Late-onset lymphopenia during radiation is associated with an increased risk of tumor recurrence in newly diagnosed pediatric medulloblastoma.

BACKGROUND: Recent data found a correlation between lymphopenia occurring early during craniospinal radiation therapy (RT) and risk of disease recurrence in newly diagnosed childhood medulloblastoma. However, the population included patients who received chemotherapy prior to or during RT. Here, we investigate the effect of lymphopenia during RT in patients with newly diagnosed pediatric medulloblastoma who were chemotherapy-naïve. PROCEDURE: We analyzed 79 patients with newly diagnosed medulloblastoma (ages 2-21 years) treated between 1997 and 2013 with craniospinal RT. Log-rank tests were used to determine survival differences, and Cox proportional hazards regression was used to assess associations between patient characteristics and lymphopenia with disease recurrence risk. RESULTS: Eighty-three percent of patients (62/75) had grade ≥3 lymphopenia by RT Week 3, with 95% developing grade ≥3 lymphopenia at some point during therapy. There was no difference in incidence of lymphopenia between those who received proton beam RT (93%) versus photon (97%). Twenty-four of 79 (30%) patients developed disease recurrence at an average 27.0 months after diagnosis. There was higher risk of disease recurrence in patients with grade ≥3 lymphopenia during RT Week 4 (log-rank p = .016; Cox p = .03) and Week 5 (log-rank p = .024; Cox p = .032); after adjusting for clinical risk group, only grade ≥3 lymphopenia at Week 4 remained prognostic (Cox p = .04). No correlation was found between risk of tumor recurrence and early lymphopenia (RT Weeks 0-3) or absolute lymphocyte count (ALC) below the median at any time during RT. CONCLUSIONS: Lymphopenia during RT Weeks 4 and 5 correlates with increased risk of tumor recurrence in pediatric patients with newly diagnosed medulloblastoma.

Prognostic factors for pediatric, adolescent, and young adult patients with non-DIPG grade 4 gliomas: a contemporary pooled institutional experience.

PURPOSE: WHO grade 4 gliomas are rare in the pediatric and adolescent and young adult (AYA) population. We evaluated prognostic factors and outcomes in the pediatric versus AYA population. METHODS: This retrospective pooled study included patients less than 30 years old (yo) with grade 4 gliomas treated with modern surgery and radiotherapy. Overall survival (OS) and progression-free survival (PFS) were characterized using Kaplan-Meier and Cox regression analysis. RESULTS: Ninety-seven patients met criteria with median age 23.9 yo at diagnosis. Seventy-seven patients were ≥ 15 yo (79%) and 20 patients were < 15 yo (21%). Most had biopsy-proven glioblastoma (91%); the remainder had H3 K27M-altered diffuse midline glioma (DMG; 9%). All patients received surgery and radiotherapy. Median PFS and OS were 20.9 months and 79.4 months, respectively. Gross total resection (GTR) was associated with better PFS in multivariate analysis [HR 2.00 (1.01-3.62), p = 0.023]. Age ≥ 15 yo was associated with improved OS [HR 0.36 (0.16-0.81), p = 0.014] while female gender [HR 2.12 (1.08-4.16), p = 0.03] and DMG histology [HR 2.79 (1.11-7.02), p = 0.029] were associated with worse OS. Only 7% of patients experienced grade 2 toxicity. 62% of patients experienced tumor progression (28% local, 34% distant). Analysis of salvage treatment found that second surgery and systemic therapy significantly improved survival. CONCLUSION: Age is a significant prognostic factor in WHO grade 4 glioma, which may reflect age-related molecular alterations in the tumor. DMG was associated with worse OS than glioblastoma. Reoperation and systemic therapy significantly increased survival after disease progression. Prospective studies in this population are warranted.

The role of neoadjuvant chemotherapy in the management of metastatic central nervous system germinoma: A meta-analysis.

