Urokinase-type plasminogen-activator (upa), a protease with cytokine-like activity in human hl-60 leukemic-cell line

HL-60, a cell line originating from a human myeloid leukemia, expresses urokinase-type plasminogen activator (uPA) on the mRNA level and secretes the protein into the culture supernatant. Additionally, uPA receptors (uPA-R) could be detected in HL-60 on both the mRNA and the protein level, whereas the lymphoblastic cell line Raji studied in parallel was uPA-R negative. The cell lines were further studied in their clonal growth in methylcellulose under the influence of rhuPA (rhpro-uPA). The growth of Raji cells was not influenced by rhuPA. Colony and cluster formation of HL-60 was not reproducibly affected by rhuPA in concentrations between 1-100 ng/ml. In some experiments however, there were higher numbers of colonies in the HL-60 cultures incubated with rhuPA which was due to a cluster-to-colony shift. Furthermore, the HL-60 colonies in the rhuPA incubated plates always showed morphological alterations including an adherent basis indicating functional differentiation. This assumption was further supported by the observation that the secondary plating efficiency (PE2) of HL-60 cells taken from single colonies of uPA-incubated plates decreased significantly when compared with PE2 of cells from colonies grown without the presence of uPA. In conclusion, the intact uPA molecule functions like an autocrine cytokine for a human leukemic cell line, which in addition to its effects in tumor invasion makes it an interesting target molecule for further studies on tumor suppression.

Macrophage inflammatory protein (mip)-1-alpha stem-cell inhibitor (sci) does not affect clonal growth of human solid tumor-cell lines in-vitro

MIP-1alpha is a member of a family of proinflammatory cytokines produced by activated macrophages which has been shown to be a negative regulator of early hematopoietic stem cell progenitors. We report on results testing recombinant human (rh) MIP-1alpha on the clonal growth of different human nonhematopoietic tumor cell lines in vitro. Cell lines tested included the following histologies: 7 glioblastomas, 1 neuroblastoma, 2 head and neck carcinomas, 4 lung carcinomas, 3 colorectal carcinomas, 1 gastric carcinoma, 1 pancreatic carcinoma, 1 breast carcinoma, 1 prostate carcinoma, 1 choriocarcinoma, 1 ovary carcinoma, 1 osteosarcoma, and 3 melanomas. MIP-1alpha (0, 2, 20, 200 ng/ml) was tested in human tumor cloning assays (HTCA) in agar-containing capillaries (HTCAcap) and in mixtures of methylcellulose and agar (HTCAmix), representing assay systems with different plating efficiencies (PE). Tumor cells were continuously exposed to the cytokine for the complete assay period. Clonal growth of none of the cell lines was significantly and reproducibly stimulated or inhibited by MIP-1alpha.

Mutation and expression of the p53 tumor suppressor gene in tumor samples and cancer cell-lines - comparison of nonisotopic direct DNA-sequencing, immunoblotting and immunohistochemistry

Mutations in the nuclear phosphoprotein p53 are the most frequent genetic alterations in human solid tumors detected so far. These mutations are clustered in highly conserved domains spanning from exon 4 to 9 of the gene. A very precise method of detecting p53 mutations is to sequence these domains. However, 2 to 3 overlapping PCR-amplifications were needed to span the whole mutation-prone region. We used a very rapid non radioactive solid-phase DNA sequencing method starting from mRNA to sequence the p53 domains in both directions with T7 DNA-polymerase allowing detection of the heterozygous state, where one allele shows the wild-type sequence, the other a mutated one. First we sequenced four colon carcinoma cell lines with known p53 mutations and one T-cell-leukemia cell line with a heterozygous situation to validate our method. Using this method we sequenced the p53 gene (exons four to nine) from 16 primary colon carcinomas. Seven of these 16 (44%) carcinomas showed mutations in the p53 gene resulting in amino acid exchanges. One showed a silent mutation, another one showed two point mutations in the highly conserved domain of the p53 gene. These colorectal carcinomas have been examined for overexpression of the p53 protein using a panel of monoclonal antibodies directed against p53 (PAb1801, PAb240, PAb421, PAb1620) by immunohistochemical analysis and immunoblotting. Furthermore, four colorectal cancer cell lines were examined by indirect immunofluorescence technique with the same mAb PAb1801 as used in histological staining. Analysis of 6 out of 15 (40%) tumor specimens revealed markedly positive p53 nuclear staining patterns using monoclonal antibody PAb1801. These data suggest that there is quite a good correlation between point mutation of the p53 gene and nuclear staining with monoclonal antibody PAb1801 detecting overexpressed p53 protein. Moreover, there is no convincing evidence that wild-type protein can be detected using the monoclonal antibodies PAb 1801 and PAb 1620.

