Pediatric Intracranial Arteriovenous Malformation: Long-Term Outcomes with Linear Accelerator (LINAC)-Based Radiosurgery.

PURPOSE: To analyze and report the long-term outcomes of intracranial arteriovenous malformations (AVM) treated with linear accelerator (LINAC)-based radiosurgery (LBRS) in the pediatric population. METHODS AND MATERIALS: A series of 34 pediatric patients (≤18 years old) who were treated between 2002 and 2016 were analyzed. All patients were treated with LBRS in a single fraction, with a median dose of 16.8 Gy to the 80% isodose line. Median age at treatment was 14.4 years (range 5.5-18.9). Median AVM volume was 2.91 mL (range 0.228-27.313). Median modified radiosurgery-based AVM score was 0.83 (range 0.18-2.96). The most common presenting symptom was intracranial hemorrhage (ICH) (n = 22, 64.7%). Nine patients underwent intervention before LBRS, which included prior embolization or resection. Seven lesions were in eloquent locations, defined as basal ganglia, thalamus, or brainstem. Cerebral angiography was done to confirm obliteration. RESULTS: Median follow-up time was 98 months (range 36-200 months). Twenty-two of the 34 lesions were obliterated (64.7%) with median time to obliteration of 37 months (range 14-79). No deaths occurred during the follow up period; however, two patients experienced ICH after treatment. Three other patients were treated for symptomatic radiation necrosis. CONCLUSIONS: Treatment of intracranial AVM with LBRS in the pediatric population is demonstrated to be safe and effective with long-term follow up.

A comparative outcomes analysis of patients treated for arteriovenous malformation with LINAC-based stereotactic radiosurgery by a standard frame-based technique or a frameless technique utilizing 3-dimensional rotational angiography.

Previous work at our institution treating arteriovenous malformation (AVM) with radiosurgery (RS) demonstrated superior nidus visualization and geometric accuracy with use of 3-dimensional rotational angiography (3DRA) compared to biplanar digital subtraction angiography. We have since adopted a unique radiosurgical protocol that utilizes 3DRA in the planning of linear accelerator (LINAC)-based RS delivered in a frameless manner. This study seeks to compare clinical outcomes between patients treated by this novel approach and those treated by our historic frame-based protocol. Clinical data were queried for all patients treated for AVM by single-fraction RS from 2003 to 2017. RICs were identified and classified as radiologic, symptomatic, or permanent. Excellent outcome was defined as nidus obliteration without intracranial hemorrhage (ICH) or symptomatic RIC. Clinical predictors of study outcomes were identified through univariate and multivariate logistic regression using backwards elimination to optimize a predictive model. 131 AVMs in 124 patients were included with a median follow-up of 88 months. 59 AVMs received frame-based RS and 72 AVMs received frameless RS. Rate of obliteration was 64% for frame-based RS and 61% for frameless RS (p = 0.70). Radiologic, symptomatic, and permanent RICs rates were 68%, 17%, and 8%, respectively, for frame-based cases, versus 40% (p < 0.01), 8% (p = 0.13), and 3% (p = 0.15), respectively, for frameless cases. Excellent outcome was achieved in 49% of frame-based cases and 53% of frameless cases (p = 0.68). These results illustrate the safety and effectiveness of frameless LINAC-based AVM RS utilizing 3DRA.

Long-Term Outcomes of Newly Diagnosed Resected Atypical Meningiomas and the Role of Adjuvant Radiotherapy.

OBJECTIVE: The role of adjuvant radiotherapy (ART) in patients with World Health Organization Grade II atypical meningiomas (AMs) remains controversial. METHODS: We retrospectively reviewed 149 patients with newly diagnosed resected AMs from 2000 to 2012. Gross total resection (GTR) was defined as Simpson Grades I-III and subtotal resection (STR) as Grades IV and V. Kaplan-Meier analyses of local control (LC), progression-free survival (PFS), and overall survival were performed with the log-rank test, and risk factors for progression/recurrence (P/R) were analyzed with multivariate Cox regression. RESULTS: Median follow-up was 74.2 months. GTR was achieved in 98 patients and STR in 51 patients. Fifty-three (35%) patients received ART. Overall, 46 patients (31%) experienced P/R with a median time to P/R of 32.4 months. ART was associated with a trend toward improved PFS (P = 0.0669) in the GTR subset but significantly improved LC (P = 0.0183) and PFS (P = 0.0034) in the STR subset. Age, tumor size, and STR were significant risk factors for worse PFS, whereas receiving ART was associated with improved PFS on multivariate analyses. Thirty-nine of the 46 progressive/recurrent patients underwent salvage therapy with only 22 patients experiencing long-term control. Five patients experienced transformation to World Health Organization Grade III malignant meningioma. CONCLUSIONS: Patients who undergo STR for newly diagnosed AM should receive ART based on improvements in LC and PFS. GTR patients should be considered for ART, but active surveillance is a reasonable management approach with the recognition that progressive/recurrent disease can act aggressively. Prospective, randomized trials are currently underway to evaluate the role of ART.

Integral Whole Brain Dose from Stereotactic Radiosurgery of 47 Metastatic Lesions: A Dosimetric Case Study.

