Patterns of failure in pediatric medulloblastoma and implications for hippocampal sparing.

BACKGROUND: Hippocampal avoidance (HA) has been shown to preserve cognitive function in adult patients with cancer treated with whole-brain radiation therapy for brain metastases. However, the feasibility of HA in pediatric patients with brain tumors has not been explored because of concerns of increased risk of relapse in the peri-hippocampal region. Our aim was to determine patterns of recurrence and incidence of peri-hippocampal relapse in pediatric patients with medulloblastoma (MB). METHODS AND MATERIALS: We identified pediatric patients with MB treated with protons between 2002 and 2016 and who had recurrent disease. To estimate the risk of peri-hippocampal recurrence, three hippocampal zones (HZs) were delineated corresponding to ≤5 mm (HZ-1), 6 to 10 mm (HZ-2), and >10 mm (HZ-3) distance of the recurrence from the contoured hippocampi. To determine the feasibility of HA, three standard-risk patients with MB were planned using either volumetric-modulated arc therapy (VMAT) or intensity-modulated proton therapy (IMPT) plans. RESULTS: Thirty-eight patients developed a recurrence at a median of 1.6 years. Of the 25 patients who had magnetic resonance imaging of the recurrence, no patients failed within the hippocampus and only two patients failed within HZ-1. The crude incidence of peri-hippocampal failure was 8%. Both HA-VMAT and HA-IMPT plans were associated with significantly reduced mean dose to the hippocampi (p < .05). HA-VMAT and HA-IMPT plans were associated with decreased percentage of the third and lateral ventricles receiving the prescription craniospinal dose of 23.4 Gy. CONCLUSIONS: Peri-hippocampal failures are uncommon in pediatric patients with MB. Hippocampal avoidance should be evaluated in a prospective cohort of pediatric patients with MB. PLAIN LANGUAGE SUMMARY: In this study, the patterns of disease recurrence in patients with a pediatric brain tumor known as medulloblastoma treated with proton radiotherapy were examined. The majority of failures occur outside of an important structure related to memory formation called the hippocampus. Hippocampal sparing radiation plans using proton radiotherapy were generated and showed that dose to the hippocampus was able to be significantly reduced. The study provides the rationale to explore hippocampal sparing in pediatric medulloblastoma in a prospective clinical trial.

Long-term outcomes and late toxicity of adult medulloblastoma treated with combined modality therapy: A contemporary single-institution experience.

BACKGROUND: Medulloblastoma (MB) is a rare central nervous system malignancy of adults, with limited contemporary studies to define treatment guidelines and expected late toxicity. METHODS: A single-center, retrospective study was conducted of patients age ≥18 years from 1997-2019 with MB and who were treated with postoperative radiotherapy. Late toxicity was defined as a minimum of 18 months from diagnosis. Overall survival (OS) and progression-free survival (PFS) were characterized using Kaplan-Meier and Cox regression analyses. RESULTS: Fifty-nine patients met criteria, with median age of 25 years (range 18-62 y) and median follow-up of 6.5 years (range 0.7-23.1 y). At diagnosis, 68% were standard-risk, 88% Chang M0, and 22% with anaplastic histology. Gross total resection was achieved in 75%; median craniospinal irradiation dose was 30.6 Gy (relative biological effectiveness [RBE]), median total dose was 54.0 Gy (RBE), 80% received proton radiotherapy; 81% received chemotherapy. 5 year PFS and OS were 86.5% and 95.8%, respectively; 10 year PFS and OS were 83.9% and 90.7%, respectively. Anaplastic histology was associated with worse PFS (P = .04). Among eight recurrences, 25% presented after 5 years. Most common grade ≥2 late toxicities were anxiety/depressive symptoms (30%), motor dysfunction (25%), and ototoxicity (22%). Higher posterior fossa radiation dose was associated with increased risk of late toxicity, including worse cognitive dysfunction (P = .05). CONCLUSIONS: Adults with MB have favorable survival outcomes, but late failures and toxicity are not uncommon. Better understanding of prognostic factors, possibly from molecular subtyping, may help to define more personalized treatments for patients with high risk of recurrence and long-term treatment sequelae.

