Treatment of T-cell non-hodgkin’ lymphoma

Tumorous formation of the forehead

T‑cell non-Hodgkin's lymphoma (NHL) represents approximately 10% to 15% of all lymphomas in Western countries. We present the case of a 16-year-old girl with nodular erosive tumor formation on the forehead within the previous 3-4 months and clinical evidence of cervical and submandibular lymphadenopathy in parallel. Tuberculosis verrucosa cutis, lupus vulgaris, cutaneous leishmaniasis, pyoderma faciale, sporotrichosis, infected insect bite, B‑cell lymphoma, and atypical acneiform eruption were considered in the differential diagnosis. The patient has undergone therapy with oral ciprofloxacin (2 × 250 mg/d) for 10 days and oral amoxicillin/clavulanic acid (2 × 1 g/d) for 7-8 days, followed by oral clindamycin (2 × 300 mg/d) and oral rifampicin (2 × 300mg/d) for 4 weeks-all without any improvement. Unfortunately, disease progression was observed. Histologic examination revealed evidence of peripheral T‑cell non-Hodgkin's lymphoma, and the subsequent immunohistochemical study confirmed the diagnosis, showing positive CD3 and CD4 expression and negative CD8, CD20, CD30, CD43, and ALK1 expression. Based on CT, lymph node involvement was found above and below the diaphragm, such that T‑cell lymphoma stage 4E was concluded. CHOEP chemotherapy treatment was initiated, with a favorable clinical outcome after the first cycle.

90Y-NM600 targeted radionuclide therapy induces immunologic memory in syngeneic models of T-cell Non-Hodgkin's Lymphoma

Finding improved therapeutic strategies against T-cell Non-Hodgkin’s Lymphoma (NHL) remains an unmet clinical need. We implemented a theranostic approach employing a tumor-targeting alkylphosphocholine (NM600) radiolabeled with ⁸⁶Y for positron emission tomography (PET) imaging and ⁹⁰Y for targeted radionuclide therapy (TRT) of T-cell NHL. PET imaging and biodistribution performed in mouse models of T-cell NHL showed in vivo selective tumor uptake and retention of ⁸⁶Y-NM600. An initial toxicity assessment examining complete blood counts, blood chemistry, and histopathology of major organs established ⁹⁰Y-NM600 safety. Mice bearing T-cell NHL tumors treated with ⁹⁰Y-NM600 experienced tumor growth inhibition, extended survival, and a high degree of cure with immune memory toward tumor reestablishment. ⁹⁰Y-NM600 treatment was also effective against disseminated tumors, improving survival and cure rates. Finally, we observed a key role for the adaptive immune system in potentiating a durable anti-tumor response to TRT, especially in the presence of microscopic disease.

Hernandez et al. show the effectiveness of ⁹⁰Y for targeted radionucleotide therapy of T-cell Non-Hodgkin’s Lymphoma (NHL). This study suggests that delivering radiation to all NHL disease sites elicits minimal toxicity and induces a memory T-cell response, inviting combination therapies with immune activating agents.

Autologous stem cell transplantation in first complete remission may not extend progression-free survival in patients with peripheral T cell lymphomas

Patients with peripheral T cell lymphomas (PTCL) generally have a poor prognosis when treated with conventional chemotherapy. Consolidation with autologous stem cell transplantation (ASCT) has been reported to improve progression-free survival. However, these studies have not compared consolidative ASCT with active observation in patients with PTCL achieving first complete remission (CR1) following induction chemotherapy. We conducted a retrospective analysis of PTCL patients treated at the University of Pennsylvania between 1/1/2007 and 12/31/2014. Patients with cutaneous T cell lymphoma, concurrent B cell lymphomas, and anaplastic lymphoma kinase-positive anaplastic large cell lymphoma (ALK-positive ALCL) were excluded from the study. We compared progression-free survival for patients who underwent ASCT in CR1 following CHOP-like induction regimens and patients who underwent active observation during CR1. 48 patients met all inclusion and exclusion criteria and underwent either active observation (28 patients) or consolidative ASCT (20 patients) in CR1. The 1-year cumulative incidence of relapse in the observation and ASCT groups was 50% (95% confidence interval [CI]: 30-67%) and 46% (95% CI: 23-67%), respectively (P = 0.55). Median progression-free survival in the observation and ASCT groups was 15.8 and 12.8 months, respectively (log rank, P = 0.79). Estimated 3-year progression-free survival in the observation and ASCT groups was 37 and 41%, respectively. In conclusion, for PTCL patients achieving CR1 following CHOP-like induction chemotherapy, ASCT does not appear to improve progression-free survival compared to active observation. This finding should be confirmed in a larger, prospective study. Am. J. Hematol. 91:672-676, 2016. © 2016 Wiley Periodicals, Inc.

