigatinib, ceritinib, and crizotinib) and the high intracranial activity in brain metastatic disease thanks to increased blood-brain barrier penetration are the reasons for the growing popularity and interest in this molecule. Nevertheless, the major vulnerability of this drug resides in a peculiar profile of related collateral events, with neurological impairment being the most conflicting and debated clinical issue. The cognitive safety concern, the susceptibility to heterogeneous resistance pathways, and the absence of a valid alternative in the second line are strongly jeopardizing a potential paradigm shift in this oncogene-addicted disease. So, when prescribing lorlatinib, clinicians must face two diametrically opposed characteristics: a great therapeutic potential without the intrinsic limitations of its precursor TKIs, a cytotoxic activity threatened by suboptimal tolerability, and the unavoidable onset of resistance mechanisms we cannot properly manage yet. In this paper, we give a critical point of view on the stepwise introduction of this promising drug into clinical practice, starting from its innovative molecular and biochemical properties to intriguing future developments, without forgetting its weaknesses.

Strategy for Pediatric Patients with Relapsed or Refractory Anaplastic Lymphoma Kinase-Positive Anaplastic Large Cell Lymphoma: A Review

Anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL) is an aggressive T-cell lymphoma characterized by large T-cells with strong CD30 and ALK expression. Although conventional chemotherapy is effective in most patients, approximately 30% experience a relapse or refractory disease and have a poor prognosis. Several risk factors associated with poor prognosis have been identified in pediatric ALK-positive ALCL. These include morphological patterns with the small cell variant or lymphohistiocytic variant, leukemic presentation, the presence of minimal disseminated disease, or involvement of the central nervous system. Relapsed or refractory ALK-positive ALCL is often resistant to conventional chemotherapy; therefore, salvage therapy is required. In recent years, targeted therapies such as ALK inhibitors and brentuximab vedotin (BV) have been developed. ALK inhibitors block the continuous activation of ALK kinase, a driver mutation that leads to cell proliferation in ALK-positive ALCL. Additionally, BV is an antibody-drug conjugate that targets CD30-positive cells. Both ALK inhibitors and BV have displayed dramatic effects in chemoresistant ALK-positive ALCL. Weekly vinblastine treatment and hematopoietic stem cell transplantation have also been reported to be effective therapies. This article reviews pediatric ALK-positive ALCL, focusing on risk factors and treatment strategies for pediatric patients with relapsed or refractory ALK-positive ALCL.

CD30+ lymphoproliferative disorder masquerading as an atypical melanocytic proliferation

Heuristics are cognitive strategies used to facilitate decision-making. They can be helpful tools for expediting pathologic diagnoses, however, they can also affect judgment and lead to biases that guide the pathologist astray. We report the case of a 52-year-old female who presented with two unusual pigmented lesions on the wrist and thigh that clinically and histopathologically resembled an atypical melanocytic proliferation. A biopsy of the thigh revealed a broad proliferation of large, atypical cells forming nests within a heavily pigmented epidermis. The lesion was initially misdiagnosed as melanoma in situ, despite equivocal staining for melanocytic markers, likely due to anchoring and adjustment as well as availability biases, which restricted the differential diagnosis and limited the selection of immunohistochemical stains. It was later discovered through chart review that the patient had a prior history of a cutaneous CD30+ lymphoproliferative disorder, which eventually led to the appropriate diagnosis in this case. Herein, we highlight a rare and unusual presentation of a pigmented epidermotropic CD30+ lymphoproliferative disorder, along with the biases leading to its misdiagnosis and the steps leading to the revelation of the actual diagnosis.

Anaplastic Large-Cell Lymphoma With Vitreous Humor Involvement

Purpose: To describe a case of T-cell lymphoma with bilateral vitreous involvement. Methods: A case report was reviewed, and a literature review, including search terms such as "anaplastic large-cell lymphoma (ALCL)" and "T-cell lymphoma with ocular involvement", was performed. Results: A 56-year-old man presented with slurred speech, left-sided weakness, and floaters in his right eye. He was found to have an enhancing right frontal lobe mass with biopsy positive for ALCL. The right eye demonstrated 2+ vitreous cell, with a vitreous biopsy consistent with ALCL. His floaters resolved, and the patient was asymptomatic until he developed floaters in his left eye 1½ years later. A subsequent vitreous biopsy revealed recurrence of ALCL in the fellow eye. Conclusions: ALCL is a rare T-cell lymphoma uncommonly reported as having vitreous infiltration.

Leukaemic Presentation of Small-Cell Alk-Positive Anaplastic Large Cell Lymphoma in a Young Woman-Report of a Case with 9-Year Survival

Anaplastic large cell lymphoma (ALCL) with leukaemic presentation (either ab initio or along the course of the disease) has been rarely reported. Irrespective of ALK expression in the neoplastic cells, it features a dismal prognosis. We report a rare case of leukaemic, small cell variant ALK-positive ALCL with 9-year survival in a young woman who was treated upfront with corticosteroids and standard chemotherapy, and review thoroughly the previously published cases. Such an unexpected, good outcome hints at the existence of different clinical subgroups in the leukaemic variant of ALK-positive ALCL.