Prognostic impact of meningeal dissemination in primary CNS lymphoma (PCNSL): experience from the G-PCNSL-SG1 trial

BACKGROUND

We evaluated the frequency and prognostic impact of meningeal dissemination (MD) in immunocompetent adult patients with primary central nervous system lymphoma treated in a randomized phase III trial.

PATIENTS AND METHODS

MD was evaluated at study entry and defined by lymphoma proof in the meningeal compartment detected by at least one of the following methods: cerebrospinal fluid (CSF) cytomorphology, detection of clonal B cells by IgH PCR in CSF or contrast enhancement of the leptomeninges on magnetic resonance imaging (MRI).

RESULTS

Data on MD were available in 415 patients, of those, MD was detected in 65 (15.7%): in 44/361 (12.2%) by CSF cytomorphology, in 16/152 (10.5%) by PCR and in 17/415 (4.1%) by MRI. Major patients' characteristics and therapy did not significantly differ between patients with MD (MD+) versus those without MD (MD-). There was a significant correlation of MD with CSF pleocytosis (>5/μl; P < 0.0001), but no correlation with CSF protein elevation (>45 mg/dl). Median progression-free survival was 6.7 months [95% confidence interval (CI) 0-14.5] in MD+ and 8.3 months (5.7-10.8) in MD- patients (P = 0.95); median overall survival was 21.5 months (95% CI 16.8-26.1) and 24.9 months (17.5-32.3), respectively (P = 0.98).

CONCLUSION

MD was detected infrequently and had no impact on outcome in this trial.

High-power solid-state cw dye laser

In the present paper we describe a high-power tunable solid-state dye laser setup that offers peak output power up to 800 mW around 575 nm with excellent long-time power stability and low noise level. The spectral width of the laser emission is less than 3 GHz and can be tuned over more than 30 nm. A nearly circular mode profile is achieved with an M(2) better than 1.4. The device can be integrated in a compact housing (dimensions are 60 × 40 × 20 cm(3)). The limitation of long-time power stability is mainly given by photo decomposition of organic dye molecules. These processes are analyzed in detail via spatially resolved micro-imaging and spectroscopic studies.

Antileukemic activity of the HSP70 inhibitor pifithrin-μ in acute leukemia

Heat shock protein (HSP) 70 is aberrantly expressed in different malignancies and has emerged as a promising new target for anticancer therapy. Here, we analyzed the in vitro antileukemic effects of pifithrin-μ (PFT-μ), an inhibitor of inducible HSP70, in acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) cell lines, as well as in primary AML blasts. PFT-μ significantly inhibited cell viability at low micromolar concentrations in all cell lines tested, with IC50 values ranging from 2.5 to 12.7 μ, and was highly active in primary AML blasts with a median IC50 of 8.9 μ (range 5.7–37.2). Importantly, higher IC50 values were seen in normal hematopoietic cells. In AML and ALL, PFT-μ induced apoptosis and cell cycle arrest in a dose-dependent fashion. PFT-μ also led to an increase of the active form of caspase-3 and reduced the intracellular concentrations of AKT and ERK1/2 in NALM-6 cells. Moreover, PFT-μ enhanced cytotoxicity of cytarabine, 17-(allylamino)-17-desmethoxygeldanamycin, suberoylanilide hydroxamic acid, and sorafenib in NALM-6, TOM-1 and KG-1a cells. This is the first study demonstrating significant antileukemic effects of the HSP70 inhibitor PFT-μ, alone and in combination with different antineoplastic drugs in both AML and ALL. Our results suggest a potential therapeutic role for PFT-μ in acute leukemias.

