Report of an international workshop to standardize baseline evaluation and response criteria for primary CNS lymphoma

YKL-40 and MMP-9 as serum markers for patients with primary central nervous system lymphoma

OBJECTIVE

To evaluate YKL-40 and MMP-9 proteins as tumor biomarkers in serum samples from patients with primary central nervous system lymphoma (PCNSL).

METHODS

In this prospective longitudinal study, serum samples from consecutive patients with histologically confirmed PCNSL were collected concurrently with magnetic resonance imaging (MRI) scans at multiple time points and were analyzed for levels of YKL-40 and MMP-9 by enzyme-linked immunosorbent assay. Marker levels were correlated to disease status and survival.

RESULTS

Forty-five patients with PCNSL were accrued. Median follow-up for survivors was 25 months, and 21 (47%) died during the study. A total of 230 serum samples were collected, and 93% had corresponding MRI scans. PCNSL patients without evidence of radiographic disease (29 patients, 131 samples) had significantly lower levels of serum YKL-40 and MMP-9 than patients with active tumor (n = 34 patients, 84 samples; p = 0.03 and 0.01, respectively). There was a significant inverse correlation between survival and doubling of the YKL-40 level (hazard ratio, 1.7; p = 0.01).

INTERPRETATION

In patients with PCNSL, serum levels of YKL-40 and MMP-9 are associated with radiographic disease status. Longitudinal increase in serum levels of YKL-40, but not MMP-9, predicts survival in patients with PCNSL.

An unusual case of primary anaplastic large cell central nervous system lymphoma: an 8-year success story

Primary central nervous system anaplastic large cell lymphoma (PCNS ALCL) is rare, with only three adult patients reported. We describe a patient with PCNS ALCL with the longest follow-up period so far reported. The patient was successfully treated with chemotherapy and radiotherapy. The patient is well, independent and in full-time employment and has no residual neurological deficit. He has normal mental status, has a full head of hair and has fathered a healthy child.

Immunochemotherapy with rituximab, methotrexate, procarbazine, and lomustine for primary CNS lymphoma (PCNSL) in the elderly

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is an aggressive extranodal non-Hodgkin lymphoma confined to the central nervous system. In this article, we report the results of a pilot trial adding rituximab to the established regimen consisting of methotrexate, procarbazine, and lomustine (R-MCP).

DESIGN AND METHODS

PCNSL patients ≥65 years without Karnofsky performance score (KPS) limit were included. R-MCP regimen consisted of rituximab (375 mg/m(2) i.v. on days -6, 1, 15, and 29), methotrexate (3 g/m(2) i.v., days 2, 16, and 30) followed by folinic rescue, procarbazine (60 mg/m(2) orally, days 2-11), and lomustine (110 mg/m(2) orally, day 2). A maximum of three 43-day cycles were applied. Primary end point was response to treatment obtained by magnetic resonance imaging. Secondary end points were overall survival (OS) and progression-free survival (PFS).

RESULTS

Twenty-eight patients were included (median age 75, median KPS 60%). Best documented response: complete remission in 18 of 28 (64%), partial remission in 5 of 28 (18%), stable disease in 1 of 28 (4%), and progressive disease in 2 of 28 (7%) patients. Response was not assessed in two patients. Two treatment-associated deaths were observed. After a median follow-up of 36 months, the 3-year PFS and OS was 31%.

CONCLUSION

R-MCP regimen is well tolerated and active in elderly patients with newly diagnosed PCNSL.

Primary central nervous system lymphoma

PURPOSE OF REVIEW

This review will summarize recent advances in the understanding and treatment of primary central nervous system lymphoma (PCNSL).

RECENT FINDINGS

The molecular and genetic characteristics that distinguish PCNSL are beginning to be elucidated. New tools such as flow cytometry and PET are improving the diagnosis and management of PCNSL. Although the current standard of care is high-dose methotrexate-based chemotherapy alone or in combination with whole brain radiotherapy, multiple questions remain regarding the optimal treatment of PCNSL, in general, and unusual variants of PCNSL.

SUMMARY

Although recent advances have improved our understanding of PCNSL, the need for additional collaborative research is critical.

Primary intramedullary histiocytic sarcoma

Intramedullary primary central nervous system lymphoma (PCNSL) is a rare central nervous system (CNS) malignancy affecting mostly the brain, but it may also involve the leptomeninges, eyes, and spinal cord. A 71-year-old woman presented with back pain and progressive unilateral lower extremity weakness owing to an intramedullary primary histiocytic sarcoma of the spine, a rare PCNSL subtype. To the authors' knowledge, this is the first case of an intramedullary PCNSL caused by histiocytic sarcoma.

Primary CNS lymphoma in children and adolescents: a descriptive analysis from the International Primary CNS Lymphoma Collaborative Group (IPCG)

PURPOSE

To describe the demographic and clinical features and outcomes for children and adolescents with primary CNS lymphoma (PCNSL).

EXPERIMENTAL DESIGN

A retrospective series of children and adolescents with PCNSL was assembled from 10 cancer centers in 3 countries.

RESULTS

Twenty-nine patients with a median age of 14 years were identified. Sixteen (55%) had Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 1 or greater. Frontline therapy consisted of chemotherapy only in 20 patients (69%), while 9 (31%) had chemotherapy plus cranial radiotherapy. Most patients received methotrexate (MTX)-based regimens. Overall response rate was 86% (complete remission 69%, partial remission 17%). The 2-year progression-free survival (PFS) and overall survival (OS) rates were 61% and 86%, respectively; the 3-year OS was 82%. Univariate analyses were conducted for age (≤ 14 vs. >14 years), PS (0 or 1 vs. >1), deep brain lesions, MTX dose, primary treatment with chemotherapy alone, intrathecal chemotherapy, and high-dose therapy. Primary treatment with chemotherapy alone was associated with better overall response rates with an odds ratio (OR) of 0.125 (P = 0.02). There was a marginally significant relationship between higher doses of MTX and response (OR = 1.5, P = 0.06). ECOG-PS of 0 to 1 was the only factor associated with better outcome with hazard ratios of 0.136 (P = 0.017) and 0.073 (P = 0.033) for PFS and OS, respectively.

