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Featured researches published by Jochen Fleckenstein.


Journal of Clinical Oncology | 2014

Role of Radiotherapy to Bulky Disease in Elderly Patients With Aggressive B-Cell Lymphoma

Gerhard Held; Niels Murawski; Marita Ziepert; Jochen Fleckenstein; Viola Pöschel; Carsten Zwick; Jörg Bittenbring; Mathias Hänel; Sibylla Wilhelm; Jörg Schubert; Norbert Schmitz; Markus Löffler; Christian Rübe; Michael Pfreundschuh

PURPOSE R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) is standard care for aggressive B-cell lymphoma. A prospective trial was conducted to investigate the role of additive radiotherapy (RT) to bulky and extralymphatic disease. PATIENTS AND METHODS The best arm of the RICOVER-60 trial (6×R-CHOP-14+2R [R-CHOP administered once every 2 weeks plus two additional applications of rituximab] plus involved-field RT [36 Gy] to sites of initial bulky [≥ 7.5 cm] disease and extralymphatic involvement) was compared with a cohort receiving the same immunochemotherapy but without RT in an amendment to the RICOVER-60 trial (RICOVER-noRTh) in a prospective fashion. RESULTS After a median observation time of 39 months, 164 of 166 RICOVER-noRTh patients were evaluable. In a multivariable analysis of the intention-to-treat population adjusting for International Prognostic Index risk factors and age (> 70 years), event-free survival (EFS) of patients with bulky disease was inferior without additive RT (hazard ratio [HR], 2.1; 95% CI, 1.3 to 3.5; P = .005), with trends for inferior progression-free (PFS; HR, 1.8; 95% CI, 1.0 to 3.3; P = .058) and overall survival (OS; HR, 1.6; 95% CI, 0.9 to 3.1; P = .127). In a per-protocol analysis with 11 patients in RICOVER-noRTh excluded for receiving unplanned RT, multivariable analysis revealed HRs of 2.7 (95% CI, 1.3 to 5.9; P = .011) for EFS, 4.4 (95% CI, 1.8 to 10.6; P = .001) for PFS, and 4.3 (95% CI, 1.7 to 11.1; P = .002) for OS for patients not receiving RT to bulky disease. CONCLUSION Additive RT to bulky sites abrogates bulky disease as a risk factor and improves outcome of elderly patients with aggressive B-cell lymphoma. Whether RT can be spared in patients with (metabolic) complete remission after immunochemotherapy must be addressed in appropriately designed prospective trials.


Journal of Clinical Oncology | 2013

Impact of Rituximab and Radiotherapy on Outcome of Patients With Aggressive B-Cell Lymphoma and Skeletal Involvement

Gerhard Held; Samira Zeynalova; Niels Murawski; Marita Ziepert; Barbara Kempf; Andreas Viardot; Martin Dreyling; Michael Hallek; Mathias Witzens-Harig; Jochen Fleckenstein; Christian Rübe; Carsten Zwick; Bertram Glass; Norbert Schmitz; Michael Pfreundschuh

PURPOSE To study clinical presentation, outcome, and the role of radiotherapy in patients with aggressive B-cell lymphoma and skeletal involvement treated with and without rituximab. PATIENTS AND METHODS Outcome of patients with skeletal involvement was analyzed in a retrospective study of nine consecutive prospective trials of the German High-Grade Non-Hodgkin lymphoma Study Group. RESULTS Of 3,840 patients, 292 (7.6%) had skeletal involvement. In the MabThera International Trial (MInT) for young good-prognosis patients and the Rituximab With CHOP Over 60 Years (RICOVER-60) study for elderly patients, the randomized addition of rituximab improved event-free survival (EFS; hazard ratio for MInT [HRMInT] = 0.4, P > 001; hazard ratio for RICOVER-60 [HRRICOVER-60] = 0.6, P > .001) and overall survival (OS; HRMInT = 0.4, P < .001; HRRICOVER-60 = 0.7, P = .002) in patients without skeletal involvement, but failed to improve the outcome of patients with skeletal involvement (EFS: HRMInT = 1.4, P = .444; HRRICOVER-60 = 0.8, P = .449; OS: HRMInT = 0.6, P = .449; HRRICOVER-60 = 1.0, P = .935). Skeletal involvement was associated with a worse outcome after cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) plus rituximab (HREFS = 1.5, P = .048; HROS = 1.1; P = .828), but not after CHOP without rituximab (HREFS = 0.8, P = .181; HROS = 0.7, P = .083). In contrast to rituximab, additive radiotherapy to sites of skeletal involvement was associated with a decreased risk (HREFS = 0.3, P = .001; HROS = 0.5; P = .111). CONCLUSION Rituximab failed to improve the outcome of patients with diffuse large B-cell lymphoma with skeletal involvement, although our data suggest a beneficial effect of radiotherapy to sites of skeletal involvement. Whether radiotherapy to sites of skeletal involvement can be spared in cases with a negative positron emission tomography after immunochemotherapy should be addressed in appropriately designed prospective trials.