Prognostic relevance of circulating tumor cells in metastatic uveal melanoma

OBJECTIVE

Uveal melanoma primarily metastasizes hematogenously with metastases often confined to the liver. The aim of this study was to investigate the presence of circulating tumor cells (CTC) in patients with metastatic disease as a marker for systemic disease and to determine their prognostic relevance.

METHODS

Blood samples from 68 patients were collected at the time of initial treatment of metastases. mRNA expression of tyrosinase and MelanA/MART1 as a surrogate marker for the presence of CTC was analyzed by real-time RT-PCR and compared with patient characteristics.

RESULTS

CTC were detected in 63% of all patients and in 67% of the 48 patients with only liver metastases. Univariate and multivariate analyses revealed PCR results and serum lactate dehydrogenase as independent prognostic factors for progression-free (hazard ratios 2.2/3.5) and overall survival (hazard ratios 4.0/6.5). Combination of PCR and lactate dehydrogenase divided the patient cohort into 3 groups with distinct prognosis.

CONCLUSION

CTC as evidence for systemic disease can be found in the majority of patients with metastatic uveal melanoma, including patients with visible disease confined to the liver. Detection of CTC-specific mRNA transcripts for tyrosinase and MelanA/MART1 by PCR is a poor prognostic factor for progression-free and overall survival. Characterization of CTC could improve the understanding of their biology.

Genome-wide screen reveals WNT11, a non-canonical WNT gene, as a direct target of ETS transcription factor ERG

E26 transforming sequence-related gene (ERG) is a transcription factor involved in normal hematopoiesis and is dysregulated in leukemia. ERG mRNA overexpression was associated with poor prognosis in a subset of patients with T-cell acute lymphoblastic leukemia (T-ALL) and acute myeloid leukemia (AML). Herein, a genome-wide screen of ERG target genes was conducted by chromatin immunoprecipitation-on-chip (ChIP-chip) in Jurkat cells. In this screen, 342 significant annotated genes were derived from this global approach. Notably, ERG-enriched targets included WNT signaling genes: WNT11, WNT2, WNT9A, CCND1 and FZD7. Furthermore, chromatin immunoprecipitation (ChIP) of normal and primary leukemia bone marrow material also confirmed WNT11 as a target of ERG in six of seven patient samples. A larger sampling of patient diagnostic material revealed that ERG and WNT11 mRNA were co-expressed in 80% of AML (n=30) and 40% in T-ALL (n=30) bone marrow samples. Small interfering RNA (siRNA)-mediated knockdown of ERG confirmed downregulation of WNT11 transcripts. Conversely, in a tet-on ERG-inducible assay, WNT11 transcripts were co-stimulated. A WNT pathway agonist, 6-bromoindirubin-3-oxime (BIO), was used to determine the effect of cell growth on the ERG-inducible cells. The addition of BIO resulted in an ERG-dependent proliferative growth advantage over ERG-uninduced cells. Finally, ERG induction prompted morphological transformation whereby round unpolarized K562 cells developed elongated protrusions and became polarized. This morphological transformation could effectively be inhibited with BIO and with siRNA knockdown of WNT11. In conclusion, ERG transcriptional networks in leukemia converge on WNT signaling targets. Specifically, WNT11 emerged as a direct target of ERG. Potent ERG induction promoted morphological transformation through WNT11 signals. The findings in this study unravel new ERG-directed molecular signals that may contribute to the resistance of current therapies in acute leukemia patients with poor prognosis characterized by high ERG mRNA expression.

[Relapsed pulmonary lymphomatoid granulomatosis grade III: curative treatment with radioimmune therapy and autologous stem cell transplantation]

HISTORY AND ADMISSION FINDINGS

A 36-year-old woman presented with dyspnea, dry cough and severe chest pain. She had been treated for persistent shoulder pain for several months. Clinical findings were non-conclusive. Lactate dehydrogenase was slightly elevated, C-reactive protein was increased.

INVESTIGATIONS

A chest X-ray and subsequent computed tomography (CT) scans showed a lesion measuring 10×8 cm in the right upper pulmonary lobe. A CT-guided biopsy was obtained and the histological examination revealed a dense lymphocytic infiltrate with abundant blasts in addition to areas of necrosis and fibrosis. These findings were consistent with lymphomatoid granulomatosis grade III.