Cutaneous Intravascular CD-30-Positive Anaplastic Large Cell Lymphoma: A Case Report and Literature Review

Intravascular cutaneous anaplastic large cell lymphoma (ALCL) is an extremely rare non-Hodgkin lymphoma that proliferates in the lumen of small blood vessels and has a propensity to manifest in the skin. Most reported cases of intravascular lymphoma described in the literature are of large B-cell lymphomas, making T-cell lymphomas incredibly rare. As such, we present the case of an 87-year-old male with primary cutaneous intravascular anaplastic large T-cell lymphoma that initially presented with an erythematous, subcutaneous nodule on the right mid-abdomen. We report the immunohistochemical results showing lymphoma cells staining positively for CD3 and CD30 and lacking expression of anaplastic lymphoma kinase, pan-cytokeratin, CD10, CD20, and SOX10. We also review and compare previously reported cases of intravascular ALCL with primary cutaneous involvement.

The Polyvalent Role of CD30 for Cancer Diagnosis and Treatment

CD30, also known as TNFRSF8 (tumor necrosis factor receptor superfamily member 8), is a protein receptor that is heavily glycosylated inside the Golgi apparatus, as well as a tumor marker that is found on the surface of specific cells in the body, including certain immune cells and cancer ones. This review aims to shed light on the critical importance of CD30, from its emergence in the cell to its position in diagnosing various diseases, including Hodgkin lymphoma, where it is expressed on Hodgkin and Reed-Sternberg cells, as well as embryonal carcinoma, anaplastic large cell lymphoma (ALCL), and cutaneous T-cell lymphoma (CTCL). In addition to its role in positive diagnosis, targeting CD30 has been a promising approach treating CD30-positive lymphomas, and there is ongoing research into the potential use of CD30-targeted therapies for autoimmune disorders. We aim to elaborate on CD30's roles as a tumor marker, supporting thus the hypothesis that this receptor might be the aim of cytostatic treatment.

Phosphorylated STAT3 as a potential diagnostic and predictive biomarker in ALK- ALCL vs. CD30high PTCL, NOS

Aims

The differential diagnosis between ALK-negative anaplastic large cell lymphoma (ALK- ALCL) and peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) with high expression of CD30 (CD30high) are essential. However, no reliable biomarker is available in daily practice except CD30. STAT3 is characteristically activated in ALCL. We aimed to investigate whether the status of STAT3 phosphorylation could help the differential diagnosis.

Methods

The status of phosphorylation of STAT3 was examined using two antibodies against pSTAT3-Y705 and pSTAT3-S727 by immunohistochemistry in ALK+ ALCL (n=33), ALK- ALCL (n=22) and PTCL, NOS (n=34). Ten PTCL, NOS with diffuse CD30 expression were defined as CD30high PTCL, NOS. Flowcytometric analysis were performed to evaluate the expression of pSTAT3-Y705/S727 in PTCL, NOS (n=3).

Results

The median H-scores of pSTAT3-Y705 and S727 were 280 and 260 in ALK+ ALCL, 250 and 240 in ALK- ALCL, and 45 and 75 in CD30high subgroup, respectively. Using H score of 145 as the cutoff value, pSTAT3-S727 alone distinguished between ALK- ALCL and CD30high PTCL, NOS with a sensitivity of 100% and specificity of 83%. Additionally, pSTAT3-S727, but not pSTAT3-Y705, was also expressed by background tumor-infiltrating lymphocytes (S727TILs) in PTCL, NOS. PTCL, NOS patients with high S727TILs H score had a favorable prognosis than those with no TILs (3-year OS rate: 43% vs. 0, p=0.013) or low S727TILs (3-year OS rate: 43% vs. 0, p=0.099). Flowcytometric analysis revealed that of the three patients investigated, two had enhanced pSTAT-S727 signals in neoplastic cell populations, and all three patients were negative for pSTAT3-Y705 expression in both tumor cells and background lymphocytes.

Conclusions

pSTAT3-Y705/S727 can be used to help distinguish ALK- ALCL from CD30high PTCL, NOS and pSTAT3-S727 expression by TILs predicts the prognosis of a subset of PTCL, NOS.

Effect of arsenic trioxide plus etoposide, solumedrol, high‑dose cytarabine and cisplatin chemotherapy on the treatment of relapsed or ref7ractory ALK+ anaplastic large cell lymphoma

It has been reported that arsenic trioxide (ATO) regulates lymphoma cell cycle, apoptosis, autophagy and mitochondrial activity, while it synergizes with other cytotoxic agents. In addition, ATO targets anaplastic lymphoma kinase (ALK)-fusion oncoprotein to repress anaplastic large cell lymphoma (ALCL). The current study aimed to investigate the efficacy and safety of ATO plus etoposide, solumedrol, high-dose cytarabine and cisplatin (ESHAP) chemotherapy compared with ESHAP chemotherapy alone in patients with relapsed or refractory (R/R) ALK⁺ ALCL. A total of 24 patients with R/R ALK⁺ ALCL were enrolled in the present study. Among them, 11 patients were treated with ATO plus ESHAP, while the remaining 13 patients received ESHAP chemotherapy alone. Subsequently, treatment response, event-free survival (EFS), overall survival (OS) and adverse event (AEs) rates were recorded. Both complete response (72.7% vs. 53.8%; P=0.423) and objective response (81.8% vs. 69.2%; P=0.649) rates were higher in the ATO plus ESHAP group compared with the ESHAP group. However, statistical significance was not reached. In addition, EFS was significantly prolonged (P=0.047), while OS was not significantly increased (P=0.261) in the ATO plus ESHAP group compared with the ESHAP group. More specifically, the 3-year accumulating EFS and OS rates were 59.7 and 77.1% in the ATO plus ESHAP group, respectively, and 13.8 and 59.8% in the ESHAP group, respectively. The majority of AEs, such as thrombocytopenia (81.8% vs. 46.2%; P=0.105), fever (81.8% vs. 46.2%; P=0.105) and dyspnea (36.4% vs. 15.4%; P=0.182), were more prevalent in the ATO plus ESHAP group compared with the ESHAP group. However, no statistical significance was observed. In conclusion, the current study indicated that ATO plus ESHAP chemotherapy could exert a superior efficacy compared with ESHAP chemotherapy alone in patients with R/R ALK⁺ ALCL.