Genome-wide DNA methylation patterns reveal clinically relevant predictive and prognostic subtypes in human osteosarcoma.

Aberrant methylation of genomic DNA has been reported in many cancers. Specific DNA methylation patterns have been shown to provide clinically useful prognostic information and define molecular disease subtypes with different response to therapy and long-term outcome. Osteosarcoma is an aggressive malignancy for which approximately half of tumors recur following standard combined surgical resection and chemotherapy. No accepted prognostic factor save tumor necrosis in response to adjuvant therapy currently exists, and traditional genomic studies have thus far failed to identify meaningful clinical associations. We studied the genome-wide methylation state of primary tumors and tested how they predict patient outcomes. We discovered relative genomic hypomethylation to be strongly predictive of response to standard chemotherapy. Recurrence and survival were also associated with genomic methylation, but through more site-specific patterns. Furthermore, the methylation patterns were reproducible in three small independent clinical datasets. Downstream transcriptional, in vitro, and pharmacogenomic analysis provides insight into the clinical translation of the methylation patterns. Our findings suggest the assessment of genomic methylation may represent a strategy for stratifying patients for the application of alternative therapies.

Intellectual functioning among case-matched cohorts of children treated with proton or photon radiation for standard-risk medulloblastoma.

BACKGROUND: Proton therapy may reduce cognitive deficits after radiotherapy among brain tumor survivors, although current data are limited to retrospective comparisons between historical cohorts. The authors compared intelligence quotient scores within a case-matched cohort of children with medulloblastoma treated with proton radiation (PRT) or photon radiation (XRT) over the same time period. METHODS: Among 88 consecutive patients with standard-risk medulloblastoma treated with PRT or XRT at 2 institutions from 2000 to 2009, 50 were matched 1:1 (25 with PRT and 25 with XRT) according to age, gender, date of diagnosis, histology, radiation boost, and craniospinal irradiation dose. One-way analyses of variance were performed to compare the Full-Scale Intelligence Quotient (FSIQ) and associated index scores between the 2 cohorts. RESULTS: Neurocognitive data were available for 37 survivors (17 with PRT and 20 with XRT) from the matched cohort. The mean age was 8.5 years (SD, 4.14 years). The median follow-up was 5.3 years (range, 1.0-11.4 years) and 4.6 years (range, 1.1-11.2 years) for the PRT and XRT cohorts, respectively (P = .193). Patients treated with PRT had significantly higher mean FSIQ (99.6 vs 86.2; P = .021), verbal (105.2 vs 88.6; P = .010), and nonverbal scores (103.1 vs 88.9; P = .011) than the XRT-treated cohort. Differences in processing speed (82.9 vs 77.2; P = .331) and working memory (97.0 vs 92.7; P = .388) were not statistically significant. CONCLUSIONS: Radiotherapy-associated cognitive effects appear to be more attenuated after proton therapy. Comprehensive prospective studies are needed to appropriately evaluate the neurocognitive advantages of proton therapy.

Clinical outcomes of pediatric patients with autism spectrum disorder and other neurodevelopmental disorders and intracranial germ cell tumors.