International Journal of Radiation Oncology Biology Physics | 2010

DNA Repair Alterations in Children With Pediatric Malignancies: Novel Opportunities to Identify Patients at Risk for High-Grade Toxicities

Claudia E. Rübe; Andreas Fricke; Ruth Schneider; Karin Simon; Martin Kühne; Jochen Fleckenstein; Stefan Gräber; Norbert Graf; Christian Rübe

PURPOSE To evaluate, in a pilot study, the phosphorylated H2AX (γH2AX) foci approach for identifying patients with double-strand break (DSB) repair deficiencies, who may overreact to DNA-damaging cancer therapy. METHODS AND MATERIALS The DSB repair capacity of children with solid cancers was analyzed compared with that of age-matched control children and correlated with treatment-related normal-tissue responses (n = 47). Double-strand break repair was investigated by counting γH2AX foci in blood lymphocytes at defined time points after irradiation of blood samples. RESULTS Whereas all healthy control children exhibited proficient DSB repair, 3 children with tumors revealed clearly impaired DSB repair capacities, and 2 of these repair-deficient children developed life-threatening or even lethal normal-tissue toxicities. The underlying mutations affecting regulatory factors involved in DNA repair pathways were identified. Moreover, significant differences in mean DSB repair capacity were observed between children with tumors and control children, suggesting that childhood cancer is based on genetic alterations affecting DSB repair function. CONCLUSIONS Double-strand break repair alteration in children may predispose to cancer formation and may affect childrens susceptibility to normal-tissue toxicities. Phosphorylated H2AX analysis of blood samples allows one to detect DSB repair deficiencies and thus enables identification of children at risk for high-grade toxicities.


PLOS ONE | 2008

Cytokine Plasma Levels: Reliable Predictors for Radiation Pneumonitis?

Claudia E. Rübe; Jan Palm; Michael Erren; Jochen Fleckenstein; Jochem König; Klaus Remberger; Christian Rübe

Background Radiotherapy (RT) is the primary treatment modality for inoperable, locally advanced non-small-cell lung cancer (NSCLC), but even with highly conformal treatment planning, radiation pneumonitis (RP) remains the most serious, dose-limiting complication. Previous clinical reports proposed that cytokine plasma levels measured during RT allow to estimate the individual risk of patients to develop RP. The identification of such cytokine risk profiles would facilitate tailoring radiotherapy to maximize treatment efficacy and to minimize radiation toxicity. However, cytokines are produced not only in normal lung tissue after irradiation, but are also over-expressed in tumour cells of NSCLC specimens. This tumour-derived cytokine production may influence circulating plasma levels in NSCLC patients. The aim of the present study was to investigate the prognostic value of TNF-α, IL-1β, IL-6 and TGF-β1 plasma levels to predict radiation pneumonitis and to evaluate the impact of tumour-derived cytokine production on circulating plasma levels in patients irradiated for NSCLC. Methodology/Principal Findings In 52 NSCLC patients (stage I–III) cytokine plasma levels were investigated by ELISA before and weekly during RT, during follow-up (1/3/6/9 months after RT), and at the onset of RP. Tumour biopsies were immunohistochemically stained for IL-6 and TGF-β1, and immunoreactivity was quantified (grade 1–4). RP was evaluated according to LENT-SOMA scale. Tumour response was assessed according to RECIST criteria by chest-CT during follow-up. In our clinical study 21 out of 52 patients developed RP (grade I/II/III/IV: 11/3/6/1 patients). Unexpectedly, cytokine plasma levels measured before and during RT did not correlate with RP incidence. In most patients IL-6 and TGF-β1 plasma levels were already elevated before RT and correlated significantly with the IL-6 and TGF-β1 production in corresponding tumour biopsies. Moreover, IL-6 and TGF-β1 plasma levels measured during follow-up were significantly associated with the individual tumour responses of these patients. Conclusions/Significance The results of this study did not confirm that cytokine plasma levels, neither their absolute nor any relative values, may identify patients at risk for RP. In contrast, the clear correlations of IL-6 and TGF-β1 plasma levels with the cytokine production in corresponding tumour biopsies and with the individual tumour responses suggest that the tumour is the major source of circulating cytokines in patients receiving RT for advanced NSCLC.