CONCLUSION

This is the largest series collected of pediatric PCNSL. The outcome of children and adolescents seems to be better than in adults. PS of 0 to 1 is associated with better survival.

Identification of microRNAs in the cerebrospinal fluid as marker for primary diffuse large B-cell lymphoma of the central nervous system

The diagnosis of primary central nervous system lymphoma (PCNSL) depends on histopathology of brain biopsies, because disease markers in the cerebrospinal fluid (CSF) with sufficient diagnostic accuracy are not available yet. MicroRNAs (miRNAs) are regulatory RNA molecules that are deregulated in many disease types, including cancer. Recently, miRNAs have shown promise as markers for cancer diagnosis. In this study, we demonstrate that miRNAs are present in the CSF of patients with PCNSL. With a candidate approach and miRNA quantification by reverse transcription polymerase chain reaction, miRNAs with significant levels in the CSF of patients with PCNSL were identified. MiR-21, miR-19, and miR-92a levels in CSF collected from patients with PCNSL and from controls with inflammatory CNS disorders and other neurologic disorders indicated a significant diagnostic value of this method. Receiver-operating characteristic analyses showed area under the curves of 0.94, 0.98, and 0.97, respectively, for miR-21, miR-19, and miR-92a CSF levels in discriminating PCNSL from controls. More importantly, combined miRNA analyses resulted in an increased diagnostic accuracy with 95.7% sensitivity and 96.7% specificity. We also demonstrated a remarkable stability of miRNAs in the CSF. In conclusion, CSF miRNAs are potentially useful tools as novel noninvasive biomarker for the diagnosis of PCNSL.

Diagnosis of leptomeningeal disease in diffuse large B-cell lymphomas of the central nervous system by flow cytometry and cytopathology

Reliable detection of leptomeningeal disease has the potential of facilitating the diagnosis of central nervous system (CNS) lymphoma and is important for therapeutic considerations. Currently, the standard diagnostic procedure for the detection of lymphoma in the cerebrospinal fluid is cytopathology. To improve the limited specificity and sensitivity of cytopathology, flow cytometry has been suggested as an alternative. Here, we evaluated multi-parameter flow cytometry in combination with conventional cytopathology in cerebrospinal fluid (CSF) samples from 30 patients with primary CNS lymphoma and seven patients with secondary CNS lymphoma. Overall, in 11 of 37 (29.7%) patients with CNS lymphoma, lymphoma cells were detected in CSF by flow cytometry, while cytopathology was less sensitive displaying unequivocally malignant CSF cells in only seven of all 37 (18.9%) patients. Six (16.2%) patients showed cytopathological results suspicious of lymphoma; however, in only one of these patients, the diagnosis of CSF lymphoma cells could be confirmed by flow cytometry. In primary CNS lymphomas (PCNSL), seven of 30 (23.3%) patients were positive for CSF lymphoma cells in flow cytometry, in contrast to four (13.3%) patients with PCNSL with definitely positive cytopathology. In summary, our results suggest that multi-parameter flow cytometry increases the sensitivity and specificity of leptomeningeal disease detection in CNS lymphomas. Both methods should be applied concurrently for complementary diagnostic assessment in patients with CNS lymphoma.

Salvage radiotherapy in patients with recurrent or refractory primary or secondary central nervous system lymphoma after methotrexate-based chemotherapy

BACKGROUND

To assess the efficacy of salvage radiation therapy (RT) in patients with recurrent/refractory primary or secondary central nervous system lymphoma (CNSL) after initial methotrexate (MTX)-based chemotherapy and to identify factors associated with treatment outcome.

PATIENTS AND METHODS

We reviewed 36 patients with primary or secondary CNSL who relapsed after MTX therapy and received salvage RT. Primary end points were radiographic response and overall survival (OS).

RESULTS

After salvage RT, 18 patients (50%) achieved a complete radiographic response and 6 (17%) achieved a partial response, for an overall response rate of 67% [95% confidence interval (CI) 49% to 81%]. The median OS from start of salvage RT was 11.7 months (range: 0.6-94.7). Patients treated with less than five cycles of MTX before failure had a significantly shorter OS than patients who received five or more cycles (9.2 months versus not reached, P = 0.04). Patients with CNSL limited to brain only had a significantly longer OS than patients with disease in the brain and other central nervous system locations (16.5 versus 4.5 months, P=0.01).

CONCLUSION

Salvage RT is effective for patients with recurrent/refractory primary or secondary CNSL after initial MTX therapy. Having received five or more cycles of MTX before failure and CNSL limited to the brain at relapse are associated with longer OS.

Primary central nervous system lymphoma

There is no class I evidence for any therapeutic option in primary central nervous system lymphoma (PCNSL). When possible, patients should be included in clinical trials. The role of surgery is restricted to stereotactic biopsy in order to gain material for histopathologic diagnosis. Radiotherapy alone is associated with a median survival of no more than 1.5 years; cure is exceptional. However, in patients aged younger than 60 years, cure is the therapeutic aim. Polychemotherapy based on high-dose methotrexate with deferred radiation results in long-term survival in most of these patients and possibly cure in a substantial fraction of these patients. With regard to chemotherapy in PCNSL, the following must be considered: 1) the most efficient drug in PCNSL is methotrexate at a dosage of at least 1.5 g/m(2) per single dose; 2) methotrexate alone will lead to complete remission in only some patients, whereas the combination of methotrexate with other drugs is more efficient; and 3) the value of additional intraventricular chemotherapy and the necessity of "consolidation" radiotherapy after response to chemotherapy are not yet defined. For patients aged older than 60 years, no curative regimen with acceptable toxicity has yet been established. The combination of radiotherapy with methotrexate-based chemotherapy leads to severe long-term neurotoxic sequelae, ie, cognitive dysfunction, in most older patients and in some patients aged younger than 60 years.