The neutrophil-to-lymphocyte ratio is an independent prognostic factor in patients with peripheral T-cell lymphoma, unspecified

Peripheral T-cell lymphoma (PTCL) encompasses a group of rare and aggressive lymphomas. PTCL, unspecified (PTCLU) is the most common subtype of PTCL, and carries a poor prognosis. The International Prognostic Index (IPI) and the Prognostic Index for PTCLU (PIT) scoring systems are powerful risk-stratification tools in patients with PTCL. The aim of this study was to evaluate whether the neutrophil-to-lymphocyte ratio (NLR) is a prognostic factor in PTCLU. We retrospectively studied 83 patients with diagnosis of PTCLU. In the univariate analysis, NLR ≥ 4 was associated with worse overall survival (HR 3.96, 95% CI 1.92-8.17; p < 0.001). In the multivariate analysis, NLR ≥ 4 was independently associated with worse overall survival after adjustment for the PIT score (HR 4.30, 95% CI 1.90-9.69; p < 0.001), and for the IPI score (HR 2.60, 95% CI 1. 12-6.04; p = 0.03). Our study suggests the NLR could be helpful in refining the survival prognostication in patients with PTCLU.

A phase I/II trial of bortezomib combined concurrently with gemcitabine for relapsed or refractory DLBCL and peripheral T-cell lymphomas

There remains an unmet therapeutic need for patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) and peripheral T-cell lymphoma (PTCL). We conducted a phase I/II trial with bortezomib (dose-escalated to 1·6 mg/m(2) ) given concurrently with gemcitabine (800 mg/m(2) ) days 1 + 8 q21 d. Of 32 patients, 16 each had relapsed/refractory PTCL and DLBCL. Median prior therapies were 3 and 35% had failed transplant. Among the first 18 patients, 67% experienced grade 3/4 neutropenia and/or grade 3/4 thrombocytopenia resulting in repeated treatment delays (relative dose intensity: 46%). Thus, the study was amended to give bortezomib and gemcitabine days 1 + 15 q28 d, which resulted in markedly improved tolerability. Among all patients, the overall response rate (ORR) was 24% with 19% complete remission (CR; intent-to-treat (ITT) ORR 16%, CR 13%), which met criteria for futility. The ORR for DLBCL was 10% (CR 10%) vs. 36% for PTCL (CR 27%). Among 6 PTCL patients treated on the modified schedule, ORR by ITT was 50% (CR 30%). Altogether, concurrent bortezomib/gemcitabine given days 1 + 8 q21 d was not tolerable, while modification to a bi-monthly schedule allowed consistent treatment delivery. Whereas efficacy of this combination was low in heavily pre-treated DLBCL, there was a signal of activity in relapsed/refractory PTCL utilizing the modified schedule.

Gemcitabine-based combination regimen in patients with peripheral T-cell lymphoma

This study was conducted to evaluate the efficacy and safety of gemcitabine-based combination regimen in patients with peripheral T-cell lymphoma (PTCL). Between May 2007 and August 2011, 26 consecutive patients with PTCL were enrolled in this study. Of these 26 patients, histology was extranodal NK/T-cell lymphoma, nasal type in 14 (53.9 %), peripheral T-cell lymphoma, not otherwise specified in nine (34.6 %), anaplastic large cell lymphoma, ALK negative in three (11.5 %). The majority of patients had newly diagnosed (65.4 %) and advanced (80.8 %) diseases. Treatment regimen was DIMG (dexamethasone, ifosfamide, methotrexate, and gemcitabine) given to the first 6 patients, and GDP (gemcitabine, dexamethasone, and cisplatin) given to the remaining 20 patients. The median follow-up time was 25 (range 7-60) months. The overall response rate was 88.5 %. Twelve (46.2 %) patients achieved complete remission, 11 (42.3 %) patients achieved partial remission, and 1 (3.8 %) patient had stable disease (SD), two (7.7 %) patients had progressive diseases. The 1- and 2-year progression-free survival rates were 58.7 and 45.9 %, while 1- and 2-year overall survival rates for all patients were 80.6 and 63.7 %, respectively. Adverse events included grade 3 or 4 neutropenia (35.0 %) and thrombocytopenia (15.0 %) from patients treated with GDP. Grade 3 or 4 neutropenia and thrombocytopenia were 100.0 and 66.7 %, respectively, for patients who received DIMG regimen. Our study has demonstrated that the gemcitabine-based combination regimen, especially GDP regimen, is safe and well tolerated with promising clinical activity in patients with PTCLs.

