ALBERT

Description: Residual mediastinal masses are frequently observed in patients with Hodgkin disease (HD) after completed therapy, and the discrimination between active tumor tissue and fibrotic residues remains a clinical challenge. We studied the diagnostic value of metabolic imaging by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in detecting active mediastinal disease and predicting relapse. Twenty-eight HD patients with a residual mediastinal mass of at least 2 cm after initial therapy or after salvage chemotherapy were prospectively assigned to 29 examinations with FDG PET and were evaluated as 29 “subjects.” Patients were monitored for at least 1 year after examination and observed for signs of relapse. Median follow-up was 28 months (range, 16 to 68 months). A PET-negative mediastinal tumor was observed in 19 subjects, of whom 16 stayed in remission and 3 relapsed. Progression or relapse occurred in 6 of 10 subjects with a positive PET, whereas 4 subjects remained in remission. The negative predictive value (negative PET result and remission) at 1 year was 95%, and the positive predictive value (positive PET result and relapse) was 60%. The disease-free survival for PET-negative and PET-positive patients at 1 year was 95% and 40%, respectively. The difference was statistically significant. A negative FDG PET indicates that an HD patient with a residual mediastinal mass is unlikely to relapse before 1 year, if ever. On the other hand, a positive PET result indicates a significantly higher risk of relapse and demands further diagnostic procedures and a closer follow-up.

Description: Residual mediastinal masses are frequently observed in patients with Hodgkin disease (HD) after completed therapy, and the discrimination between active tumor tissue and fibrotic residues remains a clinical challenge. We studied the diagnostic value of metabolic imaging by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in detecting active mediastinal disease and predicting relapse. Twenty-eight HD patients with a residual mediastinal mass of at least 2 cm after initial therapy or after salvage chemotherapy were prospectively assigned to 29 examinations with FDG PET and were evaluated as 29 “subjects.” Patients were monitored for at least 1 year after examination and observed for signs of relapse. Median follow-up was 28 months (range, 16 to 68 months). A PET-negative mediastinal tumor was observed in 19 subjects, of whom 16 stayed in remission and 3 relapsed. Progression or relapse occurred in 6 of 10 subjects with a positive PET, whereas 4 subjects remained in remission. The negative predictive value (negative PET result and remission) at 1 year was 95%, and the positive predictive value (positive PET result and relapse) was 60%. The disease-free survival for PET-negative and PET-positive patients at 1 year was 95% and 40%, respectively. The difference was statistically significant. A negative FDG PET indicates that an HD patient with a residual mediastinal mass is unlikely to relapse before 1 year, if ever. On the other hand, a positive PET result indicates a significantly higher risk of relapse and demands further diagnostic procedures and a closer follow-up.

Description: Abstract 3832 Introduction. VSCO.NET, the Virtual Society of Clinical Oncology was founded as an independent internet platform for healthcare professionals working in the field of hematology and oncology. The aim is to bundle all accessible knowledge and experience of the oncology community in one place and to grant an open, free-of-charge source of information. Methods. The concept was developed by hematologists/oncologists and was realized together with a team of web programmers. The software was developed in HTML, PHP and JavaScript and runs on a Linux web-server. To enable an internationally accepted platform, VSCO.NET offers its pages in English, Spanish, French and German. Results. VSCO.NET went public in December 2009 in a beta-stage with the following functions: 1. a comprehensive chemotherapy order system with over 100 included chemotherapy protocols, 2. staging tools for Hodgkin's and Non-Hodgkin's lymphoma, multiple myeloma, CLL, and CML, 3. texts and tools for oncological emergencies, 4. a knowledge database/file repository for information texts, presentations and pictures, 5. a news channel with oncological abstracts, and 6. a virtual tumor board (discussion forum). Currently, over 400 physicians, mostly hematologists/oncologists, have registered with VSCO.NET. The most frequented tool is ChemoBOS, the chemotherapy order system, which quickly generates chemotherapy orders for patients. Due to its open and free protocol template generator, many physicians have created their own adapted chemotherapy protocols, which can be used by the entire VSCO.NET community. Also, the staging tools were generally well accepted and have a fairly high usage. However, the virtual tumor board as a way to communicate about difficult cases has not been used so far, which could show a reluctance of physicians to discuss their patient cases in an internet-based forum. It should be noted that many physicians registered from developing countries, who cannot afford expensive chemotherapy software and now have the opportunity to improve patient care at their centers. Conclusions: As the first internet-based society for hematology/oncology with a wide variety of interactive functions, VSCO.NET shows great potential to internationally connect physicians, expand the accessibility of oncological knowledge and to facilitate the daily clinical routine. Disclosures: No relevant conflicts of interest to declare.

