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Local radiotherapeutic management of ependymomas with fractionated stereotactic radiotherapy (FSRT)
Stephanie E Combs, Christoph Thilmann, Jürgen Debus, Daniela Schulz-Ertner
BMC Cancer , 2006, DOI: 10.1186/1471-2407-6-222
Abstract: From January 1992 to July 2003, FSRT was performed in 19 patients with histologically confirmed ependymomas. The median age was 15 years, 5 patients were younger than 4 years of age.Twelve patients received FSRT as primary postoperative radiotherapy after surgical resection. In 6 patients irradiation of the posterior fossa was performed with a local boost to the tumor bed, and in 4 patients the tumor bed only was irradiated. In 7 patients FSRT was performed as re-irradiation for tumor progression. This patient group was analyzed separately. A median dose of 54 Gy was prescribed in a median fractionation of 5 × 1.8 Gy per week for primary RT using 6 MeV photons with a linear accelerator. For FSRT as re-irradiation, a median dose of 36 Gy was applied. All recurrent tumors were localized within the former RT-field.The 5- and 10-year overall survival rates were 77% and 64%, respectively. Patients treated with FSRT for primary irradiation showed an overall survival of 100% and 78% at 3 and 5 years after irradiation of the posterior fossa with a boost to the tumor bed, and a survival rate of 100% at 5 years with RT of the tumor bed only. After re-irradiation with FSRT, survival rates of 83% and 50% at 3-and 5 years, respectively, were obtained.Progression-free survival rates after primary RT as compared to re-irradiation were 64% and 60% at 5 years, respectively.FSRT was well tolerated by all patients and could be completed without interruptions due to side effects. No severe treatment related toxicity > CTC grade 2 for patients treated with FSRT could be observed.The present analysis shows that FSRT is well tolerated and highly effective in the management of ependymal tumors. The rate of recurrences, especially at the field border, is not increased as compared to conventional radiotherapy consisting of craniospinal irradiation and a local boost to the posterior fossa.Ependymomas (EP) originate from ependymal cells of the wall of the cerebral ventricles, the central canal
Conventionally-fractionated image-guided intensity modulated radiotherapy (IG-IMRT): a safe and effective treatment for cancer spinal metastasis
Youling Gong, Jin Wang, Sen Bai, Xiaoqin Jiang, Feng Xu
Radiation Oncology , 2008, DOI: 10.1186/1748-717x-3-11
Abstract: 10 metastatic lesions were treated with conventionally-fractionated IG-IMRT. Daily kilovoltage cone-beam computed tomography (kV-CBCT) scan was applied to ensure accurate positioning. Plans were evaluated by the dose-volume histogram (DVH) analysis.Before set-up correction, the positioning errors in the left-right (LR), superior-inferior (SI) and anterior-posterior (AP) axes were 0.3 ± 3.2, 0.4 ± 4.5 and -0.2 ± 3.9 mm, respectively. After repositioning, those errors were 0.1 ± 0.7, 0 ± 0.8 and 0 ± 0.7 mm, respectively. The systematic/random uncertainties ranged 1.4–2.3/3.0–4.1 before and 0.1–0.2/0.7–0.8 mm after online set-up correction. In the original IMRT plans, the average dose of the planning target volume (PTV) was 61.9 Gy, with the spinal cord dose less than 49 Gy. Compared to the simulated PTVs based on the pre-correction CBCT, the average volume reduction of PTVs was 42.3% after online correction. Also, organ at risk (OAR) all benefited from CBCT-based set-up correction and had significant dose reduction with IGRT technique. Clinically, most patients had prompt pain relief within one month of treatment. There was no radiation-induced toxicity detected clinically during a median follow-up of 15.6 months.IG-IMRT provides a new approach to treat cancer spinal metastasis. The precise positioning ensures the implementation of optimal IMRT plan, satisfying both the dose escalation of tumor targets and the radiation tolerance of spinal cord. It might benefit the cancer patient with spinal metastasis.Spine is the most common place of cancer metastasis, especially for lung cancer and breast cancer. Each year, approximately 50,000 patients with cancer develop spinal metastasis worldwide and the 5-year over-all survival rate of these patients was less than 5% [1,2]. All together, accompanying with the improvement of therapy for malignant tumors, the overall survival time of cancer patients prolonged and the incidence of spinal metastasis was increasing gradually. Radi
Fractionated stereotactic radiotherapy for skull base tumors: analysis of treatment accuracy using a stereotactic mask fixation system
Giuseppe Minniti, Maurizio Valeriani, Enrico Clarke, Marco D'Arienzo, Michelangelo Ciotti, Roberto Montagnoli, Francesca Saporetti, Riccardo Enrici