Gemcitabine, oxaliplatin and dexamethasone as salvage treatment for elderly patients with refractory and relapsed peripheral T-cell lymphoma

The development of a more effective and less toxic salvage regimen remains a major challenge in elderly patients with relapsed and/or refractory peripheral T-cell lymphoma (PTCL). From April 2004 to May 2010, we used a new salvage regimen combining gemcitabine, oxaliplatin and dexamethasone (GemOD) in 24 elderly patients with relapsed (n = 11) or refractory (n = 13) PTCL unsuitable for high dose therapy. GemOD consisted of gemcitabine (1000 mg/m(2) on day 1), oxaliplatin (100 mg/m(2) on day 1) and dexamethasone (20 mg/day from day 1 to day 4), which was given every 3 weeks. Patients were scheduled to receive up to six courses of GemOD therapy unless there was evidence of progressive disease. The median number of GemOD courses delivered was four (range 3-6). After three courses of GemOD, the overall response rate (ORR) was 38%, with two complete responses (CRs) and seven partial responses (PRs). Among 11 patients who received three additional planned courses of therapy, there were three CRs and three PRs, for an ORR of 25% after complete treatment as per the study protocol. With a median follow-up of 18 months, the median overall survival (OS) and event-free survival (EFS) reached 14 and 10 months, respectively. Hematologic and non-hematologic toxicities were moderate in all patients. We conclude that the GemOD regimen can be administered safely and effectively in elderly patients with relapsed and refractory PTCL who are ineligible for high dose chemotherapy with stem cell transplant.

Diagnostic Impact of Molecular Lineage Analysis on Paraffin-Embedded Tissue in Hematolymphoid Neoplasia Reclassified by Current WHO Criteria

BACKGROUND AND OBJECTIVE

By current WHO criteria, most - though not all - cases of hematolymphoid neoplasm can be diagnosed immunomorphologically, diminishing the role of molecular tests for lymphoid antigen receptor clonality in lymphoma diagnosis. Hence, our objective was to glean immunomorphological and molecular correlates from hematolymphoid neoplasms that had remained unresolvable without diagnostic molecular input.

METHODS

Thirty-five such cases were reviewed histologically and with standard immunoperoxidases. In situ hybridization for Epstein-Barr virus (EBV)-encoded RNAs (EBER) was performed on selected cases. PCR amplification of genes encoding T-cell receptors (TcR) and immunoglobulin heavy chains (IgH) [TR and IGH genes, respectively] was performed on whole tissue in all cases, and on microdissected cells in two cases.

RESULTS

Twenty-five cases (71%) requiring diagnostic molecular genotyping had some form of peripheral T-cell lymphoma (PTCL). Twenty (80%) of these were complicated by a proliferation of B-lineage cells, either within the same tissue ('syntopic') as large B cells (LBC) or Reed-Sternberg (RS)-like cells (17 cases), florid lymphoid hyperplasia (two cases, one also with syntopic LBC) or monotypic plasma cells (one case), or at a separate ('metatopic') site as a B-cell lymphoma (two cases, one of which also had syntopic LBC) or Hodgkin lymphoma (HL; one case, also showing syntopic LBC). Fifteen (75%) of these 20 PTCLs with B-lineage proliferation yielded monoclonal TR gene rearrangements, and only two (10%) showed IGH monoclonality, which was transient in one case. Three (18%) of the PTCLs with LBC had originally been misinterpreted as some form of HL. Conversely, of the remaining cases, three of four (75%) that had been diagnosed initially as some form of large cell non-HL (NHL), including two of three that were called 'anaplastic', had to be revised to grade II/syncytial nodular sclerosing (NS) HL, yielding polyclonal TcRgamma gene (TRG) rearrangements, with one case, in addition, disclosing a biallelic clonal IGH gene rearrangement that excluded anaplastic large cell lymphoma.

DISCUSSION/CONCLUSION

Paradoxically, monoclonality of TR rather than IGH gene rearrangement may more often be detectable in a predominantly dispersed ('hodgkinoid'), large B-lineage cell proliferation, consistent with release from immune regulation in the milieu of impaired immunosurveillance within a PTCL. This is compounded by the difficulty in ascertaining clonal IGH gene rearrangements resulting from (1) poor consensus primer hybridization due to somatic hypermutations, and (2) 'dilution' in a T-cell-rich milieu. These same difficulties also account for the long-elusive identification of the RS cell lineage. Conversely, anaplastic lymphoma, which is of non-B lineage, may be mimicked by NSHL, which is of B lineage.

