Background: Whole-ventricular radiotherapy (WV-RT) followed by a boost to the tumor bed (WV-RT/TB) is recommended for intracranial germ cell tumors (IGCT). As the critical brain areas are mainly in the target volume vicinity, it is unclear if protons indeed substantially spare neurofunctional organs at risk (NOAR). Therefore, a dosimetric comparison study of WV-RT/TB was conducted to assess whether proton or photon radiotherapy achieves better NOAR sparing. Methods: Eleven children with GCT received 24 Gy(RBE) WV-RT and a boost up to 40 Gy(RBE) in 25 fractions of 1.6 Gy(RBE) with pencil beam scanning proton therapy (PBS-PT). Intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans were generated for these patients. NOAR were delineated and treatment plans were compared for target volume coverage (TVC), homogeneity index (HI), inhomogeneity coefficient (IC) and (N)OAR sparing. Results: TVC was comparable for all three modalities. Compared to IMRT and VMAT, PBS-PT showed statistically significant optimized IC, as well as dose reduction, among others, in mean and integral dose to the: normal brain (-35.2%,-32.7%; À35.2%,-33.0%, respectively), cerebellum (-53.7%,-33.1%;-53.6%,-32.7%) and right temporal lobe (-14.5%, À31.9%; À14.7%, À29.9%). The Willis' circle was better protected with PBS-PT than IMRT (À7.1%; À7.8%). The left hippocampus sparing was higher with IMRT. Compared to VMAT, the dose to the hippocampi, amygdalae and temporal lobes was significantly decreased in the IMRT plans. Conclusions: Dosimetric comparison of WV-RT/TB in IGCT suggests PBS-PT's advantage over photons in conformality and NOAR sparing, whereas IMRT's superiority over VMAT, thus potentially minimizing long-term sequelae.
Background
The use of stereotactic body radiation therapy (SBRT) for tumor and pain control in patients with bone metastases is increasing. We report response assessment after bone SBRT using radiological changes through time and clinical examination of patients.
Methods
We analyzed retrospectively oligo-metastatic/progressive patients with bony lesions treated with SBRT between 12/2008 and 10/2018, without in-field re-irradiation, in our institution. Radiological data were obtained from imaging modalities used for SBRT planning and follow-up purposes in picture archiving and communication system and assessed by two independent radiologists blind to the time of treatment. Several radiological changes were described. Radiographic response assessment was classified according to University of Texas MD Anderson Cancer Center criteria. Pain response and the neurological deficit were captured before and at least 6 months after SBRT.
Results
A total of 35 of the 74 reviewed patients were eligible, presenting 43 bone metastases, with 51.2% (n = 22) located in the vertebral column. Median age at the time of SBRT was 66 years (range 38–84) and 77.1% (n = 27) were male. Histology was mainly prostate (51.4%, n = 18) and breast cancer (14.3%, n = 5). Median total radiation dose delivered was 24 Gy (range 24–42), in three fractions (range 2–7), prescribed to 70–90% isodose-line. After a median follow-up of 1.8 years (range < 1–8.2) for survivors, complete or partial response, stable, and progressive disease occurred in 0%, 11.4% (n = 4), 68.6% (n = 24), and 20.0% (n = 7) of the patients, respectively. Twenty patients (57.1%) died during the follow-up time, all from disease progression, yet 70% (n = 14) from this population with local stable disease after SBRT. From patients who were symptomatic and available for follow-up, almost half (44.4%) reported pain reduction after SBRT.
Conclusions
Eighty percent of the patients showed local control after SBRT for bone metastases. Pain response was favorable. For more accurate response assessment, comparing current imaging modalities with advanced imaging techniques such as functional MRI and PET/CT, in a prospective and standardized way is warranted.
Trial registration Retrospectively registered.
These preliminary data suggest that the outcomes of children and AYA with EWS are good and PT was well tolerated with few late adverse events. The local and distant tumor control for older patients with large pre-PT tumor volumes remains problematic.