Detection of free immunoglobulin light chains in cerebrospinal fluids of patients with central nervous system lymphomas

Diagnosis of central nervous system (CNS) lymphoma depends on histopathology of brain biopsies, because no reliable disease marker in the cerebrospinal fluid (CSF) has been identified yet. B-cell lymphomas such as CNS lymphomas are clonally restricted and express either kappa or lambda immunoglobulin light chains. The aim of this study was to find out a potential diagnostic value of free immunoglobulin light chains released into the CSF of CNS lymphoma patients. Kappa (kappa) and lambda (lambda) free immunoglobulin light chains (FLC) were measured in CSF and serum samples collected from 21 patients with primary and secondary CNS lymphomas and 14 control patients with different neurologic disorders. FLC concentrations and ratios were compared between patient groups and were further analyzed in correlation with clinical, cytopathological, and radiological findings. FLC concentrations for all patients were lower in CSF when compared to serum. In patients with CNS lymphoma, the FLC ratios in CSF were higher (range 392-0.3) compared to control patients (range 3.0-0.3). Irrespective of cytopathological proven lymphomatous meningitis, in 11/21 lymphoma CSF samples the FLC ratios were markedly above 3.0 indicating a clonally restricted B-cell population. Increased FLC ratios in CSF were found in those patients showing subependymal lymphoma contact as detected in magnetic resonance imaging. In summary, this is the first report demonstrating that a significant proportion of patients with CNS lymphomas display a markedly increased FLC ratio in the CSF.

Early complete response during chemotherapy predicts favorable outcome in patients with primary CNS lymphoma

In primary central nervous system lymphoma (PCNSL), 2 international prognostic scores have been developed to estimate the outcome according to certain "prognostic groups". However, these scores do not predict the individual course of a single patient under therapy. In this analysis, we addressed the question of whether early tumor remission in patients still under therapy, according to magnetic resonance imaging (MRI) criteria, helps to predict long-term outcome. Eighty-eight patients treated with 6 polychemotherapy cycles within a pilot/phase II trial underwent MRI scanning within 72 hours prior to initiation of therapy, after the second chemotherapy cycle, and after completion of chemotherapy. Response was assessed by contrast-enhanced MRI of the brain according to the Macdonald criteria. Median follow-up was 42 months (range, 0-124 months). Patients achieving a complete radiographic response after 2 courses of chemotherapy (n = 18) had a significantly longer median overall survival (OS) (not reached) and median time-to-treatment failure (TTF) (not reached) than patients with complete response (CR) after termination of treatment but with only a partial response after the second cycle (n = 24) (OS: 55 months; TTF: 32 months) (P < .01). Early complete tumor response assessed by MRI after the second of sixth scheduled chemotherapy cycles was highly predictive for both OS and TTF in patients with PCNSL treated in this series.

Management of immunocompetent patients with primary central nervous system lymphoma

Primary central nervous system (CNS) lymphoma (PCNSL) is a non-Hodgkin lymphoma that arises within and is confined to the CNS. Recent data have suggested an increasing incidence in immunocompetent individuals, with a peak of incidence between 60 and 70 years of age. Patients with PCNSL present mostly with symptoms of increased intracranial pressure. The clinical management of these patients remains controversial, and the optimal treatment for patients with PCNSL has not yet been defined. Surgery, even if macroscopically radical, does not improve survival because of the multifocal and infiltrative nature of PCNSL; furthermore, the deep location of most of these tumors makes patients susceptible to serious and irreversible neurologic sequelae. Corticosteroids have a specific role in the treatment of patients with PCNSL, whose disease is sensitive to them as a chemotherapeutic agent. PCNSL is an extremely radiation-sensitive neoplasm; whole-brain radiation therapy plus corticosteroids was the first modality of treatment for patients with this neoplasm until 10 years ago, with a low cure rate and a high local recurrence rate. PCNSL is also a chemosensitive neoplasm; while the optimal choice, sequence, and combination of appropriate agents for efficacious treatment of patients with PCNSL has yet to be determined. An essential component of therapy must include an adequate drug delivery behind a normal blood-brain barrier. Methotrexate is the agent with the most proven activity in PCNSL. Combined-modality therapy has improved survival, but relapse is still common, and late neurologic toxicity is a significant complication, especially in older patients, who represent the majority of immunocompetent patients with PCNSL.

High-dose methotrexate and rituximab with deferred radiotherapy for newly diagnosed primary B-cell CNS lymphoma

We conducted a prospective Phase II study of high-dose methotrexate (HD-MTX) and rituximab with deferred whole brain radiotherapy in patients with newly diagnosed B-cell primary central nervous system lymphoma with a primary objective of evaluating progression-free survival (PFS). Forty patients (25 men; 15 women), ages 18-93 years (median 61.5), were treated. All patients received biweekly HD-MTX/rituximab (8 g/m(2)/dose; 375 mg/m(2)/dose) for 4-6 cycles (induction) and following best radiographic response, with every 4 weeks HD-MTX (8 g/m(2)/dose) for 4 cycles (maintenance). Neurological and neuroradiographic evaluation were performed every 4 weeks during induction therapy and every 8 weeks during maintenance therapy. All patients were evaluable. A total of 303 cycles of HD-MTX (median 8 cycles; range 4-10) was administered. HD-MTX/rituximab-related toxicity included 16 grade 3 adverse events in 13 patients (32.5%). Following induction, 8 patients (20%) demonstrated progressive disease and discontinued therapy; 32 patients (80%) demonstrated a partial (8/40; 20%) or complete (24/40; 60%) radiographic response. At the conclusion of maintenance therapy (6-10 months of total therapy), 28 patients (70%) demonstrated either a partial (1/28) or complete (27/28) response. Overall, survival of these 28 patients ranged from 11 to 80 months (median 33.5). Survival in the entire cohort ranged from 6 to 80 months with an estimated median of 29 months. Overall, PFS ranged from 2 to 80 months (median 21.0). HD-MTX/rituximab and deferred radiotherapy demonstrated similar or better efficacy similar to other HD-MTX-only regimens and reduced time on therapy on average to 6 months.