TREATMENT AND COURSE

After 6 cycles of rituximab, cyclophosphamide, doxorubicin, vincristin and prednisolone (R-CHOP), an early relapse developed which was treated with rituximab, ifosphamid, methotrexate and etoposide. Good partial remission was achieved after consolidating high-dose chemotherapy followed by autologous stem cell transplantation (ASCT). After two years of rituximab maintenance treatment positron emission tomography (PET-CT) revealed an increase of metabolic activity. A second high-dose therapy was then combined with Y-90 ibritumomab tiuxetan, which was well tolerated. During remission the previously present lymphoma lesion of the lung was resected. Histology did not reveal any residual active lymphomatoid granulomatosis. Complete remission has so far been maintained for one year after ASCT.

CONCLUSIONS

Combination of Y-90 ibritumomab tiuxetan and high-dose chemotherapy followed by ASCT may offer an efficacious and well-tolerated targeted treatment approach for patients with relapsed lymphomatoid granulomatosis.

BAALC-associated gene expression profiles define IGFBP7 as a novel molecular marker in acute leukemia

Over expression of BAALC (brain and acute leukemia, cytoplasmic) predicts an inferior outcome in acute myeloid leukemia (AML) and acute lymphoblastic leukemia patients. To identify BAALC-associated genes that give insights into its functional role in chemotherapy resistance, gene expression signatures differentiating high from low BAALC expressers were generated from normal CD34(+) progenitors, T-acute lymphoblastic leukemia (T-ALL) and AML samples. The insulin-like growth factor binding protein 7 (IGFBP7) was one of the four genes (CD34, CD133, natriuretic peptide receptor C (NPR3), IGFBP7) coexpressed with BAALC and common to the three entities. In T-ALL, high IGFBP7-expression was associated with an immature phenotype of early T-ALL (P<0.001), expression of CD34 (P<0.001) and CD33 (P<0.001). Moreover, high IGFBP7-expression predicted primary therapy resistance (P=0.03) and inferior survival in T-ALL (P=0.03). In vitro studies revealed that IGFBP7 protein significantly inhibited the proliferation of leukemia cell lines (Jurkat cells: 42% reduction, P=0.002; KG1a cells: 65% reduction, P<0.001). In conclusion, IGFBP7 was identified as a BAALC coexpressed gene. Furthermore, high IGFBP7 was associated with stem cell features and treatment failure in T-ALL. In contrast to BAALC, which likely represents only a surrogate marker of treatment failure in acute leukemia, IGFBP7 regulates the proliferation of leukemic cells and might be involved in chemotherapy resistance.

Immune reconstitution and cytomegalovirus infection after allogeneic stem cell transplantation: the important impact of in vivo T cell depletion

We analyzed cytomegalovirus (CMV) infection risk factors and immune reconstitution kinetics in 89 patients after allogeneic stem cell transplantation (allo-SCT). The use of alemtuzumab for in vivo T cell depletion (TCD) had, besides the donor/recipient CMV serostatus, the strongest influence on the CMV infection risk in univariate and multivariate analyses. In comparison to without use of in vivo TCD, the CMV infection risk [hazard ratio (HR)] was 4.82-fold after TCD with alemtuzumab, but only 1.40-fold after TCD with antithymocyte globulin (ATG). Alemtuzumab strongly depressed CD4(+) and CD8(+) T cell reconstitution, whereas ATG only delayed CD4(+) T cell reconstitution. Considering the reconstitution kinetics of CD4(+) and CD8(+) T cells, CMV-specific CD8(+) T cells, NK cells and the IgG concentration, only a low day +60 NK cell count (< or =161 versus >161/microl) was significantly associated with CMV infection development (HR 2.92, p = 0.034). CMV-specific CD8(+) T cells were detected in 57% of patients with a CMV-seropositive donor, but in none of the patients with a CMV-seronegative donor on day +30 (p = 0.01). Our data indicate that the type of in vivo TCD (alemtuzumab or ATG) differentially influences both the CMV infection risk and CD4(+)/CD8(+) T cell reconstitution kinetics in patients after allo-SCT.