Future Perspective for ALK-Positive Anaplastic Large Cell Lymphoma with Initial Central Nervous System (CNS) Involvement: Could Next-Generation ALK Inhibitors Replace Brain Radiotherapy for the Prevention of Further CNS Relapse?

Central nervous system (CNS) involvement in anaplastic large cell lymphoma (ALCL) at diagnosis is rare and leads to poor prognosis with the use of the standard ALCL99 protocol alone. CNS-directed intensive chemotherapy, such as an increased dose of intravenous MTX, increased dose of dexamethasone, intensified intrathecal therapy, and high-dose cytarabine, followed by cranial irradiation, has been shown to improve survival in this population. In this paper, the authors describe a 14-year-old male with an intracranial ALCL mass at onset who received CNS-directed chemotherapy followed by 23.4 Gy of whole-brain irradiation. After the first systemic relapse, the CNS-penetrating ALK inhibitor, alectinib, was applied; it has successfully maintained remission for 18 months without any adverse events. CNS-penetrating ALK inhibitor therapy might prevent CNS relapse in pediatric ALK-positive ALCL. Next-generation ALK inhibitors could be introduced as a promising treatment option, even for primary ALCL with CNS involvement, which could lead to the omission of cranial irradiation and avoid radiation-induced sequalae. Further evidence of CNS-penetrating ALK inhibitor combined therapy for primary ALK-positive ALCL is warranted to reduce radiation-induced sequalae in future treatments.

Brentuximab vedotin use in pediatric anaplastic large cell lymphoma

Anaplastic large cell lymphoma (ALCL) is the most common type of mature T-cell non-Hodgkin lymphoma in children/adolescents. ALCL is characterized by expression of CD30 in the neoplastic lymphoid cells with frequent expression of anaplastic lymphoma kinase (ALK), especially within the pediatric population. Despite multiple efforts to optimize the use of conventional chemotherapy, outcomes in children, adolescents, and adults with ALCL remain suboptimal. Thus, there is a need to improve survival for those with high-risk disease and decrease therapy exposures and toxicities for those with low-risk disease. Targeted therapies, such as the anti-CD30 antibody-drug conjugate, brentuximab vedotin, are new important therapeutic options. Phase I and II studies in adults with relapsed/refractory CD30⁺ lymphomas, including ALCL, demonstrated the safety and efficacy of brentuximab vedotin, leading to FDA approval for relapsed/refractory ALCL in adults and successful incorporation into frontline therapies. Clinical trials in the pediatric population demonstrated similar results in those with relapsed/refractory ALCL. Incorporation of brentuximab vedotin into upfront therapy for children and adolescents with ALCL showed that this novel combination therapy has clinical advantages in comparison to conventional agents alone. Brentuximab vedotin is well-tolerated in both the pediatric and adult populations, even when used in combination with conventional agents. Brentuximab vedotin is an ideal agent to treat ALCL with excellent targeted activity and limited toxicity. Future studies are needed to identify how brentuximab vedotin should be utilized when combined with immunotherapy or other targeted agents (e.g., ALK inhibitors) in both the upfront and relapsed/refractory setting.

The Role of Microorganisms in the Development of Breast Implant-Associated Anaplastic Large Cell Lymphoma

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a variant of anaplastic large cell lymphoma (ALCL) associated with textured-surface silicone breast implants. Since first being described in 1997, over 1100 cases have been currently reported worldwide. A causal relationship between BIA-ALCL and textured implants has been established in epidemiological studies, but a multifactorial process is likely to be involved in the pathogenesis of BIA-ALCL. However, pathophysiologic mechanisms remain unclear. One of the hypotheses that could explain the link between textured implants and BIA-ALCL consists in the greater tendency of bacterial biofilm in colonizing the surface of textured implants compared to smooth implants, and the resulting chronic inflammation which, in predisposed individuals, may lead to tumorigenesis. This review summarizes the existing evidence on the role of micro-organisms and rough surface implants in the development of BIA-ALCL. It also provides insights into the most updated clinical practice knowledge about BIA-ALCL, from clinical presentation and investigation to treatment and outcomes.

