San Antonio, October 18, 2015—Outcomes for pediatric patients as young as 12 months old with ependymoma who are treated with immediate post-operative radiation therapy are favorable and consistent based upon the patients' tumor surgical resection and tumor grade, according to research presented today at the American Society for Radiation Oncology's (ASTRO's) 57th Annual Meeting.

The Children's Oncology Group ACNS0121 trial was a prospective study for childhood ependymoma (EP)— a rare type of brain and spinal cord tumor that arises from the ependyma, a tissue of the central nervous system. This was the largest prospective trial for childhood ependymoma ever conducted and the first cooperative group trial for ependymoma to target the post-operative tumor bed and to use three-dimensional conformal radiation therapy (3-D CRT) and intensity-modulated radiation therapy (IMRT). In addition, this study is significant in that it was the first to systematically use immediate post-operative radiation therapy in children under the age of three with this type of brain tumor. Many children diagnosed with ependymoma are younger than three years old. Prior studies did not include the use of radiation therapy in frontline management for very young children with ependymoma.

The study was conducted from 2003 to 2007 to determine the rate of tumor control in children with ependymoma who were treated with conformal radiation therapy using a 1cm clinical target volume margin surrounding the post-operative tumor bed. The underlying goals were to reduce the volume of radiation therapy and decrease the risk of side effects without affecting the rate of tumor control.
The trial included 378 patients from 115 institutions. The average patient age was 5.3 years (range 1.01-21.01 years), and each patient had been newly diagnosed. There were 216 patients with World Health Organization (WHO) grade II tumors and 140 with WHO grade III tumors. Patients were enrolled in the study within 56 days of initial surgical resection (removal of part or all of the tumor).

Researchers categorized the patients into non-overlapping subgroups or stratums. The study was designed to observe patients with WHO grade II; supratentorial ependymoma (tumors in the upper part of the brain) after microscopically complete (GTR1) surgical resection (stratum 1); administer chemotherapy with optional second surgery prior to conformal radiation therapy (CRT) for patients with subtotal (STR) resection at the time of protocol enrollment (stratum 2); administer immediate post-operative CRT for patients with either near-total (NTR defined as

More HCB News