Clinicopathological Features and Outcomes of T- and NK-Cell Lymphomas in European Russia

With the introduction of the revised World Health Organization Classification of Tumors of Hematopoietic and Lymphoid Tissues in 2001, many patients had to be re-evaluated for the correct diagnosis of T- and NK-cell lymphomas. Because some T-cell malignancies are associated with poor outcome, it is important to identify subsets of patients that may benefit from novel or more intensive therapies. The purpose of this study was to determine, for the first time, the relative frequencies, pathological features and outcomes of patients with T- and NK-cell lymphomas in a predominantly Russian Slavic population. We identified 291 patients with a diagnosis of T- and NK-cell malignancies treated at our Center between 2000-2008. In applying the revised WHO classification, we confirmed the diagnosis and had complete clinical follow up and pathological information on 264 cases that were included in the analysis. We found some differences in frequency of several subsets as compared with previously published reports, including younger age of onset and relatively higher incidence of T-LGL in our patients. We also confirm that intensive treatment regimens of advanced stage PTCL and ALK—ALCL led to considerable improvement in response rates, but not in the overall survival.

Critical appraisal of pralatrexate in the management of difficult-to-treat peripheral T cell lymphoma

Aggressive T cell lymphomas are a subgroup of lymphomas with a particularly poor prognosis. This is especially true for patients with recurrent or refractory disease, who typically have limited response to salvage therapy and extremely poor overall survival. For this reason, there is a strong need to develop potentially active drugs for these malignancies. Pralatrexate is a novel antifolate designed to have high affinity for reduced folate carrier type 1. Preclinical and clinical studies have demonstrated that pralatrexate has significant activity against T cell lymphomas. The dose-limiting toxicity for pralatrexate is mucositis, which can be abrogated with folic acid and vitamin B12 supplementation. Pralatrexate is the first single agent approved for the treatment of patients with relapsed or refractory peripheral T cell lymphoma. This approval was based on an overall objective response rate observed in the pivotal study. The overall response rate was 29%, with a median duration of 10.1 months. This article reviews the biochemistry, preclinical experience, metabolism, and pharmacokinetics of pralatrexate, including the clinical experience with this agent in lymphoma. Future areas of development are now focused on identifying synergistic combinations of pralatrexate with other agents and the evaluation of predictive markers for clinical benefit.

T cell lymphoma presenting as esophageal obstruction and bronchoesophageal fistula

Background

The mediastinum is an uncommon location for presentation of peripheral T cell lymphoma. Esophageal involvement by non-Hodgkin’s lymphoma is extremely unusual. Although staging can be performed with routine imaging studies, surgical intervention is often required to ensure accurate histologic diagnosis of these lymphomas. Peripheral T cell lymphomas not otherwise specified are among the most aggressive non-Hodgkin lymphomas with often a poor response to conventional chemotherapy

Case Report

We report a case of a 63 year-old-man with an aggressive mediastinal T cell lymphoma presenting as esophageal obstruction and bronchoesophageal fistula. The patient was treated with a cyclophosphamide, vincristine, and prednisone (COP) regimen. Repeat computer tomography scan of the chest after chemotherapy noted a significant decrease in the cavitary lesion in the right paraesophageal region and right mediastinum. Bronchoscopy revealed a large opening in the posterior wall of the bronchus intermedius leading into the esophagus. A fistulogram was done which clearly demonstrated a fistulous tract between the lower esophagus and the right intermediate bronchus secondary to perforation from the lymphoma. The patient eventually underwent cervical esophagostomy and jejunostomy tube placement to correct the brochoesophageal fistula.

Conclusions

The mediastinum is an uncommon location for presentation of peripheral T cell lymphomas, and surgical intervention is often required to ensure accurate histological diagnosis of these lymphomas. In our patient, aggressive mediastinal T cell lymphoma presented as esophageal obstruction and bronchoesophageal fistula

Lymphoma classification: the quiet after the storm

The classification of malignant lymphomas remained controversial for over 30 years. The first scheme was proposed by Rappaport in the '60th and was based on incorrect histogenetic concepts. To overcome these limitations, several groups formulated new proposals in '70th. Among these two merited attention: the Lukes and Collins and the Kiel Classifications. They were based on the assumption that each lymphoma category might be related to a precise differentiation step of the lymphoid system, thus excluding any correlation with histiocytes, present on the Rappaport scheme. The Kiel Classification became very popular in Europe, while the one of Luke and Collins did not meet success in the United States (U.S.). In 1978, the National Cancer Institute proposed an international trial to compare the classifications used in Europe and U.S. The result was the genesis of the Working formulation, the tool for lymphoma classification in the U.S. up to the early '90th, but which was conversely rejected in Europe. In order to get over this lack of transatlantic communication, in 1994 the Revised European-American Lymphoma (REAL) Classification was proposed by the International Lymphoma Study Group. Its goal was to list "real" entities, each defined by the presence of homogeneous morphologic, phenotypic, cytogenetic, molecular, and clinical criteria, along with the possible recognition of its normal counterpart. The REAL Classification became the model for the WHO Classification of all haematopoietic tumours published in 2001. The present review aims to analyse future perspectives after the fourth edition of the WHO Classification released in 2008.