INTRODUCTION: Intracranial germ cell tumors (IGCTs) are rare tumors of the central nervous system with peak incidence around puberty. Given the developmental origins of IGCTs, we investigated the prevalence of neurodevelopmental disorders (NDDs) in patients with IGCTs and characterized outcomes for patients with NDD and IGCTs. METHODS: A retrospective review of medical records was conducted for 111 patients diagnosed with IGCTs between 1998 and 2018 and evaluated at the Massachusetts General Hospital. Kaplan-Meier method and log-rank test was used for survival analyses. Cox regression analyses were performed for parameters associated with progression-free survival (PFS). RESULTS: Median age at IGCT diagnosis was 12.8 years (range: 4.3-21.7) and median follow-up was 6.5 years (range: 0.2-20.5). Eighteen patients were diagnosed with NDDs prior to IGCT diagnosis, including five patients with autism spectrum disorder (ASD). Of the 67 patients with pure germinomas, four (6.0 %) had prior ASD diagnoses. Patients with NDD had significantly inferior PFS in the nongerminomatous germ cell tumor (NGGCT) cohort. On univariate and multivariable analyses, craniospinal irradiation (CSI) was significantly associated with improved PFS in the NGGCT cohort. CONCLUSIONS: Our study found an ASD prevalence in the pure germinoma cohort more than threefold greater than the national prevalence, suggesting an association between ASD and pure germinomas. Furthermore, patients with NDD and NGGCT had worse PFS, possibly due to fewer patients with NDD receiving CSI. Future prospective studies with larger cohorts are needed to examine associations between NDDs and IGCTs, and further characterize outcomes for patients with NDDs and IGCTs.

Circulating Lymphocyte Counts Early During Radiation Therapy Are Associated With Recurrence in Pediatric Medulloblastoma.

PURPOSE: Decreased peripheral lymphocyte counts are associated with survival after radiation therapy (RT) in several solid tumors, although they appear late during or after the radiation course and often correlate with other clinical factors. Here we investigate if absolute lymphocyte counts (ALCs) are independently associated with recurrence in pediatric medulloblastoma early during RT. METHODS AND MATERIALS: We assessed 202 patients with medulloblastoma treated between 2000 and 2016 and analyzed ALC throughout therapy, focusing on both early markers (ALC during week 1 - ALCwk1; grade 3+ Lymphopenia during week 2 - Lymphopeniawk2) and late markers (ALC nadir). Uni- and multivariable regressions were used to assess association of clinical and treatment variables with ALC and of ALC with recurrence. RESULTS: Thirty-six recurrences were observed, with a median time to recurrence of 1.6 years (range, 0.2-10.3) and 7.1 years median follow-up. ALC during RT was associated with induction chemotherapy (P < .001), concurrent carboplatin (P = .009), age (P = .01), and high-risk status (P = .05). On univariable analysis, high-risk disease (hazard ratio = 2.0 [1.06-3.9]; P = .03) and M stage≥1 (hazard ratio = 2.2 [1.1-4.4]) were associated with recurrence risk, as was lower ALC early during RT (ALCwk1, hazard ratio = 0.28 [0.12-0.65]; P = .003; Lymphopeniawk2, hazard ratio = 2.27 [1.1-4.6]; P = .02). Neither baseline ALC nor nadir correlated with outcome. These associations persisted when excluding carboplatin and pre-RT chemotherapy patients, and in the multivariable analysis accounting for confounders lymphocyte counts remained significant (ALCwk1, hazard-ratio = 0.23 [0.09-0.57]; P = .002; Lymphopeniawk2, hazard-ratio = 2.3 [1.1-4.8]; P = .03). CONCLUSIONS: ALC during weeks 1 and 2 of RT was associated with recurrence, and low ALC is an independent prognostic factor in medulloblastoma. Strategies to mitigate the risk of radiation-induced lymphopenia should be considered.

Clinical outcomes in a large pediatric cohort of patients with ependymoma treated with proton radiotherapy.

