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result(s) for
"Bostel, Tilman"
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Pediatric craniospinal irradiation with a short partial-arc VMAT technique for medulloblastoma tumors in dosimetric comparison
by
Akbaba, Sati
,
Karle, Heiko
,
Stockinger, Marcus
in
Biomedical and Life Sciences
,
Biomedicine
,
Brain cancer
2020
Background
This study aimed to contrast four different irradiation methods for pediatric medulloblastoma tumors in a dosimetric comparison regarding planning target volume (PTV) coverage and sparing of organs at risk (OARs).
Methods
In sum 24 treatment plans for 6 pediatric patients were realized. Besides the clinical standard of a 3D-conformal radiotherapy (3D-CRT) treatment plan taken as a reference, volumetric modulated arc therapy (VMAT) treatment plans (“VMAT_AVD” vs. “noAVD” vs. “FullArc”) were optimized and calculated for each patient. For the thoracic and abdominal region, the short partial-arc VMAT_AVD technique uses an arc setup with reduced arc-length by 100°, using posterior and lateral beam entries. The noAVD uses a half 180° (posterior to lateral directions) and the FullArc uses a full 360° arc setup arrangement. The prescription dose was set to 35.2 Gy.
Results
We identified a more conformal dose coverage for PTVs and a better sparing of OARs with used VMAT methods. For VMAT_AVD mean dose reductions in organs at risk can be realized, from 16 to 6.6 Gy, from 27.1 to 8.7 Gy and from 8.0 to 1.9 Gy for the heart, the thyroid and the gonads respectively, compared to the 3D-CRT treatment method. In addition we have found out a superiority of VMAT_AVD compared to the noAVD and FullArc trials with lower exposure to low-dose radiation to the lungs and breasts.
Conclusions
With the short partial-arc VMAT_AVD technique, dose exposures to radiosensitive OARS like the heart, the thyroid or the gonads can be reduced and therefore, maybe the occurrence of late sequelae is less likely. Furthermore the PTV conformity is increased. The advantages of the VMAT_AVD have to be weighed against the potentially risks induced by an increased low dose exposure compared to the 3D-CRT method.
Journal Article
Local response and pathologic fractures following stereotactic body radiotherapy versus three-dimensional conformal radiotherapy for spinal metastases - a randomized controlled trial
by
Sprave, Tanja
,
Verma, Vivek
,
Schlampp, Ingmar
in
Aged
,
Analysis
,
Biomedical and Life Sciences
2018
Background
This was a prespecified secondary analysis of a randomized trial, which analyzed bone density following stereotactic body radiotherapy (SBRT) versus conventional three-dimensional conformal radiotherapy (3DCRT) as part of palliative management of painful spinal metastases.
Methods
Fifty-five patients were enrolled in this single-institutional randomized exploratory trial (NCT02358720). Participants were randomly assigned to receive SBRT (single-fraction 24 Gy) or 3DCRT (30 Gy/10 fractions). Quantitative bone density was evaluated at baseline, 3 and 6 months in both irradiated and unirradiated spinal bodies, along with rates of pathologic fractures and vertebral compression fractures.
Results
As compared to baseline, bone density became significantly higher at 3 and 6 months following SBRT by a median of 33.8% and 72.1%, respectively (
p
< 0.01 for both). These figures in the 3DCRT cohort were 32.9% and 41.2%, respectively (
p
< 0.01 for both). There were no statistical differences in bone density between SBRT and 3DCRT at 3 (
p
= 0.629) or 6 months (
p
= 0.327). Subgroup analysis of osteolytic metastases showed an increase in bone density relative to baseline in the SBRT (but not 3DCRT) arm. Bone density in unaffected vertebrae did not show substantial changes in either group. The 3-month incidence of new pathological fractures was 8.7% in the SBRT arm vs. 4.3% in the 3DCRT arm.
Conclusions
Despite high ablative doses in the SBRT arm, the significant increase in bone density after 3 and 6 months was similar to that of 3DCRT. Our trial demonstrated a moderate rate of subsequent pathological fracture after SBRT. Future randomized investigations with larger sample sizes are recommended.
Trial registration
www.clinicaltrials.gov
:
NCT02358720
on 9nd of February 2015.