Peripheral T-cell lymphoma classification: the matter of cellular derivation

Peripheral T-cell lymphomas (PTCLs) represent approximately 12% of all non-Hodgkin's lymphomas in Western countries. They are quite heterogeneous as far as morphology and phenotype are concerned. Furthermore, until now, PTCLs could not be referred to specific normal counterparts, in contrast to B-cell-derived non-Hodgkin's lymphomas. In particular, in the last edition of the WHO classification of Tumors of the Hematopoietic and Lymphoid Tissues, for the majority of nodal PTCLs (including the not otherwise specified type and anaplastic large-cell lymphoma), the postulated cell of origin remained undefined. However, in the last few years, high-throughput genomic techniques, especially gene-expression profiling, have allowed us to better define the relationship between some entities and the different T-cell subpopulations. Consequently, it has become possible to clearly define, for example, the association between angioimmunoblastic T-cell lymphoma and T-follicular helper cells. In addition, within PTCLs/not otherwise specified, different subgroups were identified based on their similarity to different cellular counterparts, including T-helper, T-cytotoxic and T-follicular helper cells. In this article, based on their own experience as well as up-to-date literature, the authors revise the concept of PTCL classification by specially focusing on their cellular counterparts and discuss the possible clinical relevance of such an approach.

Prognostic markers in peripheral T-cell lymphoma

Based on their own experience and knowledge of the literature, the authors review the pathobiological characteristics of peripheral T-cell lymphomas (PTCLs), focusing on the available prognostic indicators. The International Prognostic Index (IPI), which is based on age, performance status, lactate dehydrogenase [LDH], stage, and extranodal involvement, appears to be efficient as a prognostic index for PTCLs, at least in part and especially for certain PTCL subtypes. However, it is not so satisfactory for the two commonest PTCLs, PTCL not otherwise specified (PTCL/NOS) and angioimmunoblastic T-cell lymphoma (AITL), for which novel scores, possibly based on the biologic features of the tumors, have been explored. An Italian cooperative group proposed a revision of the IPI for PTCL unspecified (PTCL-U), the Prognostic Index for PTCL-U (PIT), which includes age, performance status, LDH, and bone marrow involvement. The PIT apparently offered some advantages, but they were not confirmed in subsequent studies. A clinical-biological score (the Bologna score) was then proposed, including tumor proliferation and clinical features (age, LDH, and performance status). This score appears promising and offers the intriguing advantage of integrating biological and clinical elements, but independent validation on a large series is still warranted. More recently, gene expression profiling has been used to identify novel molecular prognostic factors. In particular, inactivation of the NFκB pathway, high expression of proliferation-associated genes, and cytotoxic molecular phenotype seem to be associated with a worse outcome. So far, however, none of these indicators has been validated in an independent series. Finally, various reports have dealt specifically with the prognostication of NK-derived tumors, including nasal and nasal-type lymphomas. Both the IPI and dedicated models have turned out to be of prognostic relevance for these tumors. In conclusion, although the IPI is somewhat effective for PTCL prognostication, novel scores that are more refined and possibly disease-specific are warranted. The validation process for several models, including clinical-pathological and molecular models, is now ongoing.

Intensified alemtuzumab-CHOP therapy for peripheral T-cell lymphoma

BACKGROUND

The prognosis of T-cell lymphoma is poor. To explore the addition of the monoclonal antibody alemtuzumab, we studied the efficacy and tolerability of an intensified alemtuzumab-chemotherapy combination for aggressive T-cell lymphoma in a phase II study by Dutch-Belgian Hemato-Oncology Group (HOVON).

PATIENTS AND METHODS

Patients (≤65 years) with newly diagnosed T-cell lymphoma received eight CHOP cycles (cyclophosphamide, doxorubicin, vincristine, prednisone) 2-weekly, each cycle with three doses of 30 mg alemtuzumab. Prophylaxis consisted of cotrimoxazole, fluconazole and valaciclovir. Cytomegalovirus (CMV) monitoring took place at least every fortnight.

RESULTS

Twenty patients from 10 centers, median age 50 years, were included. Eighty-five percent received six or more cycles. The overall response was 90% [12 complete remissions (CRs), 1 CR unconfirmed, 5 partial remissions]. Median duration of follow-up of patients still alive was 29 months (range 19-41 months). Median overall survival (OS) and event-free survival (EFS) were 27 and 10 months, with 55%/27% OS/EFS at 2 years. Adverse events consisted of neutropenic fever (n = 8) and CMV reactivation (n = 7), with one CMV disease. Three patients developed secondary Epstein-Barr virus (EBV)-related lymphoma, all after end of treatment.

CONCLUSIONS

Although intensified alemtuzumab-CHOP induces high responses, many patients relapse, and the scheme is associated with serious infection-related adverse events. EBV monitoring after end of treatment is required.