Combined Modality Treatment Including Methotrexate-Based Chemotherapy For Primary CENTRAL Nervous System Lymphoma: A Single Institution Experience

Chemotherapy including high-dose methotrexate (HD-MTX), with or without radiotherapy, is standard treatment for primary central nervous system lymphoma (PCNSL). It remains controversial whether addition of other drugs will add to therapeutic efficacy. We report here on 41 patients with PCNSL treated using a combined treatment modality, including HD-MTX (3.5 g/m² for 2 cycles) prior to whole brain radiotherapy (WBRT). In 22 patients, the chemotherapy was intensified by adding high-dose cytosine arabinoside (HD-AraC) (2g/m² for 4 doses for 2 cycles). Complete remission at the end of the combined treatment was obtained in 23 of 34 assessable patients (67%), and the predicted 5-year overall and disease-free survival rates were 24% and 46%, respectively, without differences between treatment groups. The addition of HD-AraC was complicated by severe infections in 17/22 (77%) patients, resulting in 3 toxic deaths. Our study indicates that addition of HD-AraC may not improve clinical outcome in PCNSL, while it increases toxicity. More targeted and less toxic therapies are warranted.

High-dose cytarabine plus high-dose methotrexate versus high-dose methotrexate alone in patients with primary CNS lymphoma: a randomised phase 2 trial

BACKGROUND

Chemotherapy with high-dose methotrexate is the conventional approach to treat primary CNS lymphomas, but superiority of polychemotherapy compared with high-dose methotrexate alone is unproven. We assessed the effect of adding high-dose cytarabine to methotrexate in patients with newly diagnosed primary CNS lymphoma.

METHODS

This open, randomised, phase 2 trial was undertaken in 24 centres in six countries. 79 patients with non-Hodgkin lymphoma exclusively localised into the CNS, cranial nerves, or eyes, aged 18-75 years, and with Eastern Cooperative Oncology Group performance status of 3 or lower and measurable disease were centrally randomly assigned by computer to receive four courses of either methotrexate 3.5 g/m(2) on day 1 (n=40) or methotrexate 3.5 g/m(2) on day 1 plus cytarabine 2 g/m(2) twice a day on days 2-3 (n=39). Both regimens were administered every 3 weeks and were followed by whole-brain irradiation. The primary endpoint was complete remission rate after chemotherapy. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00210314.

FINDINGS

All randomly assigned participants were analysed. After chemotherapy, seven patients given methotrexate and 18 given methotrexate plus cytarabine achieved a complete remission, with a complete remission rate of 18% (95% CI 6-30) and 46% (31-61), respectively, (p=0.006). Nine patients receiving methotrexate and nine receiving methotrexate plus cytarabine achieved a partial response, with an overall response rate of 40% (25-55) and 69% (55-83), respectively, (p=0.009). Grade 3-4 haematological toxicity was more common in the methotrexate plus cytarabine group than in the methotrexate group (36 [92%] vs six [15%]). Four patients died of toxic effects (three vs one).

INTERPRETATION

In patients aged 75 years and younger with primary CNS lymphoma, the addition of high-dose cytarabine to high-dose methotrexate provides improved outcome with acceptable toxicity compared with high-dose methotrexate alone.

FUNDING

Swiss Cancer League.

Diffusion-weighted MR imaging derived apparent diffusion coefficient is predictive of clinical outcome in primary central nervous system lymphoma

BACKGROUND AND PURPOSE

There is evidence that increased tumor cellular density within diagnostic specimens of primary central nervous system lymphoma (PCNSL) may have significant prognostic implications. Because cellular density may influence measurements of apparent diffusion coefficient (ADC) by using diffusion-weighted MR imaging (DWI), we hypothesized that ADC measured from contrast-enhancing regions might correlate with clinical outcome in patients with PCNSL.

MATERIALS AND METHODS

PCNSL tumors from 18 immunocompetent patients, treated uniformly with methotrexate-based chemotherapy, were studied with pretherapeutic DWI. Enhancing lesions were diagnosed by pathologic analysis as high-grade B-cell lymphomas. Regions of interest were placed around all enhancing lesions allowing calculation of mean, 25th percentile (ADC(25%)), and minimum ADC values. Histopathologic tumor cellularity was quantitatively measured in all patients. High and low ADC groups were stratified by the median ADC value of the cohort. The Welch t test assessed differences between groups. The Pearson correlation examined relationships between ADC measurements and tumor cellular density. Single and multivariable survival analysis was performed.

RESULTS

We detected significant intra- and intertumor heterogeneity in ADC measurements. An inverse correlation between cellular density and ADC measurements was observed (P < .05). ADC(25%) measurements less than the median value of 692 (low ADC group) were associated with significantly shorter progression-free and overall survival. Patients with improved clinical outcome were noted to exhibit a significant decrease in ADC measurements following high-dose methotrexate chemotherapy.

CONCLUSIONS

Our study provides evidence that ADC measurements within contrast-enhancing regions of PCNSL tumors may provide noninvasive insight into clinical outcome.

