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Purpose To quantify radiation exposure of radiation therapy technologists (RTTs) in a proton treatment facility in comparison with a photon therapy facility, to inform and establish these specialized occupational safety guidelines. Methods and Materials Two groups of RTTs, consisting of 12 full-time passive scattering proton RTTs and 18 full-time conventional photon RTTs, wore an additional dosimetry badge at the waist for a period of 14 weeks. The 2 groups of RTTs were given identical instructions on the proper use of the badges. To compare exposures between passive scatter and scanning beam systems, exposure rates from activated equipment in both systems were measured. Results Over the 14-week period, the mean and standard deviation background-corrected dose for the passively scattered proton RTTs was 39.9 ± 5.4 mrem. The mean and standard deviation background-corrected dose for the conventional photon RTTs was similar at 39.9 ± 9.0 mrem ( P = .6). Exposure rates were lower in equipment activated in a scanning beam system in comparison with those from a passive scatter system. Conclusions Radiation dose to passively scattered proton and photon radiation therapy technologists was similar when measured with a dosimeter worn at the waist over a period of 14 weeks. On the basis of these data, the departmental policy permits pregnant radiation workers to work in proton treatment areas, and the policy for pregnant workers does not differ between proton and photon radiation workers or between passive scatter and scanning beam systems. All employees are encouraged to limit time near and proximity to activated equipment.

Background Treatment of aggressive pituitary adenomas typically involves a multimodality approach based on histopathological features and may include pharmacotherapy, surgery, and occasionally radiation therapy. In cases of treatment-refractory tumor progression, chemotherapy may be considered; however, no standard chemotherapeutic regimen has been established. Literature review suggests that temozolomide may have a beneficial role in a subset of cases. To understand the efficacy of temozolomide in progressive pituitary tumors, we reviewed the outcomes of cases at our center. Methods We performed a retrospective chart review to report the outcome and unique features of 7 patients with aggressive functioning pituitary adenomas or carcinomas treated with temozolomide. Tumor pathology included somatotroph (n = 1), corticotroph (n = 3), and lactotroph (n = 3) tumors. Results Four of the 7 patients had at least 2 prior resections, and all had prior radiation and surgery before treatment with temozolomide. Notably, all patients showed response to therapy, defined as either stable disease (43%) or partial response (57%). Median progression-free survival was 1.66 years, and median overall survival was 4 years. Conclusion Our data suggest that temozolomide has an important role in the management of aggressive functioning pituitary tumors that are resistant to standard therapies, and that optimization of therapy with temozolomide may involve individualized regimens. Future prospective clinical trials should be considered.

Purpose: The impact of nuclear reaction model differences on simulation of prompt gamma‐ray imaging for proton therapy range verification was assessed. Four nuclear reaction models were used to simulate gamma emission in proton beams, and were validated against experimental cross‐sections. Methods: Proton‐induced nuclear reactions on carbon, oxygen, nitrogen and calcium were investigated with the Monte Carlo toolkits GEANT4 9.5 and MCNPX 2.7, and the dedicated nuclear reaction codes TALYS 1.4 and EMPIRE 3.1. Absolute cross‐sections of discrete prompt gamma lines and the total gamma production were obtained for the 1–200 MeV incident proton energy range. They were compared to 34 discrete line measurements reported in literature. Using these cross‐sections, we analyzed the gamma production along the path of proton beams passing through various tissues. Results: The differences in absolute discrete line cross‐sections as predicted by the models ranged from almost zero to an order of magnitude, depending on the gamma line and incident proton energy. Overall, the dedicated nuclear reaction codes provided a better fit to most experimental excitation functions. For a 150 MeV proton beam stopping in soft tissue, these differences amount to a variation by a factor of 4 of the gamma emission around the Bragg peak location. The maximum of gamma production near the end of proton range differed by 7 mm, and the change of the 50% emission fall‐off position was 4 mm. Conclusions: There is a clear need for improvement of nuclear reaction models to accurately simulate proton range verification using prompt gamma‐rays. Current simulation codes show large uncertainties in both the total gamma yield and the correlation of gamma emission with the proton Bragg peak. GEANT4 and MCNPX in particular appear to have limited predictive power.

The metabolic genes isocitrate dehydrogenase 1 (IDH1) and IDH2 are commonly mutated in low-grade glioma and in a subset of glioblastoma. These mutations co-occur with other recurrent molecular alterations, including 1p/19q codeletions and tumor suppressor protein 53 (TP53) and alpha thalassemia/mental retardation (ATRX) mutations, which together help to define a molecular signature that aids in the classification of gliomas and helps to better predict clinical behavior. A confluence of research suggests that glioma development in IDH-mutant and IDH wild-type tumors is driven by different oncogenic processes and responds differently to current treatment paradigms. Herein, the authors discuss the discovery of IDH mutations and associated molecular alterations in glioma, review clinical features common to patients with IDH-mutant glioma, and highlight current understanding of IDH mutation-driven gliomagenesis with implications for emerging treatment strategies. Cancer 2017;123:4535-4546. © 2017 American Cancer Society.

