paediatrics Brussels 17

Int. J. Radiation Oncology Biol. Phys., Vol. 71, No. 1, pp. 87–97, 2008 Copyright 2008 Elsevier Inc. Printed in the USA. All rights reserved 0360-3016/08/$–see front matter

doi:10.1016/j.ijrobp.2007.09.037

CLINICAL INVESTIGATION

Brain

A RETROSPECTIVE STUDY OF SURGERYAND REIRRADIATION FOR RECURRENT EPENDYMOMA

T HOMAS E. M ERCHANT , D.O., P H .D., F REDERICK A. B OOP , M.D., L ARRY E. K UN , M.D., AND R OBERT A. S ANFORD , M.D.

Department of Radiological Sciences, Division of Radiation Oncology, St. Jude Children’s Research Hospital, Memphis, TN

Purpose: To report disease control for patients with recurrent ependymoma (EP) treated with surgery and a second course of radiation therapy (RT 2 ). Patients and Methods: Thirty-eight pediatric patients (median age, 2.7 years) with initially localized EP at the time of definitive RTunderwent a second course of RT after local ( n = 21), metastatic ( n = 13), or combined ( n = 4) fail- ure. Reirradiation included radiosurgery ( n = 6), focal fractionated reirradiation ( n = 13), or craniospinal irradi- ation (CSI; n = 19). Results: Initial time to failure was 16 months, and median age at second treatment was 4.8 years. Radiosurgery resulted in significant brainstem toxicity and one death (median dose, 18 Gy). Progression-free survival ratio was greater than unity for 4 of 6 patients; there was one long-term survivor. Three of 13 patients treated using focal fractionated reirradiation (median combined dose, 111.6 Gy) experienced metastasis. The CSI was administered to 12 patients with metastatic failure, 3 patients with local failure, and 4 patients with combined failure. The 4-year event-free survival rate was 53% ± 20% for 12 patients with metastatic failure treated with CSI. Failure after CSI was observed in 1 of 3 patients with a history of local failure and 3 of 4 patients with a history of combined failure. Conclusion: Patients with locally recurrent EP experience durable local tumor control, but remain at risk of metas- tasis. Patients with metastatic EP failure may receive salvage therapy that includes a component of CSI. Durability of disease control and long-term effects from this approach require further follow-up. 2008 Elsevier Inc.

Radiotherapy, Re-treatment, Ependymoma, Pediatrics, CNS neoplasms, Toxicity.

INTRODUCTION

We identified 38 patients with EP recurrent after previous surgery and conventionally fractionated RT and subse- quently treated with radiosurgery, focal fractionated reirra- diation (FFRT), or craniospinal irradiation (CSI) at our institution. We reviewed treatment and outcomes for these patients with the hope of developing guidelines for reirradia- tion or highlighting the relative risks based on clinical infor- mation. From a review of the data, three groups emerged to focus our effort to outline strategies for the use of radiation as a salvage therapy for patients with EP. Thirty-eight patients with EP recurrent after surgery and RT and subsequently treated by using single-fraction radiosurgery ( n = 6), FFRT ( n = 13), and CSI ( n = 19) were identified for an institutional review board–approved retrospective review. Review of patient information included, at a minimum, date of birth, diagnosis, surgery, chemotherapy, RT, disease progression RPG-99-252-01-CCE from the American Cancer Society, and the American Lebanese Syrian Associated Charities. Presented in part at The Children’s Oncology Group Fall Meet- ing, Los Angeles, CA, Oct 3–7, 2006. Conflict of interest: none. Received Jan 13, 2007, and in revised form Sept 5, 2007. Accepted for publication Sept 12, 2007. PATIENTS AND METHODS

Children with ependymoma (EP) for which treatment fails after surgery and radiation therapy (RT) have few options: chemotherapy may prolong survival, but is not curative, and surgeons are reluctant to approach recurrent disease with- out the backing of effective adjuvant salvage therapy. Fractionated reirradiation may be a potential treatment for these patients. However, guidelines have not been estab- lished, relative benefits and risks are unknown, and most re- ported reirradiation series included patients with diverse diagnoses and combined adult and pediatric patients (1, 2) . Single-fraction radiosurgery was used in selected patients with locally recurrent or metastatic EP with mixed results. Morbidity was high, and durable disease control was not clearly shown (3, 4) . Fractionated reirradiation has not been systematically explored for patients with EP, mainly because these patients tend to be young and pediatric oncologists are not familiar with reirradiation as a treatment option. Reprint requests to: Thomas E. Merchant, D.O., Ph.D., Division of Radiation Oncology, Mail Stop 220, St. Jude Children’s Research Hospital, 332 North Lauderdale Street, Memphis, TN 38105. Tel: (901) 495-3604; Fax: (901) 495-3113; E-mail: thomas.merchant@ stjude.org Supported in part by Cancer Center Support Grant No. CA21765 from the National Cancer Institute, Research Project Grant No.

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