Tyrosine kinases in nodal peripheral T-cell lymphomas

Nodal peripheral T-cell lymphomas (PTCL) are uncommon and heterogeneous tumors characterized by a dismal prognosis. Targeted therapy has been proposed. However, reliable targets are mostly represented by a few surface antigens (e.g., CD52 and CD30), chemokine receptors (e.g., CCR4), and epigenetic gene expression regulation. In the last two decades, however, several studies have supported the idea that tyrosine kinase (TK) deregulation might be relevant for both the pathogenesis and treatment of PTCL. Indeed, they can be expressed or activated as a consequence of their involvement in genetic lesions, such as translocations, or by ligand overexpression. The most striking example is ALK in anaplastic large-cell lymphomas (ALCL). ALK activity is necessary to support cell proliferation and survival, and its inhibition leads to cell death. Notably, STAT3 was found to be the main downstream ALK effector. Other TKs are consistently expressed and active in PTCLs, such as PDGFRA, and members of the T-cell receptor signaling family, such as SYK. Notably, as in the case of ALK, STAT proteins have emerged as key downstream factors for most of the involved TK.

Regulation of CD45 phosphatase by oncogenic ALK in anaplastic large cell lymphoma

Anaplastic Large Cell Lymphoma (ALCL) is a subtype of non-Hodgkin lymphoma frequently driven by the chimeric tyrosine kinase NPM-ALK, generated by the t (2,5)(p23;q35) translocation. While ALK+ ALCL belongs to mature T cell lymphomas, loss of T cell identity is observed in the majority of ALCL secondary to a transcriptional and epigenetic repressive program induced by oncogenic NPM-ALK. While inhibiting the expression of T cell molecules, NPM-ALK activates surrogate TCR signaling by directly inducing pathways downstream the TCR. CD45 is a tyrosine phosphatase that plays a central role in T cell activation by controlling the TCR signaling and regulating the cytokine responses through the JAK/STAT pathway and exists in different isoforms depending on the stage of T-cell maturation, activation and differentiation. ALK+ ALCL cells mainly express the isoform CD45RO in keeping with their mature/memory T cell phenotype. Because of its regulatory effect on the JAK/STAT pathway that is essential for ALK+ ALCL, we investigated whether CD45 expression was affected by oncogenic ALK. We found that most ALK+ ALCL cell lines express the CD45RO isoform with modest CD45RA expression and that NPM-ALK regulated the expression of these CD45 isoforms. Regulation of CD45 expression was dependent on ALK kinase activity as CD45RO expression was increased when NPM-ALK kinase activity was inhibited by treatment with ALK tyrosine kinase inhibitors (TKIs). Silencing ALK expression through shRNA or degradation of ALK by the PROTAC TL13-112 caused upregulation of CD45RO both at mRNA and protein levels with minimal changes on CD45RA, overall indicating that oncogenic ALK downregulates the expression of CD45. CD45 repression was mediated by STAT3 as demonstrated by ChIP-seq data on ALCL cells treated with the ALK-TKI crizotinib or cells treated with a STAT3 degrader. Next, we found that knocking-out CD45 with the CRISPR/Cas9 system resulted in increased resistance to ALK TKI treatment and CD45 was down-regulated in ALCL cells that developed resistance in vitro to ALK TKIs. Overall, these data suggest that CD45 expression is regulated by ALK via STAT3 and acts as a rheostat of ALK oncogenic signaling and resistance to TKI treatment in ALCL.

Allogeneic haematopoietic cell transplant in patients with relapsed/refractory anaplastic large cell lymphoma

The prognosis of relapsed/refractory (R/R) anaplastic large cell lymphoma (ALCL) is poor. Large studies evaluating outcomes of allogeneic haematopoietic cell transplantation (allo-HCT) in systemic R/R ALCL are not available. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we evaluated outcomes of 182 adults (aged ≥18 years) with R/R ALCL undergoing allo-HCT between 2008 and 2019. Non-relapse mortality (NRM), disease relapse/progression (REL), progression-free survival (PFS), and overall survival (OS) were modelled using Cox proportional hazards models. The median (range) follow-up of survivors was 62 (3-148) months. The 1-year NRM was 18%. The 5-year REL, PFS and OS were 32%, 41% and 56% respectively. On multivariable regression analysis African American race (hazard ratio [HR] 2.7, 95% confidence interval [CI] 1.6-4.8; p < 0.001) and refractory disease at allo-HCT (HR 3.2, 95% CI 1.6-6.2; p < 0.001) were predictive of inferior OS. Similarly, African-American race (HR 2.1, 95% CI 1.3-3.4; p = 0.003), other minority race (HR 2.5, 95% CI 1.2-5.3; p = 0.02) and refractory disease (HR 2.2, 95% CI 1.2-4.3; p = 0.01) were predictive of inferior PFS. These data, demonstrate that allo-HCT can result in durable disease control in a sizable proportion of patients with R/R ALCL. Refractory disease and racial minority status predicted inferior allo-HCT outcomes. Whether the inferior outcomes of racial minorities with R/R ALCL after allo-HCT are driven by differences in disease biology or disparities in post allo-HCT care, or both, requires further investigation.

Challenges in nodal peripheral T-cell lymphomas: from biological advances to clinical applicability

T cell lymphomas are a heterogenous group with varying biological and clinical features that tend to have poor outcomes with a few exceptions. They account for 10-15% of all non-Hodgkin lymphomas (NHL), and 20% of aggressive NHL. There has been little change in the overall prognosis of T cell lymphomas over the last 2 decades. Most subtypes carry an inferior prognosis when compared to the B cell lymphomas, with a 5-year OS of 30%. Gene expression profiling and other molecular techniques has enabled a deeper understanding of these differences in the various subtypes as reflected in the latest 5th WHO and ICC classification of T cell lymphomas. It is becoming increasingly clear that therapeutic approaches that target specific cellular pathways are needed to improve the clinical outcomes of T cell lymphomas. This review will focus on nodal T cell lymphomas and describe novel treatments and their applicability to the various subtypes.

