Pencil beam scanning proton therapy for pediatric intracranial ependymoma.

To assess the clinical outcome and late side effect profile of pencil beam scanning proton therapy (PT) delivered to children with intracranial ependymoma. Between July-2004 and March-2013, 50 patients with intracranial ependymoma (n = 46, grade 3) received involved-field PT at Paul Scherrer Institute (PSI). Median age at time of PT was 2.

Proton therapy for uveal melanoma in 43 juvenile patients: long-term results.

Purpose: To examine the metastatic and survival rates, eye retention probability, and the visual outcomes of juvenile patients after proton beam radiotherapy (PBRT) for uveal melanoma (UM).

Design: Retrospective case-factor matched control study.

Participants And Controls: Forty-three patients younger than 21 years treated with PBRT for UM were compared with 129 matched adult control patients.

Spot-scanning proton radiation therapy for pediatric chordoma and chondrosarcoma: clinical outcome of 26 patients treated at paul scherrer institute.

Purpose: To evaluate the clinical results of fractionated spot-scanning proton radiation therapy (PT) in 26 pediatric patients treated at Paul Scherrer Institute for chordoma (CH) or chondrosarcoma (CS) of the skull base or axial skeleton.

Methods And Materials: Between June 2000 and June 2010, 19 CH and 7 CS patients with tumors originating from the skull base (17) and the axial skeleton (9) were treated with PT. Mean age at the time of PT was 13.

Dose to the developing dentition during therapeutic irradiation: organ at risk determination and clinical implications.

Purpose: Irradiation of pediatric facial structures can cause severe impairment of permanent teeth later in life. We therefore focused on primary and permanent teeth as organs at risk, investigating the ability to identify individual teeth in children and infants and to correlate dose distributions with subsequent dental toxicity.

Methods And Materials: We retrospectively reviewed 14 pediatric patients who received a maximum dose >20 Gy(relative biological effectiveness, RBE) to 1 or more primary or permanent teeth between 2003 and 2009.

Temporal lobe toxicity analysis after proton radiation therapy for skull base tumors.

Purpose: Temporal lobe (TL) parenchyma toxicity constitutes one of the most frequent late adverse event in high-dose proton therapy (PT) for tumors of the skull base. We analyzed clinical events with dosimetric parameters in our patients treated for skull base tumors with spot-scanning PT.

Methods And Materials: Between 1998 and 2005, a total of 62 patients received PT to a median dose of 71.

Spot scanning-based proton therapy for intracranial meningioma: long-term results from the Paul Scherrer Institute.

Background: To assess the long-term clinical results of spot scanning proton therapy (PT) in the treatment of intracranial meningiomas.

Patients And Methods: Thirty-nine patients with meningioma (histologically proven 34/39) were treated with PT between July 1997 and January 2010. Thirty-two (82.

Spot-scanning-based proton therapy for extracranial chordoma.

Purpose: To evaluate effectiveness and safety of spot-scanning-based proton-radiotherapy (PT) for extracranial chordomas (ECC).

Methods And Material: Between 1999-2006, 40 patients with chordoma of C-, T-, and L-spine and sacrum were treated at Paul Scherrer Institute (PSI) with PT using spot-scanning. Median patient age was 58 years (range, 10-81 years); 63% were male, and 36% were female.

Postoperative proton radiotherapy for localized and locoregional breast cancer: potential for clinically relevant improvements?

Purpose: To study the potential reduction of dose to organs at risk (OARs) with intensity-modulated proton radiotherapy (IMPT) compared with intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3D-CRT) photon radiotherapy for left-sided breast cancer patients.

Methods And Materials: Comparative treatment-planning was performed using planning computed tomography scans of 20 left-sided breast cancer patients. For each patient, three increasingly complex locoregional volumes (planning target volumes [PTVs]) were defined: whole breast (WB) or chest wall (CW) = (PTV1), WB/CW plus medial-supraclavicular (MSC), lateral-supraclavicular (LSC), and level III axillary (AxIII) nodes = (PTV2) and WB/CW+MSC+LSC+AxIII plus internal mammary chain = (PTV3).

Proton spot scanning radiotherapy of spontaneous canine tumors.

Thirty dogs with spontaneous tumors were irradiated with proton therapy using a novel spot scanning technique to evaluate the safety and efficacy of the system, and to study the acute and late radiation reactions. Nasal tumors, soft tissue sarcomas, and miscellaneous tumors of the head were treated with a median total dose of 52.5 Gy given in 3.

Effectiveness and safety of spot scanning proton radiation therapy for chordomas and chondrosarcomas of the skull base: first long-term report.

Purpose: To evaluate effectiveness and safety of spot-scanning-based proton radiotherapy (PT) in skull-base chordomas and chondrosarcomas.

Methods And Materials: Between October 1998 and November 2005, 64 patients with skull-base chordomas (n = 42) and chondrosarcomas (n = 22) were treated at Paul Scherrer Institute with PT using spot-scanning technique. Median total dose for chordomas was 73.

Experiences at the Paul Scherrer Institute with a remote patient positioning procedure for high-throughput proton radiation therapy.

Purpose: To describe a remote positioning system for accurate and efficient proton radiotherapy treatments.

Methods And Materials: To minimize positioning time in the treatment room (and thereby maximize beam utility), we have adopted a method for remote patient positioning, with patients positioned and imaged outside the treatment room. Using a CT scanner, positioning is performed using orthogonal topograms with the measured differences to the reference images being used to define daily corrections to the patient table in the treatment room.

Adjuvant intra-arterial hepatic fotemustine for high-risk uveal melanoma patients.