Radiation Oncology , 2010, DOI: 10.1186/1748-717x-5-1
Abstract: Sixteen patients treated with FSRT were involved in the study. A commercial stereotactic mask fixation system (BrainLAB AG) was used for patient immobilization. Serial CT scans obtained before and during FSRT were used to assess the accuracy of patient immobilization by comparing the isocenter position. Daily portal imaging were acquired to establish day to day patient position variation. Displacement errors along the different directions were calculated as combination of systematic and random errors.The mean isocenter displacements based on localization and verification CT imaging were 0.1 mm (SD 0.3 mm) in the lateral direction, 0.1 mm (SD 0.4 mm) in the anteroposterior, and 0.3 mm (SD 0.4 mm) in craniocaudal direction. The mean 3D displacement was 0.5 mm (SD 0.4 mm), being maximum 1.4 mm. No significant differences were found during the treatment (P = 0.4). The overall isocenter displacement as calculated by 456 anterior and lateral portal images were 0.3 mm (SD 0.9 mm) in the mediolateral direction, -0.2 mm (SD 1 mm) in the anteroposterior direction, and 0.2 mm (SD 1.1 mm) in the craniocaudal direction. The largest displacement of 2.7 mm was seen in the cranio-caudal direction, with 95% of displacements < 2 mm in any direction.The results indicate that the setup error of the presented mask system evaluated by CT verification scans and portal imaging are minimal. Reproducibility of the isocenter position is in the best range of positioning reproducibility reported for other stereotactic systems.Stereotactic radiation techniques in form of radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT) are frequently employed in patients with skull base tumors in order to increase the precision of radiotherapy and decrease the potential long-term toxicity of treatment [1-3].FSRT using a commercially available stereotactic mask fixation system (BrainLAB AG) has been routinely used at University Hospital Sant'Andrea in patients with skull base tumors since 2006.
Radiotherapy and radiosurgery for benign skull base meningiomas
Giuseppe Minniti, Maurizio Amichetti, Riccardo Enrici
Radiation Oncology , 2009, DOI: 10.1186/1748-717x-4-42
Abstract: Surgical excision is the treatment of choice for accessible intracranial meningiomas. Following apparently complete removal of benign meningiomas the reported control rates are in the region of 95% at 5 years, 90% at 10 years and 70% at 15 years [1-10]. However, meningiomas located in the region of the base of skull are often difficult to access and only subtotal or partial resection is possible, with a high tendency for tumor regrowth.Local control following incomplete excision of a benign meningioma can be improved with conventional fractionated external beam radiotherapy (RT) with a reported 10-year progression-free survival in the region of 75-90% [11-13].Advances in radiation oncology include intensity-modulated radiotherapy (IMRT), fractionated stereotactic radiotherapy (FSRT) and stereotactic radiosurgery (SRS) that allow for more localised and precise irradiation. Recent studies using these new techniques report apparently high local control rates and low morbidity for skull base benign tumors as pituitary adenomas, craniopharyngiomas and meningiomas [14-18]. We performed a review of the published literature of fractionated RT and SRS for skull base meningiomas in an attempt to define reasonably objective and comparative information on the safety and efficacy of the individual techniques.Post-operative conventional RT has been reported effective both following subtotal surgical resection of benign meningiomas and at the time of recurrence. Using a dose of 50-55 Gy in 30-33 fractions the 10-year and 20-year local control rates are 70-80% (Table 1) [11-13,19-30].In a series of 82 patients with skull base meningiomas treated at the Royal Marsden Hospital between 1962 and 1992 using a dose of 55-60 Gy in 30-33 fractions, the 5-year and 10-year local tumor control rates were 92% and 83%, respectively [12]. Tumor site was the only significant predictor of local control, with a 10-year progression-free survival rate of 69% for patients with sphenoid ridge meningiom
Intensity modulated radiotherapy (IMRT) in the treatment of children and Adolescents - a single institution's experience and a review of the literature
Florian Sterzing, Eva M Stoiber, Simeon Nill, Harald Bauer, Peter Huber, Jürgen Debus, Marc W Münter
Radiation Oncology , 2009, DOI: 10.1186/1748-717x-4-37