Journal Article
Adjuvant chemoradiotherapy in elderly patients with head and neck cancer: a monoinstitutional, two-to-one pair-matching analysis
by
Wenzel, Witali Dr
,
Schmidberger Heinz Univ-Prof Dr med
,
Bostel Tilman PD Dr med
in
Alcohol abuse
,
Cancer
,
Chemotherapy
2022
PurposeAbout one fifth of patients with head and neck cancer are aged 70 years and older at the time of diagnosis. In these patients, risk factors (R1 status or extracapsular extension of lymph node metastases, ECE) often lead to a need for combined chemoradiotherapy (CRT) in the postoperative setting. However, there is considerable concern about the toxicity of such therapy in this age group.MethodsRetrospective evaluation of the data of 53 patients ≥ 70 years of age who underwent surgery in our hospital between 1999 and 2015 for tumors of the oral cavity, the oropharynx, the hypopharynx, or the larynx, who subsequently received adjuvant radiation therapy. Two younger patients (< 70 years) were assigned to each of the elderly patients in a matching procedure based on anatomic sublocalization and tumor stage. The total cohort was comprised of 154 patients.ResultsUnivariate analyses revealed a statistically significant influence of many factors on overall survival (OS) and progression-free survival (PFS), including Karnofsky performance score (KPS), alcohol consumption, smoking, R status, ECE, chemotherapy, and discontinuation of RT. Younger patients had better OS and PFS compared to the elderly (p = 0.013 and 0.012, respectively). In a multivariate Cox regression, no independent influence of age on OS and PFS was found. Survival was primarily dependent on the addition of chemotherapy to radiotherapy (RT), application of the full course of RT, continued alcohol abuse, KPS, and the presence of ECE. Toxicity analysis showed a higher incidence of chronic renal failure but, generally, side effects for elderly patients were not substantially greater.ConclusionPerformance status and behavioral risk factors but not chronological age are crucial for the prognosis of patients who require adjuvant chemoradiation.
Journal Article
Multicenter analysis on the value of standard (chemo)radiotherapy in elderly patients with locally advanced adenocarcinoma of the esophagus or gastroesophageal junction
by
Kaufmann, Justus
,
Grosu, Anca-Ligia
,
Nikolaidou, Eirini
in
Adenocarcinoma
,
Adenocarcinoma - therapy
,
Adjuvant treatment
2024
Background
To assess the tolerability and oncological results of chemoradiation in elderly patients with locally advanced adenocarcinoma of the esophagus or gastroesophageal junction.
Methods
This multi-center retrospective analysis included 86 elderly patients (≥ 65 years) with esophageal or gastroesophageal junction adenocarcinoma (median age 73 years; range 65–92 years) treated with definitive or neoadjuvant (chemo)radiotherapy. The treatment was performed at 3 large comprehensive cancer centers in Germany from 2006 to 2020. Locoregional control (LRC), progression-free survival (PFS), distant metastasis-free survival (DMFS), overall survival (OS), and treatment-associated toxicities according to CTCAE criteria v5.0 were analyzed, and parameters potentially relevant to patient outcomes were evaluated.
Results
Thirty-three patients (38%) were treated with neoadjuvant chemoradiation followed by surgery, while the remaining patients received definitive (chemo)radiation. The delivery of radiotherapy without dose reduction was possible in 80 patients (93%). In 66 patients (77%), concomitant chemotherapy was initially prescribed; however, during the course of therapy, 48% of patients (n = 32) required chemotherapy de-escalation due to treatment-related toxicities and comorbidities. Twenty-nine patients (34%) experienced higher-grade acute toxicities and 14 patients (16%) higher-grade late toxicities. The 2-year LRC, DMFS, PFS, and OS amounted to 72%, 49%, 46%, and 52%, respectively. In multivariate analysis, neoadjuvant chemoradiation followed by surgery was shown to be associated with significantly better PFS (p = 0.006), DMFS (p = 0.006), and OS (p = 0.004) compared with all non-surgical treatments (pooled definitive radiotherapy and chemoradiation). No such advantage was seen over definitive chemoradiation. The majority of patients with neoadjuvant therapy received standard chemoradiotherapy without dose reduction (n = 24/33, 73%). In contrast, concurrent chemotherapy was only possible in 62% of patients undergoing definitive radiotherapy (n = 33/53), and most of these patients required dose-reduction or modification of chemotherapy (n = 23/33, 70%).
Conclusions
In our analysis, omission of chemotherapy or adjustment of chemotherapy dose during definitive radiotherapy was necessary for the overwhelming majority of elderly esophageal cancer patients not eligible for surgery, and hence resulted in reduced PFS and OS. Therefore, optimization of non-surgical approaches and the identification of potential predictive factors for safe administration of concurrent chemotherapy in elderly patients with (gastro)esophageal adenocarcinoma is required.