Background The primary objective of this study was to compare the overall survival (OS) of patients with anaplastic astrocytoma (AA) treated with radiotherapy (RT) and either temozolomide (TMZ) or a nitrosourea (NU). Secondary endpoints were time to tumor progression (TTP), toxicity, and the effect of IDH1 mutation status on clinical outcome. Methods Eligible patients with centrally reviewed, histologically confirmed, newly diagnosed AA were randomized to receive either RT+TMZ (n = 97) or RT+NU (n = 99). The study closed early because the target accrual rate was not met. Results Median follow-up time for patients still alive was 10.1 years (1.9-12.6 y); 66% of the patients died. Median survival time was 3.9 years in the RT/TMZ arm (95% CI, 3.0-7.0) and 3.8 years in the RT/NU arm (95% CI, 2.2-7.0), corresponding to a hazard ratio (HR) of 0.94 (P = .36; 95% CI, 0.67-1.32). The differences in progression-free survival (PFS) and TTP between the 2 arms were not statistically significant. Patients in the RT+NU arm experienced more grade ≥3 toxicity (75.8% vs 47.9%, P < .001), mainly related to myelosuppression. Of the 196 patients, 111 were tested for IDH1-R132H status (60 RT+TMZ and 51 RT+NU). Fifty-four patients were IDH negative and 49 were IDH positive with a better OS in IDH-positive patients (median survival time 7.9 vs 2.8 y; P = .004, HR = 0.50; 95% CI, 0.31-0.81). Conclusions RT+TMZ did not appear to significantly improve OS or TTP for AA compared with RT+ NU. RT+TMZ was better tolerated. IDH1-R132H mutation was associated with longer survival.

Radiation has been used as a treatment modality for pituitary adenomas for almost half a century and can be highly effective at preventing tumor growth as well as resolving pituitary adenoma hypersecretion. Literature reporting the successful use of radiation therapy for pituitary adenomas is generally presented as retrospective series using a single radiation technique. Challenges can therefore arise when comparing the different radiation modalities described in detail below. This is particularly problematic when examining functioning adenomas and the endocrine response to radiation, as there are no standardized response criteria. These challenges are magnified by nonstandardized radiation doses and biochemical assays.

Brain metastases and primary tumors of the central nervous system (CNS) collectively impact an increasing number of cancer patients. Therefore, it is essential that practitioners understand the most common clinical concerns affecting these patients and are able to appropriately provide for their needs. The purpose of this chapter is to review the frequently utilized radiation therapy approaches, doses, and fractionation schedules for palliative CNS radiation therapy, as well as to outline the proper evaluation and management of these patients’ clinical symptoms.

Purpose To investigate [18F]-fluoromisonidazole positron emission tomography/computed tomography (FMISO-PET/CT) detection of targetable hypoxic subvolumes (HSVs) in chordoma of the mobile or sacrococcygeal spine. Methods and Materials A prospective, pilot study of 20 patients with primary or locally recurrent chordoma of the mobile or sacrococcygeal spine treated with proton or combined proton/photon radiation therapy (RT) with or without surgery was completed. The FMISO-PET/CT was performed before RT and after 19.8-34.2 GyRBE (relative biologic effectiveness). Gross tumor volumes were delineated and HSVs defined including voxels with standardized uptake values ≥1.4 times the muscle mean. Clinical characteristics and treatments received were compared between patients with and without HSVs. Results The FMISO-PET/CT detected HSVs in 12 of 20 patients (60%). Baseline and interval HSV spatial concordance varied (0%-94%). Eight HSVs were sufficiently large (≥5 cm 3 ) to potentially allow an intensity modulated proton therapy boost. Patients with HSVs had significantly larger gross tumor volumes (median 410.0 cm 3 vs 63.4 cm 3 ; P =.02) and were significantly more likely to have stage T2 tumors (5 of 12 vs 0 of 8; P =.04). After a median follow-up of 1.8 years (range, 0.2-4.4 years), a local recurrence has yet to be observed. Three patients developed metastatic disease, 2 with HSVs. Conclusions Detection of targetable HSVs by FMISO-PET/CT within patients undergoing RT with or without surgery for treatment of chordoma of the mobile and sacrococcygeal spine is feasible. The study's inability to attribute interval HSV changes to treatment, rapidly changing hypoxic physiology, or imaging inconsistencies is a limitation. Further study of double-baseline FMISO-PET/CT and hypoxia-directed RT dose escalation, particularly in patients at high risk for local recurrence, is warranted.

Purpose/Objective(s) Radiation therapy can be used to treat uveal metastases with the goal of local control and improvement of quality of life. Proton therapy can be used to treat uveal tumors efficiently and with expectant minimization of normal tissue injury. Here, we report the use of proton beam therapy for the management of uveal metastases. Methods and Materials A retrospective chart review was made of all patients with uveal metastases treated at our institution with proton therapy between June 2002 and June 2012. Patient and tumor characteristics, fractionation and dose schemes, local control, and toxicities are reported. Results Ninety patients were identified. Of those, 13 were excluded because of missing information. We report on 77 patients with 99 affected eyes with available data. Patients were 68% female, and the most common primary tumor was breast carcinoma (49%). The median age at diagnosis of uveal metastasis was 57.9 years. Serous retinal detachment was seen in 38% of treated eyes. The median follow-up time was 7.7 months. The median dose delivered to either eye was 20 Gy(relative biological effectiveness [RBE]) in 2 fractions. Local control was 94%. The median survival after diagnosis of uveal metastases was 12.3 months (95% confidence interval, 7.7-16.8). Death in all cases was secondary to systemic disease. Radiation vasculopathy, measured decreased visual acuity, or both was observed in 50% of evaluable treated eyes. The actuarial rate of radiation vasculopathy, measured decreased visual acuity, or both was 46% at 6 months and 73% at 1 year. The 6 eyes with documented local failure were successfully salvaged with retreatment. Conclusions Proton therapy is an effective and efficient means of treating uveal metastases. Acutely, the majority of patients experience minor adverse effects. For longer-term survivors, the risk of retinal injury with vision loss increases significantly over the first year.