BACKGROUND: Treatment for pediatric ependymoma includes surgical resection followed by local radiotherapy (RT). Proton RT (PRT) enables superior sparing of critical structures compared with photons, with potential to reduce late effects. We report mature outcomes, patterns of failure, and predictors of outcomes in patients treated with PRT. METHODS: One hundred fifty patients (<22 y) with World Health Organization grades II/III ependymoma were treated with PRT between January 2001 and January 2019 at Massachusetts General Hospital. Demographic, tumor, and treatment-related characteristics were analyzed. Event-free survival (EFS), overall survival (OS), and local control (LC) were assessed. RESULTS: Median follow-up was 6.5 years. EFS, OS, and LC for the intracranial cohort (n = 145) at 7 years were 63.4%, 82.6%, and 76.1%. Fifty-one patients recurred: 26 (51.0%) local failures, 19 (37.3%) distant failures, and 6 (11.8%) synchronous failures. One hundred sixteen patients (77.3%) underwent gross total resection (GTR), 5 (3.3%) underwent near total resection (NTR), and 29 (19.3%) underwent subtotal resection (STR). EFS for the intracranial cohort at 7 years for GTR/NTR and STR was 70.3% and 35.2%. With multivariate analysis, the effect of tumor excision persisted after controlling for tumor location. There was no adverse effect on disease control if surgery to RT interval was within 9 weeks of GTR/NTR. CONCLUSION: PRT is effective and safe in pediatric ependymoma. Similar to previous studies, GTR/NTR was the most important prognostic factor. Intervals up to 9 weeks from surgery to PRT did not compromise disease outcomes. There was no LC benefit between patients treated with >54 Gray relative biological effectiveness (GyRBE) versus ≤54 GyRBE.

Long-term health-related quality of life in pediatric brain tumor survivors receiving proton radiotherapy at <4 years of age.

BACKGROUND: The purpose of this analysis is to report long-term health-related quality of life (HRQoL) among brain tumor survivors treated with proton therapy (PRT) at a very young age. METHODS: Fifty-nine children <4 years old received PRT between 2000 and 2011. Forty families participated. HRQoL was assessed by child self-report (CSR; age ≥5) and parent proxy report (PPR; age 2+) using the PedsQL Core. RESULTS: The median age was 2.5 years (range, 0.3-3.8) at PRT and 9.1 years (5.5-18) at last follow-up. The most common diagnoses were ependymoma (n = 22) and medulloblastoma (n = 7). Median follow-up is 6.7 years (3-15.4). Follow-up mean CSR and PPR scores were: total core (78.4 and 72.9), physical (82.9 and 75.2), psychosocial (76.0 and 71.6), emotional (74.4 and 70.7), social (81.2 and 75.1), and school (72.4 and 69.9). Parent-reported HRQoL fell within a previously defined range for healthy children in 37.5% of patients, and for children with severe health conditions in 45% of patients. PPR HRQoL was stable from baseline to last follow-up among all domains except for social functioning. History of gastrostomy tube was significantly associated with poorer CSR and PPR HRQoL on multivariable analysis. Ninety percent of children functioned in a regular classroom, 14 (36%) used a classroom aid, 9 (23%) used an outside tutor, and 18 (46%) had an individualized education plan. CONCLUSION: Long-term HRQoL among brain tumor survivors treated with PRT at a very young age is variable, with over a third achieving HRQoL levels commensurate with healthy children. KEY POINTS: 1. One third of survivors reported long-term HRQoL scores comparable to those of healthy children.2. Treatment for hydrocephalus or a feeding tube was associated with significantly lower HRQoL.3. Total core HRQoL scores remained stable from baseline to last follow-up.

Giant Cell Lesions of the Maxillofacial Skeleton Express RANKL by RNA In Situ Hybridization Regardless of Histologic Pattern.

Maxillofacial central giant cell lesions (CGCLs) are often locally aggressive tumors in young patients that may be histologically very similar to or quite distinct when compared with giant cell tumors (GCTs) of long bones. It has been well established that GCTs express high levels of receptor activator of nuclear factor-kappa B ligand (RANKL) and are amenable to treatment with denosumab. To assess the predictive value of morphology, we evaluated CGCLs with GCT-like or non-GCT-like histology for RANKL expression by RNA in situ hybridization. Tumors were classified by clinical and radiographic criteria as aggressive or nonaggressive and histopathologically as resembling GCT or non-GCT-like. RNA in situ hybridization for RANKL mRNA was performed and scored semiquantitatively based on the magnification at which the signal was first detected. There were 17 patients (M:F=8:9) with a median age of 15 years. Nine patients were children under 18 years of age. In 10 patients, tumors were characterized as GCT-like and in 7, non-GCT-like; 6 occurred in the setting of a known associated syndrome. Of the sporadic tumors, 9/11 (82%) were classified as aggressive. Fifteen of 17 (88%) tumors strongly expressed RANKL (8/9 aggressive, 2/2 nonaggressive; 10/10 GCT-like and 5/7 non-GCT-like). Two patients with clinically aggressive CGCL, GCT-like histology and high tumor RANKL expression were identified as candidates for a trial of denosumab with notable clinical response. CGCLs demonstrate strong and diffuse RANKL mRNA expression in mononuclear stromal cells, regardless of histology or presence of an associated syndrome. Denosumab may be clinically beneficial in aggressive CGCLs.