Correlation between the incidence of nosocomial aspergillosis and room reconstruction of a haematological ward

Invasive pulmonary aspergillosis (IPA) represents ~ a major cause of morbidity and mortality in patients I with impaired function of the immune system such as in patients with acute myeloid leukaemia (AML). We investigated the in uence of the patients’ room occu- pancy and the sanitary facilities with regard to the inci- dence of IPA after reconstruction of a haematological ward. This is a retrospective cohort-control study in patients with newly diagnosed AML. Thirty ve patients were treated before and 28 patients in the time after the reconstruction works. The median time of neutropenia was 18.5 days vs. 19.5 days. Twelve patients before and 11 patients after the reconstruction developed IPA (p = 0.794). The incidence of IPA did not decrease after a reduction in the patients’ occupancy and improvement of the sanitary equipment. This study emphasises the presumed importance of optimal physical barriers, e.g. air ltration and/or antimycotic prophylaxis in high-risk patients.

Efficacy and Tolerability of Alemtuzumab (CAMPATH-1H) in the Salvage Treatment of B-Cell Chronic Lymphocytic Leukemia—Change of Regimen Needed?

We report on the response rate and tolerability of Alemtuzumab (Campath-1H) in a series of heavily pretreated patients with B-CLL with a special focus on treatment-related problems. All patients tested positive for CD52 on B-lymphocytes before entering the trial. Thirteen patients with B-chronic lymphocytic leukemia (B-CLL), 1 prolymphocytic leukemia (PLL), 1 mantle cell lymphoma (MCL) and 1 leukemic immunocytoma (IC) transformed into a high-grade NHL were included. Median age was 62 years (range 40-73), and pretreatment consisted of median 3 prior regimens (range 1-11). All patients received 3, 10 and 30 mg of Campath-1H on sequential days, and then were subsequently scheduled for 30 mg 3 times weekly. Nine out of 16 patients responded. One patient attained complete remission (CR), 8 patients achieved partial remission (PR), while 4 patients had stable disease (SD). Three patients had progressive disease (PD). Beginning with initiation of treatment recurrent profound leukopenia became evident in 13 out of 16 patients leading to treatment discontinuation. Severe nonhematological toxicity (WHO grade IV bronchospasm) occurred in the first patient of this series, who initially had no concomitant steroids. Therefore, we developed a steroid co-medication regimen for the first 4 Campath-1H applications with quick tapering thereafter. Following this regimen, no infusion associated side effects WHO grade > II were observed. Infectious complications leading to treatment discontinuation consisted of pulmonary aspergillosis in one and bacterial pneumonia in another case. One patient with refractory B-CLL and Pneumocystis carinii pneumonia plus CMV reactivation died. In summary, Campath-1H appears to be effective against leukemic low-grade B-NHL, also in advanced stage. In our series, application 3 times weekly was not possible due to hematotoxicity. We recommend, therefore, flexible time intervals depending on the leukocyte counts. Whether a cumulative dosage according to 3 x 30 mg Campath-1H for 12 weeks is needed still remains to be clarified.

Immune self-tuning in renal cell carcinoma patients

e22069

Background: Renal cell carcinoma (RCC) cells can inhibit protective antitumor immunity by secretion of immunosuppressive factors leading to the induction of regulatory T cells. The objective of this study was to investigate the prognostic impact of mRNA expression levels of IL10, TGFβ and forkhead box transcription factor (FoxP3) mRNA in peripheral blood mononuclear cells (PBMCs) of metastatic RCC patients before receiving treatment with sorafenib. Methods: PBMCs of 46 patients were assessed for their expression levels of TGFβ, IL10 and FoxP3 by quantitative RT-PCR. Clinical features considered included ECOG performance status, hemoglobin, alkaline phosphatase, and calcium concentrations. Disease evaluation was performed every 8 weeks following RECIST criteria. Relationship between pre-treatment factors and survival were examined in univariate analyses and subsequently by multivariate analysis using a stepwise Cox regression model. Results: In contrast to FoxP3, mRNA expression levels of IL10 and TGFβ were significantly higher in the 46 RCC patients compared to healthy volunteers: Median expression levels [ratio marker /housekeeping gene PBGD] were 5.56E-05 vs 2.05E-04 (P=0.034) for IL10 and 7.38E-02 vs 3.04E- 01 (P=0.023) for TGFβ. Univariate analysis revealed a negative prognostic influence of IL10 on progression free survival (p=0.04) and on overall survival, although not significant (P= 0.063). Surprisingly, high TGFβ and FoxP3 expression levels had a positive influence on progression free (P<0.001 and P=0.047, respectively) and overall survival (P<0.001 and P= 0.031, respectively). In the multivariate analysis low ECOG performance status and high TGFβ mRNA expression levels were independently associated with worse progression free (P=0.001 and P=0.054,) and worse overall survival (P=0. 006 and P< 0.001, respectively). Conclusions: RCC caused an immune-suppressive phenotype in PBMC characterized by increased mRNA expression levels of IL10 and TGFβ. Surprisingly, in contrast to IL10, a high TGFβ mRNA expression level was an independent good prognostic factor. Whether this observation can be attributed to recently described immune promoting functions of TGFβ needs to be determined.