Gemcitabine as single agent in pretreated T-cell lymphoma patients: evaluation of the long-term outcome

BACKGROUND

Peripheral T-cell lymphoma unspecified (PTCLU) and mycosis fungoides (MF) often show resistance to conventional chemotherapy. Gemcitabine should be considered a suitable option. We report the long-term update of 39 pretreated T-cell lymphoma patients treated with gemcitabine.

PATIENTS AND METHODS

From May 1997 to September 2007, 39 pretreated MF and PTCLU patients received gemcitabine. Inclusion criteria were as follows: histologic diagnosis of MF or PTCLU; relapsed/refractory disease; age > or =18 years; and World Health Organization performance status of two or less. Nineteen patients had MF and 20 PTCLU. All patients with MF had a T3-T4, N0, and M0 disease and patients with PTCLU had stage III-IV disease. Gemcitabine was given on days 1, 8, and 15 on a 28-day schedule (1200 mg/m(2)/day) for a total of three to six cycles.

RESULTS

Overall response rate was 51% (20 of 39 patients); complete response (CR) and partial response (PR) rates were 23% (9 of 39 patients) and 28% (11 of 39 patients), respectively. Patients with MF had a CR rate of 16% and a PR rate of 32% compared with a CR rate of 30% and a PR rate of 25% of PTCLU patients. Among the CR patients, 7 of 9 are in continuous complete response with a variable disease-free interval (15-120 months).

CONCLUSION

In our experience, gemcitabine proved to be effective in pretreated MF and PTCLU patients, even in the long term.

Pralatrexate, a new hope for aggressive T-cell lymphomas?

Aggressive T-cell lymphomas represent a particularly poor-prognosis subgroup of lymphomas. This is especially true for patients with recurrent or refractory disease who typically have a limited response to salvage therapy and an extremely poor overall survival. There is thus a strong need to develop potentially active drugs for these malignancies. Pralatrexate is a novel antifolate designed to have high affinity for the reduced folate carrier type 1. Preclinical and clinical studies have demonstrated that pralatrexate has significant activity against T-cell lymphomas.The dose-limiting toxicity for pralatrexate is mucositis,which could be abrogated with folic acid and vitamin B12 supplementation. Pralatrexate is now being evaluated in phase II clinical trials for the treatment of peripheral T-cell lymphoma, and in a phase I/II trial in combination with gemcitabine for the treatment of non-Hodgkin's lymphoma. Because of the limited therapies available for aggressive T-cell lymphoma, pralatrexate could secure a niche for the treatment of this condition, provided on going clinical trials and future phase III trials confirm the efficacy of the drug.

F-18-fluoro-deoxy-glucose positron emission tomography in the assessment of peripheral T-cell lymphomas

F-18-fluoro-deoxy-glucose positron emission tomography (PET) is highly sensitive and specific in the imaging of B-cell lymphomas. In contrast, its utility in the diagnostic evaluation of T-cell lymphomas is less defined. In this article, we present our finding utilizing PET in peripheral T-cell lymphomas (PTCL). A retrospective review of patients who underwent PET examinations at our institution produced 24 PET examinations among patients with PTCL. A lesion-based analysis was undertaken to evaluate the diagnostic accuracy of PET in PTCL. PET findings were compared with a standard of reference and sensitivity, specificity, positive and negative predictive values were calculated. PET had an overall sensitivity of 86% and specificity of 100%. PET had high sensitivity (95%) at nodal and non-cutaneous extra-nodal sites and poor sensitivity (13%) at cutaneous sites. The mean SUV of abnormal foci in anaplastic large cell lymphoma was 11 mg/ml (range: 3 - 40), and PTCL-unclassified was 8 mg/ml (range: 1 - 23).

Results of a phase II study of 506U78 in cutaneous T-cell lymphoma and peripheral T-cell lymphoma: CALGB 59901

Nelarabine (compound 506U78), a novel purine nucleoside, is a soluble pro-drug of 9-beta-D-arabinofuranosylguanine (ara-G). Nelarabine is rapidly demethoxylated in blood by adenosine deaminase to ara-G. Pre-clinical and clinical studies have demonstrated the selective cytotoxicity of ara-G to T-lineage derived cells. CALGB Protocol 59901 was a Phase II study of nelarabine in patients with systemically untreated cutaneous T-cell lymphoma (CTCL) or refractory/relapsed systemic T-cell lymphoma (STCL). The objectives were to determine response rate, remission duration and safety profile associated with nelarabine given at 1.5 g m(-2) per day on days 1, 3 and 5 as an intravenous infusion every 21 days for a minimum of two cycles and to continue up to two cycles beyond CR up to a maximum of eight cycles. Nineteen patients were enrolled in the study: 11 CTCL and eight STCL patients. Grade 3 or 4 adverse events were documented in 50% and 28%, respectively. In particular, 33% of patients experienced Grade 3 or 4 neurologic toxicities. There were two partial remissions lasting 3 months and 5.5 months, respectively. Median event-free survival was 1.2 months and median overall survival was 3 months. Due to lack of efficacy and excessive toxicity, nelarabine is not recommended as monotherapy in adult patients with CTCL and STCL at this dose schedule.