International Journal of Radiation Oncology Biology Physics | 2011

F-18-FDG-PET Confined Radiotherapy of Locally Advanced NSCLC With Concomitant Chemotherapy: Results of the PET-PLAN Pilot Trial

Jochen Fleckenstein; Dirk Hellwig; Stephanie Kremp; Aleksandar Grgic; Andreas Gröschel; Carl-Martin Kirsch; Ursula Nestle; Christian Rübe

PURPOSE The integration of fluoro-deoxy-D-glucose positron emission tomography (FDG-PET) in the process of radiotherapy (RT) planning of locally advanced non-small-cell lung cancer (NSCLC) may improve diagnostic accuracy and minimize interobserver variability compared with target volume definition solely based on computed tomography. Furthermore, irradiating only FDG-PET-positive findings and omitting elective nodal regions may allow dose escalation by treating smaller volumes. The aim of this prospective pilot trial was to evaluate the therapeutic safety of FDG-PET-based RT treatment planning with an autocontour-derived delineation of the primary tumor. METHODS AND MATERIALS Eligible patients had Stages II-III inoperable NSCLC, and simultaneous, platinum-based radiochemotherapy was indicated. FDG-PET and computed tomography acquisitions in RT treatment planning position were coregistered. The clinical target volume (CTV) included the FDG-PET-defined primary tumor, which was autodelineated with a source-to-background algorithm, plus FDG-PET-positive lymph node stations. Limited by dose restrictions for normal tissues, prescribed total doses were in the range of 66.6 to 73.8 Gy. The primary endpoint was the rate of out-of-field isolated nodal recurrences (INR). RESULTS As per intent to treat, 32 patients received radiochemotherapy. In 15 of these patients, dose escalation above 66.6 Gy was achieved. No Grade 4 toxicities occurred. After a median follow-up time of 27.2 months, the estimated median survival time was 19.3 months. During the observation period, one INR was observed in 23 evaluable patients. CONCLUSIONS FDG-PET-confined target volume definition in radiochemotherapy of NSCLC, based on a contrast-oriented source-to-background algorithm, was associated with a low risk of INR. It might provide improved tumor control because of dose escalation.


International Journal of Radiation Oncology Biology Physics | 2011

THE IMPACT OF INDIVIDUAL IN VIVO REPAIR OF DNA DOUBLE-STRAND BREAKS ON ORAL MUCOSITIS IN ADJUVANT RADIOTHERAPY OF HEAD-AND-NECK CANCER

Jochen Fleckenstein; Martin Kühne; Katharina Seegmüller; Sarah Derschang; Patrick Melchior; Stefan Gräber; Andreas Fricke; Claudia E. Rübe; Christian Rübe

PURPOSE To evaluate the impact of individual in vivo DNA double-strand break (DSB) repair capacity on the incidence of severe oral mucositis in patients with head-and-neck cancer undergoing adjuvant radiotherapy (RT) or radiochemotherapy (RCT). PATIENTS AND METHODS Thirty-one patients with resected head-and-neck cancer undergoing adjuvant RT or RCT were examined. Patients underwent RT of the primary tumor site and locoregional lymph nodes with a total dose of 60-66 Gy (single dose 2 Gy, five fractions per week). Chemotherapy consisted of two cycles of cisplatin and 5-fluorouracil. To assess DSB repair, γ-H2AX foci in blood lymphocytes were quantified before and 0.5 h, 2.5 h, 5 h, and 24 h after in vivo radiation exposure (the first fraction of RT). World Health Organization scores for oral mucositis were documented weekly and correlated with DSB repair. RESULTS Sixteen patients received RT alone; 15 patients received RCT. In patients who developed Grade≥3 mucositis (n=18) the amount of unrepaired DSBs 24 h after radiation exposure and DSB repair half-times did not differ significantly from patients with Grade≤2 mucositis (n=13). Patients with a proportion of unrepaired DSBs after 24 h higher than the mean value + one standard deviation had an increased incidence of severe oral mucositis. CONCLUSIONS Evaluation of in vivo DSB repair by determination of γ-H2AX foci loss is feasible in clinical practice and allows identification of patients with impaired DSB repair. The incidence of oral mucositis is not closely correlated with DSB repair under the evaluated conditions.


