ID #662 Treatment approaches for CNS tumors with BCOR ITD

High grade neuroepithelial tumors of the central nervous system (CNS) with BCL-6 corepressor (BCOR) with internal tandem duplication (ITD) are rare and aggressive pediatric tumors without standardized treatment options. These tumors are histologically embryonal tumors and molecular profiling is necessary to establish the diagnosis. These patients are treated per available case reports and case series. We are presenting our institutional experience with two cases.

Case1

2-year-old presented with right hand weakness. Imaging showed mass measuring 10.6cm arising from left cerebral hemisphere, negative spine imaging. She underwent gross total resection (GTR). Pathology showed high-grade neuroepithelial tumor with BCOR ITD. Treated per Children’s Oncology Group protocol ACNS0334 with three intensive induction cycles and three autologous transplants. Two years later she presented with right-sided hemiplegia and partial seizure. Imaging showed a 2.1cm nodule in the surgical bed with hemorrhage. Underwent GTR, craniospinal irradiation to 26.3Gy, tumor boost to 56.5Gy and chemotherapy with bevacizumab, irinotecan and temozolomide, and now in remission over 6 years from recurrence.

Case 2

2-year-old presented with headache and abnormal gait and found to have a right frontal lobe mixed solid and cystic mass, negative spine imaging. Bifrontal craniotomy was performed to achieve GTR. The pathology showed malignant CNS tumor with BCOR ITD. The patient was treated similarly to case 1 with three intensive induction chemotherapy cycles followed by high-dose chemotherapy with autologous transplant, and then focal radiation to the primary tumor site to 51Gy. The patient is in remission for the past 6 months.

Conclusion

Even though diagnostic challenges are being met through molecular profiling, the treatment options remain unstandardized. Both patients did well with a combination of intensive chemotherapy, autologous stem cell transplant and irradiation and remain disease-free. This case series emphasizes the need to standardize treatment approaches for CNS tumors with BCOR ITD.