Increased distance from a treating proton center is associated with diminished ability to follow patients enrolled on a multicenter radiation oncology registry.

PURPOSE: Consistent follow-up and data collection are necessary to identify long-term benefits/detriments of proton radiotherapy. Obtaining comprehensive clinical follow-up can be difficult and time-intensive for proton centers. Here we evaluate what factors affect maximum follow-up time among MGH Pediatric Proton Consortium Registry (PPCR) participants. PATIENTS AND METHODS: Enrollment in the PPCR was offered to any patient <22 years receiving protons. Patients were excluded from analysis if they were taken off study due to death or withdrawal. Distance from MGH was calculated by the great-circle formula. We utilized both univariate and multivariate analyses to determine risk factors associated with follow-up time. RESULTS: 333 PPCR patients enrolled between 10/2012 and 03/2017 were included. Median follow-up was 2.4 years (<1-5.5), and median distance away from the proton center was 256.4 km (<1.6-16,949.6). Distance from MGH significantly predicted follow-up time: patients living outside the Boston Metropolitan Statistical Area, >121 km from the proton center, had average follow-up that was 0.53 years less compared to those living within 121 km (p = 0.0002). Loss in average follow-up was also associated with Medicaid insurance, treatment delay due to insurance, and non-White race. Those co-enrolled on a proton trial or seen at a facility had significantly increased follow-up by almost one year (p < 0.0001). CONCLUSION: Patients living further from treating proton center have shorter follow-up durations. Increased distance from treating centers may adversely affect clinical outcomes research. Enhanced sharing of medical information among care providers and improved collection methods are needed to effectively evaluate the benefits of proton therapy.

Characteristics and Predictors for Secondary Leukemia and Myelodysplastic Syndrome in Ewing and Osteosarcoma Survivors.

PURPOSE: Long-term survivors of Ewing sarcoma (ES) and osteosarcoma may be at risk for therapy-related acute leukemia or myelodysplastic syndrome (t-AL/MDS). METHODS AND MATERIALS: We retrospectively reviewed the clinicopathologic characteristics of 1071 patients with osteosarcoma (n = 757) and ES (n = 314) who were treated between 1985 and 2014. Multivariable competing risk analysis was used to analyze predictors of t-AL/MDS, including a radiation dose (≥55.8 Gy vs <55.8 Gy) × disease site (pelvis/spine vs other) interaction term. A supplemental nested case-control study was conducted to assess the association between cumulative chemotherapy dose and t-AL/MDS. RESULTS: The median follow-up for surviving patients was 97 months (range, 0.03-380). Twenty patients developed t-AL/MDS, all of whom received chemotherapy and 15 of whom were treated with radiation therapy. Radiation therapy to ≥55.8 Gy was associated with development of t-AL/MDS (adjusted hazard ratio, 2.89; 95% confidence interval [CI], 1.23-6.80; P = .015), and there was a significant radiation dose × disease site interaction term (adjusted hazard ratio, 6.70; 95% CI, 2.71-16.53; Pinteraction < .001). The 5-year cumulative incidence of t-AL/MDS in patients receiving ≥55.8 Gy radiation therapy to the pelvis or spine was 5.0% (95% CI, 0.9-14.9) for osteosarcoma and 10.7% for ES (95% CI, 3.3-23.2). In our nested case-control study, cumulative doses of ifosfamide and etoposide were associated with development of t-AL/MDS. CONCLUSIONS: Patients with osteosarcoma and ES receiving ≥55.8 Gy of radiation therapy to the pelvis or spine appear to be at increased risk for t-AL/MDS. Treatment with high cumulative doses of chemotherapy may further augment this risk.

