Christina Leitzen

Intensity-modulated radiotherapy of the prostate: Dynamic ADC monitoring by DWI at 3.0 T

BACKGROUND AND PURPOSE Diffusion weighted imaging (DWI) as a functional MR technique allows for both qualitative and quantitative assessment of tumour cellularity and changes during therapy. The objective of this study was to evaluate changes of apparent diffusion coefficient (ADC) in biopsy proven prostate cancer (PCa) under intensity modulated radiotherapy (IMRT) at 3T. MATERIAL & METHODS Thirteen patients with biopsy proven PCa treated with intensity modulated external beam radiotherapy (IMRT) underwent four standardized MR examinations after approval of the local institutional review board. These included DWI at 3T on a strict time table: before, in between, directly after (between 1 and 4 days after the last radiation), as well as 3 months after IMRT. Quantitative analysis of two different ADCs, - the ADC(0,800) and the ADC(50,800), was performed dynamically over 4 time points in PCa, gluteal muscle and healthy prostate tissue. RESULTS In PCa, a significant increase of ADC(0,800)/ADC(50,800) values was measured under IMRT by about 16%/15% (P=0.00008/0.00017), 21%/21% (P=0.00006/0.00030), and 33%/34% (P=0.00004/0.00002) at the three time points compared to initial value. Healthy prostate tissue did not show any significant increase. CONCLUSION DWI is suitable as a biomarker for radiation therapy response of PCa by allowing the dynamic monitoring of treatment effectiveness.

Prediction of Clinical Course of Glioblastomas by MRI during Radiotherapy

ZusammenfassungZiel:Trotz verbesserter therapeutischer Möglichkeiten ist der klinische Verlauf höhergradiger Gliome bislang unbefriedigend. Eine möglichst frühzeitige Abschätzung der Prognose könnte helfen, individuelle Therapieansätze zu finden. Ziel war es, zu eruieren, ob dies mithilfe von MRT-Verlaufskontrollen unter Strahlentherapie möglich ist.Patienten und Methodik:33 radiotherapeutisch behandelte Glioblastom-Patienten erhielten MRT-Verlaufskontrollen: vor Radiotherapiebeginn, nach ca. der Hälfte der Dosis (30 Gy), bei Radiotherapieabschluss (60 Gy) und in der Nachsorge. Die MRTUntersuchungsbefunde bei 30 und 60 Gy (drei Kategorien: Status idem, fraglicher Progress, Progress) wurden mit dem klinischen Verlauf über einen medianen Zeitraum von 11 Monaten korreliert.Ergebnisse:Nach 30 Gy zeigten 23/33 (70%) einen Status idem im MRT. 10/33 (30%) zeigten einen sicheren (n = 6) oder fraglichen Progress (n = 4). Diese Tumoren waren schneller progredient (weiterer Progress: 1 vs. 8 Monate nach Radiotherapieabschluss) und die Patienten verstarben früher (9 vs. 22 Monate) als diejenigen mit Status idem. Nach 60 Gy zeigten 14/33 Fällen (42%) einen sicheren (n = 8) oder fraglichen (n = 6) Progress. Ebenso wie bei der Kontrolle bei 30 Gy waren diese Tumoren schneller weiter progredient (1 vs. 9 Monate nach Radiotherapieabschluss) und die Patienten verstarben früher (9 vs. 22 Monate) als diejenigen mit Status idem.Schlussfolgerung:Die MRT-Verlaufskontrolle nach 30 Gy erlaubt eine Abschätzung der weiteren Prognose. Ergeben sich Hinweise auf einen Progress, verkürzt sich das mediane Überleben auf 9 Monate. Auf dieser Grundlage kann zu diesem Zeitpunkt eine Anpassung der Therapie diskutiert werden.AbstractPurpose:Determine the value of MR studies in patients undergoing radiotherapy for glioblastomas pre and during radiotherapy to predict the clinical course.Patients and Methods:MR follow-up studies were performed in 33 patients with glioblastomas before radiotherapy, after 30 Gy, after 60 Gy, and in the treatment follow-up. Findings on MR were categorized into: definite progress, questionable progress, status idem. Patients were followed clinically (median for 11 months).Results:After 30 Gy 23/33 (70%) of the MR examination showed status idem. 10/33 (30%) demonstrated definite (n = 6) or questionable (n = 4) progress. Further tumor progress was faster in these patients and patients succumb to their disease earlier (9 vs. 22 months). The 60 Gy study showed definite (n = 8) and questionable (n = 6) progress in 14/33 (42%) cases. All these tumors were progressing faster and were associated with a comparatively reduced life expectancy.Conclusion:MR follow-up studies after 30 Gy in patients undergoing radiotherapy for glioblastomas allow for prognostic appraisal, and potentially early modification of treatment.PURPOSE determine the value of MR studies in patients undergoing radiotherapy for glioblastomas pre and during radiotherapy to predict the clinical course. PATIENTS AND METHODS MR follow-up studies were performed in 33 patients with glioblastomas before radiotherapy, after 30 Gy, after 60 Gy, and in the treatment follow-up. Findings on MR were categorized into: definite progress, questionable progress, status idem. Patients were followed clinically (median for 11 months). RESULTS after 30 Gy 23/33 (70%) of the MR examination showed status idem. 10/33 (30%) demonstrated definite (n = 6) or questionable (n = 4) progress. Further tumor progress was faster in these patients and patients succumb to their disease earlier (9 vs. 22 months). The 60 Gy study showed definite (n = 8) and questionable (n = 6) progress in 14/33 (42%) cases. All these tumors were progressing faster and were associated with a comparatively reduced life expectancy. CONCLUSION MR follow-up studies after 30 Gy in patients undergoing radiotherapy for glioblastomas allow for prognostic appraisal, and potentially early modification of treatment.