BACKGROUND: The role of neoadjuvant chemotherapy in treating patients with metastatic central nervous system (CNS) germinoma is controversial. METHODS: We compared the relapse-free survival (RFS) of different treatment modalities by performing a meta-analysis using published data. We summarized all data using standard descriptive statistics. We used the Kaplan-Meier method to estimate RFS and their corresponding 95% confidence intervals (CIs). We used the log-rank test for the comparison of survival functions. RESULTS: We identified 97 patients with a median age at presentation of 15 years (range: 7-38). Sites of metastasis were cerebrospinal fluid (CSF) disease only (n = 12), brain parenchyma (n = 18), spinal cord (n = 9), ventricular and CSF (n = 10), ventricular only (n = 31), and other (n = 17). The 3-year RFS among patients who received any form of radiotherapy was 89% (95% CI: 83-96) compared with 0% for patients who received a chemotherapy-only regimen (p = .001). Five-year RFS among patients who received craniospinal irradiation (CSI) was 92% (95% CI: 84-100) compared with 76.4% (95% CI: 63-90) in the non-CSI group (with or without neoadjuvant chemotherapy) (p = .014). Five-year RFS of patients who received CSI less than 24 Gy with neoadjuvant chemotherapy was 100% compared with 92% (95% CI: 83-100) CSI dose greater than or equal to 24 Gy alone (p = .3). CONCLUSIONS: Our analysis does not support avoiding spinal irradiation among patients with radiographic metastatic CNS germinoma. Future studies are needed to confirm whether neoadjuvant chemotherapy will allow a reduction of irradiation dose without compromising survival.

Renal function in abdominal neuroblastoma patients undergoing proton radiotherapy.

BACKGROUND: The purpose of this study is to analyze renal function outcomes in abdominal neuroblastoma patients undergoing proton therapy (PT). PROCEDURE: From 2011 to 2019, two single-institution Institutional Review Board-approved protocols prospectively enrolled neuroblastoma patients for data collection. To assess renal function, serum creatinine (Cr), blood urea nitrogen (BUN), and creatinine clearance (CrCl) before proton therapy (pre-PT) were compared with the values at last follow-up. RESULTS: A total of 30 children with abdominal neuroblastoma with median age 3.5 years (range, 0.9-9.1) at time of PT were included in this study. All patients underwent chemotherapy and resection of primary tumor prior to PT. Two patients required radical nephrectomy. Median follow-up after PT was 35 months. Mean dose to ipsilateral and contralateral kidney was 13.9 and 5.4 Gy, respectively. No patients developed hypertension or renal dysfunction during follow-up. There was no statistically significant change in serum BUN (p = .508), CrCl (p = .280), or eGFR (p = .246) between pre-PT and last follow-up. CONCLUSION: At a median follow-up of almost 3 years, renal toxicity was uncommon after PT. Longer follow-up and larger patient cohort data are needed to further assess impact of PT on renal function in this population.

Contrast Enhancement Patterns in Pediatric Glioblastomas.

BACKGROUND AND PURPOSE: Brain tumors are the most common cause of cancer-related deaths among the pediatric population. Among these, pediatric glioblastomas (GBMs) comprise 2.9% of all central nervous system tumors and have a poor prognosis. The purpose of this study is to determine whether the imaging findings can be a prognostic factor for survival in children with GBMs. MATERIALS AND METHODS: The imaging studies and clinical data from 64 pediatric patients with pathology-proven GBMs were evaluated. Contrast enhancement patterns were classified into focal, ring-like, and diffuse, based on preoperative postcontrast T1-weighted magnetic resonance images. We used the Kaplan-Meier method and Cox proportional hazard regression to evaluate the prognostic value of imaging findings. RESULTS: Patients with ring-enhanced GBMs who underwent gross total resection or subtotal resection were found to have a significantly shorter progression-free survival ( P = 0.03) comparing with other enhancing and nonenhancing glioblastomas. CONCLUSIONS: In this study, we analyzed survival factors in children with pediatric glioblastomas. In the group of patients who underwent gross total resection or subtotal resection, those patients with focal-enhanced GBMs had significantly longer progression-free survival ( P = 0.03) than did those with other types of enhancing GBMs (diffuse and ring-like).