Journal Article
Linear accelerator-based stereotactic fractionated photon radiotherapy as an eye-conserving treatment for uveal melanoma
2018
Background
The purpose of this retrospective analysis is to analyze clinical outcome, visual acuity and enucleation rates after linear accelerator-based stereotactic fractionated photon radiotherapy for primary uveal melanoma.
Methods
Twenty-four patients with primary uveal melanoma treated at the Department of Radiation and Oncology of the University Hospital Heidelberg between 1991 and 2015 were analyzed regarding survival and treatment-related toxicity including eye- and sight-preservation.
Results
Photon radiotherapy (RT) offered good overall local control rates with a local progression-free survival (LPFS) of 82% after 5 years and a median LPFS of 5.5 years at a median follow-up time of 5.2 years. Gender had a significant impact on LPFS yielding a mean LPFS of 8.1 years for women and 8.7 years for men (
p = 0.04
). Of all local progressions, 80% occurred within the first 5 years after RT. In one case, enucleation as final therapy option was necessary. Enucleation-free survival (EFS) was related to the radiotherapy dose (
p < 0.0001
). Thus, higher prescribed doses led to a significantly higher enucleation rate. T-stage had no significant impact on EFS, but affected the enucleation rate (
p = 0.01
). The overall survival (OS) rate was 100% after 2 years and 70% after 5 years with a median OS of 5.75 years. Age (
p = 0.046
), T stage (
p = 0.019
), local control rate (
p = 0.041
) and the time between diagnosis and the first radiation session (
p = 0.01
) had a significant effect on OS. Applied biologically effective dose (BED) did not significantly influence OS or PFS. A 2-year sight preservation rate of 75% could be achieved. In all patients, irradiation could be applied safely without any interruptions due to side effects. Six significant late toxicities with consequential blindness could be observed, making a secondary enucleation necessary in four patients. An impairment of visual acuity due to chronic optic nerve atrophy was identified in five patients within 2 years after treatment.
Conclusions
Linear accelerator-based stereotactic fractionated photon radiotherapy is an effective method in the treatment of uveal melanoma with excellent local control rates and a 2-year vision retention rate comparable to brachytherapy (BRT) or proton beam radiotherapy, even available in small centers and easy to implement. Interdisciplinary decision making is necessary to guarantee best treatment for every patient.
Journal Article
High-dose carbon-ion based radiotherapy of primary and recurrent sacrococcygeal chordomas: long-term clinical results of a single particle therapy center
by
Sprave, Tanja
,
Welzel, Thomas
,
Akbaba, Sati
in
Biomedical and Life Sciences
,
Biomedicine
,
Cancer Research
2020
Background
This study aimed to analyze the oncological long-term results and late toxicity of carbon ion-based radiotherapy (RT) of patients with sacral chordoma and to identify potential prognostic factors for local control (LC) and overall survival (OS).
Methods
A total of 68 patients with sacral chordoma treated at the Heidelberg Ion Beam Therapy Center were included in this study. Of these 52 patients (77%) received a primary RT and 16 patients (23%) received a RT in a recurrent situation. All patients were treated with carbon ion RT (CIRT), either in combination with photons (
n
= 22; 32%) or as a monotherapy (
n
= 46; 68%), with a median radiation dose of 66 Gy RBE (range 60–74 Gy). In 40 patients (59%), RT was performed in the postoperative situation. Postoperative care included regular MRI scans. Local progression was defined as an enlargement of the maximum tumor diameter by 10% or a new tumor growth within the planning target volume (PTV). LC and OS were determined using the Kaplan-Meier method. Furthermore, the relevance of various prognostic factors for LC and OS was assessed by univariate and multivariate analysis.
Results
The median follow-up period was 60 months (range 1.3–97.4 months). The 5-year rates for LC, progression-free survival, metastasis-free survival and OS were 53, 53, 52 and 74%, respectively. Local recurrence was observed in 31 patients (46%), occurring after a median follow-up time of 25 months (range 2.5–73.1 months). Only 10% of local recurrences occurred later than 5 years after RT. Statistical analysis showed that RT in the relapse situation corresponded to inferior LC rates compared to the primary situation, while other factors such as the GTV, radiation dose (EQD2) and treatment approach (CIRT alone vs. CIRT combined with photons) were insignificant. For OS after RT, patient age and PTV size proved to be significant predictors.