High-dose methotrexate for elderly patients with primary CNS lymphoma

The introduction of methotrexate (MTX)-based chemotherapy has improved median survival for patients with primary CNS lymphoma (PCNSL). Older age is a negative prognostic marker in patients with PCNSL and may increase the likelihood of MTX toxicity. We studied the response and adverse effects of intravenous high-dose MTX in patients who were 70 or more years of age at the time of diagnosis. We identified 31 patients at our institution diagnosed with PCNSL at age > or =70 years (median, 74 years) who were treated with high-dose MTX (3.5-8 g/m(2)) as initial therapy from 1992 through 2006. The best response to MTX was determined by contrast-enhanced MRI. Toxicity was analyzed by chart review. These 31 patients received a total of 303 cycles of MTX (median, eight cycles per patient). Overall, 87.9% of the cycles required dose reduction because of impaired creatinine clearance. In 30 evaluable patients, the overall radiographic response rate was 96.7%, with 18 complete responses (60%) and 11 partial responses (36.7%). Progression-free survival and overall survival were 7.1 months and 37 months, respectively. Grade I-IV toxicities were observed in 27 of 31 patients and included gastrointestinal disturbances in 58% (3.2% grade III), hematological complications in 80.6% (6.5% grade III), and renal toxicity in 29% (0% grade III/IV). High-dose MTX is associated with a high proportion of radiographic responses and a low proportion of grade III/IV toxicity in patients 70 or more years of age. High-dose MTX should be considered as a feasible treatment option in elderly patients with PCNSL.

Efficacy and MRI of rituximab and methotrexate treatment in a nude rat model of CNS lymphoma

To determine the efficacy of methotrexate and/or rituximab in a CNS lymphoma model and to evaluate MRI modalities for monitoring efficacy, we inoculated female athymic nude rats (rnu/rnu) intracerebrally with human MC116 B-lymphoma cells. Between days 16 and 26, rats were randomized to receive intravenous (IV) treatment with (1) saline (controls, n = 15), (2) methotrexate 1,000 mg/m(2) (n = 6), (3) rituximab 375 mg/m(2) (n = 6), or (4) rituximab plus methotrexate (n = 6). T2/fluid-attenuated inversion recovery (FLAIR) and gadolinium contrast-enhanced T1 MRI sequences were performed prior to and 1 week after treatment. IV rituximab gave an objective tumor response in four of six animals (>50% reduction in tumor volume comparing pre- and posttreatment T2/FLAIR MRI) and resulted in stable disease (50%-125% of baseline) in another animal. The percent change in tumor volume on T2/FLAIR images was significantly different in the control versus rituximab group (p = 0.0051). IV methotrexate slowed tumor growth, compared to controls, but only one of six animals had an objective response. In untreated controls, tumor histological volumes correlated well with T2/FLAIR or contrast-enhanced T1 images (r = 0.877). In the treatment groups, T2/FLAIR correlation was good, but the gadolinium-enhanced T1 MRI was not significantly correlated with histology (r = 0.19). The MC116 CNS lymphoma model seems valuable for preclinical testing of efficacy and toxicity of treatment regimens. IV rituximab was highly effective, but methotrexate was only minimally effective. T2/FLAIR was superior to contrast-enhanced T1 for monitoring efficacy.

Primary lymphoma of the central nervous system: epidemiology, pathology and current approaches to diagnosis, prognosis and treatment

An overview of the current approaches to the management of patients with primary central nervous system lymphoma (PCNSL) is provided. Although accumulating evidence demonstrates that PCNSL is a curable type of brain tumor, in many cases establishing the diagnosis and overcoming chemotherapeutic resistance remain significant obstacles. The issue of treatment-related neurotoxicity is also a central consideration in treatment planning. The introduction of highly active antiretroviral therapy has had a major impact on this disease in that the incidence of AIDS-related central nervous system lymphoma, once highly prevalent in the 1980s and 1990s, has now virtually disappeared. However, the problem of diagnostic delays secondary to steroid effects, radiation-induced neurotoxicity and methotrexate resistance represent unique and important problems in this disease. The use of anti-CD20 antibody in this disease represents the first application of biologically based targeted therapies for PCNSL; however, the overall impact of this modality in brain lymphoma awaits further evaluation in ongoing studies The application of proteomic as well as gene expression technologies is yielding insights into PCNSL pathogenesis, in particular specific oncogenic pathways, which may be exploited to develop new therapies.

Differential diagnosis of white matter diseases in the tropics: An overview

In hospitals in the tropics, the availability of magnetic resonance imaging (MRI) facilities in urban areas and especially in teaching institutions have resulted in white matter diseases being frequently reported in a variety of clinical settings. Unlike the west where multiple sclerosis (MS) is the commonest white matter disease encountered, in the tropics, there are myriad causes for the same. Infectious and post infectious disorders probably account for the vast majority of these diseases. Human immunodeficiency virus (HIV) infection tops the list of infective conditions. Central nervous system (CNS) tuberculosis occasionally presents with patchy parenchymal lesions unaccompanied by meningeal involvement. Human T cell leukemia virus (HTLV) infection and cystic inflammatory lesions such as neurocysticercosis are important causes to be considered in the differential diagnosis. Diagnosing post infectious demyelinating disorders is equally challenging since more than a third of cases seen in the tropics do not present with history of past infection or vaccinations. Metabolic and deficiency disorders such as Wernicke's encephalopathy, osmotic demyelinating syndrome associated with extra pontine lesions and Vitamin B12 deficiency states can occassionaly cause confusion in diagnosis. This review considers a few important disorders which manifest with white matter changes on MRI and create diagnostic difficulties in a population in the tropics.

Ifosfamide or trofosfamide in patients with intraocular lymphoma

We evaluated response, progression-free survival (PFS), overall survival (OS), relapse patterns and long-term toxicity of intraocular lymphoma (IOL) patients treated with ifosfamide (IFO) or trofosfamide (TRO). In a prospective single center study, IFO or TRO were given to 10 patients with IOL. The median patient age was 73 (range 46-83) years. Six patients were pretreated with up to four treatment regimens for ocular or cerebral lymphoma, and four were therapy-naive. All patients responded, including nine complete remissions and one partial remission, with a median PFS of 18 (7-36) months. Seven patients relapsed: five in the eye and two in the brain. Median OS was 32 (7-37+) months. No long-term toxicity was observed in patients treated with IFO or TRO alone. IFO or TRO were active and well tolerated in this study. Thus, they may represent suitable combination partners for other cytostatics used for PCNSL and IOL treatment.