Radiation Oncology | 2011

Toxicity after radiochemotherapy for glioblastoma using temozolomide - a retrospective evaluation

Marcus Niewald; Christian Berdel; Jochen Fleckenstein; Norbert Licht; Ralf Ketter; Christian Rübe

PurposeRetrospective evaluation of toxicity and results after radiochemotherapy for glioblastoma.Methods46 patients with histopathologically proven glioblastoma received simultaneous radiochemotherapy (RCT). The mean age at the beginning of therapy was 59 years, the mean Karnofsky performance index 80%. 44 patients had been operated on before radiotherapy, two had not. A total dose of 60 Gy was applied in daily single fractions of 2.0 Gy within six weeks, 75 mg/m2/day Temozolomide were given orally during the whole radiotherapy period.ResultsA local progression could be diagnosed in 34/46 patients (70%). The median survival time amounted to 13.6 months resulting in one-year and two-year survival probabilities of 48% and 8%, respectively.Radiotherapy could be applied completely in 89% of the patients. Chemotherapy could be completed according to schedule only in 56.5%, the main reason being blood toxicity (50% of the interruptions). Most of those patients suffered from leucopenia and/or thrombopenia grade III and IV CTC (Common toxicity criteria). Further reasons were an unfavourable general health status or a rise of liver enzymes.The mean duration of thrombopenia and leucopenia amounted to 64 and 20 days. In two patients, blood cell counts remained abnormal until death. In two patients we noticed a rise of liver enzymes. In one of these in the healing phase of hepatitis a rise of ASAT and ALAT CTC grade IV was diagnosed. These values normalized after termination of temozolomide medication. One patient died of pneumonia during therapy.ConclusionOur survival data were well within the range taken from the literature. However, we noticed a considerable frequency and intensity of side effects to bone marrow and liver. These lead to the recommendations that regular examinations of blood cell count and liver enzymes should be performed during therapy and temozolomide should not be applied or application should be terminated according to the criteria given by the manufacturer.


Blood | 2014

The role of radiotherapy and intrathecal CNS prophylaxis in extralymphatic craniofacial aggressive B-cell lymphomas

Niels Murawski; Gerhard Held; Marita Ziepert; Barbara Kempf; Andreas Viardot; Mathias Hänel; Mathias Witzens-Harig; Rolf Mahlberg; Christian Rübe; Jochen Fleckenstein; Carsten Zwick; Bertram Glass; Norbert Schmitz; Samira Zeynalova; Michael Pfreundschuh

To define the role of radiotherapy and intrathecal prophylaxis in extralymphatic craniofacial involvement (ECFI) of aggressive B-cell lymphoma, we analyzed 11 consecutive German High-Grade Non-Hodgkin Lymphoma Study Group trials. ECFI occurred in 290/4155 (7.0%) patients (orbita, 31; paranasal sinuses, 93; main nasal cavity, 38; tongue, 27; remaining oral cavity, 99; salivary glands, 54). In a multivariable analysis adjusted for International Prognostic Index rituximab improved event-free and overall survival both in patients with and without ECFI. Three-year event-free (79% vs 79%; P = .842) and overall survival (86% vs 88%; P = .351) rates were similar in 145 patients receiving and 57 not receiving radiotherapy. Without rituximab, the 2-year cumulative rate of central nervous system (CNS) disease was increased in 205 ECFI patients compared with 2586 non-ECFI patients (4.2% vs 2.8%; P = .038), whereas this was not observed with rituximab (1.6% in 83 ECFI vs 3.4% in 1252 non-ECFI patients; P = .682). In 88 ECFI patients who received intrathecal prophylaxis with methotrexate, the 2-year rate of CNS disease was 4.2% compared with 2.3% in 191 patients who did not (P = .981). In conclusion, rituximab eliminates the increased risk for CNS disease in patients with ECFI. This retrospective analysis does not support intrathecal prophylaxis or radiotherapy to ECFI patients in complete remission/unconfirmed complete remission. These findings should be confirmed in a prospective study.