The incidence of late toxicity ≥ III° according to CTCAE v5.0 was 21%. Sacral insufficiency fractures occurred in 49% of patients (maximum III°: 16%) and were thus by far the most frequent late side effect in our analysis. Radiogenic damage to the peripheral nerves, intestinal tract and skin was observed in only 9% (≥ III°: 5%), 3% (all II°) and 9% (all I°) of patients.
Conclusion
Our analysis showed only moderate long-term LC rates after carbon ion-based RT, with sacral chordomas having a particularly poor prognosis in the recurrent situation. Therefore, future studies should evaluate the safety and effectiveness of further dose escalation and hypofractionation of RT in sacral chordoma and weight potential benefits of dose escalation against side effects.
Journal Article
Sacral insufficiency fractures after high-dose carbon-ion based radiotherapy of sacral chordomas
by
Sprave, Tanja
,
Welzel, Thomas
,
Akbaba, Sati
in
Adaptor Proteins, Signal Transducing
,
Adult
,
Aged
2018
Background
This study aimed to analyse the frequency and clinical relevance of sacral insufficiency fractures (SIFs) after high-dose carbon-ion based irradiation of sacral chordomas.
Methods
A total of 56 patients were included in this retrospective study. Twenty one patients (37%) were treated with definitive radiotherapy (RT), and 35 patients (63%) received postoperative RT using carbon ions, either in combination with photons or as single-modality treatment (median radiation dose 66 Gy RBE, range 60–74 Gy). Follow-up examinations including MRI of the pelvis were performed at 3-monthly intervals in the first year and consecutively at 6-monthly intervals. Median follow-up was 35.5 months (range 2–83).
Results
SIFs were diagnosed in 29 patients (52%) after a median follow-up of 11 months (range 1–62 months). Most sacral fractures (79%) occurred within 2 years after RT. For the overall study population, the fracture-free survival probability amounted to values of 0.68 (95% CI, 0.53–0.79) after 1 year, 0.46 (95% CI, 0.31–0.60) after 2 years, and 0.31 (95% CI, 0.16–0.47) after 5 years. Statistical analysis showed no significant difference regarding the fracture rates between patients who received an operation and postoperative RT and patients treated with definitive RT. About one third of the patients with SIFs (34%; 10 of 29 patients) had associated clinical symptoms, most notably pain. All patients with symptomatic fractures required strong analgesics and often intensive pain management.
Conclusions
Sacral fractures after high-dose carbon ion-based RT of sacral chordomas were shown to be a considerable radiogenic late effect, affecting about half of the treated patients. However, only one third of these fractures were clinically symptomatic requiring regular medical care and pain therapy.
Further hazard factor analysis in the future with larger patient numbers will possibly enable the identification of high-risk patients for developing SIFs with the ultimate goal to prevent symptomatic fractures.
Journal Article
Resistance training concomitant to radiotherapy of spinal bone metastases – survival and prognostic factors of a randomized trial
by
Schlampp, Ingmar
,
Welzel, Thomas
,
Debus, Jürgen
in
Biomedical and Life Sciences
,
Biomedicine
,
Brachytherapy
2016
Purpose
To compare the effects of resistance training versus passive physical therapy on bone survival in the metastatic bone during radiation therapy (RT) as combined treatment in patients with spinal bone metastases. Secondly, to evaluate overall survival and progression-free-survival (PFS) as well as to quantify prognostic factors of bone survival after combined treatment.
Methods
In this randomized trial 60 patients were allocated from September 2011 until March 2013 into one of the two groups: resistance training (group A) or passive physical therapy (group B) with thirty patients in each group during RT. We estimated patient survival using Kaplan-Meier survival method. The Wald-test was used to evaluate the prognostic importance of pathological fracture, primary site, Karnofsky performance status, localization of metastases, number of metastases, and cerebral metastases.
Results
Median follow-up was 10 months (range 2–35). Bone survival showed no significant difference between groups (
p
= .303). Additionally no difference between groups could be detected in overall survival (
p
= .688) and PFS (
p
= .295). Local bone progression was detected in 16.7 % in group B, no irradiated bone in group A showed a local progression over the course (
p
= 0.019). In univariate analysis breast cancer, prostate cancer, and the presence of cerebral metastases had a significant impact on bone survival in group B, while no impact could be demonstrated in group A.