Insights from a patient with chronic lymphocytic leukemia complicating ALK+ anaplastic large cell lymphoma

Chronic lymphocytic leukemia (CLL) that transforms into a more aggressive lymphoma has been termed Richter syndrome (RS). CLL with T-cell neoplasia is rarely reported; those with ALK⁺ anaplastic large cell lymphoma (ALCL) are also exceedingly rarely reported. A 63-year-old woman from the south of China presented with generalized lymphadenectasis and fever; she already had a prior diagnosis of CLL 9 years ago. As per her current diagnosis, it was CLL with ALK⁺ ALCL. The two-lymph node and bone marrow biopsies presented two types of cellular groups: i) left cervical lymph node biopsy suggested CLL (Ki67: 10%), along with bone marrow biopsy exhibited enhancement of the small lymphocytes (30%) with scant cytoplasm, round or irregular cell nuclei, and massive amounts of chromatin. Large cells (< 1%) that expressed CD30 and ALK were visible; The results of immunohistochemistry were as follows: CD20 (weak positive); PAX5 (positive); CD23 and CD5 (weak positive); and CD3, CD10, and CyclinD1 (negative); ii) left supraclavicular lymph node biopsy suggested ALK⁺ ALCL (Ki67: 70%). The final diagnosis was CLL with ALCL. The mechanisms of this condition are not fully understood, which might be associated with chronic stimulation of T cells by CLL cells along with immune dysfunction.

Immunohistochemical Approach to Genetic Subtyping of Anaplastic Large Cell Lymphoma

Anaplastic large cell lymphoma (ALCL) can be classified genetically based on rearrangements (R) of the ALK , TP63 , and/or DUSP22 genes. ALK- R defines a specific entity, ALK-positive ALCL, while DUSP22- R and TP63- R define subgroups of ALK-negative ALCLs with distinct clinicopathologic features. ALK -R and TP63 -R produce oncogenic fusion proteins that can be detected by immunohistochemistry. ALK immunohistochemistry is an excellent surrogate for ALK- R and screening with p63 immunohistochemistry excludes TP63- R in two third of ALCLs. In contrast, DUSP22 -R does not produce a fusion protein and its identification requires fluorescence in situ hybridization. However, DUSP22- R ALCL has a characteristic phenotype including negativity for cytotoxic markers and phospho-STAT3 Y705 . Recently, we also identified overexpression of the LEF1 transcription factor in DUSP22- R ALCL. Here, we sought to validate this finding and examine models for predicting DUSP22- R using immunohistochemistry for LEF1 and TIA1 or phospho-STAT3 Y705 . We evaluated these 3 markers in our original discovery cohort (n=45) and in an independent validation cohort (n=46) of ALCLs. The correlation between DUSP22- R and LEF1 expression replicated strongly in the validation cohort ( P <0.0001). In addition, we identified and validated a strategy using LEF1 and TIA1 immunohistochemistry that predicted DUSP22- R with positive and negative predictive values of 100% after exclusion of indeterminate cases and would eliminate the need for fluorescence in situ hybridization in 65% of ALK-negative ALCLs. This approach had similar results in identifying DUSP22- R in the related condition, lymphomatoid papulosis. Together with previous data, these findings support a 4-marker immunohistochemistry algorithm using ALK, LEF1, TIA1, and p63 for genetic subtyping of ALCL.

FDA approval summary: Crizotinib for pediatric and young adult patients with relapsed or refractory systemic anaplastic large cell lymphoma

In January 2021, the U.S. Food and Drug Administration (FDA) approved crizotinib for pediatric patients 1 year and older and young adults with relapsed or refractory systemic anaplastic large cell lymphoma (sALCL). This is the first approval for pediatric sALCL. Approval was based on a single-arm trial of crizotinib monotherapy that included 26 patients, aged 1-20 years, with previously treated sALCL. Efficacy was based on centrally assessed objective response rate (88%) and duration of response. Herein, we highlight unique aspects of the regulatory review, including extension of the indication to young adults, postmarketing safety, and dose optimization strategies.

A Right Atrial Mass with Fever and Cutaneous Nodules

Primary cardiac tumors, although exceedingly rare, should be considered in the differential diagnosis during workup of any cardiac mass. Extranodal cardiac lymphomas have a natural aggressive course due to delayed diagnosis. We present a 71-year-old male with a dual-chamber pacemaker who presented with fevers and new cutaneous nodules. He was found to have a right atrial primary anaplastic large-cell lymphoma and had a complete metabolic response after chemotherapy. Our case highlights the importance of a multimodality approach in the diagnosis of cardiac tumors and during follow-up after treatment.