Overall survival and secondary malignant neoplasms in children receiving passively scattered proton or photon craniospinal irradiation for medulloblastoma.

BACKGROUND: Both intensity-modulated radiotherapy (RT) and passively scattered proton therapy have a risk of secondary malignant neoplasm (SMN) in children. To determine the influence of RT modality on the incidence of SMN after craniospinal irradiation (CSI), the authors compared the incidence of SMN in children who had medulloblastoma treated with either photon CSI plus an intensity-modulated RT boost (group I) or passively scattered proton CSI plus a boost (group II). METHODS: From 1996 to 2014, 115 children with medulloblastoma (group I, n = 63; group II, n = 52) received CSI followed by a boost to the tumor bed. Most patients had standard-risk disease (63.5%). The median follow-up was 12.8 years for group I and 8.7 years for group II. RESULTS: The 5-year and 10-year overall survival (OS) rates were 88.8% and 85.1%, respectively, for standard-risk patients and 63.1% and 57.3%, respectively, for high-risk patients, with no OS difference by RT modality (P = .81). Six SMNs were identified (4 in group I, 2 in group II). The 5-year and 10-year SMN incidence rates were 1.0% and 6.9%, respectively (0.0% and 8.0%, respectively, in group I; 2.2% and 4.9%, respectively, in group II; P = .74). Two SMNs occurred in the clinical target volume in the brain, 2 occurred in the exit dose region from the photon spinal field, 1 occurred in the entrance path of a proton beam, and 1 occurred outside the radiation field. There were no reported cases of secondary leukemia. CONCLUSIONS: This analysis demonstrates no difference in OS or SMN incidence between patients in groups I and II 10 years after RT. LAY SUMMARY: One hundred fifteen children with medulloblastoma received radiotherapy (RT) with either photon craniospinal irradiation (CSI) and an intensity-modulated RT boost (group I; n = 63) or passively scattered proton CSI and a boost (group II;, n = 52). The majority of children had standard-risk disease (63.5%). The 5-year and 10-year overall survival rates were 88.8% and 85.1% for standard-risk patients, respectively, and 63.1% and 57.3% for high-risk patients, respectively, with no difference in overall survival by RT group (P = .81). The 5-year and 10-year second malignant neoplasm incidence rates were 1.0% and 6.9%, respectively, with no difference in second malignant neoplasm incidence according to RT group (P = .74).

Observed-to-expected incidence ratios of second malignant neoplasms after radiation therapy for medulloblastoma: A Surveillance, Epidemiology, and End Results analysis.

BACKGROUND: The authors analyzed the incidence and types of second malignant neoplasms (SMNs) in patients treated for medulloblastoma. METHODS: The authors compared the incidence of SMNs after radiotherapy (RT) for medulloblastoma in patients treated in 1973-2014 with the incidence in the general population with the multiple primary-standardized incidence ratio function of Surveillance, Epidemiology, and End Results 9. Observed-to-expected incidence (O/E) ratios and 95% confidence intervals (CIs) were reported for the entire cohort and by disease site according to age at diagnosis, treatment era, and receipt of chemotherapy. P values < .05 were considered statistically significant. RESULTS: Of the 1294 patients with medulloblastoma who received RT, 68 developed 75 SMNs. The O/E ratio for SMNs among all patients was 4.49 (95% CI, 3.53-5.62; P < .05). The site at highest risk was the central nervous system (CNS; O/E, 40.62; 95% CI, 25.46-61.51), which was followed by the endocrine system (O/E, 15.95; 95% CI, 9.12-25.91), bone (O/E, 14.45; 95% CI, 1.75-52.21), soft tissues (O/E, 9.01; 95% CI, 1.09-32.56), the digestive system (O/E, 5.03; 95% CI, 2.51-9.00), and the lymphatic/hematopoietic system (O/E, 3.37; 95% CI, 1.35-6.94). The O/E ratio was higher for patients given chemotherapy and RT (O/E, 5.52; 95% CI, 3.75-7.83) than for those given RT only (O/E, 3.96; 95% CI, 2.88-5.32). CONCLUSIONS: Patients with medulloblastoma are at elevated risk for SMNs in comparison with the general population. Variations in O/E for SMNs by organ systems were found for treatment modality, age at diagnosis, and time of diagnosis. The most common site, the CNS, was involved more often in younger patients and those given chemotherapy with RT.