Effects of dexrazoxane on doxorubicin-related cardiotoxicity and second malignant neoplasms in children with osteosarcoma: a report from the Children's Oncology Group.

BACKGROUND: Dexrazoxane protects from lower-cumulative-dose doxorubicin cardiotoxicity, but the effect of dexrazoxane in children with sarcoma treated with higher-cumulative-dose doxorubicin is unknown. METHODS: We evaluated children with osteosarcoma (OS) on two Children's Oncology Group trials with higher dose doxorubicin (375-600 mg/m2) preceded by dexrazoxane (10:1 dexrazoxane:doxorubicin dosing). They were evaluated after the minimum expected treatment time (METT), defined as 28 weeks. Cardiotoxicity was identified by echocardiography and serum N-terminal pro-brain natriuretic peptide (NT-proBNP). Second malignant neoplasm (SMN) data was collected. RESULTS: All children had normal left ventricular (LV) systolic function as measured by LV fractional shortening and no heart failure. The end-diastolic septal thickness Z-scores (P < 0.01) and LV mass Z-scores (P < 0.01) were significantly smaller than normal for body-surface area in both sexes. The average LV mass Z-scores were significantly smaller for girls (P < 0.01) and marginally smaller for boys (P = 0.06). Girls had significantly smaller LV end-diastolic dimension Z-scores normalized to BSA (P < 0.01) compared to healthy controls and had significant increases in NT-proBNP. Four children developed SMNs as first events, a rate similar to historical controls. CONCLUSIONS: Dexrazoxane prevented LV dysfunction and heart failure in children with OS receiving higher dose doxorubicin. However, LV structural changes were not fully prevented, especially in girls. As a result, hearts become abnormally small for body size, resulting in higher LV stress. Dexrazoxane did not increase the risk of SMN. Dexrazoxane should be used in this population, particularly for girls, to mitigate anthracycline-induced cardiotoxicity. TRIAL REGISTRATIONS: ClinicalTrials.gov: NCT00003937 (P9754) registered 1 Nov 1999, and NCT00023998 (AOST0121) registered 13 Sept 2001.

Endocrine Deficiency As a Function of Radiation Dose to the Hypothalamus and Pituitary in Pediatric and Young Adult Patients With Brain Tumors.

PURPOSE: There are sparse data defining the dose response of radiation therapy (RT) to the hypothalamus and pituitary in pediatric and young adult patients with brain tumors. We examined the correlation between RT dose to these structures and development of endocrine dysfunction in this population. MATERIALS AND METHODS: Dosimetric and clinical data were collected from children and young adults (< 26 years of age) with brain tumors treated with proton RT on three prospective studies (2003 to 2016). Deficiencies of growth hormone (GH), thyroid hormone, adrenocorticotropic hormone, and gonadotropins were determined clinically and serologically. Incidence of deficiency was estimated using the Kaplan-Meier method. Multivariate models were constructed accounting for radiation dose and age. RESULTS: Of 222 patients in the study, 189 were evaluable by actuarial analysis, with a median follow-up of 4.4 years (range, 0.1 to 13.3 years), with 31 patients (14%) excluded from actuarial analysis for having baseline hormone deficiency and two patients (0.9%) because of lack of follow-up. One hundred thirty patients (68.8%) with medulloblastoma were treated with craniospinal irradiation (CSI) and boost; most of the remaining patients (n = 56) received involved field RT, most commonly for ependymoma (13.8%; n = 26) and low-grade glioma (7.4%; n = 14). The 4-year actuarial rate of any hormone deficiency, growth hormone, thyroid hormone, adrenocorticotropic hormone, and gonadotropin deficiencies were 48.8%, 37.4%, 20.5%, 6.9%, and 4.1%, respectively. Age at start of RT, time interval since treatment, and median dose to the combined hypothalamus and pituitary were correlated with increased incidence of deficiency. CONCLUSION: Median hypothalamic and pituitary radiation dose, younger age, and longer follow-up time were associated with increased rates of endocrinopathy in children and young adults treated with radiotherapy for brain tumors.

