Clinical Outcomes and Prognostic Analysis of 101 Patients of Central Neurocytoma: A 10-Year Treatment Experience at a Single Institution

Abstract

Objective: Central neurocytoma (CN) is a rare type of tumor that currently lacks an optimal treatment protocol. This study aimed to explore the clinical outcomes of CN in a cohort of 101 patients and identify prognostic factors associated with multiple treatment modalities.

Methods: This monocentric study retrospectively analyzed the clinical data of 101 CN patients who underwent surgical resection. The patients were followed up, and their overall survival (OS) and progression-free survival (PFS) were calculated.

Results: For the entire cohort, the 5- and 10-year OS rates were 88.7% and 82.8%, respectively, and the 5- and 10-year PFS rates were 86.5% and 64.9%, respectively. Of the 82 (81.19%) patients with CN who underwent gross total resection (GTR), 28 (28/82, 34.1%) also received radiotherapy (RT). Of the 19 (18.81%) patients with CN who underwent subtotal resection (STR), 11 (11/19, 57.9%) also received RT or stereotactic radiosurgery (SRS). Compared to STR, GTR significantly improved the 5-year OS (92.4% vs. 72.4%, P=0.011) and PFS (92.4% vs. 60.4%, P=0.009) rates. Radiotherapy did not affect OS in the GTR group (p=0.602), but it had a statistically significant effect on OS in the STR group (P<0.001). However, the OS (P=0.842) and PFS (P=0.915) in the STR plus radiotherapy group were comparable to those in the GTR alone group. Compared to STR alone, STR plus radiotherapy improved the 5-year PFS rate from 25% to 75% in patients with atypical CN (P=0.004). Cox regression models and a competing risk model showed that the removal degree and radiotherapy were independent prognostic factors for survival. With improvements in modern radiotherapy techniques, severe radiotherapy toxicity was not observed.

Conclusion: Our findings support the use of GTR whenever possible. Radiotherapy can improve the prognosis of patients who undergo STR, especially in atypical CNs having a higher tendency to relapse. Close imaging follow-up is necessary. Our findings will help clinicians to select optimal, individualized treatment strategies to improve OS and PFS for patients with CN.

Keywords: atypical neurocytoma; central neurocytoma; prognostic factors; radiotherapy; survival outcomes; treatment.

Figure 1

Dose distribution in a CN patient treated with IMRT. Color-wash areas: 59.40Gy (red), 54.00Gy (yellow), 51.30Gy (orange), 48.60Gy (purple), 43.20Gy (blue), 37.80Gy (green). CN, central neurocytoma; HT, Helical tomotherapy. (A, B) refer to cross section CT, (C) refer to coronal CT and (D) refer to sagittal CT.

Figure 2

The OS and PFS in all patients (A, B). The effects of removal degree on OS and PFS in all patients (C, D). The effects of removal degree on OS and PFS in all patients treated by RT (E, F). The effects of radiotherapy on OS and PFS in patients treated by STR (G, H). OS curves for patients with different baseline conditions in terms of gender, age, tumor size and KPS (I–L). The effects of RT on OS in patients treated by GTR (M). OS curves of CN patients with different treatments (N). OS and PFS in the GTR alone group compared to the STR with radiotherapy group in all CNs (O, P). The effects of removal degree on OS and PFS in atypical CNs (Q, R). The effects of RT on OS and PFS in atypical patients treated by STR (S, T). OS curves for typical versus atypical patients in GTR (U) groups. The effects of RT on OS in atypical patients treated by GTR (V). OS (W) and PFS (X) curves of different type in all patients.

Figure 3

Multivariate Cox regression analysis of factors affecting survival benefit of patients.

Figure 4

Light microscopy of the surgical specimens reveals small round cells, perinuclear halos in fibrillary neuropils. (A) hematoxylin–eosin stain, original magnification ×200. (B) hematoxylin–eosin stain, original magnification ×400. And the immunohistochemical features of CN. Tumor cells are positive for SYN (C), NEUN (D). (E) Ki-67, (F) GFAP is positive in some CNs.