Conclusions
In this group of patients with spinal bone metastases we were able to show that guided resistance training of the paravertebral muscles had no essential impact on survival concomitant to RT. Importantly, no local bone progression in group A was detected, nevertheless no prognostic factor for combined treatment could be evaluated.
Trial registration
Clinical trial identifier
NCT 01409720
. Registered 8 February 2011.
Journal Article
Biologically consistent dose accumulation using daily patient imaging
2021
Background
This work addresses a basic inconsistency in the way dose is accumulated in radiotherapy when predicting the biological effect based on the linear quadratic model (LQM). To overcome this inconsistency, we introduce and evaluate the concept of the total biological dose, bEQD
d
.
Methods
Daily computed tomography imaging of nine patients treated for prostate carcinoma with intensity-modulated radiotherapy was used to compute the delivered deformed dose on the basis of deformable image registration (DIR). We compared conventional dose accumulation (DA) with the newly introduced bEQD
d
, a new method of accumulating biological dose that considers each fraction dose and tissue radiobiology. We investigated the impact of the applied fractionation scheme (conventional/hypofractionated), uncertainties induced by the DIR and by the assigned α/β-value.
Results
bEQD
d
was systematically higher than the conventionally accumulated dose with difference hot spots of 3.3–4.9 Gy detected in six out of nine patients in regions of high dose gradient in the bladder and rectum. For hypofractionation, differences are up to 8.4 Gy. The difference amplitude was found to be in a similar range to worst-case uncertainties induced by DIR and was higher than that induced by α/β.
Conclusion
Using bEQD
d
for dose accumulation overcomes a potential systematic inaccuracy in biological effect prediction based on accumulated dose. Highest impact is found for serial-type late responding organs at risk in dose gradient regions and for hypofractionation. Although hot spot differences are in the order of several Gray, in dose-volume parameters there is little difference compared with using conventional or biological DA. However, when local dose information is used, e.g. dose surface maps, difference hot spots can potentially change outcomes of dose-response modelling and adaptive treatment strategies.
Journal Article
Bone density and pain response following intensity-modulated radiotherapy versus three-dimensional conformal radiotherapy for vertebral metastases - secondary results of a randomized trial
by
Sprave, Tanja
,
Verma, Vivek
,
Schlampp, Ingmar
in
Aged
,
Biocompatibility
,
Biomedical and Life Sciences
2018
Background
This was a prespecified secondary analysis of a randomized trial that analyzed bone density and pain response following fractionated intensity-modulated radiotherapy (IMRT) versus three-dimensional conformal radiotherapy (3DCRT) for palliative management of spinal metastases.
Methods/materials
Sixty patients were enrolled in the single-institutional randomized exploratory trial, randomly assigned to receive IMRT or 3DCRT (30 Gy in 10 fractions). Along with pain response (measured by the Visual Analog Scale (VAS) and Chow criteria), quantitative bone density was evaluated at baseline, 3, and 6 months in both irradiated and unirradiated spinal bodies, along with rates of pathologic fractures and vertebral compression fractures.
Results
Relative to baseline, bone density increased at 3 and 6 months following IMRT by a median of 24.8% and 33.8%, respectively (
p
< 0.01 and
p
= 0.048). These figures in the 3DCRT cohort were 18.5% and 48.4%, respectively (p < 0.01 for both). There were no statistical differences in bone density between IMRT and 3DCRT at 3 (
p
= 0.723) or 6 months (
p
= 0.341). Subgroup analysis of osteolytic and osteoblastic metastases showed no differences between groups; however, mixed metastases showed an increase in bone density over baseline in the IMRT (but not 3DCRT) arm. The 3-month rate of the pathological fractures was 15.0% in the IMRT arm vs. 10.5% in the 3DCRT arm. There were no differences in pathological fractures at 3 (
p
= 0.676) and 6 (
p
= 1.000) months. The IMRT arm showed improved VAS scores at 3 (
p
= 0.037) but not 6 months (
p
= 0.430). Using Chow criteria, pain response was similar at both 3 (
p
= 0.395) and 6 (
p
= 0.732) months.
Conclusions
This the first prospective investigation evaluating the impact of IMRT vs. 3DCRT on bone density. Along with pain response and pathologic fracture rates, significant rises in bone density after 3 and 6 months were similar in both cohorts. Future randomized investigations with larger sample sizes are recommended.
Trial registration
NCT,
NCT02832830
. Registered 14 July 2016
Journal Article