No significant financial relationships to disclose.

CXCL13 and CXCL12 in central nervous system (CNS) lymphoma patients

2071

Background: Homing of malignant lymphocytes to the CNS may play a role in the pathogenesis of CNS lymphoma. Recently, the expression of the chemokine receptors CXCR4 and CXCR5 as well as their chemokine ligands CXCL12 and CXCL13 by tumor cells in primary CNS lymphoma (PCNSL) has been demonstrated. In this study, we evaluated CXCL12 and CXCL13 in cerebrospinal fluid (CSF) and serum of patients with CNS lymphoma. Methods: Samples from 30 patients with CNS lymphoma (23 with PCNSL and seven with secondary CNS lymphoma) and 40 controls (10 patients with other CNS malignancies and 30 without a malignant CNS disease) were examined. CXCL12 and CXCL13 concentrations were measured using enzyme-linked immunosorbent assays. The grade of blood brain barrier (BBB) disruption was estimated by the CSF/serum albumin ratio. Results: CNS lymphoma patients and controls did not differ in CXCL12 serum and CSF levels. Serum levels of CXCL13 were generally low. CXCL13 CSF levels, however, were high only in CNS lymphoma patients but not in controls (p < 0.0001). Chemokine levels in CSF and serum did not correlate. In CNS lymphoma CXCL13 concentration in CSF correlated with BBB disruption (R = 0.66, p = 0.003). Elevated CSF levels of CXCL12 and CXCL13 measured in seven CNS lymphoma patients decreased in five patients which responded to chemotherapy, and increased in two with lymphoma progression. Conclusions: Our results suggest a production of CXCL13 within the CNS of CNS lymphoma patients which decreases with response to therapy. Thus, CXCL13 may represent a marker for further diagnostic and prognostic studies.

No significant financial relationships to disclose.

Cerebral aspergillosis: tissue penetration is the key

Cerebral aspergillosis is increasingly recognized in severely immunocompromised patients and, until recently, this type of fungal infection was associated with a mortality approaching 100%. The central nervous system is a protected environment and penetration of drugs across the blood-brain barrier is mainly limited by their molecular size and physicochemical properties, as well as drug interaction with transporter systems (e.g., P-glycoprotein) at the blood-brain barrier. Most antifungal agents are large molecules (>700 Da), which makes sufficient penetration into the central nervous system unlikely. In fact, the available data indicate low levels of most antifungal agents in cerebrospinal fluid and brain tissue, except for fluconazole and voriconazole. Concentrations of voriconazole exceeding inhibitory concentrations for Aspergillus species were found repeatedly in cerebrospinal fluid and brain tissue, including brain abscess material. A recent retrospective study confirmed that voriconazole treatment resulted in improved response and survival rates in patients with cerebral aspergillosis. Data from animal models, which explored escalated doses or combinations of antifungal agents in experimental neuroaspergillosis, suggest that selected combination or dose-escalated therapies might further improve the still unsatisfactory prognosis in this particular type of Aspergillus infection.

Primary CNS lymphoma with intraocular involvement: International PCNSL Collaborative Group Report

OBJECTIVE

To describe the demographics, diagnostic details, therapeutic management, and outcome in patients with primary CNS lymphoma (PCNSL) with ocular involvement.