Uveal melanoma metastases occur most commonly in the liver. Given the 50% mortality rate in patients at high risk of developing liver metastases, we tested an adjuvant intra-arterial hepatic (i.a.

New developments in external beam radiotherapy for retinoblastoma: from lens to normal tissue-sparing techniques.

Historically, retinoblastoma was treated with external beam radiotherapy (EBR) and for many years this was the accepted standard of care. With greater knowledge of radiation-induced morbidity and mortality, the trend over the past decade has shifted towards primary chemotherapy for most globe conservative treatments. Such a radical change in treatment modalities has restrained EBR to second-line and salvage indications with little consensus regarding dose, timing and techniques.

Sensitivity of intensity modulated proton therapy plans to changes in patient weight.

Purpose: A retrospective study to investigate the sensitivity of intensity modulated proton therapy (IMPT) to changes in body weight occurring during the course of radiotherapy for patients treated in the sacral region.

Materials And Methods: During therapy, important weight gain and loss were observed for two patients treated to para-spinal tumors, which resulted in both patients being re-scanned and re-planned. Both patients were treated as part of their therapy, with a narrow-angle IMPT (NA-IMPT) plan delivering a 'dose hole' around the cauda equina (CE), which was mainly formed through modulation of Bragg peaks in depth.

Postoperative spot-scanning proton radiation therapy for chordoma and chondrosarcoma in children and adolescents: initial experience at paul scherrer institute.

Purpose: To evaluate postoperative spot-scanning proton radiation therapy (PT) and intensity-modulated PT (IMPT) for chordoma and chondrosarcoma in pediatric patients.

Methods And Materials: Between 2000 and 2005, 10 patients (six male patients, four female patients; six chordomas, four chondrosarcomas), aged 10-20 years (median, 16 years), were treated at our institute. Tumor sites were in the brain (one case), skull base (five cases), cervical (three cases), and lumbar spine (one case).

Novel technique of craniospinal axis proton therapy with the spot-scanning system: avoidance of patching multiple fields and optimized ventral dose distribution.

Background And Purpose: Conventional craniospinal irradiation (CSI) is a complex procedure carrying a high risk of adverse side effects. Still, it is indispensable for cure in a number of pediatric brain tumors. In this study, the feasibility and the potential advantage of spot-scanning proton therapy for CSI are investigated.

Deep propofol sedation for vacuum-assisted bite-block immobilization in children undergoing proton radiation therapy of cranial tumors.

Background: Vacuum-assisted bite-block immobilization of the head is a reliable technique for reproducible precise head positioning as used for proton radiation in adults. We report preliminary experience using deep propofol sedation without an artificial airway in children undergoing proton radiation of cranial tumors requiring vacuum-assisted bite-block immobilization.

Methods: Sedation was started with a bolus of i.

Spot scanning proton therapy in the curative treatment of adult patients with sarcoma: the Paul Scherrer institute experience.

Purpose: To assess the safety and efficacy of spot scanning proton beam therapy (PT) in the curative treatment of soft-tissue sarcoma (STS) in adults patients.

Patients And Methods: We identified 13 STS patients treated with PT between July 1998 and May 2005 in our institutional database. Tumor histology varied with the most common histologic subtypes including liposarcoma and peripheral nerve sheet tumor.

Spot-scanning proton therapy for malignant soft tissue tumors in childhood: First experiences at the Paul Scherrer Institute.

Purpose: Radiotherapy plays a major role in the treatment strategy of childhood sarcomas. Consequences of treatment are likely to affect the survivor's quality of life significantly. We investigated the feasibility of spot-scanning proton therapy (PT) for soft tissue tumors in childhood.

Extracranial chordoma: Outcome in patients treated with function-preserving surgery followed by spot-scanning proton beam irradiation.

Purpose: To evaluate the use of postoperative proton therapy (PT) in extracranial chordoma.

Patients And Methods: Twenty-six patients were treated. Gross total resection was achieved in 18 patients.

["Spot-scanning" proton therapy for rhabdomyosarcomas of early childhood. First experiences at PSI].

Purpose: To evaluate the feasibility and acute toxicity of spot-scanning proton therapy under deep sedation in young children with rhabdomyosarcomas (RMS).

Patients And Methods: Since 2004, children requiring sedation can be admitted for proton therapy at Paul Scherrer Institute (PSI), Villigen, Switzerland. Children under 5 years of age with RMS of the head and the trunk were analyzed.

Results of spot-scanning proton radiation therapy for chordoma and chondrosarcoma of the skull base: the Paul Scherrer Institut experience.

Purpose: To assess the clinical results of spot scanning proton beam radiation therapy (PT) in the treatment of skull base chordomas and low-grade chondrosarcomas (CS).

Methods And Materials: Between October 1998 and October 2003, 29 patients (median age, 39 years) with chordomas (n = 18) and CS (n = 11) were treated at the Paul Scherrer Institut (PSI) with protons using the main 510-MeV cyclotron. Tumor conformal application of proton beams was realized by spot scanning technology.

Proton beam radiotherapy versus fractionated stereotactic radiotherapy for uveal melanomas: A comparative study.

Purpose: A comparative treatment planning study was undertaken between proton and photon therapy in uveal melanoma to assess the potential benefits and limitations of these treatment modalities. A fixed proton horizontal beam (OPTIS) and intensity-modulated spot-scanning proton therapy (IMPT), with multiple noncoplanar beam arrangements, was compared with linear accelerator-based stereotactic radiotherapy (SRT), using a static and a dynamic micromultileaf collimator and intensity-modulated RT (IMRS).

Method And Materials: A planning CT scan was performed on a brain metastasis patient, with a 3-mm acquisition slice spacing and the patient looking at a luminous spot with the eyes in three different positions (neutral and 25 degrees right and left).