Quality of life in patients with proton-treated pediatric medulloblastoma: Results of a prospective assessment with 5-year follow-up.

BACKGROUND: To the authors' knowledge, health-related quality of life (HRQOL) outcomes are not well described in patients with medulloblastoma. The use of proton radiotherapy (RT) may translate into an improved HRQOL. In the current study, the authors report long-term HRQOL in patients with proton-treated pediatric medulloblastoma. METHODS: The current study was a prospective cohort HRQOL study of patients with medulloblastoma who were treated with proton RT and enrolled between August 5, 2002, and October 8, 2015. Both child report and parent-proxy report Pediatric Quality of Life Inventory (PedsQL) surveys were collected at baseline during RT and annually thereafter (score range on surveys of 0-100, with higher scores indicating better HRQOL). Patients were dichotomized by clinical/treatment variables and subgroups were compared. Mixed-model analysis was performed to determine the longitudinal trajectory of PedsQL scores. The Student t test was used to compare long-term HRQOL measures with published means from a healthy child population. RESULTS: Survey data were evaluable for 116 patients with a median follow-up of 5 years (range, 1-10.6 years); the median age at the time of diagnosis was 7.6 years (range, 2.1-18.1 years). At baseline, children reported a total core score (TCS) of 65.9, which increased by 1.8 points annually (P<.001); parents reported a TCS of 59.1, which increased by 2.0 points annually. Posterior fossa syndrome adversely affected baseline scores, but these scores significantly improved with time. At the time of last follow-up, children reported a TCS of 76.3, which was 3.3 points lower than that of healthy children (P = .09); parents reported a TCS of 69, which was 11.9 points lower than that of parents of healthy children (P<.001). Increased follow-up time from diagnosis correlated with improved HRQOL scores. CONCLUSIONS: HRQOL scores appear to increase over time after treatment in children treated with proton RT for medulloblastoma but remain lower compared with those of parent-proxy reports as well as published means from a healthy normative sample of children. Additional follow-up may translate into continued improvements in HRQOL. Cancer 2018. © 2018 American Cancer Society.

Left hippocampal dosimetry correlates with visual and verbal memory outcomes in survivors of pediatric brain tumors.

BACKGROUND: Radiotherapy (RT) in the pediatric brain tumor population causes late neurocognitive effects. In the current study, the authors investigated associations between clinical and dosimetric risk factors and memory outcomes in a cohort of patients treated with proton radiotherapy (PRT). METHODS: A total of 70 patients (median age at PRT, 12.1 years [range, 5.0-22.5 years]) who were treated with PRT were identified with baseline and follow-up evaluations of visual and verbal memory (Children's Memory Scale and the third edition of the Wechsler Memory Scale). Whole-brain as well as bilateral hippocampal and temporal lobe contours were delineated for the calculation of dosimetric indices. Multivariate analyses were performed to assess associations of score changes over time with clinical factors and dosimetric indices. RESULTS: The median neurocognitive follow-up was 3.0 years (range, 1.1-11.4 years). For the entire cohort, delayed and immediate verbal memory scaled scores demonstrated small declines. The mean decline for delayed verbal memory scores was 0.6 (P = .01), and that for immediate verbal memory scores was 0.5 (P = .06). Immediate and delayed visual memory scores were not found to change significantly (+0.1 and -0.3, respectively; P>.30). A higher left hippocampal V20GyE (percentage of the volume of a particular anatomical region receiving at least a 20 gray equivalent) was correlated with a score decline in all 4 measures. Female sex was found to be predictive of lower delayed verbal memory follow-up scores (P = .035). CONCLUSIONS: Only delayed verbal memory scores were found to have declined statistically significantly at follow-up after PRT, reflecting some weakness in verbal memory retrieval. Given a correlation of left hippocampal dosimetry and memory outcomes after PRT, left hippocampal-sparing PRT plans may assist patients with pediatric brain tumors in preserving memory-retrieval abilities. Cancer 2018;124:2238-45. © 2018 American Cancer Society.

