Proteomic Profiling Differentiates Lymphoma Patients with and without Concurrent Myeloproliferative Neoplasia.

Myeloproliferative neoplasia (MPN) and lymphoma are regarded as distinct diseases with different pathogeneses. However, patients that are diagnosed with both malignancies occur more frequently in the population than expected. This has led to the hypothesis that the two malignancies may, in some cases, be pathogenetically related. Using a mass spectrometry-based proteomic approach, we show that pre-treatment lymphoma samples from patients with both MPN and lymphoma, either angioimmunoblastic T-cell lymphoma (MPN-AITL) or diffuse large B-cell lymphoma (MPN-DLBCL), show differences in protein expression compared with reference AITL or DLBCL samples from patients without MPN. A distinct clustering of samples from patients with and without MPN was evident for both AITL and DLBCL. Regarding MPN-AITL, a pathway analysis revealed disturbances of cellular respiration as well as oxidative metabolism, and an immunohistochemical evaluation further demonstrated the differential expression of citrate synthase and DNAJA2 protein (p = 0.007 and p = 0.015). Interestingly, IDH2 protein also showed differential expression in the MPN-AITL patients, which contributes to the growing evidence of this protein's role in both myeloid neoplasia and AITL. In MPN-DLBCL, the disturbed pathways included a significant downregulation of protein synthesis as well as a perturbation of signal transduction. These results imply an underlying disturbance of tumor molecular biology, and in turn an alternative pathogenesis for tumors in these patients with both myeloid and lymphoid malignancies.

Coexisting BRAF-Mutated Langerhans Cell Histiocytosis and Primary Myelofibrosis with Shared JAK2 Mutation.

Langerhans cell histiocytosis (LCH) is an infrequent disease, characterized by oligoclonal proliferation of immature myeloid-derived cells. However, the exact pathogenesis remains unknown. In rare cases, LCH is present in patients with concomitant myeloid proliferative neoplasms. Here, we describe a 69-year-old male, who presented with a maculopapular rash covering truncus, face, and scalp. A cutaneous ulcerating lesion on the right cheek led to a biopsy showing LCH. Lesional cells were BRAF V600E and JAK2 V617F mutated. A bone marrow aspirate showed no infiltration of Langerhans cells, but alterations consistent with primary myelofibrosis (PMF) and a polymerase chain reaction test were positive for JAK2 V617F. Our case highlights an uncommon condition of two hematological malignancies present in the same patient. The identification of the BRAF V600E mutation supports previous findings of this mutation in LCH. Interestingly, a JAK2 V617F mutation was found in both LCH and PMF cells, indicating a possible clonal relationship between the two malignancies.

Reproducing the molecular subclassification of peripheral T-cell lymphoma-NOS by immunohistochemistry.

Peripheral T-cell lymphoma (PTCL) is a heterogeneous group of mature T-cell malignancies; approximately one-third of cases are designated as PTCL-not otherwise specified (PTCL-NOS). Using gene-expression profiling (GEP), we have previously defined 2 major molecular subtypes of PTCL-NOS, PTCL-GATA3 and PTCL-TBX21, which have distinct biological differences in oncogenic pathways and prognosis. In the current study, we generated an immunohistochemistry (IHC) algorithm to identify the 2 subtypes in paraffin tissue using antibodies to key transcriptional factors (GATA3 and TBX21) and their target proteins (CCR4 and CXCR3). In a training cohort of 49 cases of PTCL-NOS with corresponding GEP data, the 2 subtypes identified by the IHC algorithm matched the GEP results with high sensitivity (85%) and showed a significant difference in overall survival (OS) (P = .03). The IHC algorithm classification showed high interobserver reproducibility among pathologists and was validated in a second PTCL-NOS cohort (n = 124), where a significant difference in OS between the PTCL-GATA3 and PTCL-TBX21 subtypes was confirmed (P = .003). In multivariate analysis, a high International Prognostic Index score (3-5) and the PTCL-GATA3 subtype identified by IHC were independent adverse predictors of OS (P = .0015). Additionally, the 2 IHC-defined subtypes were significantly associated with distinct morphological features (P < .001), and there was a significant enrichment of an activated CD8+ cytotoxic phenotype in the PTCL-TBX21 subtype (P = .03). The IHC algorithm will aid in identifying the 2 subtypes in clinical practice, which will aid the future clinical management of patients and facilitate risk stratification in clinical trials.