Purpose To investigate long-term disease and toxicity outcomes for pediatric retinoblastoma patients treated with proton radiation therapy (PRT). Methods and Materials This is a retrospective analysis of 49 retinoblastoma patients (60 eyes) treated with PRT between 1986 and 2012. Results The majority (84%) of patients had bilateral disease, and nearly half (45%) had received prior chemotherapy. At a median follow-up of 8 years (range, 1-24 years), no patients died of retinoblastoma or developed metastatic disease. The post-PRT enucleation rate was low (18%), especially in patients with early-stage disease (11% for patients with International Classification for Intraocular Retinoblastoma [ICIR] stage A-B disease vs 23% for patients with ICIR stage C-D disease). Post-PRT ophthalmologic follow-up was available for 61% of the preserved eyes (30 of 49): 14 of 30 eyes (47%) had 20/40 visual acuity or better, 7 of 30 (23%) had moderate visual acuity (20/40-20/600), and 9 of 30 (30%) had little or no useful vision (worse than 20/600). Twelve of 60 treated eyes (20%) experienced a post-PRT event requiring intervention, with cataracts the most common (4 eyes). No patients developed an in-field second malignancy. Conclusions Long-term follow-up of retinoblastoma patients treated with PRT demonstrates that PRT can achieve high local control rates, even in advanced cases, and many patients retain useful vision in the treated eye. Treatment-related ocular side effects were uncommon, and no radiation-associated malignancies were observed.

This study evaluated the efficacy and toxicity of proton therapy for functional pituitary adenomas (FPAs).We analyzed 165 patients with FPAs who were treated at a single institution with proton therapy between 1992 and 2012 and had at least 6 months of follow-up. All but 3 patients underwent prior resection, and 14 received prior photon irradiation. Proton stereotactic radiosurgery was used for 92% of patients, with a median dose of 20 Gy(RBE). The remainder received fractionated stereotactic proton therapy. Time to biochemical complete response (CR, defined as ≥ 3 months of normal laboratory values with no medical treatment), local control, and adverse effects are reported.With a median follow-up time of 4.3 years (range, 0.5-20.6 years) for 144 evaluable patients, the actuarial 3-year CR rate and the median time to CR were 54% and 32 months among 74 patients with Cushing disease (CD), 63% and 27 months among 8 patients with Nelson syndrome (NS), 26% and 62 months among 50 patients with acromegaly, and 22% and 60 months among 9 patients with prolactinomas, respectively. One of 3 patients with thyroid stimulating hormone-secreting tumors achieved CR. Actuarial time to CR was significantly shorter for corticotroph FPAs (CD/NS) compared with other subtypes (P=.001). At a median imaging follow-up time of 43 months, tumor control was 98% among 140 patients. The actuarial 3-year and 5-year rates of development of new hypopituitarism were 45% and 62%, and the median time to deficiency was 40 months. Larger radiosurgery target volume as a continuous variable was a significant predictor of hypopituitarism (adjusted hazard ratio 1.3, P=.004). Four patients had new-onset postradiosurgery seizures suspected to be related to generously defined target volumes. There were no radiation-induced tumors.Proton irradiation is an effective treatment for FPAs, and hypopituitarism remains the primary adverse effect.

This study aims to demonstrate survival rates and treatment patterns among patients with chordomas of the skull base using a large population database. Patients with cranial chordomas between 1973 and 2009 were identified from the USA Surveillance, Epidemiology, and End Results (SEER) public use database. Kaplan-Meier analysis was used to examine the effect of surgery and radiation on overall survival. We identified 394 patients with histologically-confirmed cranial chordomas. Median survival was 151 months. Most patients (89.09%) underwent surgery. Less than half (44.92%) received radiation after diagnosis. Patients who underwent surgical resection survived significantly longer than those who did not undergo resection, regardless of other treatments (151 versus 81 months, p0.001). Ten year survival was lower among patients receiving radiation (44.8% versus 61.4%, p=0.66). Surgery predicted better overall survival by univariate analysis (hazard ratio [HR] 0.603, p=0.0293); younger age at diagnosis (HR 1.028, p0.001), and later year of diagnosis (HR 0.971, p=0.0027) were prognostic of improved survival in a multivariate model. In subgroup analysis of patients with documented tumor size, smaller tumor size (HR 1.021, p=0.0067), younger age (HR 1.031, p=0.001), and treatment within a higher volume registry (HR 0.490, p=0.0129) predicted improved survival. Surgical intervention offers survival benefit for cranial chordomas. Findings of decreased survival in patients receiving radiation may be associated with selection. Studies examining surgical extent of resection data and radiation details are needed to determine the impact of radiotherapy.