METHODS

A retrospective study of 221 patients was assembled from 16 centers in seven countries. Only HIV-negative, immunocompetent patients with brain and ocular lymphoma were included; none had systemic lymphoma.

RESULTS

Median age at diagnosis was 60. Fifty-seven percent were women. Median Eastern Cooperative Oncology Group performance status was 2. Ocular disturbance and behavioral/cognitive changes were the most common presenting symptoms. Diagnosis of lymphoma was made by brain biopsy (147), vitrectomy (65), or CSF cytology (11). Diagnosis of intraocular lymphoma was made by vitrectomy/choroidal/retinal biopsy (90) or clinical ophthalmic examination (141). CSF cytology was positive in 23%. Treatment information was available for 176 patients. A total of 102 received dedicated ocular therapy (ocular radiotherapy 79, intravitreal methotrexate 22, and both 1) in addition to treatment for their brain lymphoma. Sixty-nine percent progressed at a median of 13 months; sites of progression included brain 52%, eyes 19%, brain and eyes 12%, and systemic 2%. Patients treated with local ocular therapy did not have a statistically significant decreased risk of failing in the eyes (p = 0.7). Median progression free survival and overall survival for the entire cohort were 18 and 31 months.

CONCLUSION

This is the largest reported series of primary CNS lymphoma (PCNSL) with intraocular involvement. Progression free and overall survival was similar to that reported with PCNSL. Dedicated ocular therapy improved disease control but did not affect overall survival.

Meningeal dissemination in primary CNS lymphoma: prospective evaluation of 282 patients

BACKGROUND

The impact of meningeal dissemination in primary CNS lymphoma (PCNSL) is debated, and the reported frequency varies. We prospectively evaluated the diagnostic value of PCR in comparison with CSF cytomorphology and MRI for diagnosing meningeal dissemination in PCNSL.

METHODS

We evaluated 282 patients from a multicenter therapy study for PCNSL for the presence of meningeal dissemination: 205 with CSF cytomorphology, 171 with PCR of the rearranged immunoglobulin heavy-chain genes in CSF, and 217 with cranial MRI.

RESULTS

Meningeal dissemination was found in 33 of 205 patients (16%) by cytomorphology, in 19 of 171 (11%) patients evaluated by PCR, and in 8 of 217 patients (4%) by MRI. Considering either of these methods, the relative frequency of meningeal dissemination was 17.4% (49 of 282 patients). PCR was monoclonal in 6 of 19 (32%) samples with positive cytomorphology, 1 of 13 samples (8%) with suspicious cytology, and in 10 of 105 (10%) cytologically negative samples. In 11 samples with positive and 12 with suspicious cytology, PCR showed only a polyclonal pattern. The probability of meningeal dissemination detection was higher in cases with CSF pleocytosis (>5/microL) with an OR of 2.48 (95% CI 1.15-5.34, p = 0.018). CSF protein had no predictive value for meningeal dissemination detection.

CONCLUSIONS

We found a low rate of meningeal dissemination in primary CNS lymphoma in this large prospective study. The rate of discordant PCR and cytomorphologic results was high. Thus, the methods should be regarded as complementary. CSF pleocytosis had predictive value for meningeal dissemination detection.

Bendamustine, but not fludarabine, exhibits a low stem cell toxicity in vitro

PURPOSE

We investigated the in vitro toxicity of bendamustine and fludarabine to hematopoietic progenitors and stem cells from healthy donors.

METHODS

Clonogenic agar colony assays, non-clonogenic long-term liquid cultures (LTC) and apoptosis assays were used to assess the cytotoxicity of both the agents.

RESULTS

Total colony-forming units (CFU) were more sensitive to fludarabine than to bendamustine in agar colony assays (IC(50) 0.7 microM/L and 8.5 microM/L, respectively). Using the Bliss independence model and combining the two agents yielded additive inhibition of progenitors. Non-clonogenic assays, including LTC and an apoptosis assay detecting activated caspases showed that stem cells are characterized by low sensitivity to bendamustine. In contrast, fludarabine strongly inhibited the viability and growth of stem cells in LTC.

CONCLUSIONS

Our data show that bendamustine is characterized by lower in vitro toxicity to hematopoietic progenitors and stem cells than fludarabine and might thus be preferable in regimens prior to stem cells apheresis.