Abstract: Between 1999 and 2008 thirty-one children and adolescents with a mean age of 14.2 years (1.5 - 20.5) were treated with IMRT in our department. This heterogeneous group of patients consisted of 20 different tumor entities, with Ewing's sarcoma being the largest (5 patients), followed by juvenile nasopharyngeal fibroma, esthesioneuroblastoma and rhabdomyosarcoma (3 patients each). In addition a review of the available literature reporting on technology, quality, toxicity, outcome and concerns of IMRT was performed.With IMRT individualized dose distributions and excellent sparing of organs at risk were obtained in the most challenging cases. This was achieved at the cost of an increased volume of normal tissue receiving low radiation doses. Local control was achieved in 21 patients. 5 patients died due to progressive distant metastases. No severe acute or chronic toxicity was observed.IMRT in the treatment of children and adolescents is feasible and was applied safely within the last 9 years at our institution. Several reports in literature show the excellent possibilities of IMRT in selective sparing of organs at risk and achieving local control. In selected cases the quality of IMRT plans increases the therapeutic ratio and outweighs the risk of potentially increased rates of secondary malignancies by the augmented low dose exposure.In more than a decade of clinical Intensity Modulated Radiation Therapy (IMRT) this method of high precision radiotherapy has proven remarkable advances in target conformity, dose escalation in the target volume and sparing of neighbouring organs at risk [1-14]. These qualities permit the irradiation of patients with complex shaped tumors at problematic locations which could not be treated successfully with conventional radiation methods. Within IMRT again different technical solutions are being used. They all have the principle in common that radiation beams with different intensities are used depending on how much tumor or organ at risk
Fractionated stereotactic radiotherapy for treatment of locally recurrent nasopharyngeal carcinoma

TANG Jian-min
, HOU Yan-li, DAI Li-yan, et al

- , 2015, DOI: 11.3969/j.issn.1674-8115.2015.01.018
Abstract: 目的 评价采用伽玛射线立体定向放射治疗系统行分次立体定向放射治疗(FSRT)对放射治疗后复发鼻咽癌的疗效和不良反应。 方法 应用FSRT对30例鼻咽癌患者分2组进行治疗,应用50%等剂量曲线,分次剂量均为2 Gy,每周连续治疗5次。其中复发推量组8例,中位处方剂量为15 Gy;单纯复发治疗组22例,中位处方剂量为40 Gy。 结果 FSRT治疗后3个月,复发推量组患者完全缓解(CR)和部分缓解(PR)分别为87.5%(7/8)和12.5%(1/8),单纯复发治疗组CR和PR分别为77.3%(17/22)和22.7%(5/22)。全组病例随访时间10~70个月,中位随访时间为26个月。全组生存患者卡氏评分≥90者为95.2%(20/21)。复发推量组患者1年生存率和局部控制率分别为77.78%和77.78%,2年生存率和局部控制率分别为51.85%和77.78%;单纯复发治疗组患者1年生存率和局部控制率分别为90.23%和90.23%,2年生存率和局部控制率分别为82.71%和74.01%。 结论 FSRT对放疗后复发鼻咽癌有良好的局部控制效果,值得临床进一步探讨。
: Objective To evaluate the therapeutic effect and adverse reactions of fractionated stereotactic radiotherapy (FSRT) for the treatment of locally recurrent nasopharyngeal carcinoma after radiotherapy by the gamma ray stereotactic radiotherapy. Methods A total of 30 patients with recurrent nasopharyngeal carcinoma were divided into two groups (A group and B group) and treated by FSRT. The prescription dose at 50% isodose line was 2 Gy each time and each patient consecutively underwent 5 treatments per week. The mean doses of A group (n=8) and B group (n=22) were 15 Gy and 40 Gy, respectively. Results The complete response (CR) and partial response (PR) rates of A group were 87.5% (7/8) and 12.5% (1/8) after being treated by FSRT for 3 months and the CR and PR rates of B group were 77.3% (17/22) and 22.7% (5/22). The follow-up time was 10-70 months and the median follow-up time was 26 months. The Karnofsky performance status scores for 95.2%(20/21) of the surviving patients were over 90. The one-year survival rate and local control rate of A group were 77.78% and 77.78% and two-year survival rate and local control rate were 51.85% and 77.78%. The one year survival rate and local control rate of B group were 90.23% and 90.23% and two-year survival rate and local control rate were 82.71% and 74.01%. Conclusion The local control effect of FSRT on locally recurrent nasopharyngeal carcinoma after radiotherapy is good and it is worth further clinical studies
Advances of Precise Radiotherapy for Lung Cancer  [cached]
Xin WANG,Feng XU,Yuquan WEI
Chinese Journal of Lung Cancer , 2011, DOI: 10.3779/j.issn.1009-3419.2011.11.12
Abstract: At present lung tumor radiation therapy has entered the accurate radiotherapy era. Precise radiotherapy includes intensity modulated radiotherapy (IMRT), image-guided radiotherapy (IGRT) and stereotactic body radiotherapy (SBRT). During the process of implementing precise radiotherapy, these problems should be fully considered to ensure executing precise radiotherapy accurately: patient positioning, controlling of the lung tumor motion, selecting of image techniques, PTV margin, dose prescription and reporting, arrangement of beams, controlling of dose volume and treatment delivering.