Neoplasia is uncommon in Turner syndrome, although there is some evidence that brain tumors are more common in Turner syndrome patients than in the general population. We describe a woman with Turner syndrome (45,X) with a meningioma, in whom a second neoplasia, basal cell carcinomas of the scalp and nose, developed five years later in the absence of therapeutic radiation. Together with 7 cases of Turner syndrome with meningioma from a population-based survey in the United Kingdom, and 3 other isolated cases in the literature, we review this small number of patients for evidence of risk factors related to Turner syndrome, such as associated structural anomalies or prior treatment. We performed histological and fluorescent in situ hybridization (FISH) of 22q (NF2 locus) analyses of the meningeal tumor to search for possible molecular determinants. We are not able to prove causation between these two entities, but suggest that neoplasia may be a rare associated medical problem in Turner syndrome. Additional case reports and extension of population-based studies are needed.

Purpose Vestibular schwannomas (VS) are often followed without initial therapeutic intervention because many tumors do not grow and radiation therapy is associated with potential adverse effects. In an effort to determine whether maximizing initial surveillance predicts for later treatment response, the predictive value of preirradiation growth rate of VS on response to radiation therapy was assessed. Methods and Materials Sixty-four patients with 65 VS were treated with single-fraction stereotactic radiation surgery or fractionated stereotactic radiation therapy. Pre- and postirradiation linear expansion rates were estimated using volumetric measurements on sequential magnetic resonance images (MRIs). In addition, postirradiation tumor volume change was classified as demonstrating shrinkage (ratio of volume on last follow-up MRI to MRI immediately preceding irradiation 120%). The median pre- and postirradiation follow-up was 20.0 and 27.5 months, respectively. Seven tumors from neurofibromatosis type 2 (NF2) patients were excluded from statistical analyses. Results In the 58 non-NF2 patients, there was a trend of correlation between pre- and postirradiation volume change rates (slope on linear regression, 0.29; P =.06). Tumors demonstrating postirradiation expansion had a median preirradiation growth rate of 89%/year, and those without postirradiation expansion had a median preirradiation growth rate of 41%/year ( P =.02). As the preirradiation growth rate increased, the probability of postirradiation expansion also increased. Overall, 24.1% of tumors were stable, 53.4% experienced shrinkage, and 22.5% experienced expansion. Predictors of no postirradiation tumor expansion included no prior surgery ( P =.01) and slower tumor growth rate ( P =.02). The control of tumors in NF2 patients was only 43%. Conclusions Radiation therapy is an effective treatment for VS, but tumors that grow quickly preirradiation may be more likely to increase in size. Clinicians should take into account tumor growth rate when counseling patients about treatment options.

Gliomas differ from many other tumors as they grow infiltratively into the brain parenchyma rather than forming a solid tumor mass with a well-defined boundary. Tumor cells can be found several centimeters away from the central tumor mass that is visible using current imaging techniques. The infiltrative growth characteristics of gliomas question the concept of a radiotherapy target volume that is irradiated to a homogeneous dose-the standard in current clinical practice. We discuss the use of the Fisher-Kolmogorov glioma growth model in radiotherapy treatment planning. The phenomenological tumor growth model assumes that tumor cells proliferate locally and migrate into neighboring brain tissue, which is mathematically described via a partial differential equation for the spatio-temporal evolution of the tumor cell density. In this model, the tumor cell density drops approximately exponentially with distance from the visible gross tumor volume, which is quantified by the infiltration length, a parameter describing the distance at which the tumor cell density drops by a factor of e. This paper discusses the implications for the prescribed dose distribution in the periphery of the tumor. In the context of the exponential cell kill model, an exponential fall-off of the cell density suggests a linear fall-off of the prescription dose with distance. We introduce the dose fall-off rate, which quantifies the steepness of the prescription dose fall-off in units of Gy mm(-1). It is shown that the dose fall-off rate is given by the inverse of the product of radiosensitivity and infiltration length. For an infiltration length of 3 mm and a surviving fraction of 50% at 2 Gy, this suggests a dose fall-off of approximately 1 Gy mm(-1). The concept is illustrated for two glioblastoma patients by optimizing intensity-modulated radiotherapy plans. The dose fall-off rate concept reflects the idea that infiltrating gliomas lack a defined boundary and are characterized by a continuous fall-off of the density of infiltrating tumor cells. The approach can potentially be used to individualize the prescribed dose distribution if better methods to estimate radiosensitivity and infiltration length on a patient by patient basis become available.