Current status of older and new purine nucleoside analogues in the treatment of lymphoproliferative diseases

For the past few years more and more new cytotoxic agents active in the treatment of hematological malignancies have been synthesized and become available for either in vitro studies or clinical trials. Among them the class of antineoplastic drugs belonging to the purine nucleoside analogues group (PNAs) plays an important role. Three of them: pentostatin (DCF), cladribine (2-CdA) and fludarabine (FA) were approved by Food and Drug Administration (FDA) for the treatment of hematological malignancies. Recently three novel PNAs: clofarabine (CAFdA), nelarabine (ara-G) and forodesine (immucillin H, BCX-1777) have been synthesized and introduced into preclinical studies and clinical trials. These agents seem to be useful mainly for the treatment of human T-cell proliferative disorders and they are currently undergoing clinical trials in lymphoid malignancies. However, there are also several studies suggesting the role of these drugs in B-cell malignancies. This review will summarize current knowledge concerning the mechanism of action, pharmacologic properties, clinical activity and toxicity of PNAs accepted for use in clinical practice, as well as new agents available for clinical trials.

Peripheral T cell lymphoma, not otherwise specified: the stuff of genes, dreams and therapies

Peripheral T cell lymphomas (PTCL) account for about 12% of lymphoid tumours worldwide. Almost half show such morphological and molecular variability as to hamper any further classification, and to justify their inclusion in a waste-basket category termed “not otherwise specified (NOS)”. The latter term is used for neoplasms with aggressive presentation, poor response to therapy and dismal prognosis. In contrast to B cell lymphomas, PTCL have been the subject of only a limited number of studies to elucidate their pathobiology and identify novel pharmacological approaches. Herewith, the authors revise the most recent contributions on the subject based on the experience they have gained in the extensive application of microarray technologies. PTCL/NOS are characterised by erratic expression of T cell associated antigens, including CD4 and CD52, which have recently been proposed as targets for ad hoc immunotherapies. PTCL/NOS also show variable Ki-67 marking, with rates >80% heralding a worse prognosis. Gene expression profiling studies have revealed that PTCL/NOS derive from activated T lymphocytes, more often of the CD4+ type, and bear a signature composed of 155 genes and related products that play a pivotal role in cell signalling transduction, proliferation, apoptosis and matrix remodelling. This observation seems to pave the way for the use of innovative drugs such as tyrosine kinase and histone deacetylase inhibitors whose efficacy has been proven in PTCL primary cell cultures. Gene expression profiling also allows better distinction of PTCL/NOS from angioimmunoblastic T cell lymphoma, the latter being characterised by follicular T helper lymphocyte derivation and CXCL13, PD1 and vascular endothelial growth factor expression.

International peripheral T-cell and natural killer/T-cell lymphoma study: pathology findings and clinical outcomes

PURPOSE

Peripheral T-cell lymphoma (PTCL) and natural killer/T-cell lymphoma (NKTCL) are rare and heterogeneous forms of non-Hodgkin's lymphoma (NHL) that, in general, are associated with a poor clinical outcome.

PATIENTS AND METHODS

A cohort of 1,314 cases of PTCL and NKTCL was organized from 22 centers worldwide, consisting of patients with previously untreated PTCL or NKTCL who were diagnosed between 1990 and 2002. Tissue biopsies, immunophenotypic markers, molecular genetic studies, and clinical information from consecutive patients at each site were reviewed by panels of four expert hematopathologists and classified according to the WHO classification.

RESULTS

A diagnosis of PTCL or NKTCL was confirmed in 1,153 (87.8%) of the cases. The most common subtypes were PTCL not otherwise specified (NOS; 25.9%), angioimmunoblastic type (18.5%), NKTCL (10.4%), and adult T-cell leukemia/lymphoma (ATLL; 9.6%). Misclassification occurred in 10.4% of the cases including Hodgkin's lymphoma (3%), B-cell lymphoma (1.4%), unclassifiable lymphoma (2.8%), or a diagnosis other than lymphoma (2.3%). We found marked variation in the frequency of the various subtypes by geographic region. The use of an anthracycline-containing regimen was not associated with an improved outcome in PTCL-NOS or angioimmunoblastic type, but was associated with an improved outcome in anaplastic large-cell lymphoma, ALK positive.