Primary ALK-Negative TP63-Rearranged Anaplastic Large Cell Lymphoma in the Bladder: Potential for Misdiagnosis

A 76-year-old gentleman presented with persistent lower urinary tract symptoms. Multiple biopsies, radiological correlation and ancillary studies were required to achieve a diagnosis. The main differential diagnoses lies between urothelial carcinoma and anaplastic large cell lymphoma (ALCL), both of which are known to be positive for p63 and GATA3. An accurate diagnosis is crucial as the management is significantly different. To avoid misdiagnosis a comprehensive immunohistochemistry panel is necessary. Primary bladder lymphomas are rare. Our case represents the first case of primary ALK-negative TP63-rearranged ALCL. We reviewed the literature and discussed the potential pitfalls for misdiagnosis.

A rare presentation of anaplastic large cell lymphoma as a cavitary pulmonary mass with hypercalcemia

Cavitary lung lesions found on chest imaging may point to various diseases. These lesions may be caused by numerous etiologies, such as infection, inflammatory diseases, or malignancy. Thus, its etiology may be challenging to differentiate using imaging alone. Differential diagnoses are created using a combination of clinical symptoms, medical history, laboratory results, and physical examination. Primary pulmonary lymphoma and anaplastic large cell lymphoma (ALCL) are rare differentials. Here, we report a case of ALCL that initially presented with back pain, intermittent fever, hemoptysis, hypercalcemia, and bilateral multiple cavitary lung nodules. Because a cavitary pulmonary mass with sustained hypercalcemia is commonly seen in patients with squamous cell carcinomas or pulmonary tuberculosis, patients with ALCL may be misdiagnosed and undergo delayed treatment. This study highlights that ALCL should be considered in patients presenting with a cavitary pulmonary mass and hypercalcemia.

T-cell-derived Hodgkin lymphoma has motility characteristics intermediate between Hodgkin and anaplastic large cell lymphoma

Classic Hodgkin lymphoma (cHL) is usually characterized by a low tumour cell content, derived from crippled germinal centre B cells. Rare cases have been described in which the tumour cells show clonal T-cell receptor rearrangements. From a clinicopathological perspective, it is unclear if these cases should be classified as cHL or anaplastic large T-cell lymphoma (ALCL). Since we recently observed differences in the motility of ALCL and cHL tumour cells, here, we aimed to obtain a better understanding of T-cell-derived cHL by investigating their global proteomic profiles and their motility. In a proteomics analysis, when only motility-associated proteins were regarded, T-cell-derived cHL cell lines showed the highest similarity to ALK^- ALCL cell lines. In contrast, T-cell-derived cHL cell lines presented a very low overall motility, similar to that observed in conventional cHL. Whereas all ALCL cell lines, as well as T-cell-derived cHL, predominantly presented an amoeboid migration pattern with uropod at the rear, conventional cHL never presented with uropods. The migration of ALCL cell lines was strongly impaired upon application of different inhibitors. This effect was less pronounced in cHL cell lines and almost invisible in T-cell-derived cHL. In summary, our cell line-derived data suggest that based on proteomics and migration behaviour, T-cell-derived cHL is a neoplasm that shares features with both cHL and ALCL and is not an ALCL with low tumour cell content. Complementary clinical studies on this lymphoma are warranted.

Lymphoma versus Carcinoma and Other Collaborations

David Mason started his research career at a time when lymphoma diagnosis was based primarily on cellular morphology, clinical symptoms and special cytochemical stains using formalin fixed tissue sections. There were occasions, however, where the morphology was unhelpful, such as in the case of anaplastic or poorly differentiated tumours, where a distinction between lymphoma and a non-haematopoietic tumour was often problematical. Accurate diagnosis became even more important with the developments in the clinical staging of lymphoma and the availability of more effective treatments. One way forward to improve diagnosis was to use immunohistochemistry to study the antigens expressed by the tumor cells.

Systemic Anaplastic Large T-Cell Lymphoma with Initial Presentation of Dysuria in a Dog

A 6-year-old spayed female Akita Dog had dysuria, severe urinary retention and miliary masses in the vagina. Computed tomography revealed a mass at the urethrovaginal junction. The dog died 2 months after initial presentation. At necropsy, the urethrovaginal mass was greyish‒white, solid and 9 × 6 × 6 cm in size with circumferential thickening of the urethral wall. Multiple whitish nodules were seen in the visceral organs and skin. Histopathologically, the urethrovaginal mass comprised a diffuse population of medium-sized to large round neoplastic cells with ovoid to bean-shaped nuclei and eosinophilic cytoplasm. Aberrantly large neoplastic cells with eccentric, horseshoe-shaped or irregularly-shaped nuclei and abundant eosinophilic cytoplasm resembled 'hallmark cells' of human anaplastic large cell lymphoma. Similar neoplastic lesions were present in all the grossly visible masses. Neoplastic cells were diffusely immunopositive for CD3 and occasionally for CD30 and granzyme B. On the basis of the clinical, pathological and immunohistochemical findings, the case was diagnosed as systemic anaplastic large cell lymphoma arising from the lower urinary tract.

Resistance to Targeted Agents Used to Treat Paediatric ALK-Positive ALCL

Simple Summary

In general, the non-Hodgkin lymphoma (NHL), anaplastic large cell lymphoma (ALCL) diagnosed in childhood has a good survival outcome when treated with multi-agent chemotherapy. However, side effects of treatment are common, and outcomes are poorer after relapse, which occurs in up to 30% of cases. New drugs are required that are more effective and have fewer side effects. Targeted therapies are potential solutions to these problems, however, the development of resistance may limit their impact. This review summarises the potential resistance mechanisms to these targeted therapies.