First report on a prospective trial with yttrium-90-labeled ibritumomab tiuxetan (Zevalin) in primary CNS lymphoma

Most patients with primary CNS lymphoma (PCNSL) relapse after primary therapy. Standard salvage treatment has not yet been established in PCNSL. Anti-CD20 immunotherapy has expanded treatment options in systemic B-cell lymphoma; however, its use is limited by reconstitution of the blood-brain barrier after tumor shrinkage. The aim of this phase II trial was to evaluate the therapeutic efficacy, toxicity, and biodistribution of yttrium-90 ((90)Y) ibritumomab tiuxetan in PCNSL. Ten patients with relapsed PCNSL were included in a phase II trial and treated with the (90)Y-labeled anti-CD20 antibody ibritumomab tiuxetan. Nine patients actually received the planned radioimmunotherapy. In six patients, biodistribution of the antibody was measured by indium-111 ((111)In) ibritumomab tiuxetan whole-body scans and single-photon-emission CT (SPECT) of the brain. All patients were evaluated for toxicity and response at least 4 weeks after therapy. Four patients responded: one patient had a complete response lasting 30+ months, and three patients had short-lived responses of </=4 weeks. Five patients progressed, and one patient did not receive treatment due to an infection prior to (90)Y-antibody administration. Target accumulation of the antibody was demonstrated in four of the six patients examined by SPECT imaging with (111)In ibritumomab tiuxetan. All patients experienced grade 3/4 hematotoxicity but no acute neurotoxicity. Penetration of a therapeutic antibody into PCNSL and significant clinical activity was shown. Because of limited response duration and considerable hematotoxicity, future investigations should focus on a multimodal approach with additional chemotherapy and preferably autologous stem cell support.

Primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is an uncommon extranodal non-Hodgkin lymphoma. Its incidence has increased during the last 3 decades and has been reported in both immunocompromised and immunocompetent patients. Immunocompromised patients are affected at a younger age compared with immunocompetent patients. It presents with raised intracranial pressure and focal neurologic and neuropsychiatric symptoms. The lesions are typically solitary. The majority of the lesions are located in the periventricular area, whereas in a few cases they are located in the supratentorial area. Diffuse large B-cell lymphomas constitute most PCNSLs, whereas T-cell, low-grade, anaplastic, and Hodgkin lymphomas are rarely encountered. The morphology of PCNSL shows a characteristic angiocentric pattern and is positive for B-cell markers by immunohistochemistry. The differential diagnosis of PCNSL includes central nervous system gliomas, metastatic tumors, demyelinating disorders, subacute infarcts, and space-occupying lesions due to an infectious etiology. The understanding of the molecular mechanisms involved in the pathogenesis of PCNSL and the identification of molecular biomarkers have lagged behind that of systemic nodal lymphomas. Primary central nervous system lymphomas are treated with combined radiotherapies and chemotherapies. The prognosis for PCNSL is worse than for other extranodal lymphomas.

High-dose methotrexate combined with procarbazine and CCNU for primary CNS lymphoma in the elderly: results of a prospective pilot and phase II study

BACKGROUND

To improve survival of elderly patients with primary central nervous system lymphoma (PCNSL), we conducted a phase II study with high-dose methotrexate (MTX) combined with procarbazine and CCNU. To reduce neurotoxicity, whole-brain irradiation was reserved for patients not responding to chemotherapy.

PATIENTS AND METHODS

High-dose MTX was applied on days 1, 15, and 30, procarbazine on days 1-10, and CCNU on day 1. Study treatment comprised up to three 45-day cycles. There was no lower limit of Karnofsky performance status (KPS).

RESULTS

Thirty patients with PCNSL (n = 29) or primary ocular lymphoma (n = 1) were included (median age 70 years, range 57-79 years). The median initial KPS was 60% (range 30%-90%). Best documented response in 27 assessable patients were 12 of 27 (44.4%) complete remissions, 7 of 27 (25.9%) partial remissions, and 8 of 27 (29.6%) disease progressions. Two patients died of probable treatment-related causes. With a median follow-up of 78 months (range 34-105), the 5-year overall survival is 33%. Eight of 30 patients (26.7%) are currently alive and well, six without signs of leukoencephalopathy.

CONCLUSION

The combination of high-dose MTX with procarbazine and CCNU is feasible and effective and results in a low rate of leukoencephalopathy. Comorbidity and toxicity remain of concern when treating PCNSL in elderly patients.

Systemic high-dose methotrexate plus ifosfamide is highly effective for central nervous system (CNS) involvement of lymphoma

Patients with malignant central nervous system (CNS) involvement of lymphoma have a poor prognosis with intrathecal chemotherapy and radiation. In this paper, we report the results we obtained in such patients by intravenous chemotherapy with high-dose methotrexate and ifosfamide (HDMTX/IFO). The study involved a review of all patients who received HDMTX/IFO for CNS involvement of malignant lymphoma at our hospital. Therapy consisted of 4 g/m(2) of MTX (4 h infusion on day 1) and 1.5-2 g/m(2)/day of IFO (3 h infusion on days 3-5). The study included 20 patients with a median age of 65 years (range, 30-83) and CNS relapse of a malignant lymphoma. Seventeen patients had been pretreated with up to two chemotherapy regimens. The objective response rate was 90% with 12 complete or unconfirmed complete (CR and CRu) and six partial remissions. All patients had at least stabilization of their neurological symptoms. Myelosuppression was the most common toxicity. The median follow-up time was 14.9 months. The median time to neurological progression was 8.9 months. Twelve patients received subsequent therapy, including high-dose chemotherapy with autologous stem cell transplantation in five cases. The median overall survival was not reached. Systemic chemotherapy with HDMTX/IFO is a feasible and promising treatment modality for CNS relapse of a malignant lymphoma.