The Journal of Nuclear Medicine | 2009

Nonrigid Versus Rigid Registration of Thoracic 18F-FDG PET and CT in Patients with Lung Cancer: An Intraindividual Comparison of Different Breathing Maneuvers

Aleksandar Grgic; Ursula Nestle; Andrea Schaefer-Schuler; Stephanie Kremp; Elena Ballek; Jochen Fleckenstein; Christian Rübe; Carl-Martin Kirsch; Dirk Hellwig

In lung cancer, 18F-FDG PET, CT, and 18F-FDG PET/CT are used for noninvasive staging and therapy planning. Even with improved image registration techniques—especially in the modern hybrid PET/CT scanners—inaccuracies in the fusion process may occur, leading to errors in image interpretation. The aim of this study was to investigate by an intraindividual analysis whether, in comparison with a rigid algorithm, a nonrigid registration algorithm improves the quality of fusion between 18F-FDG PET and CT. Methods: Sixteen patients with histologically proven non–small cell lung cancer underwent a thoracic 18F-FDG PET acquisition in radiotherapy treatment position and 3 CT acquisitions (expiration, inspiration, and mid breath-hold) on the same day. All scans were registered with rigid and nonrigid procedures, resulting in 6 fused datasets: rigid inspiration, rigid expiration, rigid mid breath-hold, nonrigid inspiration, nonrigid expiration, and nonrigid mid breath-hold. The quality of alignment was assessed by 3 experienced readers at 8 anatomic landmarks: lung apices, aortic arch, heart, spine, sternum, carina, diaphragm, and tumor using an alignment score ranging from 1 (no alignment) to 5 (exact alignment). Results: Nonrigid PET/CT showed better alignment than rigid PET/CT (3.5 ± 0.7 vs. 3.3 ± 0.7, P < 0.001). Regarding the breathing maneuver, no difference between nonrigid mid breath-hold and rigid mid breath-hold was observed. In contrast, the alignment quality significantly improved from rigid expiration to nonrigid expiration (3.4 ± 0.7 vs. 3.6 ± 0.7, P < 0.001) and from rigid inspiration to nonrigid inspiration (3.1 ± 0.7 vs. 3.3 ± 0.7, P < 0.001). With regard to individual landmarks, an improvement in fusion quality through the use of nonrigid registration was obvious at the lung apices, carina, and aortic arch. Conclusion: The alignment quality of thoracic 18F-FDG PET/CT exhibits a marked dependence on the breathing maneuver performed during the CT acquisition, as demonstrated in an intraindividual comparison. Nonrigid registration is a significant improvement over rigid registration if the CT is performed during full inspiration or full expiration. The best fusion results are obtained with the CT performed at mid breath-hold using rigid registration, without an improvement using nonrigid algorithms.


Radiation Oncology | 2009

Intraoperative radiotherapy (IORT) combined with external beam radiotherapy (EBRT) for soft-tissue sarcomas – a retrospective evaluation of the Homburg experience in the years 1995–2007

Marcus Niewald; Jochen Fleckenstein; Norbert Licht; Caroline Bleuzen; Christian Ruebe

PurposeTo retrospectively evaluate the results after a regimen of surgery, IORT (intraoperative radiotherapy), and EBRT (external beam radiotherapy) for soft-tissue sarcomasMethods38 consecutive patients underwent IORT for soft-tissue sarcoma; 29 were treated for primary tumours, 9 for recurrences. There were 14 cases with liposarcomas, 8 with leiomyosarcomas, 7 with malignant fibrous histiocytomas. 27/38 tumours were located in the extremities, the remaining ones in the retroperitoneum or the chest. Radical resection was attempted in all patients; a R0-resection was achieved in 15/38 patients, R1 in 12/38 pats and R2 in 4/38 pats. IORT was performed using a J-125 source and a HDR (high dose rate) afterloading machine after suturing silicone flaps to the tumour bed. The total dose applied ranged from 8–15 Gy/0.5 cm tissue depth measured from the flap surface. After wound healing external beam radiotherapy (EBRT) was applied in 31/38 patients with total doses of 23–56 Gy dependent on resection status and wound situation. The mean duration of follow-up was 2.3 years.ResultsA local recurrence was found in 10/36 patients, lymph node metastases in 2/35, and distant metastases in 6/35 patients. The actuarial local control rate was 63%/5 years. The overall survival rate was 57%/5 years. There was no statistically significant difference between the results after treatment for primaries or for recurrences. Late toxicity to the skin was found in 13/31 patients, wound healing problems in 5/31 patients. A neuropathy was never seen.ConclusionThe combination of surgery, IORT, and EBRT yields favourable local control and survival data which are well within the range of the results reported in the literature. The complication rates, however, are considerable although the complications are not severe, they should be taken into account when therapy decisions are made.

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