Early radiotherapy preserves vision in sporadic optic pathway glioma.

BACKGROUND: Sporadic optic pathway/hypothalamic gliomas represent a unique entity within pediatric low-grade glioma. Despite favorable survival, location makes treatment difficult and local progression debilitating. This study is a longitudinal assessment of visual acuity (VA) among children treated within the last 2 decades. METHODS: Clinical characteristics were abstracted for patients treated from 2000 to 2018 at Texas Children's Cancer Center in Houston. Ophthalmologic data taken at 3- to 6-month intervals were examined with age-appropriate VA metrics converted to the LogMAR (logarithm of the minimum angle of resolution) scale. Kaplan-Meier blindness-free survival (BFS) curves, calculated as time-to-bilateral functional blindness (LogMAR ≥0.8 in both eyes), were calculated for patients receiving early radiation therapy (RT; upfront or as first-line salvage treatment) or chemotherapy (CT) and evaluated using the log-rank test. RESULTS: Thirty-eight patients with a median follow-up of 8.5 years (range, 2-17 years) were identified. Median age at diagnosis was 3 years (interquartile range, <1-6 years). Early RT was administered in 11 patients (29%). Twenty-seven patients (71%) were treated primarily with CT, initiated at a median age of 3.5 years (range, <1-11 years). Eight patients in the CT group did eventually require RT secondary to VA loss and following multiple lines of CT. Median age at RT for all patients was 11 years (range, 3-17 years). BFS rates were 81% at 5 years and 60% at 8 years for CT and 100% at 5 and 8 years for early RT (P = .017). CONCLUSIONS: In a contemporary cohort, early RT, defined as initial or first-line salvage therapy, was found to have superior BFS for appropriately selected patients with sporadic optic pathway/hypothalamic gliomas. LAY SUMMARY: Children with low-grade brain tumors of the optic pathway generally have excellent long-term survival; however, given the location of these tumors, there can commonly be threatened vision if the tumor grows. Although radiation is generally deferred in children on the basis of legitimate concerns regarding the effects on the developing brain, it may represent a vision-preserving therapy for well-selected older patients.

The role of radiation therapy in the management of cutaneous malignancies. Part I: Diagnostic modalities and applications.

Radiation therapy offers distinct advantages over other currently available treatments for cutaneous malignancies in certain circumstances. Dermatologists and dermatologic surgeons should be familiar with the available radiation therapy techniques as well as their value and potential limitations in a variety of clinical scenarios. The first article in this 2-part continuing medical education series highlights the mechanisms, modalities, and applications of the most commonly used radiotherapy treatments as they relate to cutaneous oncology. We review the current indications for the use of radiation in the treatment of various cutaneous malignancies, the techniques commonly employed in modern radiotherapy, and the associated complications.

The role of radiation therapy in the management of cutaneous malignancies. Part II: When is radiation therapy indicated?

Radiation therapy may be performed for a variety of cutaneous malignancies, depending on patient health status, tumor clinical and histologic features, patient preference, and resource availability. Dermatologists should be able to recognize the clinical scenarios in which radiation therapy is appropriate, as this may reduce morbidity, decrease risk of disease recurrence, and improve quality of life. The second article in this 2-part continuing medical education series focuses on the most common indications for radiation therapy in the treatment of basal cell carcinoma, cutaneous squamous cell carcinoma, dermatofibrosarcoma protuberans, Merkel cell carcinoma, Kaposi sarcoma, angiosarcoma, cutaneous lymphoma, melanoma, undifferentiated pleomorphic sarcoma, and sebaceous carcinoma.

Development of second primary tumors and outcomes in medulloblastoma by treatment modality: A Surveillance, Epidemiology, and End Results analysis.