Primary Meningeal Rhabdomyosarcoma  [PDF]
Manisha Palta,Richard F. Riedel,James J. Vredenburgh,Thomas J. Cummings,Scott Green,Zheng Chang,John P. Kirkpatrick
Sarcoma , 2011, DOI: 10.1155/2011/312802
Abstract: Primary meningeal rhabdomyosarcoma is a rare primary brain malignancy, with scant case reports. While most reports of primary intracranial rhabdomyosarcoma occur in pediatric patients, a handful of cases in adult patients have been reported in the medical literature. We report the case of a 44-year-old male who developed primary meningeal rhabdomyosarcoma. After developing episodes of right lower extremity weakness, word finding difficulty, and headaches, a brain magnetic resonance imaging (MRI) demonstrated a vertex lesion with radiographic appearance of a meningeal-derived tumor. Subtotal surgical resection was performed due to sagittal sinus invasion and initial pathology was interpreted as an anaplastic meningioma. Re-review of pathology demonstrated rhabdomyosarcoma negative for alveolar translocation t(2;13). Staging studies revealed no evidence of disseminated disease. He was treated with stereotactic radiotherapy with concurrent temozolamide to be followed by vincristine, actinomycin-D, and cyclophosphamide (VAC) systemic therapy.
Inverse planned stereotactic intensity modulated radiotherapy (IMRT) in the treatment of incompletely and completely resected adenoid cystic carcinomas of the head and neck: initial clinical results and toxicity of treatment
MW Münter, D Schulz-Ertner, H Hof, A Nikoghosyan, A Jensen, S Nill, P Huber, J Debus
Radiation Oncology , 2006, DOI: 10.1186/1748-717x-1-17
Abstract: 25 patients with huge ACC in different areas of the head and neck were treated. At the time of radiotherapy two patients already suffered from distant metastases. A complete resection of the tumor was possible in only 4 patients. The remaining patients were incompletely resected (R2: 20; R1: 1). 21 patients received an integrated boost IMRT (IBRT), which allow the use of different single doses for different target volumes in one fraction. All patients were treated after inverse treatment planning and stereotactic target point localization.The mean folllow-up was 22.8 months (91 – 1490 days). According to Kaplan Meier the three year overall survival rate was 72%. 4 patients died caused by a systemic progression of the disease. The three-year recurrence free survival was according to Kaplan Meier in this group of patients 38%. 3 patients developed an in-field recurrence and 3 patient showed a metastasis in an adjacent lymph node of the head and neck region. One patient with an in-field recurrence and a patient with the lymph node recurrence could be re-treated by radiotherapy. Both patients are now controlled. Acute side effects >Grade II did only appear so far in a small number of patients.The inverse planned stereotactic IMRT is feasible in the treatment of ACC. By using IMRT, high control rates and low side effects could by achieved. Further evaluation concerning the long term follow-up is needed. Due to the technical advantage of IMRT this treatment modality should be used if a particle therapy is not available.Adenoid cystic carcinomas of the head and neck are a unique kind of tumour deriving from cells of the major and minor salivary glands, they account for 25% of all malignant salivary gland tumours in different series. Although ACCs are the most common histological type of tumours in the minor salivary glands with a total of 55% [1] they account for only about 10–15% of all parotid gland malignancies. ACCs can be shown to be unique for various reasons: first
Intensity Modulated Radiotherapy (IMRT) in the Planning of Hypofractionated Treatment in Head and Neck Tumors  [PDF]
Misleidy Nápoles Morales, Rogelio Díaz Moreno
International Journal of Clinical Medicine (IJCM) , 2018, DOI: 10.4236/ijcm.2018.99056
Abstract: Head and neck cancer (HNCC) is the sixth most common cancer with an incidence of approximately 600,000 cases per year and 300,000 annual deaths worldwide1y2. In Cuba, cancer of the larynx is the fourth cause in incidence, being the fourth cause of cancer death in men. Radiotherapy constitutes an important modality in the control of these tumors and the Intensity Modulated Radiotherapy (IMRT) is a new advance in this field. With it, it is possible to improve dose distribution, decreasing the dose in adjacent healthy tissues and escalating dose in tumor. In this work we present 33 patients of National Institute of Oncology and Radiobiology in Cuba (INOR), in whom the IMRT was used as a treatment technique with a hypofractionation of the dose. Their response was observed at the end of the treatment and one month later. 56% (19) of the patients had a complete response to treatment at the primary site of the tumor and neck. 10% (3) had no response, progressed. 11 of the patients had no response at the lymph node site at the end of treatment, 8 of these 11 had complete remission one month after radiotherapy ended.
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