Medical Student Lou and Jean Malnati Brain Tumor Institute, Robert H. Lurie Comprehensive Cancer Center of Northwestern University
Introduction: Central Neurocytoma (CN) is an extremely rare, WHO grade 2 brain tumor that predominantly affects young adults. Gross total resection (GTR) is curative in many instances but may not be achieved due to the intraventricular locations of CNs. The optimal treatment paradigm for CN—especially following subtotal resection (STR)—has yet to be established, including whether or not adjuvant radiotherapy (RT) should be pursued over conservative surveillance. Herein, we reviewed long-term outcomes of CN patients at our institution.
Methods: Patients between the years 2001 and 2021 with a pathologic diagnosis of CN were reviewed. Demographic, treatment, and tumor characteristics (histopathological and molecular) were recorded. Recurrence free survival (RFS) and overall survival (OS) were calculated according to the Kaplan Meier-method.
Results: Sixteen patients met the criteria for data analysis. With a median follow-up of 7.3 years, our cohort experienced zero tumor-related mortality. RFS at 2, 5, and 10 years were 80%, 72%, and 72% respectively. All patients remained free of disease progression following RT—either with adjuvant delivery after STR or salvage treatment after initial tumor recurrence. 5/9 patients (55%) were treated with stereotactic radiosurgery (SRS) and the rest (45%) were treated with fractionated external beam radiotherapy (EBRT). Patients who received STR and/or had atypical tumors (utilizing a cut off of Ki-67 >4%) experienced decreased RFS compared to those who received GTR and/or were without atypical tumors.
Conclusion : We present the clinical findings from one of the largest single-center CN cohorts. Notably, we provide encouraging evidence that (1) CNs have limited risk of tumor-related mortality and (2) RT at any point after STR conveys strong long-term tumor control. Additionally, a Ki-67 of >4% best predicted worse outcomes in our cohort, supporting the adoption of more specific criteria for atypical designation than what is currently commonly used (Ki-67 >2%).