BACKGROUND: As treatment modalities for medulloblastoma have developed and overall survival (OS) has improved, there are relatively limited data on the impact of long-term effects such as risk of second primary tumors (SPT). To address the knowledge gap, we analyzed factors associated with the risk of SPT and OS by treatment modality for medulloblastoma. METHODS: We queried the Surveillance, Epidemiology, and End Results (SEER)-18 database for patients diagnosed with medulloblastoma in 1973-2014. Patients were then grouped by age, gender, race, geographic region, histology, adjuvant treatment (no radiation [RT] and no chemotherapy [CT], RT and CT, RT alone, or CT alone), era of diagnosis (1973-1994 or 1995-2014), and survival time. Cumulative incidence, factors associated with SPT and OS were analyzed. RESULTS: Of 2271 patients, 146 developed SPT, of which 42 were benign. The incidence of SPT was 3.1% and 4.9% at 10 and 15 years, respectively. The incidence of SPT was 3.1% with RT + CT versus 3.7% with RT alone at 10 years. The most common site for an SPT was the central nervous system. Female gender (P = 0.01) and longer OS of ≥21 years (P < 0.01) were associated with higher risk of SPT. RT + CT led to better OS than RT only (66.1% and 61.4% vs 55.6% and 49.7% at 10 and 15 years) (P < 0.01). CONCLUSIONS: Medulloblastoma patients have a relatively low risk of SPT at 10 years with treatment. Use of RT + CT led to better OS with no statistical difference in SPT compared with the RT alone.

Patterns of failure and toxicity profile following proton beam therapy for pediatric bladder and prostate rhabdomyosarcoma.

PURPOSE/OBJECTIVE(S): Bladder and prostate are unfavorable sites for rhabdomyosarcoma (B/P-RMS), and represent a challenging location for radiotherapy. MATERIALS/METHODS: Nineteen patients with B/P-RMS were enrolled on a prospective registry protocol (2008-2017) and treated with chemotherapy, proton beam therapy (PBT), and surgical resection (n = 8; 42%). Emphasis was given to treatment technique, disease-related outcomes, and toxicity associated with PBT. RESULTS: The majority of patients had bladder RMS (74%) of embryonal histology (95%), Group III (68%), and intermediate-risk disease by Children's Oncology Group (COG) risk stratification (89%). Seven patients (37%) had primary tumors >5 cm in size. All patients were treated according to COG protocols. With a median follow-up of 66.2 months, 5-year overall survival (OS) and progression-free survival (PFS) were 76%. Four patients (21%) experienced disease relapse, all presenting with local failure. The 5-year local control (LC) rate was 76%. Tumor size predicted LC, with 5-year LC for patients with >5 cm tumors being 43% versus 100% for those with ≤5 cm tumors (P = .006). Univariate analysis demonstrated an effect of tumor size on OS (tumor >5 cm, hazard ratio [HR] 17.7, P = .049) and PFS (HR 17.7, P = .049). Acute grade 2 toxicity was observed in two patients (11%, transient proctitis). Late grade 2+ toxicity was observed in three patients (16%; n = 1 grade 2 skeletal deformity; n = 3 transient grade 2 urinary incontinence; one patient experienced both). CONCLUSIONS: PBT for B/P-RMS affords promising disease-related outcomes with an acceptable toxicity profile. Higher local failure rates were observed for larger tumors, supporting dose-escalation components of ongoing RMS clinical trials.

Efficacy of proton therapy in children with high-risk and locally recurrent neuroblastoma.