Description: In solid tumors, leukemias, and lymphomas, increased frequencies of functional CD4+CD25high regulatory T cells (Treg cells) have been previously demonstrated. In healthy individuals, Treg cells consist not only of memory but also of naive T cells, which can undergo peripheral expansion and are characterized by a relative enrichment for autoreactive T-cell receptors. Here, we demonstrate in patients with premalignant monoclonal gammopathy of undetermined significance and patients with multiple myeloma that functional FoxP3+ Treg cells of naive, central, and effector memory phenotype as determined by CCR7 and CD45RA expression are significantly expanded. Low frequencies of T-cell receptor excision circles in naive Treg cells in both healthy controls and multiple myeloma patients point to peripheral expansion as the prominent mechanism of increased frequencies of naive Treg cells in these cancer patients. These findings strongly suggest that the increase of functional Treg cells in cancer patients is a response to the process of malignant transformation.

Description: Abstract 4730 Background The DNA-based immunomodulator MGN1703 stimulates the innate and cellular immune system mainly via the TLR9-receptor. The results of the recent in vivo experiments showed potent anti-tumor efficacy of MGN1703 in several mouse tumor models in prophylactic and therapeutic settings as well as a good safety profile in various animals. Two investigator-initiated pilot trials of MGN1703 as adjuvant in patients with metastatic solid tumors also showed good safety and tolerability of the drug as well as a positive effect on the response rate in patients treated with MGN1703. Patients/Methods In this Phase 1 clinical trial MGN1703 is administered subcutaneously in escalating doses (0.25 mg, 2 mg, 10 mg, 30 mg, and 60 mg; 3-6 patients per group) either in a single or in a multiple (2x / week over 6 weeks) dose regimen. Patients with metastatic tumors of the following entities are recruited for the study, if no other standard treatment options are available: Colorectal cancer, breast cancer, lung cancer, renal cell carcinoma and melanoma. Primary endpoints are evaluation of the safety and tolerability of escalating single doses and of escalating multiple doses of s.c. administered MGN1703, determination of the maximum tolerated dose (MTD) and dose limiting toxicity (DLT), and recommendation of a dose for a Phase 2 trial in patients. Results Currently, 12 patients have been treated and evaluated in the single dose groups of 0.25 mg, 2 mg, 10 mg and 30 mg (3 patients each). In the multiple dose group, 4 patients have been treated with 0.25 mg, 3 patients with 2 mg, 3 patients with 10 mg and 3 patients with 30 mg MGN1703, so far. Therapy was well tolerated except for sporadic transient symptoms as mild redness and induration of injection sites in two patients, increase of temperature to 38 °C in one patient, and fatigue in two patients. In the 0.25 mg group, one patient showed a stable disease (SD, according to RECIST) after 6 weeks of treatment, and in the 2 mg group, 3 of 3 patients showed a SD after 6 weeks. Treatment results of the last 2 dosing groups are pending. The four patients, who responded to the treatment with MGN1703, were treated with MGN1703 for further 6 weeks within an extension phase of this clinical trial. Two of them still had a SD after 12 weeks of treatment. Conclusions MGN1703 showed safety and tolerability at dosages up to 30 mg so far. The detailed evaluation of clinical and immunological responses is still ongoing. There has been no DLT at this point of the Phase 1 trial. Disclosures: Weihrauch: MOLOGEN AG: Membership on an entity's Board of Directors or advisory committees. Schmidt:MOLOGEN AG: Employment. Tschaika:MOLOGEN AG: Employment. Wittig:MOLOGEN AG: Membership on an entity's Board of Directors or advisory committees.