BACKGROUND The leading cause of death among patients with hereditary retinoblastoma is second malignancy. Despite its high rate of efficacy, radiotherapy (RT) is often avoided due to fear of inducing a secondary tumor. Proton RT allows for significant sparing of nontarget tissue. The current study compared the risk of second malignancy in patients with retinoblastoma who were treated with photon and proton RT. METHODS A retrospective review was performed of patients with retinoblastoma who were treated with proton RT at the Massachusetts General Hospital or photon RT at Boston Children's Hospital between 1986 and 2011. RESULTS A total of 86 patients were identified, 55 of whom received proton RT and 31 of whom received photon RT. Patients were followed for a median of 6.9 years (range, 1.0 years-24.4 years) in the proton cohort and 13.1 years (range, 1.4 years-23.9 years) in the photon cohort. The 10-year cumulative incidence of RT-induced or in-field second malignancies was significantly different between radiation modalities (proton vs photon: 0% vs 14%; P = .015). The 10-year cumulative incidence of all second malignancies was also different, although with borderline significance (5% vs 14%; P = .120). CONCLUSIONS Retinoblastoma is highly responsive to radiation. The central objection to the use of RT, the risk of second malignancy, is based on studies of patients treated with antiquated, relatively nonconformal techniques. The current study is, to the authors' knowledge, the first to present a series of patients treated with the most conformal of the currently available external-beam RT modalities. Although longer follow-up is necessary, the preliminary data from the current study suggest that proton RT significantly lowers the risk of RT-induced malignancy. Cancer 2014;120:126–133. © 2013 American Cancer Society.

Patients with World Health Organization (WHO) grade II supratentorial ependymomas are commonly observed after gross total resection (GTR), although supporting data are limited. We sought to characterize the natural history of such tumors. We used the Surveillance, Epidemiology, and End Results program to identify 112 patients ages 0-77 diagnosed with WHO grade II ependymomas between 1988 and 2007, of whom 63 (56 %) and 49 (44 %) had supratentorial and infratentorial primaries, respectively. Inclusion criteria were strict to ensure patient homogeneity. Of 33 patients with supratentorial tumors after GTR, 18 (55 %) received adjuvant radiation therapy and 15 (45 %) did not. Ependymoma-specific mortality (ESM) was the primary endpoint. With a median follow up of 4.5 years, only 1 of 33 patients with supratentorial ependymoma died of their disease after GTR; the 5-year estimate of ESM in this population was 3.3 % (95 % CI 0.2-14.8 %). Among patients with infratentorial ependymomas after GTR, the 5-year estimate of ESM was 8.7 % (95 % CI 1.4-24.6 %). In patients with subtotally resected tumors, 5-year estimates of ESM in patients with supratentorial and infratentorial primaries were 20.1 % (95 % CI 8.0-36.2 %) and 12.3 % (95 % CI 2.9-28.8 %), respectively. Among the whole cohort, on both univariable and multivariable regression, extent of resection was predictive of ESM, while tumor location and use of radiation were not. After GTR, patients with WHO grade II supratentorial ependymomas have a very favorable natural history with low associated cancer-specific mortality. Observation, with radiation reserved as a salvage option, may be a reasonable postoperative strategy in this population.

Purpose The purpose of this study is to evaluate the potential of using in-room positron emission tomography (PET) for treatment verification in proton therapy and for deriving suitable PET scan times. Methods and Materials Nine patients undergoing passive scattering proton therapy underwent scanning immediately after treatment with an in-room PET scanner. The scanner was positioned next to the treatment head after treatment. The Monte Carlo (MC) method was used to reproduce PET activities for each patient. To assess the proton beam range uncertainty, we designed a novel concept in which the measured PET activity surface distal to the target at the end of range was compared with MC predictions. The repositioning of patients for the PET scan took, on average, approximately 2 minutes. The PET images were reconstructed considering varying scan times to test the scan time dependency of the method. Results The measured PET images show overall good spatial correlations with MC predictions. Some discrepancies could be attributed to uncertainties in the local elemental composition and biological washout. For 8 patients treated with a single field, the average range differences between PET measurements and computed tomography (CT) image-based MC results were Conclusions Our first clinical trials in 9 patients using an in-room PET system demonstrated its potential for in vivo treatment monitoring in proton therapy. For a quantitative range prediction with arbitrary shape of target volume, we suggest using the distal PET activity surface.

Our group has previously published the Diagnosis-Specific Graded Prognostic Assessment (GPA) showing the prognostic factors associated with survival in patients with brain metastases (BM). The purpose of this study is to investigate the relationship of breast cancer subtype to the time interval from primary diagnosis (PD) to development of BM (TPDBM), number of BM at initial BM presentation and survival. We analyzed our previously described multi-institutional retrospective database of 865 breast cancer patients treated for newly-diagnosed BM from 1993 to 2010. Several factors found to be associated with survival were incorporated into the Breast-GPA, including tumor subtype. The GPA database was further analyzed to determine if the subtype correlated with the TPDBM, number of BM, and survival from PD. After exclusions for incomplete data, 383 patients remained eligible for analysis. The subtypes were approximated as follows: Luminal B: triple positive; HER2: HER2 positive/ER/PR negative; Luminal A; ER/PR positive/HER2 negative; Basal: triple negative. Patients with Basal (90), HER2 (119), Luminal B (98) and Luminal A (76) tumor subtypes had a median TPDBM of 27.5, 35.8, 47.4 and 54.4 months (p < 0.01), median survival from PD of 39.6, 66.4, 90.3 and 72.7 months (p < 0.01) and median survival from BM of 7.3, 17.9, 22.9 and 10.0 months (p < 0.01), respectively. Tumor subtype is an important prognostic factor for survival in patients with breast cancer and BM. Although TPDBM is not an independent prognostic factor for survival (and thus not part of the Breast-GPA), the TPDBM does correlate with tumor subtype but does not correlate with the number of BM. Patients with Basal and HER2 tumor subtypes have short TPDBM. Prospective studies are needed to determine if screening brain MRIs are indicated in patients with Basal or HER2 subtypes.