Evaluation of clinical trial eligibility and prognostic indices in a population-based cohort of systemic peripheral T-cell lymphomas from the Danish Lymphoma Registry.

Clinical trials (CTs) are needed to improve the outcome for peripheral T-cell lymphomas (PTCL), and accrual into CTs is one of the main recommendations in international treatment guidelines. The use of risk-adapted strategies has been suggested as a way to optimize treatment outcome in PTCL. The aim of the present study was to evaluate CT eligibility and selected prognostic indices in a population-based PTCL cohort of 481 PTCL patients identified from the Danish Lymphoma Registry in the period 2000-2010. According to five predefined parameters (age, performance status, P-creatinine, P-ALAT and measurable tumour lesion), patients were subdivided into four groups: 'younger fit', 'elderly fit', 'frail' and 'not CT eligible'. International prognostic index (IPI), prognostic index for T-cell lymphoma (PIT) and anaplastic lymphoma kinase (ALK) protein expression were tested at subtype-specific level. Overall, 41% of the patients were considered eligible for interventional CTs implicating curatively intended multiagent chemotherapy, including, if considered appropriate, consolidating stem cell transplantation (SCT), as part of the upfront management strategy. Moreover, 28% was elderly fit and eligible for interventional CT, including those with SCT as part of the trial design. Approximately 7% were defined as 'too frail' for aggressive treatment schedules, whereas 24% were deemed not to be eligible for any CT. Both overall and progression-free survivals were effectively predicted by IPI and PIT (p < 0.001). ALK-positive anaplastic large cell lymphoma patients were significantly younger (median age 40 vs. 62, p < 0.001) and had a better outcome than their ALK-negative counterparts (p < 0.001). However, ALK expression lost its prognostic significance when adjusting for age. In a population-based cohort of adult Caucasian PTCL patients, approximately half were eligible for multiagent chemotherapy with or without consolidating SCT. Both IPI and PIT are useful prognostic indices in all 'primary nodal' PTCL entities. The prognostic value of ALK protein expression in anaplastic large cell lymphoma is significantly downsized when adjusting for age.

Changing the paradigms of treatment in peripheral T-cell lymphoma: from biology to clinical practice.

Despite enormous advances in our understanding of aggressive lymphomas, it is clear that progress in the peripheral T-cell lymphomas (PTCL) has lagged well behind other B-cell malignancies. Although there are many reasons for this, the one commonly cited notes that the paradigms for diffuse large B-cell lymphoma (DLBCL) were merely applied to all patients with PTCL, the classic "one-size-fits-all" approach. Despite these challenges, progress is being made. Recently, the FDA has approved four drugs for patients with relapsed/refractory PTCL over the past 5 years, and if one counts the recent Japanese approval of the anti-CCR4 monoclonal antibody for patients with adult T-cell leukemia/lymphoma, five drugs have been approved worldwide. These efforts have led to the initiation of no fewer than four randomized clinical studies exploring the integration of these new agents into standard CHOP (cyclophosphamide-Adriamycin-vincristine-prednisone)-based chemotherapy regimens for patients with newly diagnosed PTCL. In addition, a new wave of studies are exploring the merits of novel drug combinations in the disease, an effort to build on the obvious single-agent successes. What has emerged most recently is the recognition that the PTCL may be a disease-characterized by epigenetic dysregulation, which may help explain its sensitivity to histone deacetylase (HDAC) inhibitors, and open the door for even more creative combination approaches. Nonetheless, advances made over a relatively short period of time are changing how we now view these diseases and, hopefully, have poised us to finally improve its prognosis. See all articles in this CCR Focus section, "Paradigm Shifts in Lymphoma."