Early clinical observations on the use of imatinib mesylate in FOP: A report of seven cases.

BACKGROUND: Fibrodysplasia ossificans progressiva (FOP) is an ultrarare genetic disorder of progressive, disabling heterotopic ossification (HO) for which there is presently no definitive treatment. Research studies have identified multiple potential targets for therapy in FOP, and novel drug candidates are being developed for testing in clinical trials. A complementary approach seeks to identify approved drugs that could be re-purposed for off-label use against defined targets in FOP. One such drug is imatinib mesylate, a tyrosine kinase inhibitor originally developed for use in patients with chronic myeloid leukemia (CML). Imatinib has the desirable effect of attacking multiple targets involved in the early hypoxic and inflammatory stages of FOP flare-ups, including HIF1-α, PDGFRα, c-KIT, and multiple MAP kinases. RESULTS: Based on compelling biologic rationale, strong preclinical data, and a favorable safety profile, imatinib has been prescribed on an off-label basis in a non-trial setting in seven children with continuous FOP flare-ups, predominantly in the axial regions, and which were not responsive to standard-of-care regimens. Anecdotal reports in these seven isolated cases document that the medication was well-tolerated with a ubiquitous reported decrease in the intensity of flare-ups in the six children who took the medication. CONCLUSIONS: These early clinical observations support the implementation of clinical trials in children with uncontrolled FOP flare-ups to determine if imatinib may ameliorate symptoms or alter the natural history of this debilitating and life-threatening disease.

Genetic Analysis of Giant Cell Lesions of the Maxillofacial and Axial/Appendicular Skeletons.

PURPOSE: To compare the genetic and protein expression of giant cell lesions (GCLs) of the maxillofacial (MF) and axial/appendicular (AA) skeletons. We hypothesized that when grouped according to biologic behavior and not simply by location, MF and AA GCLs would exhibit common genetic characteristics. MATERIALS AND METHODS: This was a prospective and retrospective study of patients with GCLs treated at Massachusetts General Hospital from 1993 to 2008. In a preliminary prospective study, fresh tissue from 6 aggressive tumors each from the MF and AA skeletons (n = 12 tumors) was obtained. RNA was extracted and amplified from giant cells (GCs) and stromal cells first separated by laser capture microdissection. Genes highly expressed by GCs and stroma at both locations were determined using an Affymetrix GeneChip analysis. As confirmation, a tissue microarray (TMA) was created retrospectively from representative tissue of preserved pathologic specimens to assess the protein expression of the commonly expressed genes found in the prospective study. Quantification of immunohistochemical staining of MF and AA lesions was performed using Aperio image analysis to determine whether immunoreactivity was predictive of aggressive or nonaggressive behavior. RESULTS: Five highly ranked genes were found commonly in GCs and stroma at each location: matrix metalloproteinase-9 (MMP-9), cathepsin K (CTSK), T-cell immune regulator-1 (TCIRG1), C-type lectin domain family-11, and zinc finger protein-836. MF (n = 40; 32 aggressive) and AA (n = 48; 28 aggressive) paraffin-embedded tumors were included in the TMA. The proteins CTSK, MMP-9, and TCIRG1 were confirmed to have abundant expression within both MF and AA lesions. Only the staining levels for TCIRG1 within the GCs predicted the clinical behavior of the MF lesions. CONCLUSIONS: MMP-9, CTSK, and TCIRG1 are commonly expressed by GCLs of the MF and AA skeletons. This supports the hypothesis that these lesions are similar but at different locations. TCIRG1 has not been previously associated with GCLs and could be a potential target for molecular diagnosis and/or therapy.