The role for adjuvant radiation therapy following surgical resection in the treatment of malignant gliomas is currently guided by the tumor histology and, increasingly, by the molecular genetic features. The standard of care for patients with glioblastoma is adjuvant radiation therapy with concomitant and subsequent temozolomide. For patients who are elderly and/or have a poor performance status, single modality approaches with radiation, including shorter-course regimens or temozolomide alone are reasonable. Anaplastic astrocytomas are treated similarly to glioblastoma with adjuvant chemoradiation. The role for radiation therapy for patients with anaplastic oligodendrogliomas is under active investigation given the chemosensitivity of these tumors. The optimal adjuvant therapy for low-grade gliomas is individualized and often dependent on a patient’s risk factors.

Introduction:Treatment of aggressive pituitary adenomas typically involves a multimodality approach based on histopathological features and may include pharmacotherapy, surgery and radiation therapy. In cases of treatment-refractory tumor progression, chemotherapy may be considered. However, no standard chemotherapeutic regimen has been established. Anecdotal reports suggest that temozolomide may have a beneficial role in a subset of cases.Materials and Methods:In this case series and institutional experience we report the outcome and unique clinical characteristics of seven patients with aggressive pituitary tumors treated with temozolomide given at various dose regimens.Results:Tumor pathology included somatotrope (n=1), corticotrope (n=3), and lactotrope (n=3) tumors. Four of the seven patients had at least two prior resections, and all had prior radiation and surgery before treatment with temozolomide was considered. Notably, all patients showed response to therapy, defined as either stable disease (43%) or partial response (57%), using standard tumor response assessment parameters. Excluding the two patients who remain on therapy to date, total duration of therapeutic benefit ranged between 5–15 months. Three patients showed radiographic and clinical benefit beyond one year.Conclusions:Our data suggest that temozolomide may have an important role in the management of aggressive functioning pituitary tumors that are resistant to standard therapies, and that optimization of therapy with temozolomide may involve individualized regimens. Future prospective clinical trials should be considered.

Background Gliomas with mutant isocitrate dehydrogenase (IDH) produce high levels of 2-hydroxyglutarate (2HG) that can be quantitatively measured by 3D magnetic resonance spectroscopic imaging (MRSI). Current glioma MRI primarily relies upon fluid-attenuated inversion recovery (FLAIR) hyperintensity for treatment planning, although this lacks specificity for tumor cells. Here, we investigated the relationship between 2HG and FLAIR in mutant IDH glioma patients to determine whether 2HG mapping is valuable for radiotherapy planning. Methods Seventeen patients with mutant IDH1 gliomas were imaged by 3 T MRI. A 3D MRSI sequence was employed to specifically image 2HG. FLAIR imaging was performed using standard clinical protocol. Regions of interest (ROIs) were determined for FLAIR and optimally thresholded 2HG hyperintensities. The overlap, displacement, and volumes of 2HG and FLAIR ROIs were calculated. Results In 8 of 17 (47%) patients, the 2HG volume was larger than FLAIR volume. Across the entire cohort, the mean volume of 2HG was 35.3 cc (range, 5.3-92.7 cc), while the mean volume of FLAIR was 35.8 cc (range, 6.3-140.8 cc). FLAIR and 2HG ROIs had mean overlap of 0.28 (Dice coefficients range, 0.03-0.57) and mean displacement of 12.2 mm (range, 3.2-23.5 mm) between their centers of mass. Conclusions Our results indicate that for a substantial number of patients, the 2HG volumetric assessment of tumor burden is more extensive than FLAIR volume. In addition, there is only partial overlap and asymmetric displacement between the centers of FLAIR and 2HG ROIs. These results may have important implications for radiotherapy planning of IDH mutant glioma.

Purpose To present evidence-based guidelines for radiation therapy in treating glioblastoma not arising from the brainstem. Methods and materials The American Society for Radiation Oncology (ASTRO) convened the Glioblastoma Guideline Panel to perform a systematic literature review investigating the following: (1) Is radiation therapy indicated after biopsy/resection of glioblastoma and how does systemic therapy modify its effects? (2) What is the optimal dose-fractionation schedule for external beam radiation therapy after biopsy/resection of glioblastoma and how might treatment vary based on pretreatment characteristics such as age or performance status? (3) What are ideal target volumes for curative-intent external beam radiation therapy of glioblastoma? (4) What is the role of reirradiation among glioblastoma patients whose disease recurs following completion of standard first-line therapy? Guideline recommendations were created using predefined consensus-building methodology supported by ASTRO-approved tools for grading evidence quality and recommendation strength. Results Following biopsy or resection, glioblastoma patients with reasonable performance status up to 70 years of age should receive conventionally fractionated radiation therapy (eg, 60 Gy in 2-Gy fractions) with concurrent and adjuvant temozolomide. Routine addition of bevacizumab to this regimen is not recommended. Elderly patients (≥70 years of age) with reasonable performance status should receive hypofractionated radiation therapy (eg, 40 Gy in 2.66-Gy fractions); preliminary evidence may support adding concurrent and adjuvant temozolomide to this regimen. Partial brain irradiation is the standard paradigm for radiation delivery. A variety of acceptable strategies exist for target volume definition, generally involving 2 phases (primary and boost volumes) or 1 phase (single volume). For recurrent glioblastoma, focal reirradiation can be considered in younger patients with good performance status. Conclusions Radiation therapy occupies an integral role in treating glioblastoma. Whether and how radiation therapy should be applied depends on characteristics specific to tumor and patient, including age and performance status.