Abstract

Non-Hodgkin lymphoma (NHL) is the third most common malignancy diagnosed in children. The vast majority of paediatric NHL are either Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL), anaplastic large cell lymphoma (ALCL), or lymphoblastic lymphoma (LL). Multi-agent chemotherapy is used to treat all of these types of NHL, and survival is over 90% but the chemotherapy regimens are intensive, and outcomes are generally poor if relapse occurs. Therefore, targeted therapies are of interest as potential solutions to these problems. However, the major problem with all targeted agents is the development of resistance. Mechanisms of resistance are not well understood, but increased knowledge will facilitate optimal management strategies through improving our understanding of when to select each targeted agent, and when a combinatorial approach may be helpful. This review summarises currently available knowledge regarding resistance to targeted therapies used in paediatric anaplastic lymphoma kinase (ALK)-positive ALCL. Specifically, we outline where gaps in knowledge exist, and further investigation is required in order to find a solution to the clinical problem of drug resistance in ALCL.

Crizotinib and ceritinib trigger immunogenic cell death via on-target effects

Immunogenic cell death (ICD) has initially been discovered in the context of chemotherapy. High-dose crizotinib also stimulates ICD, as we described for non-small cell lung cancer lacking activating chromosomal aberrations of ALK or ROS1, the usual targets of crizotinib, indicating that crizotinib may act through off-target effects. However, we found that low-dose of ALK inhibitors, crizotinib and ceritinib, may stimulate ICD in anaplastic large cell lymphoma, in which ALK is activated due to a chromosomal translocation, suggesting on target ICD-promoting effects.

New Data on the Epidemiology of Breast Implant-Associated Anaplastic Large Cell Lymphoma

OBJECTIVE

This study aimed to illustrate the epidemiological situation of breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) by focusing on the changes published after 2019 and particularly the new approaches of cosmetic and reconstructive breast surgery.

MATERIALS AND METHODS

Article search was performed from January 2019 to date using the PubMed database. Fourteen articles were included in the qualitative evaluation of international data. Moreover, the latest reports regarding the total number of BIA-ALCL cases and number of deaths were identified.

RESULTS

Estimates of the risk and incidence have increased significantly recently, affecting 1 in every 2,969 women with breast implants and 1 in 355 patients with textured implants after breast reconstruction. The average exposure time to diagnosis was 8 (range: 0-34) years. Approximately 80% of BIA-ALCL cases were diagnosed at IA-IIA stages, for which the treatment was breast implant removal, full capsulectomy, and excision of all suspected lymph nodes. Globally, at least 949 cases were reported to date.

CONCLUSION

At present, BIA-ALCL is an emerging pathology of interest. Data collection initiated since 2016 through different case registration databases is essential to ensure surveillance and to continue to increase the number of studies on this recently discovered pathology.

Clinical Features and Prognostic Factors for Primary Anaplastic Large Cell Lymphoma of the Central Nervous System: A Systematic Review

Simple Summary

Primary anaplastic large cell lymphoma (ALCL) of the central nervous system (CNS) is a subtype of primary central nervous system lymphoma (PCNSL). ALCL is divided into anaplastic lymphoma kinase (ALK)-positive ALCL and ALK-negative ALCL, according to ALK expression. ALK-positive cancers tend to develop at a younger age and tend to have a better prognosis. Almost all past articles on primary ALCL of the CNS have been case reports and there have been no randomized trials or cohort studies on this subject. We thus performed a systematic review of primary ALCL of the CNS. According to the author’s survey, 36 case reports have been published in English-language journals. In this paper, we have summarized the clinical features and prognostic factors for primary ALCL of the CNS based on previous studies.

Abstract

Primary anaplastic large cell lymphoma (ALCL) of the central nervous system (CNS) is a subtype of primary CNS lymphoma (PCNSL). There are very few comprehensive reports on this extremely rare tumor. Therefore, it is necessary to investigate the clinical features and prognostic factors for primary ALCL of the CNS. We performed a systematic review of the published literature. Past cases were comprehensively searched using PubMed, Cochrane Library, and Web of Science. Clinical information, such as age, sex, anaplastic lymphoma kinase (ALK) status, lesion sites, treatment methods, and survivorship were extracted. Thirty-nine cases with information on ALK status and treatment course were identified. The average observation period was 13 months, and the overall 2-year survival rate was 58%. Univariate analyses showed a statistically significantly better prognosis among patients < 40 years of age (p = 0.039, HR 0.32 (0.11–0.95)) and in relation to ALK positivity (p = 0.010, HR 0.24 (0.08–0.71) and methotrexate treatment (p = 0.003, HR 0.17 (0.05–0.56)). Because of the sparsity of cases, it is necessary to accumulate cases in order to perform more detailed analyses.

Cytokines, Genetic Lesions and Signaling Pathways in Anaplastic Large Cell Lymphomas

ALCL is a tumor of activated T cells and possibly innate lymphoid cells with several subtypes according to clinical presentation and genetic lesions. On one hand, the expression of transcription factors and cytokine receptors triggers signaling pathways. On the other hand, ALCL tumor cells also produce many proteins including chemokines, cytokines and growth factors that affect patient symptoms. Examples are accumulation of granulocytes stimulated by IL-8, IL-17, IL-9 and IL-13; epidermal hyperplasia and psoriasis-like skin lesions due to IL-22; and fever and weight loss in response to IL-6 and IFN-γ. In this review, we focus on the biology of the main ALCL subtypes as the identification of signaling pathways and ALCL-derived cytokines offers opportunities for targeted therapies.