Extraretinal Induced Visual Sensations during IMRT of the Brain

BACKGROUND We observed visual sensations (VSs) in patients undergoing intensity modulated radiotherapy (IMRT) of the brain without the beam passing through ocular structures. We analyzed this phenomenon especially with regards to reproducibility, and origin. METHODS AND FINDINGS Analyzed were ten consecutive patients (aged 41-71 years) with glioblastoma multiforme who received pulsed IMRT (total dose 60Gy) with helical tomotherapy (TT). A megavolt-CT (MVCT) was performed daily before treatment. VSs were reported and recorded using a triggered event recorder. The frequency of VSs was calculated and VSs were correlated with beam direction and couch position. Subjective patient perception was plotted on an 8x8 visual field (VF) matrix. Distance to the orbital roof (OR) from the first beam causing a VS was calculated from the Dicom radiation therapy data and MVCT data. During 175 treatment sessions (average 17.5 per patient) 5959 VSs were recorded and analyzed. VSs occurred only during the treatment session not during the MVCTs. Plotting events over time revealed patient-specific patterns. The average cranio-caudad extension of VS-inducing area was 63.4mm (range 43.24-92.1mm). The maximum distance between the first VS and the OR was 56.1mm so that direct interaction with the retina is unlikely. Data on subjective visual perception showed that VSs occurred mainly in the upper right and left quadrants of the VF. Within the visual pathways the highest probability for origin of VSs was seen in the optic chiasm and the optic tract (22%). CONCLUSIONS There is clear evidence that interaction of photon irradiation with neuronal structures distant from the eye can lead to VSs.