Extranodal marginal zone lymphoma of the dura mater with IgH/MALT1 translocation and review of literature

Primary central nervous system lymphoma (PCNSL) is an extranodal non-Hodgkin lymphoma involving brain, intraocular structures and spinal cord, without evidence of systemic disease. The majority of PCNSLs are diffuse large B-cell type. We encountered a rare case of primary dural marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) with extension into the brain in a 59-year-old man. A magnetic resonance imaging scan showed a 22-mm tumor located in the left posterior temporal lobe extending from the dura. Histopathology revealed a lymphoplasmacytic infiltration of the dura and the brain parenchyma in a perivascular pattern. Immunohistochemical and in situ hybridization studies showed a B-cell phenotype with kappa light chain restriction. Fluorescent in situ hybridization study showed a t(14;18)(q32;q21) with immunoglobulin heavy-chain/MALT1 fusion. The molecular study for immunoglobulin heavy-chain gene rearrangement by polymerase chain reaction showed a clonal gene rearrangement.

Primary central nervous system lymphoma: monocenter, long-term, intent-to-treat analysis

BACKGROUND

This retrospective, single-center study assessed the feasibility, outcome, and late side effects of the treatment of immunocompetent patients with primary central nervous system lymphoma (PCNSL) at the authors' institution.

METHODS

All 72 consecutive patients diagnosed with PCNSL between January 1994 and February 2005 were scheduled to receive high-dose methotrexate (HDMTX)-based chemotherapy.

RESULTS

The median age of the patients was 62 years and the median Karnofsky performance score (KPS) was 70. Twelve patients did not receive HDMTX-based chemotherapy because of poor physical condition or renal insufficiency. Of the 60 patients treated with HDMTX-based chemotherapy, the treatment of 9 was followed with whole-brain irradiation. Of 54 patients who were evaluable for response, 35 (65%) responded (52% with a complete response and 13% with a partial response), and 19 patients (35%) did not. At a median follow-up of 58.7 months, the median progression-free survival was 9 months and the median overall survival (OAS) was 41.4 months. According to the Memorial Sloan-Kettering Cancer Center (MSKCC) prognosis score, patients could be divided into 3 groups with significantly different OAS: 52.9 months for patients aged <50 years, 42.4 months for patients aged >or= 50 years and with a KPS >70, and 5.2 months for patients aged >or= 50 years and with a KPS <70 (P= .009, log-rank test).

CONCLUSIONS

Promising long-term results could be achieved with HDMTX-based chemotherapy in patients with PCNSL in this monocenter study. The MSKCC score proved useful for predicting survival.

Intensive chemotherapy followed by hematopoietic stem-cell rescue for refractory and recurrent primary CNS and intraocular lymphoma: Société Française de Greffe de Moëlle Osseuse-Thérapie Cellulaire

PURPOSE

The prognosis of relapsing primary CNS lymphoma (PCNSL) is poor. We report the results of a prospective multicenter trial of intensive chemotherapy followed by autologous hematopoietic stem-cell rescue (IC + HCR) in immunocompetent adult patients with PCNSL or intraocular lymphoma (IOL) after failure of high-dose methotrexate-based treatment.

PATIENTS AND METHODS

Salvage treatment consisted of two cycles of high-dose cytarabine and etoposide (CYVE). Intensive chemotherapy combined thiotepa, busulfan, and cyclophosphamide. Forty-three patients (median age, 52 years; range, 23 to 65 years) were included, with relapse (n = 22), refractory disease (n = 17), or a partial response to first-line treatment (n = 4). The response to CYVE was not assessable in three cases because of treatment-related death. Twenty patients (47%) were chemosensitive to CYVE: 15 of them proceeded to IC + HCR. IC + HCR was also administered to 12 patients who did not respond to CYVE. All but one of the 27 patients who underwent IC + HCR entered complete remission.

RESULTS

With a median follow-up of 36 months, the median overall survival was 18.3 months in the overall population, and 58.6 months among patients who completed IC + HCR. The respective median progression-free survival (PFS) times after IC + HCR were 11.6 and 41.1 months. The 2-year overall survival probability was 45% in the whole population and 69% among the 27 patients who received IC + HCR. The 2-year PFS probability was 43% among all the patients and 58% in the IC + HCR subpopulation.

CONCLUSION

IC + HCR is an effective treatment for refractory and recurrent PCNSL.

The utility of body FDG PET in staging primary central nervous system lymphoma

(18)F-Fluorodeoxyglucose (FDG) PET has become an important tool in the management of non-Hodgkin's lymphoma (NHL), but its role in the evaluation of primary CNS lymphoma (PCNSL) has not been established. We investigated the ability of body FDG PET to detect systemic disease in the staging and restaging of PCNSL. The records of 166 PCNSL patients seen at Memorial Sloan-Kettering Cancer Center were examined. Forty-nine patients who underwent body FDG PET for staging of PCNSL were identified. Clinical data were reviewed to determine FDG PET results and their influence on therapy. Body FDG PET disclosed a systemic site of malignancy in 15% of patients. NHL was found in 11% of all patients, 7% of patients at diagnosis, and 27% of patients at CNS relapse. Four percent had a second systemic neoplasm. Workup with conventional staging did not reveal systemic disease, and in 8% of patients, body FDG PET was the only abnormal diagnostic exam suggestive of lymphoma. FDG PET findings altered patient treatment and resulted in additional chemotherapy, surgery, or radiotherapy. Our findings suggest that FDG PET may be more sensitive than conventional body staging and may disclose higher rates of concomitant systemic disease at PCNSL diagnosis. Body FDG PET may be an important noninvasive adjunct to conventional PCNSL staging, and its utility should be evaluated prospectively.