Children with lymphoma presenting with hemophagocytic lymphohistiocytosis

BACKGROUND

< 7b > Hemophagocytic lymphohistiocytosis (HLH) may precede malignancy, in particular lymphomas and leukemias. However, the causative factors, appropriate treatment and the prognosis of this association is not established.

CASE

Herein, we present two patients, one with nodular sclerosing Hodgkin lymphoma (HL) and concomitant Epstein-Barr virus (EBV) infection, and the other with anaplastic large cell lymphoma (ALCL), presented as malignancy associated HLH.

CONCLUSION

In our patients, malignancy directed therapy was sufficient to treat HLH symptoms both at presentation and at recurrence in the second patient.

Diagnosis of anaplastic lymphoma kinase-negative anaplastic large cell lymphoma on pleural fluid cytology

ALK-negative anaplastic large cell lymphoma (ALCL) is an aggressive non-Hodgkin T-cell lymphoma. Compared to ALK-positive ALCL, patients with ALK-negative ALCL typically are older, present with nodal disease, and have lower survival rates. We report a unique presentation of ALK-negative ALCL in a pleural fluid. Cell block preparation enabled both confirmation of the diagnosis via immunohistochemical staining and gene rearrangement testing for prognostic information.

The Challenges of Crizotinib Treatment in a Child With Anaplastic Large Cell Lymphoma

Survival in cases involving childhood malignancy is reaching nearly 80% in high-income countries, yet cancer remains one of the leading disease-related causes of death in children. In adult oncology the role of targeted therapies is established, but information regarding the use of these therapies in children is limited, largely because targeted therapies were developed in the context of adult pathologies. The few pediatric reports regarding crizotinib, an anaplastic lymphoma kinase (ALK) inhibitor, seem promising. This case of an 8-year-old male with an ALK-positive anaplastic large cell lymphoma highlights the challenges of treating children with crizotinib. Our experience with crizotinib was more challenging than described in the limited pediatric reports. Not only was the tumor response poorer than described in the reports, but a substantial amount of side-effects and practical difficulties, such as the method of administration and dosing, made management challenging. Many challenges for the use of targeted therapy in pediatric care currently persist. The limited research in pediatric populations leaves uncertainty regarding efficacy and short- and long-term side effects as well as practical difficulties. Despite a clear underlying biological rationale for certain targeted therapies, their contribution toward improving the outcome of childhood cancer remains largely unclear.

Immunophenotypic shifts during minimal residual evaluation in a case of leukemic form of anaplastic large cell lymphoma ALK

BACKGROUND

This study aims to describe immunophenotypic explorations at diagnosis and follow up of a pediatric patient with leukemic phase of ALK+ anaplastic large cell lymphoma (ALCL) by multiparametric flow cytometry (MFC).

CASE

An 8-color MFC combination of antibodies allowed to identify neoplastic cells in concentrations until 0.02% during minimal residual disease (MRD) monitoring. Immunophenotypic shifts occurred in key markers as CD30, CD7, CD2, and CD5, however neoplastic cells were clearly discriminated from normal populations.

CONCLUSION

MFC can be a useful tool for ALCL diagnosis and MRD monitoring and may support therapeutic decisions.

Evolution of 18F-FDG Uptake as a Pitfall of Image Diagnosis for Systemic Anaplastic Large Cell Lymphoma

In most patients, systemic anaplastic large cell lymphoma (sALCL) is an ¹⁸F-FDG-avid tumor. Both ALK-positive and ALK-negative tumors can be evaluated by PET scans as both tumor types uptake ¹⁸F-FDG in PET. The PET scan is also valuable in predicting prognosis during and after the treatment course. The evolution of ¹⁸F-FDG uptake in patients with sALCL has not been reported. For tumors lacking ¹⁸F-FDG uptake, there is a diagnostic pitfall of underestimating the cancer stage and misjudgment of metastases. In the present case, the PET scan results were negative at diagnosis but disseminated ¹⁸F-FDG avid lesions were found at relapse. Biopsy of bone marrow and lymph nodes revealed the pathological features were identical to the original tumor at the time of diagnosis. In the wake of such evolutional change, physicians dealing with sALCL should be cautious in interpretation of PET/CT scans.

Primary anaplastic large cell lymphoma of caecum and ascending colon

Lymphomas are hematological malignancies with a wide variety of histological subtypes, varied clinical manifestations and behaviour and have a wide range of organ involvement. About 40 per cent of lymphomas are extra nodal. The most common extra nodal site is gastrointestinal tract (GIT). In the GIT, stomach is the most common organ involved accounting for 50-60 per cent of the lesions. Colorectal lymphomas are rare and account for 15-20 per cent of GIT lymphomas. They constitute 1 per cent of colorectal malignancies. Most common histological type of lymphoma involving GIT is diffuse large B-cell lymphoma, followed by MALT lymphoma; T-cell lymphomas are very rare and have an incidence of 3 per cent of Non Hodgkins Lymphoma (NHL). We report a case of anaplastic large cell lymphoma in the caecum and ascending colon with review of literature.