Prognoseeinschätzung durch MR-Verlaufskontrollen während der Strahlentherapie bei Glioblastom-Patienten@@@Prediction of Clinical Course of Glioblastomas by MRI during Radiotherapy

ZusammenfassungZiel:Trotz verbesserter therapeutischer Möglichkeiten ist der klinische Verlauf höhergradiger Gliome bislang unbefriedigend. Eine möglichst frühzeitige Abschätzung der Prognose könnte helfen, individuelle Therapieansätze zu finden. Ziel war es, zu eruieren, ob dies mithilfe von MRT-Verlaufskontrollen unter Strahlentherapie möglich ist.Patienten und Methodik:33 radiotherapeutisch behandelte Glioblastom-Patienten erhielten MRT-Verlaufskontrollen: vor Radiotherapiebeginn, nach ca. der Hälfte der Dosis (30 Gy), bei Radiotherapieabschluss (60 Gy) und in der Nachsorge. Die MRTUntersuchungsbefunde bei 30 und 60 Gy (drei Kategorien: Status idem, fraglicher Progress, Progress) wurden mit dem klinischen Verlauf über einen medianen Zeitraum von 11 Monaten korreliert.Ergebnisse:Nach 30 Gy zeigten 23/33 (70%) einen Status idem im MRT. 10/33 (30%) zeigten einen sicheren (n = 6) oder fraglichen Progress (n = 4). Diese Tumoren waren schneller progredient (weiterer Progress: 1 vs. 8 Monate nach Radiotherapieabschluss) und die Patienten verstarben früher (9 vs. 22 Monate) als diejenigen mit Status idem. Nach 60 Gy zeigten 14/33 Fällen (42%) einen sicheren (n = 8) oder fraglichen (n = 6) Progress. Ebenso wie bei der Kontrolle bei 30 Gy waren diese Tumoren schneller weiter progredient (1 vs. 9 Monate nach Radiotherapieabschluss) und die Patienten verstarben früher (9 vs. 22 Monate) als diejenigen mit Status idem.Schlussfolgerung:Die MRT-Verlaufskontrolle nach 30 Gy erlaubt eine Abschätzung der weiteren Prognose. Ergeben sich Hinweise auf einen Progress, verkürzt sich das mediane Überleben auf 9 Monate. Auf dieser Grundlage kann zu diesem Zeitpunkt eine Anpassung der Therapie diskutiert werden.AbstractPurpose:Determine the value of MR studies in patients undergoing radiotherapy for glioblastomas pre and during radiotherapy to predict the clinical course.Patients and Methods:MR follow-up studies were performed in 33 patients with glioblastomas before radiotherapy, after 30 Gy, after 60 Gy, and in the treatment follow-up. Findings on MR were categorized into: definite progress, questionable progress, status idem. Patients were followed clinically (median for 11 months).Results:After 30 Gy 23/33 (70%) of the MR examination showed status idem. 10/33 (30%) demonstrated definite (n = 6) or questionable (n = 4) progress. Further tumor progress was faster in these patients and patients succumb to their disease earlier (9 vs. 22 months). The 60 Gy study showed definite (n = 8) and questionable (n = 6) progress in 14/33 (42%) cases. All these tumors were progressing faster and were associated with a comparatively reduced life expectancy.Conclusion:MR follow-up studies after 30 Gy in patients undergoing radiotherapy for glioblastomas allow for prognostic appraisal, and potentially early modification of treatment.PURPOSE determine the value of MR studies in patients undergoing radiotherapy for glioblastomas pre and during radiotherapy to predict the clinical course. PATIENTS AND METHODS MR follow-up studies were performed in 33 patients with glioblastomas before radiotherapy, after 30 Gy, after 60 Gy, and in the treatment follow-up. Findings on MR were categorized into: definite progress, questionable progress, status idem. Patients were followed clinically (median for 11 months). RESULTS after 30 Gy 23/33 (70%) of the MR examination showed status idem. 10/33 (30%) demonstrated definite (n = 6) or questionable (n = 4) progress. Further tumor progress was faster in these patients and patients succumb to their disease earlier (9 vs. 22 months). The 60 Gy study showed definite (n = 8) and questionable (n = 6) progress in 14/33 (42%) cases. All these tumors were progressing faster and were associated with a comparatively reduced life expectancy. CONCLUSION MR follow-up studies after 30 Gy in patients undergoing radiotherapy for glioblastomas allow for prognostic appraisal, and potentially early modification of treatment.