PURPOSE: Proton therapy is currently used in the management of pediatric tumors to decrease late toxicities. However, one of the criticisms of proton therapy is the limited data regarding efficacy on disease control. The purpose of this study was to examine local and distant control rates after proton therapy for neuroblastoma. METHODS AND MATERIALS: Eighteen patients with high-risk (n = 16) and locally recurrent neuroblastoma (n = 2) were treated with curative intent and received proton therapy to the primary site and up to three post-induction MIBG-avid metastatic sites. Primary sites (n = 18) were treated to 21-36 Gy (relative biological effectiveness [RBE]), and metastatic sites (n = 16) were treated to 21-24 Gy (RBE). Local control and survival rates were calculated using the Kaplan-Meier method. RESULTS: With a median follow-up of 60.2 months, two- and five-year local control rates at the irradiated primary site were 94% and 87%, respectively. No failures at irradiated distant metastatic sites were observed. The five-year progression-free survival (PFS) was 64%, and the five-year overall survival (OS) was 94%. The extent of surgical resection was not associated with local control, PFS, or OS. No radiation-related nephropathy or hepatopathy was reported. CONCLUSIONS: Excellent local control was achieved using proton therapy to the primary and post-induction MIBG-positive distant sites. The predominant site of failure is progression in post-induction non-MIBG-avid distant sites. Although proton therapy provides high rates of local control with acceptable toxicity for neuroblastoma, further advances in systemic therapy are needed for the improved control of systemic disease.

Correction to: A predictive model for distinguishing radiation necrosis from tumour progression after gamma knife radiosurgery based on radiomic features from MR images.

The original version of this article, published on 24 November 2017, unfortunately contained a mistake.

A predictive model for distinguishing radiation necrosis from tumour progression after gamma knife radiosurgery based on radiomic features from MR images.

OBJECTIVES: To develop a model using radiomic features extracted from MR images to distinguish radiation necrosis from tumour progression in brain metastases after Gamma Knife radiosurgery. METHODS: We retrospectively identified 87 patients with pathologically confirmed necrosis (24 lesions) or progression (73 lesions) and calculated 285 radiomic features from four MR sequences (T1, T1 post-contrast, T2, and fluid-attenuated inversion recovery) obtained at two follow-up time points per lesion per patient. Reproducibility of each feature between the two time points was calculated within each group to identify a subset of features with distinct reproducible values between two groups. Changes in radiomic features from one time point to the next (delta radiomics) were used to build a model to classify necrosis and progression lesions. RESULTS: A combination of five radiomic features from both T1 post-contrast and T2 MR images were found to be useful in distinguishing necrosis from progression lesions. Delta radiomic features with a RUSBoost ensemble classifier had an overall predictive accuracy of 73.2% and an area under the curve value of 0.73 in leave-one-out cross-validation. CONCLUSIONS: Delta radiomic features extracted from MR images have potential for distinguishing radiation necrosis from tumour progression after radiosurgery for brain metastases. KEY POINTS: • Some radiomic features showed better reproducibility for progressive lesions than necrotic ones • Delta radiomic features can help to distinguish radiation necrosis from tumour progression • Delta radiomic features had better predictive value than did traditional radiomic features.

ACTION: a randomized phase 3 study of ONC201 (dordaviprone) in patients with newly diagnosed H3 K27M-mutant diffuse glioma.

BACKGROUND: H3 K27M-mutant diffuse glioma primarily affects children and young adults, is associated with a poor prognosis, and no effective systemic therapy is currently available. ONC201 (dordaviprone) has previously demonstrated efficacy in patients with recurrent disease. This phase 3 trial evaluates ONC201 in patients with newly diagnosed H3 K27M-mutant glioma. METHODS: ACTION (NCT05580562) is a randomized, double-blind, placebo-controlled, parallel-group, international phase 3 study of ONC201 in newly diagnosed H3 K27M-mutant diffuse glioma. Patients who have completed standard frontline radiotherapy are randomized 1:1:1 to receive placebo, once-weekly dordaviprone, or twice-weekly dordaviprone on 2 consecutive days. Primary efficacy endpoints are overall survival (OS) and progression-free survival (PFS); PFS is assessed by response assessment in neuro-oncology high-grade glioma criteria (RANO-HGG) by blind independent central review. Secondary objectives include safety, additional efficacy endpoints, clinical benefit, and quality of life. Eligible patients have histologically confirmed H3 K27M-mutant diffuse glioma, a Karnofsky/Lansky performance status ≥70, and completed first-line radiotherapy. Eligibility is not restricted by age; however, patients must be ≥10 kg at time of randomization. Patients with a primary spinal tumor, diffuse intrinsic pontine glioma, leptomeningeal disease, or cerebrospinal fluid dissemination are not eligible. ACTION is currently enrolling in multiple international sites.