Study of radiolabeled indium-111 and yttrium-90 ibritumomab tiuxetan in primary central nervous system lymphoma

BACKGROUND

Therapeutic options for refractory or recurrent primary central nervous system lymphoma (PCNSL) are limited. The blood-brain barrier makes many agents used in systemic lymphomas ineffective in CNS lymphomas. The objective of this study was to determine whether intravenous radioimmunotherapy using anti-CD20 antibody can be delivered to PCNSL.

METHODS

This was a single-institution prospective study. Indium-111 ibritumomab tiuxetan was used for imaging and dosimetry. Yttrium-90 ibritumomab tiuxetan at doses of 0.3 to 0.4 mCi/kg were subsequently given for the treatment of recurrent or refractory PCNSL. 111In data were used to estimate radiation doses to lesions delivered by 90Y ibritumomab tiuxetan therapy.

RESULTS

Six patients (4 men, 2 women) with a median age of 60 years and median Karnofsky performance status of 70 received both indium-111 and yttrium-90 ibritumomab tiuxetan. The median absorbed dose delivered to the CNS lymphoma was 701 cGy compared with 70 cGy to normal brain. The median progression-free and overall survival times were 6.8 weeks and 14.3 weeks, respectively.

CONCLUSIONS

The results from this study suggest that it may be feasible to deliver radiolabeled monoclonal anti-CD20 antibodies as a component of therapy for PCNSL.

Protein biomarker identification in the CSF of patients with CNS lymphoma

PURPOSE

Elucidation of the CSF proteome may yield insights into the pathogenesis of CNS disease. We tested the hypothesis that individual CSF proteins distinguish CNS lymphoma from benign focal brain lesions.

METHODS

We used a liquid chromatography/mass spectrometry-based method to differentially quantify and identify several hundred CSF proteins in CNS lymphoma and control patients. We used enzyme-linked immunosorbent assay (ELISA) to confirm one of these markers in an additional validation set of 101 cases.

RESULTS

Approximately 80 CSF proteins were identified and found to be present at significantly different concentrations, both higher and lower, in training and test studies, which were highly concordant. To further validate these observations, we defined in detail the expression of one of these candidate biomarkers, antithrombin III (ATIII). ATIII RNA transcripts were identified within CNS lymphomas, and ATIII protein was localized selectively to tumor neovasculature. Determination of ATIII concentration by ELISA was significantly more accurate (> 75% sensitivity; > 98% specificity) than cytology in the identification of cancer. Measurement of CSF ATIII levels was found to potentially enhance the ability to diagnose and predict outcome.

CONCLUSION

Our findings demonstrate for the first time that proteomic analysis of CSF yields individual biomarkers with greater sensitivity in the identification of cancer than does CSF cytology. We propose that the discovery of CSF protein biomarkers will facilitate early and noninvasive diagnosis in patients with lesions not amenable to brain biopsy, as well as provide improved surrogates of prognosis and treatment response in CNS lymphoma and brain metastasis.

Response assessment in lymphoma

The lymphomas are a heterogeneous group of malignant diseases. They are divided into two broad groups: Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL). Patients suffering from HD and NHL can be cured by appropriate chemotherapy and/or radiotherapy. Accurate staging and response assessment is essential to guide management decisions. The International Workshop Group (IWG) criteria, published in 1999, have become the widely accepted standard for response assessment in NHL. Although the IWG criteria have proved extremely useful in the standardization of treatment response, they do have a number of limitations. As a consequence of this, together with advances in functional imaging, revised criteria have been published recently. The aim of this review is to describe the evidence supporting the available imaging techniques, the limitations of each technique, and how these should be applied in clinical practice. We briefly review the corresponding response criteria for central nervous system (CNS) lymphomas, and take a look at novel imaging techniques that may play a role in the future.

Combined immunochemotherapy with reduced whole-brain radiotherapy for newly diagnosed primary CNS lymphoma

PURPOSE

Our goals were to evaluate the safety of adding rituximab to methotrexate (MTX)-based chemotherapy for primary CNS lymphoma, determine whether additional cycles of induction chemotherapy improve the complete response (CR) rate, and examine effectiveness and toxicity of reduced-dose whole-brain radiotherapy (WBRT) after CR.

PATIENTS AND METHODS

Thirty patients (17 women; median age, 57 years; median Karnofsky performance score, 70) were treated with five to seven cycles of induction chemotherapy (rituximab, MTX, procarbazine, and vincristine [R-MPV]) as follows: day 1, rituximab 500 mg/m2; day 2, MTX 3.5 gm/m2 and vincristine 1.4 mg/m2. Procarbazine 100 mg/m2/d was administered for 7 days with odd-numbered cycles. Patients achieving CR received dose-reduced WBRT (23.4 Gy), and all others received standard WBRT (45 Gy). Two cycles of high-dose cytarabine were administered after WBRT. CSF levels of rituximab were assessed in selected patients, and prospective neurocognitive evaluations were performed.

RESULTS

With a median follow-up of 37 months, 2-year overall and progression-free survival was 67% and 57%, respectively. Forty-four percent of patients achieved a CR after five or fewer cycles, and 78% after seven cycles. The overall response rate was 93%. Nineteen of 21 CR patients received the planned 23.4 Gy WBRT. The most commonly observed grade 3 to 4 toxicities included neutropenia (43%), thrombocytopenia (36%), and leukopenia (23%). No treatment-related neurotoxicity has been observed.

CONCLUSION

The addition of rituximab to MPV increased the risk of significant neutropenia requiring routine growth factor support. Additional cycles of R-MPV nearly doubled the CR rate. Reduced-dose WBRT was not associated with neurocognitive decline, and disease control to date is excellent.