This report describes the case of a 15-year-old male diagnosed with primary ALK-positive adenocarcinoma of the lung metastatic to the brain. He was treated with surgical resection for a single lesion followed by whole brain radiotherapy and subsequently underwent 10 courses of stereotactic radiosurgery for 47 lesions delivered over a four-year period. Currently, all metastatic lesions in the brain are completely resolved or locally controlled.

A comparative study of stereotactic radiosurgery, hypofractionated, and fractionated stereotactic radiotherapy in the treatment of skull base meningioma.

OBJECTIVES: To compare the outcomes of skull base meningiomas treated with stereotactic radiosurgery (SRS), hypofractionated stereotactic radiotherapy (hFSRT), and fractionated stereotactic radiotherapy (FSRT). METHODS: A total of 220 basal meningiomas in 213 patients were treated using SRS (N=55), hFSRT (N=22), and FSRT (N=143). The median age was 59 years (28 to 84 y). Prior surgery was performed in 74 cases; 39 patients received adjuvant radiotherapy after incomplete resection and 35 patients received salvage radiotherapy after tumor progression. In 146 cases, radiation was the primary therapy. Ten patients had World Health Organization II or III meningiomas. RESULTS: The median follow-up was 32 months (7 to 97 mo). Median tumor volume was 2.8 cm (0.10 to 16.94 cm), 4.8 cm (0.88 to 20.38 cm), and 11.1 cm (0.43 to 214.00 cm) and the median dose was 1250 cGy in 1 fraction to the 80% isodose line (IDL), 2500 cGy in 5 fractions to the 90% IDL, and 5040 cGy in 28 fractions to the 90% IDL for the SRS, hFSRT, and FSRT groups, respectively. Radiographic control was achieved in 91%, 94%, and 95% (P=0.25), whereas clinical response was seen in 89%, 100%, and 91% (P=0.16) in the SRS, hFSRT, and FSRT groups, respectively. CONCLUSIONS: There is no significant difference in the radiographic and clinical response in patients with skull base meningioma treated with SRS, hFSRT, or FSRT and thus gives the clinician the impetus to tailor treatment techniques to the location and size of the tumor at presentation.

Observation versus adjuvant radiation or chemotherapy in the management of stage I seminoma: clinical outcomes and prognostic factors for relapse in a large US cohort.

PURPOSE: The management of stage I seminoma has evolved over the past 20 years. Contemporary management options after orchiectomy include adjuvant radiation, adjuvant chemotherapy, and observation. This analysis defines the experience at Kaiser Permanente Southern California from 1990 to 2010. We examined outcomes for stage I seminoma patients and reviewed prognostic factors for recurrence in those managed with observation. MATERIALS AND METHODS: This is a retrospective study of 502 stage I seminoma patients who underwent orchiectomy from 1990 to 2010. Outcomes examined were relapse-free survival (RFS), overall survival (OS), and cause-specific survival (CSS). Risk factors for recurrence evaluated were age, preoperative hCG elevation, preoperative LDH elevation, tumor size, lymphovascular invasion, rete testis invasion, epididymis invasion, and invasion through the tunica albuginea. RESULTS: Among radiation patients, 5-year RFS was 97.2%, OS was 98.0%, and CSS was 99.3%. Among chemotherapy patients, 2-year RFS was 98.3% and OS and CSS were 100%. Among observation patients, 5-year RFS was 89.2%, OS was 98.8%, and CSS was 100%. There was no difference in OS or CSS among the groups. RFS was significantly lower for observation patients. Among observation patients, univariate analysis identified tumor size, lymphovascular invasion, and rete testis invasion as risk factors for relapse. No factors were significant on multivariate analysis. CONCLUSIONS: Our data show that adjuvant radiation and chemotherapy yield similar outcomes in the management of stage I seminoma. Observation results in a lower RFS, but patients who relapse can be salvaged; OS and CSS are not affected.

Metaplastic carcinoma of the breast: a retrospective review.

PURPOSE: Metaplastic carcinoma of the breast represents a rare and heterogeneous group of malignancies that accounts for less than 1% of all breast cancers. The purpose of this study is to better characterize the clinical management of this disease including the role of radiation therapy after surgery. We compared patients that have been treated with either modified radical mastectomy (MRM) or breast-conserving surgery (BCS). METHODS AND MATERIALS: We performed a retrospective review of 43 patients with metaplastic breast cancer who were evaluated in our regional radiation oncology department between 1987 and 2002. Twenty-one patients were treated with an MRM and 22 with BCS. Five patients from the MRM group received adjuvant radiation, as did 19 patients from the BCS group. Univariate and multivariate analysis of pathologic and treatment-related factors was performed. Local control, disease-free, and overall survival rates were calculated by the Kaplan-Meier method and compared for the two groups. RESULTS: Mean follow-up for all patients was 44.2 months. Mean tumor size was 3.4 cm. Four patients (9%) had positive estrogen receptors and 20 (25%) had positive nodes. The overall 5-year projected local recurrence-free (88% vs. 85%, p = 0.86), disease-free (55% vs. 84%, p = 0.13), and overall survivals (80% vs. 89%, p = 0.58) were not significantly different for both groups. The only tumor parameter significantly associated with overall survival was nodal status. CONCLUSION: Our study suggests that breast conservation appears to be a reasonable treatment option for women with metaplastic breast cancer, achieving equal survival to mastectomy. The use of adjuvant radiation seems essential for achieving high local control rates after conservation therapy. Further studies will be needed to determine the impact of chemotherapy on survival outcomes.