Comprehensive radiotherapy for pediatric Ewing Sarcoma: Outcomes of a prospective proton study.

BACKGROUND AND PURPOSE: Patients with Ewing Sarcoma (EWS) are treated with multimodality therapy which includes radiation therapy (RT) as an option for local control. We report on the efficacy after proton radiation therapy (PRT) to the primary site for localized and metastatic EWS. MATERIALS AND METHODS: Forty-two children with EWS (33 localized, 9 metastatic) treated between 2007 and 2020 were enrolled on 2 prospective registry protocols for pediatric patients undergoing PRT. PRT was delivered by passive scatter (74 %), pencil-beam scanning (12 %) or mixed technique (14 %). Treated sites included the spine (45 %), pelvis/sacrum (26 %), skull/cranium (14 %), extraosseous (10 %), and chest wall (5 %). Median radiation dose was 54 Gy-RBE (range 39.6-55.8 Gy-RBE). Patients with metastatic disease received consolidative RT to metastatic sites (4 at the time of PRT to the primary site, 5 after completion of chemotherapy). Median follow-up time was 47 months after PRT. RESULTS: The 4-year local control (LC), progression-free survival (PFS), and overall survival (OS) rates were 83 %, 71 %, and 86 %, respectively. All local failures (n = 6) were in-field failures. Tumor size ≥ 8 cm predicted for inferior 4-year LC (69 % vs 95 %, p = 0.04). 4-year PFS and OS rates were not statistically different in patients with localized versus metastatic disease (72 % vs 67 %, p = 0.70; 89 % vs 78 %, p = 0.38, respectively). CONCLUSION: In conclusion, LC for pediatric patients with EWS treated with PRT was comparable to that of historical patients who received photon-RT. Tumor size ≥ 8 cm predicted increased risk of local failure. Patients with metastatic disease, including non-pulmonary only metastases, received radiation therapy to all metastatic sites and had favorable survival outcomes.

The cochlear dose and the age at radiotherapy predict severe hearing loss after passive scattering proton therapy and cisplatin in children with medulloblastoma.

BACKGROUND: Hearing loss (HL) is associated with worse neurocognitive outcomes among patients with medulloblastoma. We aimed to identify risk factors associated with severe HL and to evaluate the generalizability of a published HL calculator among patients treated with passive scattering proton therapy (PSPT) and cisplatin. METHODS: We identified patients aged 3-21 years who were treated at our centers between 2007-2022. Audiograms were graded using the International Society of Pediatric Oncology-Boston scale. Time to grade 3-4 HL was evaluated using Kaplan-Meier and multivariable Cox models to estimate hazard ratios (HR) and 95% confidence intervals (CI). RESULTS: Seventy-nine patients were treated with PSPT at a median age of 7.5 years (range:3.1-21.1). The mean cochlear dose (Dmc) (±S.D.) was 31.5±8.5 Gy, and the cumulative cisplatin dose was 295±50 mg/m2. Fifty-nine patients (75%) received amifostine. Patients completed a median of 9 audiograms (range:4-22) with a median audiogram follow-up of 49 months (range:6-177). Twenty-seven patients (34%) had grade 3-4 HL. In adjusted Cox models, only higher Dmc (HR=1.12, 95% CI:1.06-1.18) was associated with grade 3-4 HL. The predicted 3-year incidence of grade 3-4 HL was 40.0% (95% CI: 21.3-66.3) and 66.7% (95% CI: 35.4-93.7) for children with Dmc ≥36 Gy and age at radiotherapy ≥7 and <7 years, respectively (p=0.042). It was 8.9% (95% CI: 2.3-31.6) and 15.6% (95% CI: 5.3-41.1) for children with Dmc <36 Gy and age at radiotherapy ≥7 and <7 years, respectively (p=0.78). CONCLUSIONS: Children <7 years at radiotherapy with a Dmc ≥36 Gy are at higher risk for HL.