Background/Aim: Unilateral choroidal infiltration as the initial manifestation of leukemic relapse in adults is rare, particularly after an extended period of remission. This report describes this unique ophthalmic presentation, highlights the associated diagnostic challenges, and reviews the literature. Methods: Two cases are described and an extensive literature review was conducted. Results: A 59-year-old male with acute lymphoid leukemia, in remission for 18 months, presented with unilateral scleritis, exudative retinal detachment, and choroidal thickening. A 57-year-old male with a history of acute myeloid leukemia, in remission for 4 years, presented with unilateral choroidal thickening leading to secondary angle closure. In both cases, there was a significant lag from the onset of eye symptoms to establishing a systemic diagnosis of acute leukemia, leading to a delay in definitive systemic treatment, despite a high suspicion of disease based on ophthalmic findings. Conclusions: These two cases illustrate the fundus findings consistent with leukemic choroidal infiltration that can represent the first sign of relapsed leukemia. The successful treatment of these patients hinges on collaboration between ophthalmologists and oncologists to optimize patient outcomes, highlighting the need for both groups to be aware of this rare ophthalmic presentation.

The measurement of prompt gamma rays emitted from proton-induced nuclear reactions has been proposed as a method to verify in vivo the range of a clinical proton radiotherapy beam. A good understanding of the prompt gamma-ray emission during proton therapy is key to develop a clinically feasible technique, as it can facilitate accurate simulations and uncertainty analysis of gamma detector designs. Also, the gamma production cross-sections may be incorporated as prior knowledge in the reconstruction of the proton range from the measurements. In this work, we performed simulations of proton-induced nuclear reactions with the main elements of human tissue, carbon-12, oxygen-16 and nitrogen-14, using the nuclear reaction models of the GEANT4 and MCNP6 Monte Carlo codes and the dedicated nuclear reaction codes TALYS and EMPIRE. For each code, we made an effort to optimize the input parameters and model selection. The results of the models were compared to available experimental data of discrete gamma line cross-sections. Overall, the dedicated nuclear reaction codes reproduced the experimental data more consistently, while the Monte Carlo codes showed larger discrepancies for a number of gamma lines. The model differences lead to a variation of the total gamma production near the end of the proton range by a factor of about 2. These results indicate a need for additional theoretical and experimental study of proton-induced gamma emission in human tissue.

Purpose To evaluate patients with high-risk cerebral arteriovenous malformations (AVMs), based on eloquent brain location or large size, who underwent planned two-fraction proton stereotactic radiosurgery (PSRS). Methods and Materials From 1991 to 2009, 59 patients with high-risk cerebral AVMs received two-fraction PSRS. Median nidus volume was 23 cc (range, 1.4–58.1 cc), 70% of cases had nidus volume ≥14 cc, and 34% were in critical locations (brainstem, basal ganglia). Median AVM score based on age, AVM size, and location was 3.19 (range, 0.9–6.9). Many patients had prior surgery or embolization (40%) or prior PSRS (12%). The most common prescription was 16 Gy radiobiologic equivalent (RBE) in two fractions, prescribed to the 90% isodose. Results At a median follow-up of 56.1 months, 9 patients (15%) had total and 20 patients (34%) had partial obliteration. Patients with total obliteration received higher total dose than those with partial or no obliteration (mean dose, 17.6 vs. 15.5 Gy (RBE), p = 0.01). Median time to total obliteration was 62 months (range, 23–109 months), and 5-year actuarial rate of partial or total obliteration was 33%. Five-year actuarial rate of hemorrhage was 22% (95% confidence interval, 12.5%–36.8%) and 14% ( n = 8) suffered fatal hemorrhage. Lesions with higher AVM scores were more likely to hemorrhage ( p = 0.024) and less responsive to radiation ( p = 0.026). The most common complication was Grade 1 headache acutely (14%) and long term (12%). One patient developed a Grade 2 generalized seizure disorder, and two had mild neurologic deficits. Conclusions High-risk AVMs can be safely treated with two-fraction PSRS, although total obliteration rate is low and patients remain at risk for future hemorrhage. Future studies should include higher doses or a multistaged PSRS approach for lesions more resistant to obliteration with radiation.

