Leksell Gamma Knife (lgk) Radiosurgery In Unusual Histotypes Of Low-grade Neuroepithelial Brain Tumors (lgnebts)Gerosa Massimo1, Antonio Nicolato1, Roberto Foroni1, Francesco Lupidi1, Michele Longhi1, Antonio De Simone2, Franco Alessandrini1, Mario Ganau1, Alberto Beltramello1, Sergio Turazzi11Department of Neurosurgery, University Hospital, Verona, Italy 2Vr, Italy Keywords: brain tumor, gamma knife, radiosurgery, low-grade glioma, neuropathology
LGK efficacy in pilocytic and fibrillary astrocytoma (grade I/II WHO Classification) is well described. On the contrary, the efficacy and safety of radiosurgery in rarer types of LGNEBTs is much less known.
The authors report the results of 16-year experience with LGK on such neoplasms
Since February 1993, more than 6,100 patients were treated with LGK at our Department and 26 of them (27 lesions) harboured an unusual form of LGNEBTs. Histological types and patient characteristics as concerns M/F ratio, mean age, and volume were as follows: 8 choroid plexus papillomas (6/2, 44.2 years, 3.71 cc), 9 pineocytomas (4/5, 32.6, 5.1 cc), 3 (4 lesions) central neurocytomas (1/2, 30 years, 6.49 cc), 3 pleomorphic xanthoastrocytomas (1/2, 48 years, 7.3 cc), 2 gangliogliomas (1/1, 17.5 years, 6,0 cc), and 1 papillary glioneuronal tumor (F, 20-year-old, 0.9 cc).
All the neoplasms were histologically verified. LGK was the primary treatment in 8/27 lesions (bioptic diagnosis) and secondary post-operative approach in 19/27. All the patients were followed for at least 2 years.
The median follow-up period was 67.9 months (24.1-191.7). The dead were 4/26: the cause was local tumor progression in 2 (pleomorphic xantroastrocytoma and choroid plexus papilloma) or distant progression in the other two (pineocytoma and choroid plexus papilloma). Stable/improved neurologic condition, local tumor growth control (TGC), 5-year actuarial survival and progression-free survival rates on the whole series and in the different histotypes were as follows: 81% (21/26), 89% (24/27), 59%, 88%; choroid plexus papillomas: 50% (4/8), 87.5% (7/8), 83%, 87,5%; pineocytomas: 100% (9/9), 100% (9/9), 86%, 100%; central neurocytomas: 100% (3/3), 75% (3/4); pleomorphic xanthoastrocytomas: 67% (2/3), 67% (2/3); gangliogliomas: 100% (2/2), 100% (2/2). The patient with papillary glioneuronal tumor is alive, well and with complete response at 104 months from LGK. To date, no LGK-related permanent complications were observed. The 5 neurologic worsenings (4 dead) were always due to tumor progression.
This is a retrospective study.
Good neurologic results, high TGC rates, and no permanent complications suggest that LGK may be considered an effective and safe primary or secondary treatment approach in selected patients with unusual LGNEBTs also.
Additional experience from ours and other centers is required. Project Roles:
G. Massimo (), A. Nicolato (), R. Foroni (), F. Lupidi (), M. Longhi (), A. De Simone (), F. Alessandrini (), M. Ganau (), A. Beltramello (), S. Turazzi ()