Salvage Stereotactic Radiosurgery for Recurrent WHO Grade 2 and 3 Meningiomas: A Multicenter Study (STORM).

PURPOSE: The role of stereotactic radiosurgery (SRS) in the management of grade 2 and 3 meningiomas is not well elucidated. Unfortunately, local recurrence rates are high, and guidelines for management of recurrent disease are lacking. To address this knowledge gap, we conducted STORM (Salvage Stereotactic Radiosurgery for Recurrent WHO Grade 2 and 3 Meningiomas), a multicenter retrospective cohort study of patients treated with primary SRS for recurrent grade 2 and 3 meningiomas. METHODS AND MATERIALS: Data on patients with recurrent grade 2 and 3 meningioma treated with SRS at first recurrence were retrospectively collected from 8 academic centers in the United States. Patients with multiple lesions at the time of initial diagnosis or more than 2 lesions at the time of first recurrence were excluded from this analysis. Patient demographics and treatment parameters were extracted at time of diagnosis, first recurrence, and second recurrence. Oncologic outcomes, including progression-free survival (PFS) and overall survival, as well as toxicity outcomes, were reported at the patient level. RESULTS: From 2000 to 2022, 108 patients were identified (94% grade 2, 6.0% grade 3). A total of 106 patients (98%) had upfront surgical resection (60% gross-total resection) with 18% receiving adjuvant radiation therapy (RT). Median time to first progression was 2.5 years (IQR, 1.34-4.30). At first recurrence, patients were treated with single or fractionated SRS to a median marginal dose of 16 Gy to a maximum of 2 lesions (87% received single-fraction SRS). The median follow-up time after SRS was 2.6 years. The 1-, 2-, and 3-year PFS was 90%, 75%, and 57%, respectively, after treatment with SRS. The 1-, 2-, and 3-year overall survival was 97%, 94%, and 92%, respectively. In the multivariable analysis, grade 3 disease (HR, 6.80; 95% CI, 1.61-28.6), male gender (HR, 3.48; 95% CI, 1.47-8.26), and receipt of prior RT (HR, 2.69; 95% CI, 1.23-5.86) were associated with worse PFS. SRS dose and tumor volume were not correlated with progression. Treatment was well tolerated, with a 3.0% incidence of grade 2+ radiation necrosis. CONCLUSIONS: This is the largest multicenter study to evaluate salvage SRS in recurrent grade 2 and 3 meningiomas. In this select cohort of patients with primarily grade 2 meningioma with a potentially more favorable natural history of delayed, localized first recurrence amenable to salvage SRS, local control rates and toxicity profiles were favorable, warranting further prospective validation.

Outcomes and Pattern of Care for Spinal Myxopapillary Ependymoma in the Modern Era-A Population-Based Observational Study.

(1) Background: Myxopapillary ependymoma (MPE) is a rare tumor of the spine, typically slow-growing and low-grade. Optimal management strategies remain unclear due to limited evidence given the low incidence of the disease. (2) Methods: We analyzed data from 1197 patients with spinal MPE from the Surveillance, Epidemiology, and End Results (SEER) database (2000-2020). Patient demographics, treatment modalities, and survival outcomes were examined using statistical analyses. (3) Results: Most patients were White (89.9%) with a median age at diagnosis of 42 years. Surgical resection was performed in 95% of cases. The estimated 10-year overall survival was 91.4%. Younger age (hazard ratio (HR) = 1.09, p < 0.001) and receipt of surgery (HR = 0.43, p = 0.007) were associated with improved survival. Surprisingly, male sex was associated with worse survival (HR = 1.86, p = 0.008) and a younger age at diagnosis compared to females. (4) Conclusions: This study, the largest of its kind, underscores the importance of surgical resection in managing spinal MPE. The unexpected association between male sex and worse survival warrants further investigation into potential sex-specific pathophysiological factors influencing prognosis. Despite limitations, our findings contribute valuable insights for guiding clinical management strategies for spinal MPE.