The diagnosis-specific Graded Prognostic Assessment (GPA) was published to clarify prognosis for patients with brain metastases. This study refines the existing Breast-GPA by analyzing a larger cohort and tumor subtype.A multi-institutional retrospective database of 400 breast cancer patients treated for newly diagnosed brain metastases was generated. Prognostic factors significant for survival were analyzed by multivariate Cox regression and recursive partitioning analysis (RPA). Factors were weighted by the magnitude of their regression coefficients to define the GPA index.Significant prognostic factors by multivariate Cox regression and RPA were Karnofsky performance status (KPS), HER2, ER/PR status, and the interaction between ER/PR and HER2. RPA showed age was significant for patients with KPS 60 to 80. The median survival time (MST) overall was 13.8 months, and for GPA scores of 0 to 1.0, 1.5 to 2.0, 2.5 to 3.0, and 3.5 to 4.0 were 3.4 (n = 23), 7.7 (n = 104), 15.1 (n = 140), and 25.3 (n = 133) months, respectively (p0.0001). Among HER2-negative patients, being ER/PR positive improved MST from 6.4 to 9.7 months, whereas in HER2-positive patients, being ER/PR positive improved MST from 17.9 to 20.7 months. The log-rank statistic (predictive power) was 110 for the Breast-GPA vs. 55 for tumor subtype.The Breast-GPA documents wide variation in prognosis and shows clear separation between subgroups of patients with breast cancer and brain metastases. This tool will aid clinical decision making and stratification in clinical trials. These data confirm the effect of tumor subtype on survival and show the Breast-GPA offers significantly more predictive power than the tumor subtype alone.

Purpose Patients with brain metastases are often treated with whole brain radiation therapy (WBRT) for purposes of palliation. The treatment of those who experience subsequent intracranial disease progression can include a second course of WBRT, although there is controversy surrounding its safety and efficacy. This study examines the outcomes in patients at Massachusetts General Hospital who underwent reirradiation. Patients and Methods We examined the medical records of 17 patients at Massachusetts General Hospital with brain metastases who were initially treated with WBRT between 2002 and 2008 and were subsequently retreated with a second course of WBRT. The median dose for the first course of WBRT was 35 Gy (range, 28–40 Gy), with a fraction size of 2 to 3 Gy (median, 2.5 Gy). The median dose at reirradiation was 21.6 Gy (range, 14–30 Gy), with a fraction size of 1.5 to 2 Gy (median, 1.8 Gy). Results The second course of WBRT was administered upon radiographic disease progression in all patients. Of 10 patients with complete follow-up data, 8 patients experienced complete or partial symptom resolution, and 2 did not show clinical improvement. The time to radiographic progression was 5.2 months. The median overall survival for all patients after diagnosis of metastases was 24.7 months. The median survival time after initiation of reirradiation was 5.2 months (95% CI, 1.3–8.7). In 6 patients with stable extracranial disease, the median survival time after retreatment was 19.8 months (95% CI, 2.7–∞), compared with 2.5 months (95% CI, 0.8–5.5) for those with extracranial disease progression ( p = 0.05). Acute adverse reactions occurred in 70.5% of patients but were mild to moderate in severity. Conclusion In select patients and especially those with stable extracranial disease, reirradiation may be an appropriate and effective intervention to provide symptomatic relief and slow intracranial disease progression. Side effects were minimal and did not cause substantial changes in quality of life.

Purpose To test whether multicriteria optimization (MCO) can reduce treatment planning time and improve plan quality in intensity-modulated radiotherapy (IMRT). Methods and Materials Ten IMRT patients (5 with glioblastoma and 5 with locally advanced pancreatic cancers) were logged during the standard treatment planning procedure currently in use at Massachusetts General Hospital (MGH). Planning durations and other relevant planning information were recorded. In parallel, the patients were planned using an MCO planning system, and similar planning time data were collected. The patients were treated with the standard plan, but each MCO plan was also approved by the physicians. Plans were then blindly reviewed 3 weeks after planning by the treating physician. Results In all cases, the treatment planning time was vastly shorter for the MCO planning (average MCO treatment planning time was 12 min; average standard planning time was 135 min). The physician involvement time in the planning process increased from an average of 4.8 min for the standard process to 8.6 min for the MCO process. In all cases, the MCO plan was blindly identified as the superior plan. Conclusions This provides the first concrete evidence that MCO-based planning is superior in terms of both planning efficiency and dose distribution quality compared with the current trial and error–based IMRT planning approach.

This study was designed to estimate the risk of radiation-associated tumors and clinical toxicity in the brain following fractionated radiation treatment of pituitary adenoma. A standard case of a patient with a pituitary adenoma was planned using 8 different dosimetric techniques. Total dose was 50.4 Gy (GyE) at daily fractionation of 1.8 Gy (GyE). All methods utilized the same CT simulation scan with designated target and normal tissue volumes. The excess risk of radiation-associated second tumors in the brain was calculated using the corresponding dose-volume histograms for the whole brain and based on the data published by the United Nation Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and a risk model proposed by Schneider. The excess number of second tumor cases per 10,000 patients per year following radiation is 9.8 for 2-field photons, 18.4 with 3-field photons, 20.4 with photon intensity modulated radiation therapy (IMRT), and 25 with photon stereotactic radiotherapy (SRT). Proton radiation resulted in the following excess second tumor risks: 2-field = 5.1, 3-field = 12, 4-field = 15, 5-field = 16. Temporal lobe toxicity was highest for the 2-field photon plan. Proton radiation therapy achieves the best therapeutic ratio when evaluating plans for the treatment of pituitary adenoma. Temporal lobe toxicity can be reduced through the use of multiple fields but is achieved at the expense of exposing a larger volume of normal brain to radiation. Limiting the irradiated volume of normal brain by reducing the number of treatment fields is desirable to minimize excess risk of radiation-associated second tumors.