CONCLUSION

The WHO classification is useful for defining subtypes of PTCL and NKTCL. However, expert hematopathology review is important for accurate diagnosis. The clinical outcome for patients with most of these lymphoma subtypes is poor with standard therapies, and novel agents and new modalities are needed to improve survival.

Marker expression in peripheral T-cell lymphoma: a proposed clinical-pathologic prognostic score

PURPOSE

Although peripheral T-cell lymphoma, unspecified (PTCL/U), is the most common T-cell tumor in Western countries, no study to date has been based on the application of a wide panel of markers to a large series of patients and assessed the impact of phenotype on survival. We evaluated the expression of 19 markers in 148 PTCLs/U and 45 PTCLs of the angioimmunoblastic type (AILD).

PATIENTS AND METHODS

The analysis was performed on tissue microarrays by immunohistochemistry and in situ hybridization. Clinical data were available in 93 PTCL/U patients, most of whom had been included in a previous study proposing a prognostic index (PIT).

RESULTS

An aberrant phenotype with frequent loss of CD5 and/or CD7 was typical for PTCLs, irrespective of whether they were U or AILD. Aberrantly expressed proteins rarely included CD20, CD15, and CD30. Positivity for Epstein-Barr virus-associated small RNAs and CD15 expression emerged as adverse prognostic factors. Among PTCLs/U, the proliferation-associated protein Ki-67 turned out to be prognostically relevant and was integrated in a new predictive score, incorporating age (> 60 years), high lactate dehydrogenase, poor performance status, and Ki-67 > or = 80%. This score was associated with the patient outcome (P < .0001) and was found to be more robust than PIT (P = .0043) in the present series.

CONCLUSION

Our retrospective analysis shows a wide range of protein expression in PTCLs and proposes a new prognostic index. The latter represents one of the first examples of mixed score (including patient- and tumor-specific factors) applied to malignant lymphomas and may be the basis for future prospective therapeutic trials.

Therapy of Peripheral T/NK Neoplasms

The mature T/natural killer (NK) lymphoma/leukemias represent 5–15% of all non-Hodgkin lymphoma. These diseases have a geographic variation, with more nodal disease in North America and Europe, including peripheral T cell lymphomas, unspecified, anaplastic large cell lymphoma, and angioimmunoblastic T cell lymphoma; and more extranodal disease in Asia due to Epstein-Barr virus–related nasal NK/T lymphoma and human T-cell leukemia virus (HTLV)-1–associated adult T cell leukemia/lymphoma. The prognosis in most peripheral T/NK neoplasms is poor, with 5-year survival less than 30%. Progress has been slow due to the rarity of the diseases, geographic variation, relative chemoresistance, and lack of randomized trials. There is no consensus about optimal therapy in T/NK neoplasms, and recommendations are based on anecdotal reports, small series, and phase II trials. In this review, topics include the question of CHOP as standard therapy, prognostic factors, disease-adapted therapy, novel approaches, monoclonal antibody therapy, and stem cell transplantation.

Therapy of Chronic Lymphocytic Leukaemia with Purine Nucleoside Analogues

Chronic lymphocytic leukaemia (CLL) is a neoplastic disease of unknown aetiology characterised by an absolute lymphocytosis in peripheral blood and bone marrow. The disease is diagnosed most commonly in the elderly with the median age at diagnosis being about 65 years. The purine nucleoside analogues (PNAs) fludarabine, cladribine (2-chlorodeoxyadenosine) and pentostatin (2'-deoxycoformycin) are highly active in CLL, both in previously treated and in refractory or relapsed patients. These three agents share similar chemical structures and mechanisms of action such as induction of apoptosis. However, they also exhibit significant differences, especially in their interactions with enzymes involved in adenosine and deoxyadenosine metabolism. Recent randomised studies suggest that fludarabine and cladribine have similar activity in CLL. However, clinical observations indicate the existence of cross-resistance between fludarabine and cladribine. Patients who received PNAs as their initial therapy and achieved long-lasting response can be successfully retreated with the same agent. PNAs administered in combination with other chemotherapeutic agents and/or monoclonal antibodies may produce higher response rates, including complete response (CR) or molecular CR, compared with PNAs alone or other treatment regimens. Management decisions are more difficult in elderly patients because of the apparent increase in toxicity of PNAs in this population. In elderly patients, we recommend chlorambucil as the first-line treatment, with PNAs in lower doses in refractory or relapsed patients. Myelosuppression and infections, including opportunistic varieties, are the most frequent adverse effects in patients with CLL treated with PNAs. Therefore, some investigators recommend routine antibacterial and antiviral prophylaxis during and after PNA treatment. This review presents current results and treatment strategies with the use of PNAs in CLL, especially in elderly patients.