Re-irradiation is one of the treatment options for recurrent lung cancer after initial (chemo-) radiotherapy. However, the safety and efficacy of definitive re-irradiation for recurrent lung cancer was not completely understood. We investigated the outcomes of definitive reirradiation in our clinic for recurrent lung cancer patients who received primary chemo-radiotherapy in locally advanced stage. Materials/Methods: We collected data from 36 lung cancer patients received definitive re-irradiation by using IMRT for local recurrence after (chemo-)radiotherapy. The median age was 68 (range, 45e88) years. Histology findings showed adenocarcinoma in 11 patients (30.6%), squamous cell carcinoma in 14 patients (38.9%) and small cell carcinoma in 11 patients (30.6%). The recurrences were found in primary site in 22 patients (61.1%), and lymph node in 13 patients (36.1%) and both primary and lymph node in 1 patient (2.8%). The period from the initial radiotherapy to reirradiation was 23.4 (range, 8.5e102.6) months. The median of initial radiation, re-irradiation and total dose was 72 Gy, 86.8 Gy and 154.3 Gy (BED10), respectively. Late toxicities grade3 were evaluated according to the Common Terminology Criteria for Adverse Events ver. 3.0. The local control and overall survival were analyzed with the KaplaneMeier method. Results: The median follow-up was 14.6 months. The 1-year local control and overall survival was 74.1% and 78.7%, respectively. On univariate analysis, adenocarcinoma was a significant prognostic factor for local control (p<0.01). The 1-year local control was 100% in adenocarcinoma, 58.3% in squamous cell carcinoma and 75.0% in small cell carcinoma. Grade 5 late toxicities were occurred in 2 patients (5.6%) including esophageal perforation and bronchial perforation. No other grade3 late toxicities were occurred. Conclusion: Definitive re-irradiation for recurrent locally advanced lung cancer was effective and feasible. Lung adenocarcinoma patients might be a good indication for re-irradiation.
Background The use of stereotactic body radiation therapy (SBRT) for tumor- and pain control in patients with bone metastases is increasing. Here, we report response assessment after bone SBRT using radiological changes through time and clinical examination of patients. MethodsWe analyzed retrospectively the oligo-metastatic/progressive patients with bony lesions treated with SBRT between 12/2008 and 10/2018 in our institution. Radiological data were obtained from imaging modalities used for SBRT planning and follow-up (FU) purposes in PACS and assessed by two independent radiologists blind to the time of treatment. Several radiological changes were described. Radiographic response assessment was classified according to University of Texas MD Anderson Cancer Center criteria. Pain response was captured pre- and >= 6 months post-SBRT.ResultsA total of 35 of the 74 reviewed patients were eligible, presenting 43 bone metastases, with 51.2% (n=22) located in vertebral column. Median age at the time of SBRT was 66 years (range, 38-84), and 77.1% (n=27) were male. Histology was mainly prostate (51.4%, n=18) and breast cancer (14.3%, n=5). Median total radiation dose delivered was 24 Gy (range: 24-42), in three fractions (range: 2-7), prescribed to 70 - 90% isodose-line. After a median FU of 1.8 years (range, 0.1-8.2) for survivors, complete-/ partial response, stable (SD), and progressive disease occurred in 0%, 11.4% (n=4), 68.6% (n=24) and 20.0% (n=7) of the patients respectively. Twenty patients (57.1%) died during the FU time, all from disease progression, yet 70% (n=14) from this population with local SD after SBRT. From patients who were symptomatic and available for FU, almost 50% reported pain reduction after SBRT.ConclusionsEighty percent of the patients showed local control (LC) after SBRT for bone metastases. Pain response was favorable. For more accurate response assessment, comparing current imaging modalities with advanced imaging techniques such as functional MRI and PET-CT is warranted.Trial registrationRetrospectively registered.
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